Case report of high-grade pleomorphic sarcoma (rhabdomyosarcoma): a missed diagnosis in the non-healing post-traumatic wound of the elderly

Abstract

Rhabdomyosarcoma (RMS) is known to be common childhood soft tissue sarcoma (STS). RMS is infrequent in adults. STS constitute <1% of all adult solid malignant sarcomas and RMS accounts for 3% of all STS. The tumor is divided into three main subtypes-embryonal, alveolar, and pleomorphic (most common in adults). The most common primary sites are extremities. It’s an aggressive lesion with a high rate of metastasis. The patient presented with a non-healing wound over a posterior-medial aspect of the right leg with features suggestive of cellulitis. The patient gave a history of fall 5 months ago for which he took treatment at a local doctor, he continued to have severe pain for which an orthopedic opinion was taken and advised conservative management for an un-displaced fracture of the fibula. He later developed swelling over the lower-middle part of his right leg 3 months ago for which an ultrasound was done suggestive of a large amount of fluid suspicious of hematoma secondary to A-V malformation, an attempt for drainage of fluid was made leading to an evacuation of blood clots further procedure was abandoned and the patient transferred to our center. CT-angio demonstrated it as a heterogeneously attenuating solid cystic lesion. After appropriate consents-wound exploration was done with the evacuation of soft gelatinous material with pus discharge and blood clots. HPE-suggestive of high-grade pleomorphic rhabdomyosarcoma. The patient was advised amputation but denied any further treatment. Post-operative recovery was uneventful with no recurrence for the first 6 months after which the patient did not follow up. Post-traumatic mass at extremities should be evaluated with a high index of suspicion of STS. In case of doubt, either a preoperative biopsy or an intraoperative frozen section is a safe practice.