Flow cytometric DNA analysis for determination of malignant potential in adrenal pheochromocytoma or paraganglioma: an Indian experience.

Abstract

We analyzed the histological features and DNA flow cytometric results in 34 patients with pheochromocytoma and paragangliomas and attempted correlation with the biological behavior for determination of the malignant potential of these tumors. DNA analysis was done on a FACSort flow cytometer using paraffin-embedded tissues. Histopathological analysis was performed using parameters, i.e., cell size (large, medium, and small), cell size variation, mitotic rate, nuclear pleomorphism, golden yellow to brown pigment in the tumor, necrosis, and venous invasion. Six tumors had high (>5/10HPF) mitotic rate while venous invasion was seen in three tumors. Fifty percent (18/34) of patients had aneuploid tumors, and 68% (23/34) of patients had high (>10%) S-phase fraction tumors. Aneuploidy correlated with >5/10HPF mitotic rate (P <.05) and diploidy with golden yellow to brown pigment (P <.01). The patients with aneuploid tumor had a worse prognosis than patients with diploid tumors (P =.004). No such difference was observed with low and high S-phase fractions (P =.748), presence and absence of venous invasion (P =.927), and mitotic rate (P =.159). Nuclear pleomorphism and necrosis were not significant factors in prognosis. Flow cytometric DNA analysis of paragangliomas and pheochromocytomas correlated with biological behavior in the patients with regard to metastasis and overall survival in the patients.