Abstract:

A 67-year-old female farmer presented with a painless dark-erythematous, green bean-sized nodule on the left side of her head for 5 years. The nodule gradually grew and extended to the left temple. Three months prior to the presentation, the lesion began to enlarge rapidly and ulcerate. Histopathology of the lesion revealed a diagnosis of basal cell carcinoma. Brown hypha, spores, and blastospores were observed between cancer cell nests and in necrotic tissues. Culture of biopsy materials grew moist, glistening, olivaceous-black or dark yeast-like colonies, with gray fluffy hyphae at the margin. Slide culture showed brown branched and septate hypha, with spinate conidiophores arising terminally or laterally at right angles. There were rhino-protuberances at the tip of conidiophores together with clumps of smooth, oval microconidia at the top of or around the conidiophores, and many clear annellations were observed at the distant end of conidiophores. The strain was identified as Exophiala spinifera and confirmed genetically. The patient was diagnosed as phaeohyphomycosis caused by Exophiala spinifera superimposed on basal cell carcinoma based on the clinical manifestations, histopathological and mycological examinations, as well as DNA sequencing results. Clinical cure was achieved after management with oral itraconazole and 10-session photodynamic therapy. No recurrence was noted during 1-year follow-up.

Key words: Phaeohyphomycosis, basal cell carcinoma, Photodynamic therapy, Itraconazole