Should pheochromocytoma size influence surgical approach? A comparison of 90 malignant and 60 benign pheochromocytomas

Abstract

Background: Diagnostic tests cannot reliably distinguish malignant from benign pheochromocytomas. Laparoscopic adrenalectomy for pheochromocytomas >6 cm is controversial because of a perceived increased risk of malignancy that is based on anecdotal reports and small series. The aim of this study was to determine if pheochromocytoma size should affect the choice of surgical approach.

Methods: Malignant pheochromocytomas in the Surveillance Epidemiology and End Results (SEER) database (1988-2000) were compared to benign pheochromocytomas in our institutional database (1993-2003). The sensitivity, specificity and likelihood ratio for tumor size to predict malignancy were calculated for both groups.

Results: Ninety malignant and 60 benign pheochromocytomas were compared. Overall, malignant pheochromocytomas were larger than benign pheochromocytomas (7.6 +/- 4.2 cm vs 5.3 +/- 2.3 cm). However, tumor size was not significantly different between malignant pheochromocytomas without local invasion or metastases and benign pheochromocytomas (6.1 +/- 3.1 cm vs 5.3 +/- 2.3 cm). In pheochromocytomas with local disease only, maximum likelihood ratio to predict malignancy was at a tumor size of greater than 8 cm (2.84).

Conclusions: Although risk of malignancy increases with size for all pheochromocytomas, size does not reliably predict malignancy in pheochromocytomas with local disease only. Regardless of tumor size, laparoscopic adrenalectomy for pheochromocytoma should be converted to open adrenalectomy for difficult dissection, invasion, adhesions, or surgeon inexperience.