Early Onset of Squamous Cell Carcinoma Arising From Tuberculosis Verrucosa Cutis

A 72-year-old man presented with a chronic scaly verrucous plaque over his right knee for nine months. The lesion was preceded by a well healed scar sustained five years back from a road traffic accident. He was given multiple courses of systemic antibiotic and antifungal medications but to no avail. A skin biopsy confirmed cutaneous tuberculosis. The area of plaque subsided significantly with antituberculosis treatment. However, during the second month of treatment, a new onset of a red fleshy granulating growth developed on the pre-existing site. A repeat skin biopsy revealed squamous cell carcinoma (SCC). He was subsequently referred for surgical excision. This is presumably the first reported case of SCC arising from tuberculosis verrucosa cutis. While most malignant transformations from tuberculosis has been thought to develop after a long period of time (usually more than twenty-five years), this case report showed that it may also occur within a short period of time. Awareness on this condition is important because any delay in diagnosis and treatment may have detrimental consequences.