Primary leiomyosarcoma of the breast: A case report and literature review

Introduction: Primary leiomyosarcoma is an uncommon form of stromal breast sarcoma. Approximately 73 cases have been documented in English-language literature to date. To our knowledge, this is the first report from Indonesia of an adolescent female with primary leiomyosarcoma of the breast.Case presentation: A 30-year-old Southeast Asian female presented with a tumor in her left breast. Clinical examination revealed a 12 x 8-centimeter tumor. The supraclavicular, subclavicular, and axillary lymphadenopathy were not palpable. An ultrasound revealed a Breast Imaging Reporting and Data System category 5. Abdominal ultrasonography and chest x-ray were normal, as were blood chemistry and routine blood tests. A wide excision with a surgical margin of 2 cm was performed. Pathological investigation identified the mass as a leiomyosarcoma. The pelvis, abdomen, and lung CT scan metastatic workups were negative. The patient is well 8 months post-surgery, with no signs of recurrence.Clinical discussion: Wide local excision has been the mainstay of treatment for leiomyosarcoma; however, there is no accepted standard of treatment due to the rarity of the disease.Conclusion: Breast leiomyosarcomas have a more favorable prognosis than other breast neoplasms; however, patients must be closely monitored for recurrence or metastases. While there are no known predictors of outcomes, the margins of the initial surgery, mitotic activity, and atypia cellularity are more indicative of malignancy.