Question
Which of the following tumor markers are positive for seminoma?
- PLAP
- OCT3/4
- NANOG
- HCG
| A. | 1 only |
| B. | 1 & 2 only |
| C. |
1,2,3 only |
| D. |
1,2,3,4 |
|
Correct Answer » D Explanation |
 |
Tumor markers are substances, often proteins, produced by cancer cells or by the body in response to cancer. Seminoma, a type of testicular germ cell tumor, is associated with several key tumor markers:-
PLAP (Placental Alkaline Phosphatase) – This enzyme can be elevated in several types of cancer, including seminomas. It’s a useful marker for this type of testicular cancer.
OCT3/4 (Octamer-binding transcription factor 3/4) – This is a transcription factor that maintains stem cell pluripotency and is a key marker for germ cell tumors, including seminomas. Its expression is highly indicative of seminomas.
NANOG – This is another pluripotency marker that is associated with stem cells and certain types of cancer, including germ cell tumors. While NANOG is a marker of interest in the study of seminomas and other germ cell tumors, its diagnostic utility as a standalone marker for seminomas compared to OCT3/4 and PLAP is less well-established. However, its presence alongside other markers can support the diagnosis of seminoma.
HCG (Human Chorionic Gonadotropin) – While HCG is often elevated in certain non-seminomatous germ cell tumors (such as choriocarcinomas) and can be elevated in some patients with seminomas, it is not as consistently elevated in seminomas as it is in other types of testicular cancer. Can be mildly elevated (in 10-15% of cases) due to the presence of syncytiotrophoblastic cells.
Other tumor markers seen in seminoma:
- KIT (CD117): Commonly expressed in seminomas; useful in diagnosis.
- SOX17: A transcription factor often expressed in seminomas, differentiating it from embryonal carcinoma which expresses SOX2.
- D2-40 (Podoplanin): A marker frequently expressed in seminoma, indicating lymphatic involvement.
- SALL4: A transcription factor positive in most germ cell tumors, including seminomas.
- LDH (Lactate Dehydrogenase): Often elevated in seminomas, though it is non-specific, it can be used to assess tumor burden.
