Composite pheochromocytoma of the adrenal gland: a case series

Abstract

Background: Composite pheochromocytoma is a rare pathological condition characterized by elements of both pheochromocytoma and neurogenic tumors. However, detailed clinical outcomes of this tumor have not been fully shown. From 2007 to 2013, we experienced three cases of adrenal composite pheochromocytoma. In this report, we investigate the clinicopathological features of these three cases of composite pheochromocytoma and compare them with previously reported cases.

Case presentations: Cases 1 and 2 were a 29-year-old Japanese woman and a 59-year-old Japanese man, respectively. They underwent laparoscopic left adrenalectomy, and pathological examination revealed composite pheochromocytoma-ganglioneuroma. Case 3 was a 53-year-old Japanese man who had been receiving hemodialysis for 17 years. He underwent laparoscopic right adrenalectomy, and pathological examination revealed composite pheochromocytoma-ganglioneuroblastoma. Although the Ki67-positive rates varied from 1.0 to 6.2% among the three cases, no clinical recurrences occurred. Despite the relatively high rate of Ki67 positivity, complete tumor resection resulted in favorable clinical outcomes.

Conclusion: We experienced three cases of adrenal composite pheochromocytoma. Although the clinical findings and treatment outcomes of composite pheochromocytoma were similar to those of ordinary pheochromocytoma, further studies of the biological behavior and genetic profiles of composite pheochromocytoma are necessary to achieve a better understanding of this tumor.

Figure 1

Computed tomography or magnetic resonance imaging of three composite pheochromocytomas. a Magnetic resonance imaging revealing a heterogeneous left adrenal mass (indicated by arrowhead) with slightly high intensity on T2-weighted images. b Computed tomography scan showing a left adrenal mass (indicated by arrowhead). c Magnetic resonance imaging showing acquired cystic kidney disease and a right adrenal mass (indicated by arrowhead).

Figure 2

Microscopic findings of resected tumors. Left lanes (a–c) pheochromocytoma component (hematoxylin and eosin staining, ×400). Middle lanes (d–f) ganglioneuroma or ganglioneuroblastoma components. d, e Ganglioneuroma component (hematoxylin and eosin staining, ×400). f Ganglioneuroblastoma component (Nissl staining, ×400). Right lanes (g–i) positive immunohistochemical staining of the pheochromocytoma component with Ki67 (×200).