Cytologic features of metastatic transitional cell carcinoma

Area of Science:

• Cytopathology
• Oncology
• Urologic Pathology

Background:

• Metastatic transitional cell carcinoma (MTCC) diagnosis relies on identifying characteristic cellular morphology.
• Primary transitional cell carcinoma (TCC) often presents as poorly differentiated and invasive tumors.

Purpose of the Study:

• To identify and describe the characteristic morphologic features of MTCC in cytologic preparations.
• To assess the utility of these features in diagnosing MTCC, especially when the primary tumor is unknown.

Main Methods:

• Review of cytologic preparations from 18 sites in 16 patients with confirmed MTCC.
• Analysis of morphologic features including cell shape, nuclear characteristics, and cytoplasmic differentiation.

Main Results:

• MTCC cells were pleomorphic, occurring singly or in clusters, with abundant cytoplasm and distinct cell borders.
• Key features included spindled, pyramidal, or racquet-shaped cells with eccentric nuclei and mixed squamous/glandular differentiation.
• Prominent nucleoli and hyperchromatic nuclei were common.

Conclusions:

• Specific morphologic features in cytologic samples can suggest MTCC.
• While clinical history is crucial, characteristic cell shapes and cytoplasmic features are valuable diagnostic clues.
• A definitive cytologic diagnosis of MTCC may be challenging without a known primary TCC, but suggestive features can guide further investigation.