Tag: Difference b/w Schwannoma & Neurofibroma

Von Recklinghausen’s Disneurofibromatosisease

(VON RECKLINGHAUSEN’S DISNEUROFIBROMATOSISEASE)


NEUROFIBROMATOSIS (VON RECKLINGHAUSEN’S DISEASE)

  • Neurofibromatosis type 1 (NF1) and type 2 (NF2) are neurocutaneous disorders inherited as autosomal dominant genetic syndromes..

Neurofibromatosis type 1

  • The clinical criteria used to diagnose NF1 are as follows, in the absence of alternative diagnoses:
  • Six or more café-au-lait spots or hyperpigmented macules =5 mm in diameter in prepubertal children and 15 mm postpubertal
  • Axillary or inguinal freckles (>2 freckles)
  • Two or more typical neurofibromas or one plexiform neurofibroma
  • Optic nerve glioma
  • Two or more iris hamartomas (Lisch nodules), often identified only through slit-lamp examination by an ophthalmologist
  • Sphenoid dysplasia or typical long-bone abnormalities such as pseudarthrosis
  • First-degree relative (eg, mother, father, sister, brother) with NF1.

Neurofibromatosis type 2 

  • It is a genetic disorder marked by the predisposition to develop a variety of tumors of the central and peripheral nervous systems. In contrast to neurofibromatosis type 1 (NF1), NF2 produces a paucity of cutaneous manifestations.
  • Clinical diagnosis of NF2 requires that an individual present with at least 1 of the following clinical scenarios :
  • Bilateral vestibular schwannomas
  • A first degree relative with NF2 and Unilateral vestibular schwannoma or Any two of: meningioma, schwannoma, glioma, neurofibroma, posterior subcapsular lenticular opacities
  • Unilateral vestibular schwannoma and Any two of: meningioma, schwannoma, glioma, neurofibroma, posterior subcapsular lenticular opacities
  • Multiple meningiomas and Unilateral vestibular schwannoma or Any two of: schwannoma, glioma, neurofibroma, cataract.

Difference b/w Schwannoma & Neurofibroma

Schwannoma (or Neurilemmoma)

  • are true encapsulated neoplasm composed of schwann cells.
  • It compresses the nerve of origin.
  • There is a plane of cleavage separating the nerve from the mass.

Neurofibroma

  • are unencapsulated benign neoplasm of schwann cells and fibroblasts.
  • The tumor involves the nerve. Grossly it appears as expanded nerve.
  • It is composed of mixture of schwann cell and fibroblast and contains axons within it.
  • It can not be demarcated from the nerve therefore can not be removed without sacrificing the nerve.

Difference between NF-1 and NF-2:

Feature

NF1

NF2

Mutation

NFl gene on chromosome 17 causes

NF2 gene on chromosome 22q.

von Recklinghausen’s disease. The NFl

NF2 encodes a protein called

gene is a tumor-suppressor gene; it encodes a protein, neurofibromin

neurofibromin 2, schwannomin,or merlin

Cutaneous feat

cutaneous neurofibromas, pigmented

lesions of the skin called café au lait

spots, freckling in non-sun-exposed

areas such as the axilla, hamartomas

of the iris termed Lisch nodules, and

pseudoarthrosis of the tibia

Multiple café au lait spots and

peripheral neurofibromas occur

rarely                                                   

Complications

Aqueductal stenosis with

hydrocephalus, scoliosis, short stature,

hypertension, epilepsy, and mental

retardation may also occur.

A characteristic type of cataract,

juvenile posterior subcapsular

lenticular opacity, occurs in NF2

Neurological features

Patients with NF1 are at increased

risk of developing nervous

system neoplasms, including plexiform

neurofibromas, optic pathway gliomas

ependymomas, meningiomas

astrocytomas, and

pheochromocytomas. Neurofibromas

may undergo secondary malignant

degeneration and become

sarcomatous.

NF2 is characterized by the

development of bilateral vestibular

schwannomas in >90% of

individuals who inherit the gene

Patients with NF2 also have a

predisposition for the development

of meningiomas, gliomas, and

schwannomas of cranial and spinal

nerves

Exam Important

  • Neurofibromatosis shows which of the Autosomal Dominant type of inheritance.
  • Neurofibromatosis may be associated with Cataract, Scoliosis, Hypertrophy of limb and Neurofibroma.
  •  Neurofibromatosis-1 is asociated with family history, Optic Glioma and Axillary Freckles.
  • Optic Gliomas are the most common intracranial tumors of Neurofibromatosis 1.
  • Neurofibromatosis type 2 is associated with Bilateral Acoustic Neuroma, Cafe-au-lait spots, Axillary Freckling, Lisch Nodule, Meningioma
  • Gene for NF-2 is located on chromosome 22.
  • Neurofibroma are unencapsulated and needs to be resected along the nerve fibres.
  • Neurofibromatosis presents as Elephantiasis neuromatodes, Plexiform neuroma,Von Recklinghausen’s disease.
  • Plexiform neurofibromatosis commonly affects Trigeminal Nerve.
  • Neurofibromatosis may be associated with Pheochromocytoma.
  • The pathognomic sign of Neurofibromatosis is Axillary Freckling.
  • Scoliosisis is the MOST common skeletal manifestation in Type-1 Neurofibromatosis.
  • Juveile Myelomonocytic Leukemia  is the most common tumour associated with Neurofibromatosis -1 (NF-I) in a child.
  • Rib notching,Pseudarthrosis may be seen in Neurofibromatosis.
  • Wide neural foramina is associated with Neurofibromatosis.-I.
  • Ependymomas are commonly associated with Neurofibromatosis-II.
  • A 22-year-old patient, Sreeraj presents with multiple neural tumors, pigmented iris hamartomas, and numerous tan macules on his skin. He informs the physician that his father, as well as one uncle and his paternal grandfather, had a similar condition. This patient likely suffers from Neurofibromatosis.-I.
Don’t Forget to Solve all the previous Year Question asked on (VON RECKLINGHAUSEN’S DISNEUROFIBROMATOSISEASE)

Module Below Start Quiz

Von Recklinghausen’s Disneurofibromatosisease

(VON RECKLINGHAUSEN’S DISNEUROFIBROMATOSISEASE)

Q. 1

All are seen in neurofibromatosis EXCEPT?

