Title : Malignant transformation of nevus sebaceous to basal cell carcinoma in a 61-year old Filipino male: A case report
Abstract:
Nevus sebaceous (nevus sebaceus of Jodassohn, organoid nevus), is a benign dermatologic condi/on involving the pilosebaceous unit. It presents between birth and adolescence as hairless, yellow, waxy and verrucous plaques following a blaschkoid pacern and is most frequently seen on the head and neck. Secondary tumors have been reported in about 25% of affected individuals with syringocystadenoma papilliferum and trichoblastoma as the most common benign neoplasms. Studies indicate that the development of malignant neoplasm is very rare. The risk of Basal Cell Carcinoma (BCC) developing on a nevus sebaceous, is es/mated at only 0.8%.
This case report presents the case of a 61-year old Filipino man with a flesh to yellowish plaque located in the scalp, present from birth, on which a progressively enlarging and non-healing ulcera/on developed. Cutaneous examina/on showed a solitary, well-demarcated, round, 3 cm x 3 cm, erythematous nodule with purulent non-foul smelling, yellow discharge, areas of ulcera/on and bleeding on the leh parietal area of scalp. An incision biopsy was done revealing basaloid cells posi/ve for BER-EP4 and nega/ve for CK20 as well as CD10 confirming BCC, nodular and superficial types as well as NS. Mohs micrographic surgery repaired with mul/ple rhomboid flap was performed. The pa/ent demonstrated good postopera/ve wound healing and remained without complica/ons aher a follow-up period of 6 months. There are no signs of recurrence aher a year of monitoring.
The objec/ve of this report is to recognize early features that could suggest malignant growth in a nevus sebaceous. It is essen/al to know the usual morphologic changes of nevus sebaceus across /me so that unusual changes can raise suspicion for secondary tumors and possibly malignancy. This report highlights that while BCC is rare, it is s/ll important to consider in the differen/al diagnoses as a secondary tumor in nevus sebaceous.
