Misdiagnosis of popliteal leiomyosarcoma: A case report and literature review.

RATIONALE: Leiomyosarcoma (LMS) is usually derived from the uterus, retroperitoneum, or intra-abdominal region. However, it is relatively rare in the popliteal fossa and can easily lead to misdiagnoses in clinical practice.

PATIENT CONCERNS: A 52-year-old female was admitted to the hospital with a "left popliteal fossa mass that had persisted for 8 days."

DIAGNOSES: The patient was diagnosed with benign popliteal fossa tumor following admission. The final pathological diagnosis was a malignant popliteal LMS.

INTERVENTIONS: The patient underwent 2 operations. First, the tumor was completely removed with an integral envelope and sent for pathological examination; the diagnosis was LMS. Subsequently, a 2nd extended resection is performed.

OUTCOMES: Postoperatively, the patient received relevant medical antitumor therapy and was followed-up for 3 months, with no recurrence or metastasis.

LESSONS: Cases of LMS can develop in uncommon sites, such as the popliteal fossa, and present in the extremities, although rarely. Preoperative needle biopsy is recommended to confirm the nature of this type of tumor and ensure the range of excision.