 A Meningioma
 B

Lisch nodule

 C Axillary freckling
 D

Shagreen patch

Q. 1

All are seen in neurofibromatosis EXCEPT?

 A Meningioma
 B

Lisch nodule

 C Axillary freckling
 D

Shagreen patch

Ans. D

Explanation:

Shagreen patch REF: Harrison’s 17th ed chapter 374

“Shagreen patch is seen in tuberous sclerosis”

Feature

NF1

NF2

Mutation

NFl gene on chromosome 17 causes

NF2 gene on chromosome 22q.

 

von Recklinghausen’s disease. The NFl

NF2 encodes a protein called

 

gene is a tumor-suppressor gene; it

encodes a protein, neurofibromin

neurofibromin 2, schwannomin,

or merlin

Cutaneous feat              

cutaneous neurofibromas, pigmented

lesions of the skin called café au lait

spots, freckling in non-sun-exposed

areas such as the axilla, hamartomas

of the iris termed Lisch nodules, and

pseudoarthrosis of the tibia                      

Multiple café au lait spots and

peripheral neurofibromas occur

rarely                                                   

Complications

Aqueductal stenosis with

hydrocephalus, scoliosis, short stature,

hypertension, epilepsy, and mental

retardation may also occur.

A characteristic type of cataract,

juvenile posterior subcapsular

lenticular opacity, occurs in NF2

Neurological features

Patients with NF1 are at increased
risk of developing nervous
system neoplasms, including plexiform
neurofibromas, optic pathway gliomas
ependymomas, meningiomas
astrocytomas, and
pheochromocytomas. Neurofibromas
may undergo secondary malignant
degeneration and become

sarcomatous.

 
NF2 is characterized by the
development of bilateral vestibular
schwannomas in >90% of
individuals who inherit the gene
Patients with NF2 also have a
predisposition for the development
of meningiomas, gliomas, and
schwannomas of cranial and spinal

nerves


Q. 2

Neurofibromatosis true all, except ‑

 A

Autosomal recessive

 B

Associated with cataract

 C

Scoliosis

 D

Multiple fibroma

Q. 2

Neurofibromatosis true all, except ‑

 A

Autosomal recessive

 B

Associated with cataract

 C

Scoliosis

 D

Multiple fibroma

Ans. A

Explanation:

Autosomal recessive [Ref: Robbin’s 7thle p. 1413]

  • Neurofibromatosis is an inherited disorder
  • It is of two types: ?
  • Neurofibromatosis

– Neurofibromatois II

Genetics of Neurofibromatosis

  • Both the neurofibromas are inherited in an autosomal dominant pattern.
  • The genes for them are located on different chromosome 

         – NF-1—) Neurofibrin gene on chromosome 17
         – NF-2 —) Merlin gene on chromosome 22

NEUROFIBROMATOSIS TYPE I ?

  • Neurofibromatosis is a comparatively common hereditary disorder in which the skin, nevous system, bone, endocrine glands and sometimes other organs are at the sites of a variety of congenital abnormalities often taking the fonn of benign tumours.

. The main feature of neurofibromatosis I is –

(i) Spots of hyperpigmentation

and

(ii)    Cutaneous and subcutaneous neurofibromatous tumours’.

Hyperpigmentation in Neurofibromatosis I takes two forms 😕

a) Cafe – au – lait spots’

.   These are patches of pigmentation and they appear shortly after birth’ and occur anywhere on the body.

.   They are light brown in colour (cafe – au – lait) and do not change in number as the patient ages but they increase in size during puberty.

.   Presence of more than six cafe – au – lait spots > 1.5 cm in size is considered diagnostic of Neurofibromatosis.

b) Freckles’

.   Neurofibromatosis I is also characterized by the presence of Freckles like or diffuse pigmentation of the axillae and other intertriginous areas (groin, under breast) and small round whitish spots. When coupled with cafe au lait patches they are virtually pathogtzomonice of the disease.

ii) Neurofibromas

a) Cutaneous tumours

.   They are situated in the dermis and form discrete soft or, firm papules.

.   They are ,flesh coloured or violaceous and often topped with comedo. When pressed, the soft tumours tend to invaginate through a small opening in the skin giving the feeling of a seedless raisin or a scrotum without a testicle. This phenomenon is spoken of as “button holding”.

b) Subcutaneous tumours

.   They take two forms ?

a)   Firm discrete nodules attached to a nerve.

b) Plexiform neuromase (overgrowth of subcutaneous tissue sometimes reaching enormous size and occur most often in the face, scalp, neck and chest and may cause hideous disfigurement).

Lisch Nodule’?

  • This is another unique .finding of neurofibromatosiso.

.   It is a small whitish spote present in the iris.

Tumours associated with Neurofibromatosis I are

1) Tumours of the CNS

a)  Optic Nerve Gliomao

b)  Non-optic Gliomas (usually low grade astrocytomas)

c)   Nonneoplastic ‘ hamartomatous” lesion

Osborn writes –

“The common CNS tumor in NF-1 is optic nerve glioma occuring in 5 to 15% of casese”

2) Other tumours associated with NF-1

a)  Pheochromocytoma

b)  Rhabdomyosarcoma

c)   leukemia (myeloid leukemia)

d)     Wilms tumour

e) Juvenile Xanthogranuloma


Q. 3

Neurofibromatosis I is most commonly associated with

 A

Brain stern gliomas

 B

Optic pathway glioma

 C

Sub ependymal pilocytic astrocytoma

 D

Glioblastoma multifonne

Q. 3

Neurofibromatosis I is most commonly associated with

 A

Brain stern gliomas

 B

Optic pathway glioma

 C

Sub ependymal pilocytic astrocytoma

 D

Glioblastoma multifonne

Ans. B

Explanation:

Optic pathway Glioma [Ref Diagnostic Neuroadiology; Anne G.Osborn, 1994]

Tumours associated with Neurofibromatosis I are

1) Tumours of the CNS

a) Optic Nerve Gliomao

b) Non-optic Gliomas (usually low grade astrocytomas)

c) Nonneoplastic ” hamartomatous” lesion

Osborn writes ?

