Flow cytometric analysis does not reliably differentiate benign from malignant phaeochromocytoma

Abstract

In this study, three of nine patients with an apparently benign diploid cytometric pattern subsequently developed recurrent disease. Routine use of DNA flow cytometry did not reliably differentiate benign from malignant phaeochromocytoma. Prolonged clinical and biochemical follow-up is still necessary for all patients with this condition.

KI-67 AND hTERT Expression Can Aid in the Distinction between Malignant and Benign Pheochromocytoma and Paraganglioma

“…Conflicting results have been reported for DNA flow cytometry (13,31,32), overexpression of the proto-oncogene products c-erb B-2 and bcl-2 (a marker of apoptosis; 16,33,34), mutations in the tumor suppressor gene p53 and its product (14,33,35), elevated plasma neuropeptide Y levels (36, 37), elevated urinary dopamine levels reflecting an immature secretion pattern (27), and absence of S-100 sustentacular cells (16,17). Immunohistochemical staining for the cell adhesion molecule E-cadherin (14), the oncogene product of HER-2/neu (14), PCNA (a marker of proliferative activity; 13), somatic mutations in the RET proto-oncogene (17), and angiogenesis assessed by high microvascular count (15) seem to have no potential diagnostic utility in this tumor type.…”

Proliferative index in phaeochromocytomas: does it predict the occurrence of metastases?

“…It appears that secretory profiles are not diagnostic for malignancy, although dopamine secretion is more commonly found in malignant cases14, 26. Furthermore, despite initial optimism27, DNA ploidy studies do not reliably discriminate benign from malignant phaeochromocytomas28, 29.…”

Cyclooxygenase‐2 expression correlates with phaeochromocytoma malignancy: evidence for a Bcl‐2‐dependent mechanism

“…Following approval from Queen’s University Research Ethics Committee, 40 sporadic phaeochromocytoma patients with a minimum of 5‐years follow‐up postdiagnosis were identified from the Northern Ireland Neuroendocrine Tumour register 15 . Tumours were classified as malignant in the presence of clinically documented metastases, tumour recurrence or extensive local invasion 15 . An additional patient who developed recurrent disease and died within the 5‐year period was also included, because it was possible to confirm malignant disease in this individual.…”

“…15 Tumours were classified as malignant in the presence of clinically documented metastases, tumour recurrence or extensive local invasion. 15 An additional patient who developed recurrent disease and died within the 5-year period was also included, because it was possible to confirm malignant disease in this individual. The associated formalin-fixed paraffin-embedded specimens (n = 41) were obtained for immunohistochemical analysis.…”