An unusual case of nasal chromoblastomycosis degenerating into squamous cell carcinoma from a nonendemic region

Latifa Mtibaa,Kahena Jaber,Refka Frioui

doi:10.7241/ourd.20214.16

Abstract

Chromoblastomycosis (CBM) is a granulomatous mycosis rarely described outside tropical countries. Degeneration into squamous cell carcinoma (SCC) is its most serious complication. We report the first case of nasal CBM degenerating into SCC. In 2006, a sixty-year-old male presented himself with an infiltrated plaque on the right thigh. The diagnosis of CBM was confirmed by the presence of fungal elements. In 2019, the patient had developed a mass coming from the right nasal cavity. It had rapidly involved the nasal dorsum. An ulcer-budding nasal tumor and an elevated erythematous and verrucous plaque on the thigh were noted. A biopsy revealed a granulomatous dermis with fungal elements. Other nasal biopsy fragments showed differentiated SCC. A fungal culture inoculated with tissue from both lesions showed dark colonies. The diagnosis of nasal CBM with SCC degeneration was reached. The patient presented asymptomatic endonasal CBM that had slowly evolved and recently degenerated.

Highlights

Chromoblastomycosis (CBM) is a slowly progressive granulomatous mycosis of the skin and subcutaneous tissue caused by inoculation of dematiaceous fungi mainly on the lower limbs
We report an unusual case of CBM from Tunisia, a nonendemic area, occurring in a distant site from the original lesion and degenerating into squamous cell carcinoma (SCC)
In 2006, a sixty-year-old healthy male from north Tunisia presented himself to our dermatology department with an infiltrated 6 × 5 cm erythematous plaque on the right thigh

Summary

INTRODUCTION

Chromoblastomycosis (CBM) is a slowly progressive granulomatous mycosis of the skin and subcutaneous tissue caused by inoculation of dematiaceous fungi mainly on the lower limbs This infection occurs in tropical and subtropical regions, but there have been several case reports from temperate regions. We report an unusual case of CBM from Tunisia, a nonendemic area, occurring in a distant site from the original lesion and degenerating into SCC. A microscopic examination of the colonies revealed cylindrical septate hyphae, and conidiophores swollen at their termination carrying ovoid conidia suggestive of the Fonsecaea pedrosoi species (Fig. 4e). From these features, the diagnosis of nasal CBM with SCC degeneration was reached.

DISCUSSION

Lower left limb and back

Findings

CONCLUSION