“The common CNS tumor in NF-1 is optic nerve glioma occuring in 5 to 15% of cases’)”

2) Other tumours associated with NF-1

a) Pheochromocytoma

b) Rhabdomyosarcoma

c)  leukemia (myeloid leukemia)

d)  Wilms tumour

e)  Juvenile Xanthogranuloma

Quiz In Between


Q. 4 A 22-year-old patient, Sreeraj presents with multiple neural tumors, pigmented iris hamartomas, and numerous tan macules on his skin. He informs the physician that his father, as well as one uncle and his paternal grandfather, had a similar condition. This patient likely suffers from which of the following?

 A

Ependymoma

 B

Huntington disease

 C

Marfan syndrome

 D

Neurofibromatosis type I

Q. 4

A 22-year-old patient, Sreeraj presents with multiple neural tumors, pigmented iris hamartomas, and numerous tan macules on his skin. He informs the physician that his father, as well as one uncle and his paternal grandfather, had a similar condition. This patient likely suffers from which of the following?

 A

Ependymoma

 B

Huntington disease

 C

Marfan syndrome

 D

Neurofibromatosis type I

Ans. D

Explanation:

Neurofibromatosis type 1, or von Recklinghausen disease, is an autosomal dominant disorder with high penetrance, but variable expressivity. The disease has three major features:
(1) multiple neural tumors anywhere on or in the body
(2) numerous pigmented cutaneous lesions (café au lait spots); and
(3) pigmented iris hamartomas (Lisch nodules).

Electron micrographic studies show that the tumors are the result of the proliferation of fibroblasts or Schwann cells in the peripheral nerves, possibly due to ras inactivation.
There is no treatment, except for surgical resection of symptomatic tumors.

Ependymoma  can occur wherever ependymal cells are found. They are more common in children, and most often originate in the fourth ventricle. They are the most common intramedullary glioma of the spinal cord.
 
Huntington disease, an autosomal dominant disorder, is characterized by severe degeneration of the caudate nucleus along with degenerative changes in the putamen and cortex.
In addition to chorea, these patients frequently suffer from athetoid movements, progressive dementia, and behavioral disorders.
 
Marfan syndrome  is due to a defect in the gene for fibrillin.
The major clinical findings involve the skeleton, cardiovascular system, and the eye.
Affected individuals tend to be tall with long extremities and long, tapering appendages.
Mitral valve prolapse and dilatation of the aortic valve ring or aortic dissection due to cystic medial degeneration are common.

Q. 5 Ependymomas are commonly associated with:

 A

Tuberous sclerosis

 B

Neurofibromatosis 1

 C

Neurofibromatosis 2

 D

All of the above

Q. 5

Ependymomas are commonly associated with:

 A

Tuberous sclerosis

 B

Neurofibromatosis 1

 C

Neurofibromatosis 2

 D

All of the above

Ans. C

Explanation:

Ependymomas most often arise next to the ependyma-lined ventricular system, including the oft-obliterated central canal of the spinal cord. In the first two decades of life they typically occur near the fourth ventricle and constitute 5% to 10% of the primary brain tumors in this age group. In adults the spinal cord is the most common location; tumors in this site are particularly frequent in the setting of neurofibromatosis type 2
            
Ref: Robbins 8th edition Chapter 28.

Q. 6

Which of the following is the most common tumour associated with Neurofibromatosis -1 (NF-I) in a child?

 A

Juveile Myelomonocytic Leukemia (JMML)

 B

Acute Lymphoblastic Leukemia (ALL)

 C

Acute Myeloid Leukemia (AML)

 D

Chronic Myeloid Leukemia (CML)

Q. 6

Which of the following is the most common tumour associated with Neurofibromatosis -1 (NF-I) in a child?

 A

Juveile Myelomonocytic Leukemia (JMML)

 B

Acute Lymphoblastic Leukemia (ALL)

 C

Acute Myeloid Leukemia (AML)

 D

Chronic Myeloid Leukemia (CML)

Ans. A

Explanation:

Children with neurofibromatosis type 1 have higher risk of developing juvenile myelomonocytic leukemia.
Ref: Essential pediatrics by O.P.Ghai 6th edn/page 545; Rook’s textbook of dermatology, Volume 1 By Arthur Rook, Tony Burns (FRCP.)page 2-32.

Quiz In Between


Q. 7

Pseudarthrosis may be seen in all of the following conditions, EXCEPT:

 A

Fracture

 B

Idiopathic

 C

Neurofibromatosis

 D

Osteomyelitis

Q. 7

Pseudarthrosis may be seen in all of the following conditions, EXCEPT:

 A

Fracture

 B

Idiopathic

 C

Neurofibromatosis

 D

Osteomyelitis

Ans. D

Explanation:

Causes of Pseudarthrosis (In decreasing order of frequency) are:

  • Neurofibromatosis (50% patients of pseudarthrosis have NF)
  • Nonunion of fracture (including pathological fracture)
  • Congenital (mostly in lower to middle third of tibia with cupping of proximal bone end and pointing of distal bone end)
  • Idiopathic
  • Osteogenesis imperfecta
  • Fibrous dysplasia
  • Cleidocranial dysplasia
  • Ankylosing spondylitis (in fused bamboo spine)
  • Post surgical e.g. triple arthrodesis, spinal fusion etc. as a complication. 
Ref: Robbin’s Pathologic basis of Disease 7/e, Page 1289; Apley’s system of Orthopedics & fractures 8/e, Page 156,164,544 ; Natarajan’s orthopedics , Page 27; Murcer’s Orthopedic surgery 9/e, Page 433, 811, 1095, 672,736.

Q. 8 Which of the following is the MOST common skeletal manifestation in Type-1 Neurofibromatosis?

 A

Cortical thinning of long bones

 B

Pseudoarthrosis

 C

Sphenoid dysplasia

 D

Scoliosis

Q. 8

Which of the following is the MOST common skeletal manifestation in Type-1 Neurofibromatosis?

