Extraadrenal and multiple pheochromocytomas. Are there really any differences in pathophysiology and outcome?

In 15-20% of the cases pheochromocytoma (pheo) localizes in extraadrenal sites and in about 15% of all cases it seems to be multiple. We analyze our 20-year experience in surgical treatment of pheos, studying the differences between typical and extraadrenal or multiple tumors. From 1977 to 1996 we operated 55 patients (patients) with pheos, 28 (50.9%) males and 27 females (mean age 41 years, range 10-63). Two groups have been distinguished: classic pheos (Group 1, 45 patients) and extraadrenal or multiple pheos (Group 2, 10 patients). Hypertensive crises were present in 37/45 (82.2%) patients of Group 1 and in 7/10 patients of Group 2. Five (11.1%) masses were nonfunctioning and incidentally discovered (4 in Group 1 and one in Group 2). In 4 cases association with familial syndromes was observed (3 MEN IIb, 1 von Recklinghausen syndrome); no further significant differences in clinical features and laboratory data were found between the two Groups. At immunohistochemical analysis 26/26 patients resulted positive for chromogranin A and NSE and 17/26 (11/20 in Group 1 and 4/6 in Group 2) resulted positive for S 100 protein. Five (11.1%) malignant pheos were discovered and removed (Group 1); average survival of these patients was 54.4 months, two patients underwent radioactive iodine (131-I-MIBG) therapy after surgery and only one patient is still alive at 24-month follow-up. Recurrence for benign sporadic pheo (Group 1) occurred in one patient 183 months after adrenalectomy. Ectopic, associated with familial syndromes and multiple pheos are not uncommon and although recovery in surgically treated patients is excellent, lifelong follow-up is necessary also in benign tumors.