Invaluable role of histopathology in the diagnosis of cutaneous leiomyosarcoma in insulin injection site reaction

Soft tissue sarcomas (STSs) are rare and may often be misdiagnosed, resulting in delays in treatment. A 67-year-old cisgender woman with type 2 diabetes mellitus and obesity presented to her primary care physician with a mass on her left proximal arm. The clinical opinion of the attending physician was that of an insulin injection site reaction. After further evaluation from the physician, the patient was diagnosed with a lipoma without confirmatory histology. The patient continued to present with an enlarging mass, decline in health status and continued with local wound care. The patient underwent a confirmatory biopsy following which, the patient was diagnosed with leiomyosarcoma. This case report highlights the case of a person with a low or moderate income with a self-reported low health literacy living in a rural community and how STS may be misdiagnosed in medically underserved. The patient’s primary or oncology care team are not involved in the production or review of this case report.