 A

Cortical thinning of long bones

 B

Pseudoarthrosis

 C

Sphenoid dysplasia

 D

Scoliosis

Ans. D

Explanation:

Von Recklinghausen’s Disease or NF-1 – skeletal manifestations
 
Scoliosis is the most common skeletal manifestation of NF-1, affecting 10%–30% of patients.
 
More Info: There are two other bony lesions distinctive enough to be included in the diagnostic criteria for NF-1. 
 
1. Dysplasia of the wing of the sphenoid bone, results in poor formation of the wall and/or floor of the orbit. This leads to proptosis (from herniation of meninges or brain into the orbit) or enophthalmos.
 
2. Dysplasia of a long bone, characterized by congenital thinning and bowing, affects approximately 2% of children with NF-1.
Although the tibia is most commonly affected, the femur, humerus and other long bones may also be involved.
Failure of primary union following a fracture results in a “false joint” or pseudarthrosis.
 
Ref: Listernick R., Charrow J. (2012). Chapter 141. The Neurofibromatoses. In L.A. Goldsmith, S.I. Katz, B.A. Gilchrest, A.S. Paller, D.J. Leffell, N.A. Dallas (Eds), Fitzpatrick’s Dermatology in General Medicine, 8e.

Q. 9

All of the following statements about Neurofibromatosis are true, except?

 A

Cataract

 B

Scoliosis

 C

Cutaneous neurofibromas

 D

Autosomal Recessive Inheritance

Q. 9

All of the following statements about Neurofibromatosis are true, except?

 A

Cataract

 B

Scoliosis

 C

Cutaneous neurofibromas

 D

Autosomal Recessive Inheritance

Ans. D

Explanation:

Neurofibromatoses are a group of clinically and genetically different autosomal dominant hereditary diseases that predispose to benign and malignant tumors of the nervous system. It is of two types NF 1 and NF2.
Cutaneous neurofibromas occur in NF1, and NF 2 is associated with posterior subcapsular cataract.

Ref: Harrison’s Internal Medicine, 18th Edition, Chapter 379; Color Atlas of Genetics By Eberhard Passarge, 3rd Edition, Page 338

Quiz In Between


Q. 10

All of the neurocutaneous signs are seen in Neurofibromatosis Type 2, EXCEPT:

 A

Meningioma

 B

Lisch nodule

 C

Axillary freckling

 D

Shagreen patch

Q. 10

All of the neurocutaneous signs are seen in Neurofibromatosis Type 2, EXCEPT:

 A

Meningioma

 B

Lisch nodule

 C

Axillary freckling

 D

Shagreen patch

Ans. D

Explanation:

Shagreen patch is highly characteristic of tuberous sclerosis and is seen in 80% of patients. It occurs in early childhood and may be the first sign of disease. They are soft, flesh colored to yellow plaques with an irregular surface. It is most commonly seen in the lumbosacral region. 

Features of Neurofibromatosis 1 are: cafe au lait spots, neurofibromas or plexiform neuroma, freckling, optic glioma and Lisch nodules.

Features of Neurofibromatosis 2 are: bilateral vestibular schwannomas, multiple meningioma, spinal ependymoma, astrocytoma, posterior subcapsular lens opacities and retinal hamartomas.


Q. 11

Which of the following is associated with bilateral eighth nerve neuromas?

 A

Neurofibromatosis I

 B

Neurofibromatosis II

 C

Tuberous sclerosis

 D

All of the above

Q. 11

Which of the following is associated with bilateral eighth nerve neuromas?

 A

Neurofibromatosis I

 B

Neurofibromatosis II

 C

Tuberous sclerosis

 D

All of the above

Ans. B

Explanation:

Neurofibromatosis Type II is characterized by bilateral tumors of the eighth cranial nerve (the vestibulocochlear nerve) and any of the following: meningiomas, schwannomas, gliomas, or juvenile subcapsular cataracts.


Q. 12

Which one of the following is the most common tumor associated with type I neurofibromatosis

 A

Optic nerve glioma

 B

Meningioma

 C

Acoustic schwannoma

 D

Low grade astrocytoma

Q. 12

Which one of the following is the most common tumor associated with type I neurofibromatosis

 A

Optic nerve glioma

 B

Meningioma

 C

Acoustic schwannoma

 D

Low grade astrocytoma

Ans. A

Explanation:

Ans. is ‘a’ i.e., Optic nerve glioma

Neurofibromatosis type I (Von-Recklinghewsen diseasel

o NF- 1 is diagnosed when any two of the following seven signs are present.

1. Six or more cafe-au-lait macules

o > 5 mm in prepupertal individuals

o > 15 mm in postpubertal individuals

  • Cafe-au-lait spots are the hallmark of neurofibromatosis and are present in almost 100% of the patient.
  1. Axillary or inguinal freckling
  2. Two or more Lisch nodules.
  • Lisch nodules are hamartomas located within the iris.
  1. Two or more neurofibroma or one plexiform neurofibroma.

o Typically involve the skin, but may be situated along peripheral nerves and blood vessels. o They are small, rubbery lesions with a slight purplish discoloration of the overlying skin.

  1. A distinctive osseous lesion.
  • Sphenoid dysplasia or cortical thinning of long bones.
  1. Optic glioma
  2. A first degree relative with NF-1

o Other findings are : ‑

o Pseudoarthrosis of tibia.

  • Scoliosis is the most common orthopaedic problem in NF-1, but is not specific enough to be included as a diagnostic criterian.
  • Short stature

o Mental retardation, epilepsy

o Hypertension

o Aqueductal stenosis with hydrocephalus

o Meningiomas, ependynomas, Astrocytomas, pheochromocytomas.

o NF-1 is caused by mutation in NF-1 gene on chromosome 17 which encodes protein neurofibromin-1. Neurofibromatosis type -2

o NF-2 may be diagnosed when one of the following two features are present.

