Lepromatous leprosy, melanoma, and basal cell carcinoma: clinical-histopathologic association

Abstract

Cutaneous neoplasms frequently occur in leprosy, but there are few reports of the coexistence of leprosy and basal cell carcinoma in the same lesion. This case reports a 49-year-old male with an ulcerated plaque on the right lateral nasal wall, bright papules on the sternal region, and a blackened plaque on the right temporal region. The nasal and temporal lesions were diagnosed by histopathology as basal cell carcinoma and melanoma, respectively. The sternal lesions were excised with the repair of the “dog ear” which histopathological examination showed macrophages in the dermis parasitized with acid-fast bacilli, confirming the diagnosis of lepromatous leprosy with Fite-Faraco staining. This case report highlights the importance of referring the dog-ear specimen for histopathologic analysis.

Basal cell carcinoma associated with non-neoplastic cutaneous conditions: a comprehensive review

“…Microscopic evaluation of the dog ears showed numerous Fite-Faraco positive staining bacilli in the dermis, establishing the diagnosis of lepromatous leprosy in the same lesion as the sternal BCC. Subsequent examination of the patient revealed multiple cutaneous stigmata of lepromatous leprosy: ciliary madarosis, rarefaction of the distal eyebrows, ear skin thickening, and bilateral thickening of the ulnar nerve [124].…”

“…Although it has been a consideration that lepromatous leprosy-associated immunosuppression may have been an etiologic factor in the occurrence of the BCC, this is unlikely since the Mycobacterium leprae-associated immune response is specific for the mycobacteria and not related to the development of BCC. Hence, the large number of Mycobacterium leprae bacilli in patients with lepromatous leprosy probably accounts for the coexistence of the mycobacteria and the BCC in the same lesion [122][123][124].…”

“…The presence of systemic infections, such as leprosy and lupus vulgaris, in BCC tumor specimens is also likely to be coincidental. The altered immune response in patients with leprosy is specific to Mycobacterium leprae and is not related to the development of BCC [124]. Also, the evaluation of normal-appearing skin not only patients with lepromatous leprosy with its high bacterial load but also in individuals with other types of leprosy demonstrates organisms.…”