Question
A 59-year-old man presents with a 3-week history of painless hematuria. Physical examination is unremarkable. Urinalysis shows 2+ hematuria. A CT scan of the abdomen reveals an exophytic mass in the renal pelvis. Cytologic examination of fine-needle aspiration of the renal pelvis is shown in the image. These cells show which of the following patterns of arrangement?
| A. |
Follicular configuration |
| B. |
Glandular structures |
| C. |
Papillary configuration |
| D. |
Rosettes |
Show Answer
|
Correct Answer » C Explanation |
|
- The patient is an older man with painless hematuria, which is a classic presentation of urothelial carcinoma.
- A mass arising in the renal pelvis strongly suggests a urothelial (transitional cell) carcinoma.
- Urothelial tumors commonly have a papillary/exophytic growth pattern.
- The uploaded material describes urothelial carcinoma as producing papillary and exophytic lesions.
- The cytologic image shows cohesive groups of tumor cells arranged around a central axis, producing a papillary configuration.
Explanation of the Image
- The image demonstrates clusters of urothelial cells arranged in branching/cohesive groups.
- The cells form a three-dimensional, frond-like pattern rather than spherical follicles, true glands, or rosettes.
- This arrangement is characteristic of a papillary urothelial tumor.
Reasons to Rule Out Other Options
A. Follicular configuration
- Incorrect.
- Follicular arrangements are characterized by cells surrounding a central lumen or colloid-like material.
- This pattern is classically associated with thyroid follicular structures, not urothelial carcinoma of the renal pelvis.
- The image does not show follicle formation.
B. Glandular structures
- Incorrect.
- Glandular structures indicate adenocarcinomatous differentiation, in which tumor cells form true glandular lumina.
- Urothelial carcinoma is an epithelial malignancy but does not characteristically form true glands.
- The renal pelvis is most commonly affected by urothelial carcinoma, rather than adenocarcinoma.
C. Papillary configuration
- Correct.
- Urothelial carcinoma commonly forms papillary and exophytic lesions.
- The cells in the image are arranged in cohesive papillary clusters.
- The clinical presentation of painless hematuria + renal pelvic mass further supports urothelial carcinoma.
D. Rosettes
- Incorrect.
- Rosettes are characteristic of certain neuroectodermal/neuroendocrine tumors.
- A classic example is the Homer Wright pseudorosette seen in neuroblastoma.
- The cells in this image do not demonstrate a rosette pattern.