  1. Bilateral ocoustic neuroma Most distinctive feature
  2. A parent, sibling or child with NF-2 and either unilateral eighth nerve masses or any two of the following —> Neurofibroma, meningioma, glioma, Schwannoma or juvenile post subcapsular cataract.

o NF-2 is cause by mutation in NF-2 gene on chromosome 22 that encodes for protein neurofibromin 2, Schwannomin or merlin.

Quiz In Between


Q. 13 Neurofibromatosis true all, except-

 A

Autosomal recessive

 B

Associated with cataract

 C

Scoliosis

 D

Multiple fibroma

Q. 13

Neurofibromatosis true all, except-

 A

Autosomal recessive

 B

Associated with cataract

 C

Scoliosis

 D

Multiple fibroma

Ans. A

Explanation:

Ans. is ‘a’ i.e., Autosomal recessive

o Neurofibromatosis comprises of two distinct disorders –

  • Neurofibromatosis I

 Neurofibromatosis II

o The genes for these are located on different chromosomes.

o Both are inherited in an autosomal dominant pattern.

o The classical form of the disease with multiple neuromas is called Neurofibromatosis I and is caused by a mutation of the gene neurofibromin on chromosome 17


Q. 14

Which one of the following is the most common tumor associated with type I neurofibromatosis

 A

Optic nerve glioma

 B

Meningioma

 C

Acoustic schwannoma

 D

Low grade astrocytoma

Q. 14

Which one of the following is the most common tumor associated with type I neurofibromatosis

 A

Optic nerve glioma

 B

Meningioma

 C

Acoustic schwannoma

 D

Low grade astrocytoma

Ans. A

Explanation:

Ans. is ‘a’ i.e., Optic nerve glioma

Neurofibromatosis type I (Von-Recklinghewsen disease)

o NF-1 is diagnosed when any two of the following seven signs are present.

1. Six or more cafe-au-lait macules

             > 5 mm in prepupertal individuals

             > 15 mm in postpubertal individuals

               Cafe-au-fait spots are the hallmark of neurofibromatosis and are present in almost 100% of the patient.

2. Axillary or inguinal freckling
3. Two or more Lisch nodules.

             Lisch nodules are hamartomas located within the iris.

4. Two or more neurofibroma or one plexiform neurofibroma.

             Typically involve the skin, but may be situated along peripheral nerves and blood vessels.

             They are small, rubbery lesions with a slight purplish discoloration of the overlying skin.

5. A distinctive osseous lesion.

             Sphenoid dysplasia or cortical thinning of long bones.

6. Optic glioma
7. A first degree relative with NF-1

Other findings are : –

             Pseudoarthrosis of tibia.

             Scoliosis is the most common orthopaedic problem in NF-1, but is not specific enough to be included as a diagnostic criterian.

             Short stature


Q. 15 Wide neuralforamina is associated with:

 A

Neurofibromatosis type 1

 B

Sturge-Weber syndrome

 C

Von Hipple Lindau disease

 D

Tuberous sclerosis

Q. 15

Wide neuralforamina is associated with:

 A

Neurofibromatosis type 1

 B

Sturge-Weber syndrome

 C

Von Hipple Lindau disease

 D

Tuberous sclerosis

Ans. A

Explanation:

A i.e. Neurofibromatosis

Neurofibromatosis type 1 is associated with widening (enlargement) of neural foraminaQ (mostly secondary to dumbbell neurofibroma along exiting spinal nerve root or less commonly d/t dural ectasia, arachnoid cyst or lateral menngocele)Q, scalloping of posterior vertebral bodies, enlargement of internal auditory canal (d/t dural dysplasia), enlargement of optic foramen (d/t optic glioma), enlargement of orbital margins & superior orbital fissure (d/t plexiform neurofibroma) and sclerosis of optic foramen (d/t optic nerve sheath meningioma).

NF1 causes empty orbitQ, Herlequin appearance of orbit and herniation of middle cranial fossa structures into orbit d/t sphenoid bone hypoplasia.

Both neurofibromas (common in NF1) and Schwannomas (common in NF2) are benign nerve sheath tumors mostly found in intradural extramedullary location. Both are derived from Schwann cells, however, neurofibromas also have colagen & fibroblasts. Vestibular or acoustic Schwannoma (or neurilemmoma or acoustic neuroma of 8th cranial nerve) seen in NF2 1/t internal auditory canal (IAC) enlargement (erosion d/t mass centered on long axis of IAC forming acute angles with dural surface of petrous bone) and widening or obliteration of ipsilateral cerebello pontine angle cistern.

NF-2 is located on chromosome 22 and NF1 on chromosome 17(Mn 1 for 1 & 2 for 2). NF2 have propensity for developing MEN/MES i.e. meningioma, ependymoma (gliomas) and Schwannoma (neuromas). Nerves without Schwann cells are olfactory and optic nerve.

Schwannomas neurofibromas, on CT, appear as sharply marginated, unilateral, spherical, or lobular posterior mediastinal mass, with pressure erosion of adjacent rib or vertebral bodies or enlargment of neural foramen with occasional punctate intralesional calcifcation. Owing to their high lipid content, interstitial fluid and areas of cystic degeneration – Schwannomas are often of lower attenuation than skeleton muscle. Neurofibromas are often more homogenous & of higher attenuation than schwannomas (owing to fewer of above histological features). These may heterogenously enhance on contrast administration. On MRI both show variable intensity on T1WI but typically have similar signal intensity to the spinal cord. On T2WI these characteristically have high signal intensity peripherally and low signal intensity centrally (target sign) owing to collagen deposition. Both schwannoma & neurofibroma enhance on gadolinium administration.

