Metastatic Hurthle cell carcinoma in the abdomen masquerading as a primary ovarian tumor: a case report.

Hurthle cell carcinoma, a variant of follicular carcinoma of the thyroid, has been regarded as an aggressive type of differentiated thyroid cancer. It is diagnosed histologically and regarded as a carcinoma by the presence of vascular invasion or capsular invasion. In this case report, a patient with a history of thyroid Hurthle cell carcinoma presented with what seemingly appeared to be a pelvic mass of gynecological origin, with a raised risk-of-malignancy index of 567. She underwent a laparotomy which revealed the presence of multiple masses in the form of nodules and lumps attached to her small bowel, sigmoid colon, omentum, and infracolic region, without the involvement of her pelvic organs or para-aortic lymph nodes. At frozen section, the masses were reported to be high-grade metastatic tumor, possibly a melanoma, unlikely to be a female genital tract tumor. These masses were resected along with a 15-cm section of small bowel and analyzed. They were diagnosed to be secondary lesions of Hurthle cell carcinoma of the thyroid. Hurthle cell carcinoma of the thyroid has not been known to be associated with the elevation of CA125 nor has it been known to metastasize to the small bowel and sigmoid colon.