35007 An unusual clinical presentation of a squamous cell carcinoma mimicking mycetoma

Abstract

Mycetoma is a chronic granulomatous infection of subcutaneous tissue caused by bacteria or fungi. It is endemic to tropical areas and leads to tissue swelling, ulcerated nodules, and draining sinus tracts. We present the case of a patient with an atypical squamous cell carcinoma (SCC), whose clinical presentation was consistent with mycetoma. Our patient is a 39-year-old Guatemalan male without past medical history who presented with a 20-year history of nonresolving swollen and ulcerated lesions on his left buttock. Upon examination, he had a large, edematous, and indurated mass with multiple circular ulcers and sinus tracts draining yellowish, malodorous discharge. Punch biopsies were performed for histology and tissue cultures. Tissue cultures for bacteria, atypical mycobacteria, nocardia, actinomyces, and fungi only grew polymicrobial bacterial organisms for which he was treated with antibiotics and had minimal improvement. Unexpectedly, histology revealed a well-differentiated SCC, and a left inguinal lymph node biopsy was positive for SCC. A wide excision was performed and hematology/oncology and surgery departments are currently following the patient for further management. This case demonstrates the importance of including SCC in the differential diagnosis when there is clinical suspicion of a long-standing infectious process such as mycetoma, especially when dealing with areas of chronic inflammation. The development of SCC has long been associated with non-healing wound ulcers. Even when solely an infectious process is suspected, clinicians should perform biopsies for both tissue cultures and histopathology to ensure prompt diagnosis, since malignancies such as SCC have the potential to masquerade as an infection.