Myxoid leiomyosarcoma of the uterus - Report of a case with cytologic findings

BACKGROUND: Myxoid leiomyosarcoma is a rare variant of uterine sarcoma, exh ibiting malignant biologic behavior despite the absence of cytologic atypia and of significant mitotic activity. CASE: A 20-year-old-female was referred with a cystic pelvic mass. At lapar otomy, the tumor, weighed 2,200 g and originating in the left lateral uteri ne wall, was removed. Microscopic examination revealed well-differentiated smooth muscle cells without atypia and with a fe so mitotic figures in the copious myxoid matrix, suggesting myxoid leiomyosarcoma. Three years follow ing laparotomy, an irregular mass around the uterus teas noted on sonograph ic examination, suggesting local recurrence. Two years and six months later , the second operation was performed, and a locally recurrent, multicystic tumor weighing 3,500 g was excised. The histopathology was similar to that of the primary tumor. Cytologic findings on imprint material from the tumor revealed a few isolated or sheet like small cells consisting of spindle an d polygonal cells with round and oval nuclei. Cytologic atypia was also min imal. CONCLUSION: 12 Myxoid leiomyosarcoma should be included in the differential diagnosis of smooth muscle neoplasia.