Metastatic colorectal carcinoma to one ovary with vanishing primary: A case report in an 18-year- old patient

Abstract

An 18-year-old young woman with chief complaint of left rib pain and increasing girth. An abdominal CT-scan showed a 34 x 26 cm complex right pelvic mass. Due to the young patient’s age, a fertility preservation surgery was recommended, and unilateral salpingo-oophorectomy was planned but then proceeded to tumor staging. Microscopically, the mass was composed of back to back glands, lined by hyperchromatic nuclei and prominent nucleoli, with ample mucin cytoplasm. Immunohistochemistry showed tumor positive for pan cytokeratin (AE1/3), CK20, CDX2 and negative for CK7, CD30, calretinin, glypican, PAX8, ER/PR, α fetoprotein (AFP), α -inhibin, Placental phosphatase protein (PLAP), OCT4, EMA and p53. There was no loss of mismatch repair proteins in tumor cells. The final diagnosis was metastatic adenocarcinoma from colorectal primary. Subsequently, the search for the primary carcinoma returned negative. The patient just finished 5 cycles of adjuvant FOLFOX therapy (5-fluorouracil and Oxaliplatin) with no side effects.