Collision Tumors of Ovary: A Rare Finding Case Report from Quetta, Balochistan Case Report

Abstract

Collision tumors are rare pathological entities characterized by the coexistence of two histologically distinct and independent neoplasms within the same organ, without any transitional or intermixed zones. Although collision tumors have been documented in several organs, including the gastrointestinal tract, skin, adrenal glands, lymph nodes, uterus, and central nervous system, their occurrence in the ovary is exceedingly rare. We report a rare case of an ovarian collision tumor in a 48-year-old multiparous woman who presented to the Gynecology Department with complaints of vaginal itching and oligomenorrhea for six months. Laboratory investigations revealed a mildly elevated serum Cancer Antigen-125 (CA-125) level of 84.2 U/mL. Contrast-enhanced computed tomography demonstrated a well-defined, rounded cystic lesion in the right ovary. The patient underwent right ovarian cystectomy, and the excised specimen measuring 10.8 × 9.7 × 6.2 cm was submitted for intraoperative frozen section evaluation. Histopathological examination confirmed a rare collision tumor composed of serous cystadenofibroma and mature cystic teratoma. Accurate recognition of individual tumor components is essential to distinguish collision tumors from mixed neoplasms, as this has important implications for appropriate surgical management and prognostic assessment.