A case report of a composite pheochromocytoma that occurred 13 years after adrenalectomy for pheochromocytoma.

Purpose: To analyze the clinicopathological features, surgical management, and long-term prognosis of a composite pheochromocytoma (CP; pheochromocytoma combined with ganglioneuroma) arising 13 years after resection of a primary adrenal pheochromocytoma, with the aim of improving the clinical diagnosis and management of this rare neoplasm. Case presentation: A 61-year-old Han male had undergone left adrenal pheochromocytoma resection 13 years prior to the current presentation. An asymptomatic left adrenal nodule was incidentally detected during a routine physical examination, and the patient was subsequently admitted to the Department of Urology at The Third Hospital of Mianyang. He denied any history of other chronic systemic illnesses. Admission biochemistry revealed only a mild elevation of epinephrine, with the concentration remaining below twice the upper limit of normal. Abdominopelvic contrast-enhanced computed tomography (CT) identified a well-circumscribed hypodense nodule measuring 2.6 × 2.1 cm beneath the left adrenal gland, demonstrating marked nodular and peripheral ring enhancement; a separate hypodense nodule with a maximum diameter of 1.8 cm was also noted in the right adrenal fossa. Based on his disease history and imaging findings, recurrence of left adrenal pheochromocytoma was strongly suspected, and a synchronous right adrenal pheochromocytoma could not be excluded. The patient consented only to partial left adrenalectomy. Intraoperative exploration revealed adhesions among the descending colon, peritoneum, and spleen, as well as multiple solid masses (maximum size 2.0 × 2.0 cm) in the left adrenal region that were densely adherent to the pancreatic parenchyma. The resected specimens were submitted for pathological evaluation. Histopathological examination confirmed a composite pheochromocytoma with cystic change, multifocal coagulative necrosis, and adipose tissue invasion. The patient experienced an uneventful postoperative recovery. During the subsequent 11-month follow-up period, no recurrence or distant metastasis was detected, and the patient remained clinically stable. Conclusions: It remains challenging to definitively establish whether the left adrenal composite pheochromocytoma (CP) detected in this patient represents true tumor recurrence 13 years after the initial surgery. Archival pathological slides from the primary operation were unavailable for comparative histologic and clonal analysis. Moreover, the original lesion was diagnosed as a pure pheochromocytoma, whereas the current mass harbors an additional mature ganglioneuromatous component displaying distinct histological features. Given the lack of evaluable surgical margins from the initial partial adrenalectomy, the possibility of minimal residual disease cannot be excluded. Accordingly, two possibilities are proposed: late ipsilateral recurrence of the original chromaffin tumor, or a metachronous