A rare metachronous presentation of periductal stromal sarcoma in a case of recurrent rhabdomyosarcoma – Case report

Abstract

Periductal stromal sarcoma (PSS) is a an extremely rare low-grade malignant neoplasm arising from breast periductal stroma. It usually occurs in peri and post-menopausal women. Herein, we report a rare case of a 14 year girl, known case of recurrent Rhabdomyosarcoma (RMS) presenting with periductal stromal sarcoma of breast. To the best of our knowledge, this is a first of its kind to be reported in literature. A 14year girl, known case of Recurrent Pleomorphic Rhabdomyosarcoma of retroperitoneum, presented with an abdominal mass and lump in right breast after 10 years. On chemotherapy, abdominal mass regressed and breast lump progressed in size. On further evaluation by histopathological examination and immunohistochemistry, the breast lump turned out to be a periductal stromal sarcoma. Periductal stromal tumors have histological similarities to phyllodes tumors, with the biphasic presence of hypercellular and variably atypical, mitotically active stroma hugging benign epithelium. There are very few case reports on periductal stromal tumors and thus a rare entity. PSS as a metachronous presentation with recurrent RMS is even more rare with the prevalence of multiple soft tissue sarcomas being 0.08%. A clinically suspected metastatic lesion, if accessible for biopsy, warrants a meticulous histopathological examination to ascertain the cell of origin. The therapeutic strategy and prognosis of PSS is unclear, thus a longer follow up is imperative to determine its prognosis and clinical outcome. 2 case reported so far in younger individuals. 1st case of PSS in a Recurrent RMS.