Quiz In Between


Q. 16

Rib notching is found in :

 A

Neurofibromatosis

 B

Lymphangiomyomatosis

 C

Aortic aneurysm

 D

a and c

Q. 16

Rib notching is found in :

 A

Neurofibromatosis

 B

Lymphangiomyomatosis

 C

Aortic aneurysm

 D

a and c

Ans. D

Explanation:

A i.e. Neurofibromatosis; C i.e. Aortic aneurysm


Q. 17

Neurofibromatosis all are true except

 A

Autosomal recessive

 B

Scoliosis

 C

Neurofibroma

 D

Association with cataract

Q. 17

Neurofibromatosis all are true except

 A

Autosomal recessive

 B

Scoliosis

 C

Neurofibroma

 D

Association with cataract

Ans. A

Explanation:

A i.e. Autosomal recessive


Q. 18

The pathognomonic sign of neurofibromatosis is

 A

Cafe-au-lait macules

 B

Axillary frekling

 C

Shagreen patch

 D

None of the above

Q. 18

The pathognomonic sign of neurofibromatosis is

 A

Cafe-au-lait macules

 B

Axillary frekling

 C

Shagreen patch

 D

None of the above

Ans. B

Explanation:

B i.e. Axillary freckling

Neurofibromatosis is autosomal dominantQ disorder. Axillary freckling (crowe sign) is a pathognomic sign of von- Reckling hausen’s type 1 neurofibromatosisQ. Café – au – lait macules alone are not absolutely diagnostic of NF1, regardless of their size and number.

Quiz In Between


Q. 19 Neurofibromatosis is associated with –

 A

Papillary Ca

 B

Islet cell tumour

 C

Pheochromytoma

 D

Glucagonoma

Q. 19

Neurofibromatosis is associated with –

 A

Papillary Ca

 B

Islet cell tumour

 C

Pheochromytoma

 D

Glucagonoma

Ans. C

Explanation:

Ans. is ‘c’ i.e. Pheochromocytoma 

Following neoplasms are associated with Neurofibromatosis

Type I (Von Recklinghausen ds.)

Type II

Neurofibromas (including plexiform neurofibromas)

Bilateral vesibular schwannomas

 

Pheochromocytoma

 

Schwannoma of other cranial and spinal nerves

 

Optic gliomas

Meningioma

 

Ependymomas

Gliomas

 

Meningiomas

 

Schwannomas

 

Astrocytomas

 

 

 

Q. 20 Plexiform neurofibromatosis commonly affects…

 A

Facial nerve      

 B

Trigeminal nerve

 C

Peripheral nerve

 D

Glossopharyngeal nerve

Q. 20

Plexiform neurofibromatosis commonly affects…

 A

Facial nerve      

 B

Trigeminal nerve

 C

Peripheral nerve

 D

Glossopharyngeal nerve

Ans. B

Explanation:

Ans. is ‘b’ i.e., Trigeminal nerve 


Q. 21

Musculo skeletal abnormality in neurofibromatosis is

 A

Hypertrophy of limb

 B

Scoliosis

 C

Cafe au lait spots

 D

All

Q. 21

Musculo skeletal abnormality in neurofibromatosis is

 A

Hypertrophy of limb

 B

Scoliosis

 C

Cafe au lait spots

 D

All

Ans. D

Explanation:

Ans. is `d’ i.e., All 

Quiz In Between


Q. 22

Neurofibromatosis presents as all of the following except –

 A

Elephantiasis neuromatodes

 B

Plexiform neuroma

 C

Von Recklinghausen’s disease

 D

Lymphadenovarix

Q. 22

Neurofibromatosis presents as all of the following except –

 A

Elephantiasis neuromatodes

 B

Plexiform neuroma

 C

Von Recklinghausen’s disease

 D

Lymphadenovarix

Ans. D

Explanation:

Ans. is ‘d’ i.e., Lymphadenovarix 


Q. 23

Not true regarding neurofibromatosis is ‑

 A

Never become malignant

 B

Is encapsulated

 C

Resected along nerve fibres

 D

a and b

Q. 23

Not true regarding neurofibromatosis is ‑

 A

Never become malignant

 B

Is encapsulated

 C

Resected along nerve fibres

 D

a and b

Ans. D

Explanation:

Ans is ‘a’ ie Never becomes malignant & ‘b’ i.e. is encapsulated

Malignant transformation of neurofibromas occurs in 5-10% of cases

Neurofibromatosis (or von Recklinghausens ds)

  • is the MC hereditary neurocutaneous syndrome.
  • There are two forms of neurotibromatosis, both Autosomal dominant*

Neurofibromatosis type I is characterized by :

Neurofibromatosis type II is characterized by :

numerous neurofibromas in the skin &

peripheral nerves.

the development of b/l vestibular

schwannomas in >90% of individuals*.

pigmented pathes in the skin k/a cafe au lait

spots.

pt. also has prediliction for development of

gliomas*, meningioma and schwannomas of

Freckling in non-sun exposed areas such as

 

cranial & spinal nerves.

 

the axilla.

Vestibular schwannomas (or Acoustic

hamartornas of iris termed Lisch nodules

 

neuromas)* usually present with progressive

Pseudoarthrosis of tibia.

 

deafness early in the third decade of life.

Diffuse proliferation of nerve elements may

cause massive enlargement of tissues

 

 

 

(Elephantiasis neurofibromatosa or

 

 

 

Elephant man disease)*

 

 

 

  • Schwannomas are encapsulated but neurofibromas are not Therefore Schwannomas can be resected surgically without sacrificing the nerve but in neurofibromas the nerve has to be resected along.

Difference b/w Schwannoma & Neurofibroma

  • Schwannoma (or Neurilemmoma)
  • are true encapsulated neoplasm composed of schwann cells.
  • It compresses the nerve of origin.
  • There is a plane of cleavage separating the nerve from the mass .
  • Neurofibroma
  • are unencapsulated benign neoplasm of schwann cells and fibroblasts.
  • The tumor involves the nerve. Grossly it appears as expanded nerve.
  • It is composed of mixture of schwann cell and fibroblast and contains axons within it.
  • It can not be demarcated from the nerve therefore can not be removed without sacrificing the nerve.

