Adrenal cortical adenoma-cavernous hemangioma collision tumor: a case report.

Adrenal collision tumors (ACTs) are rare entities defined by the coexistence of two histologically distinct, adjacent tumors within a single adrenal gland. Accurate preoperative diagnosis is crucial for management but remains challenging. We present a rare case of ACT in a 49-year-old woman with a three-year history of limb weakness. Imaging revealed a well-defined right adrenal mass with two distinct components. On detailed multiplanar reconstruction, the cortical adenoma component was located in the lateral (outer) portion of the right adrenal gland, occupying the superior-posterior aspect and abutting the perirenal fat (approximately 35% of total tumor volume). The cavernous hemangioma component was located in the medial (inner) portion, occupying the central and inferior-anterior aspect adjacent to the inferior vena cava (approximately 65% of total tumor volume). The two components met at a well-defined planar interface oriented obliquely from superolateral to inferomedial, without evidence of infiltration. CT and MRI demonstrated distinct imaging characteristics for each component. Pathological examination confirmed the diagnosis, demonstrating a cortical adenoma coexisting with a cavernous hemangioma, sharply demarcated by a fibrous septum. This case underscores the importance of recognizing the characteristic imaging patterns of different tumor components within a single adrenal lesion. When atypical features are present within an otherwise typical tumor, an ACT should be considered to guide appropriate clinical management.