Soft Tissue Sarcoma Masquerading as Chronic Hematoma: A Case Report and Literature Review.

Introduction: Soft tissue sarcomas may resemble intramuscular hematomas in rare instances. We present a case of a patient diagnosed with pleomorphic spindle cell sarcoma that appeared similar to an intramuscular hematoma.

Case report: A 45-year-old male presented with a painful, swollen, and pus-discharging area on his left thigh. Imaging revealed gas in the soft tissues, and the patient exhibited signs of severe illness, including abnormal blood work. Upon delving into his medical history, it was revealed that he had experienced a minor fall, after which his thigh gradually swelled over 6 months. Initially, an magnetic resonance imaging (MRI) diagnosed the condition as a hematoma. A surgeon performed an exploratory procedure and drainage without obtaining cultures or conducting a histopathological exam. Two weeks later, the site became infected, necessitating a second surgery based on radiological findings suggesting an infected hematoma. Deep tissue cultures grew Acinetobacter baumannii. Radiographs of the thigh showed air in soft tissues. The patient was referred to our institute suspecting gas gangrene. At the time of presentation, MRI showed a heterogeneous mass, leading to consultation with an orthopedic oncologist. Intraoperative frozen section analysis indicated a spindle cell neoplasm. The orthopedic oncosurgery team proceeded with en-masse excision, followed by additional debridement using vacuum-assisted closure. Enterobacter cloacae was isolated from deep tissue cultures, likely explaining the presence of gas pockets observed in soft tissues. Subsequently, a wide excision of the sarcoma was carried out, with skin grafting to cover the wound. Seven months later, the patient was undergoing chemotherapy for pulmonary metastases, with the surgical site showing no signs of infection. The patient succumbed to the disease 12 months after initial presentation at our institution, with metastasis being the cause of death.

Conclusion: Healthcare professionals should exercise heightened caution when managing post-traumatic intramuscular hematomas. Although MRI results can aid in diagnosis, it is vital to consider them alongside clinical findings. To conclusively exclude the possibility of cancer, a biopsy followed by histopathological analysis is necessary.