Q. 24 Neurofibromatosis type 2 is associated with:

 A

B/L acoustic neuroma

 B

Cafe-au-lait spots

 C

Chromosome 22

 D

All

Q. 24

Neurofibromatosis type 2 is associated with:

 A

B/L acoustic neuroma

 B

Cafe-au-lait spots

 C

Chromosome 22

 D

All

Ans. D

Explanation:

 

B/L acoustic neuromas are a hallmark of Neurofibromatosis 2

  • Neurofibromatosis Type 2 is an autosomal dominant highly penetrant condition
  • Gene for NF-2 is located on chromosome 22q.
  • Patients with NF2 present in second and third decade of life, rarely after the age of 60.
  • M/C symptom/Presenting symptom = Hearing loss
  • Skin tumors are present in nearly two thirds of patients of NF-2

-Current Otolaryngology 3/e

 


Quiz In Between


Q. 25

All of the following statements about Neurofibromatosis are true, Except:

 A

Autosomal Recessive Inheritance

 B

Cutaneous neurofibromas

 C

Cataract

 D

Scoliosis

Q. 25

All of the following statements about Neurofibromatosis are true, Except:

 A

Autosomal Recessive Inheritance

 B

Cutaneous neurofibromas

 C

Cataract

 D

Scoliosis

Ans. A

Explanation:

Answer is A (Autosomal Recessive inheritance):
Neurofibromatosis is inherited as an autosomal dominant condition

Neurofibromatosis

Oculoneurocutaneous syndrome characterized by multisystem involvement

Neurofibromatosis I (NF 1)            

Peripheral Neurofibromatosis (Von Recklinghausen’s syndrome)

•   Most prevalent type (90%)

•  Recognized to be related to abnormality of chromosome 17 (NFI gene)

•  Transmitted as an Autosomal Dominant disorder

Diagnostic Criteria for NF I

Diagnosed when any two of the following are present

1. Six more cafe-au-loit macules over 5 mm in greatest diameter in prepubertal individuals and over 15 mm in greatest diameter in post-pubertal individuals.

2. Axillary or inguinal freckling

3. Two or more iris Lisch nodules

4. Two or more neurofibromas or one plexiform neurofibroma

5. A distinctive osseous lesion such as sphenoid dysplasia or cortical thinning of long bone, with or without pseudoarthrosis.                                                          

6. Optic gliomas.

7. A first degree relative with NFI whose diagnosis was based on the aforementioned criteria.

Note

Scoliosis is the most common orthopaedic manifestation of

NFl although it is not specific enough to be included as a diagnostic criteria — Nelson 18th/2483


Neurofibromatosis II (NF II)                            

Central Neurofibromatosis (Bilateral Acoustic Neurofibromatosis)

•  Less prevalent type (10%) recognized to be related to

abnormality of chromosome 22 (NF2 gene)

•  Transmitted as an Autosomal dominant disorder

Diagnostic Criteria for NF2

 

Diagnosed when any one of the following is present.

 

1 . Bilateral eighth nerve masses consistent with acoustic

neuromas as demonstrated by CT scanning or MRI

2. A parent, sibling, or child with NF-2 and either

3. unilateral eight nerve mass or any two of the following:

– Neurofibroma

– Meningioma

– Glioma

– Schwannoma

 

Juvenile posterior subcapsular opacity

 

 

Bilateral acoustic neuromas are the most

distinctive tumors in patients with NF-2.

 

 

 

 

Note

 

Posterior subcapsular lens opacities (cataract) are

 

identified in 50% of patients with NF2

 

— Nelson 181h/2484



Q. 26 Which of the following is the most common tumor associated with type I neurofibromatosis?

 A

Optic nerve glioma.

 B

Meningioma

 C

Acoustic Schwannoma

 D

Low grade astrocytorna.

Q. 26

Which of the following is the most common tumor associated with type I neurofibromatosis?

 A

Optic nerve glioma.

 B

Meningioma

 C

Acoustic Schwannoma

 D

Low grade astrocytorna.

Ans. A

Explanation:

Answer is A (Optic Nerve Glioma):
The commonest tumor in neurofibromatosis I is optic nerve gliomna. Optic gliomas are present in approximately 15% of patients with NFI and its presence is included as one of the criteria in establishing its diagnosis.

Neoplasms associated with NF-I include:

 

CNS Neoplasms

Others tumors with higher incidence than general population

1.

Optic nerve glioma (commonest)

1.

Pheochromocytomas

2.

Meningiomas

2.

Rhabdomyosarcomas

3.

NeurojIbromas

3.

Leukaemia

4.

Schwannomas

4.

Wilm’s

5.

Astrocytomas

5.

Juvenile Xanthogranulomas

6

Neurolemmomas

 

 

 


Q. 27

Neurofibromatosis I is most commonly associated with:

 A

Brain stem gliomas

 B

Optic pathway glioma

 C

Sub ependymal pilocytic astrocytoma

 D

Glioblastoma multiforme

Q. 27

Neurofibromatosis I is most commonly associated with:

 A

Brain stem gliomas

 B

Optic pathway glioma

 C

Sub ependymal pilocytic astrocytoma

 D

Glioblastoma multiforme

Ans. B

Explanation:

Answer is B (Optic Nerve Glioma):

Optic Gliomas are present in about 15 to 25% of patient with NF-I and its presence is included as one of the criteria in establishing its diagnosis (Diagnostic criteria in NFl)

Optic Gliomas are the most common intracranial tumors of Neurofibromatosis 1- Child Neurology

Quiz In Between


Q. 28 Lisch nodules are seen in: 
March 2004

 A

Albright syndrome

 B

Neurofibromatosis

 C

Tuberous sclerosis

 D

Piebaldism

Q. 28

Lisch nodules are seen in: 
March 2004

 A

Albright syndrome

 B

Neurofibromatosis

 C

Tuberous sclerosis

 D

Piebaldism

Ans. B

Explanation:

Ans. B i.e. Neurofibromatosis

Lisch nodule

  • It is a pigmented hamartomatous nodular aggregate of dendritic melanocytes affecting the iris
  • These nodules are found in neurofibromatosis type 1, and are present in greater than 94% of patients over the age of six.
  • They are clear, yellow-brown, oval to round, dome-shaped papules that project from the surface of the iris.
  • These nodules typically do not affect vision, but are very useful in diagnosis.
  • They are detected by slit lamp examination. lmmunohistochemistry stains positive against vimentin and S-100, and points to an ectodermal origin.
  • They are not found in neurofibromatosis type 2.

Q. 29 Pheochromocytoma is usually associated with:
September 2007

 A

Pancreatic exocrine carcinoma

 B

Astrocytoma

 C

Neurofibromatosis

 D

Neuroblastoma

Q. 29

Pheochromocytoma is usually associated with:
September 2007

 A

Pancreatic exocrine carcinoma

 B

Astrocytoma

 C

Neurofibromatosis

 D

Neuroblastoma

Ans. C

Explanation:

Ans. C: Neurofibromatosis

Pheochromocytoma linked to MEN II cart be caused by RET oncogene mutations. Both syndromes are characterized by pheochromocytoma as well as thyroid cancer (thyroid medullary carcinoma). MEN IIA also presents with hyperparathyroidism, while MEN IIB also presents with mucosal neuroma.

Pheochromocytoma is also associated with neurofibromatosis


Q. 30 Lisch nodules are seen in:           
March 2009

 A

Retinoblastoma

 B

Neurofibromatosis

 C

Retiniitis pigmentosa

 D

Neuroblastoma

Q. 30

Lisch nodules are seen in:           
March 2009

 A

Retinoblastoma

 B

Neurofibromatosis

 C

Retiniitis pigmentosa

 D

Neuroblastoma

Ans. B

Explanation:

Ans. B: Neurofibromatosis

Quiz In Between


Q. 31

NOT a feature of Neurofibromatosis-1:
September2012

 A

Ash leaf spots

 B

Family history

 C

Optic glioma

 D

Axillary freckle

Q. 31

NOT a feature of Neurofibromatosis-1:
September2012

 A

Ash leaf spots

 B

Family history

 C

Optic glioma

 D

Axillary freckle

Ans. A

Explanation:

Ans. A i.e. Ash leaf spots

Dermatological conditions and important findings

Tuberous sclerosis:

– Ash leaf spot,

– Adenoma sebaceum

– Shagreen patches

  • Urticaria pigmentosa: Darrier’s sign
  • Amyloidosis: Pinch purpura
  • Lichen planus:

– Wickham’s striae,

– Civatte bodies

  • Atopic dermatitis: Dennie Morgan folds
  • Pityriasis rosacea:

– Herald patch, Mother patch

– Annular collratte of scales


Q. 32 Glioma of optic nerve is associated with ‑

 A

Neurofibromatosis type I

 B

Neurofibromatosis type II

 C

Both the above

 D

None of the above

Q. 32

Glioma of optic nerve is associated with ‑

 A

Neurofibromatosis type I

 B

Neurofibromatosis type II

 C

Both the above

 D

None of the above

Ans. A

Explanation:

Ans. is ‘a’ i.e., Neurotibromatosis type I

Optic nerve glioma

Optic nerve glioma (astrocytoma) is the most common intrinsic tumor of the optic nerve. Most common type of optic nerve glioma is juvenile pilocytic astrocytoma. The majority of optic nerve gliomas are of astrocytic origin. However, a few rare optic nerve gliomas arise from oligodendrocytes. 70% of optic gliomas occur during first decade of life. Optic nerve gliomas are associated with Neurofibromatosis-1 (Von Recklinghausen’s disease) in 55% of cases. 75% of optic gliomas arise from optic chiasma and adjacent optic nerve. 25% are confined to optic nerve alone (orbital optic nerve glioma).

Patients present with some degree of unilateral visual dysfunction, visual field loss, afferent pupillary defect, decreased ocular motility, optic atrophy, pain headache and nystagmus. Proptosis is often the chief complaint of an orbital glioma. Nystagmus may also occur. Other late features of optic nerve glioma are neovascular glaucoma, anterior segment ischemia and hemorrhagic glaucoma from retinal vascular occlusion.

In chiasmal gliomas there may be visual field defects, raised ICT, papilloedema and endocrine abnormalities like diabetes insipidus, hypopituitarism, dwarfism and precocious puberty.


Q. 33

Lisch nodule seen in ‑

 A

Sympathetic ophthalmitis

 B

Neurofibromatosis

 C

Chronic iridocyclitis

 D

Trachoma

Q. 33

Lisch nodule seen in ‑

 A

Sympathetic ophthalmitis

 B

Neurofibromatosis

 C

Chronic iridocyclitis

 D

Trachoma

Ans. B

Explanation:

Ans. is ‘b’ i.e., Neurofibromatosis
Lisch nodules are the most common type of ocular involvement in NF-1. These nodules are melanocytic hamartomas, usually clear yellow to brown, that appear as well-defined, dome-shaped elevations projecting from the surface of the iris.

Quiz In Between


Q. 34

Neurofibromatosis true is all except ‑

 A

Autosomal recessive

 B

Associated with cataract

 C

Scoliosis

 D

Multiple fibroma

Q. 34

Neurofibromatosis true is all except ‑

 A

Autosomal recessive

 B

Associated with cataract

 C

Scoliosis

 D

Multiple fibroma

Ans. A

Explanation:

Ans. is `a’ i.e., Autosomal recessive


Q. 35

Neurofibromatosis shows which of the following mode of inheritance ‑

 A

AD

 B

AR

 C

X linked dominant

 D

X linked recessive

Q. 35

Neurofibromatosis shows which of the following mode of inheritance ‑

 A

AD

 B

AR

 C

X linked dominant

 D

X linked recessive

Ans. A

Explanation:

Ans. is ‘a’ i.e., AD

Neurofibromatosis shows autosomal dominant inheritance pattern

  • Single gene disorders (Mendelian disorders) typically follow one of the three patterns of inharitance
  1. Autosomal dominance
  2. Autosomal recessive
  3. X-linked

Autosomal dominant disorders

  • Normally a gene pair has two alleles.
  • When one allele becomes abnormal due to mutation it is called heterozygous state.
  • When both the alleles become abnormal due to mutation it is called homozygous state.
  • Autosomal dominant disorders are manifested in heterozygous state, i.e. only if one allel is abnormal the disease will be manifested.

Quiz In Between



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