Dermal Squamomelanocytic Tumor: Neoplasm of Uncertain Biological Potential

Mirsad Dorić; Svjetlana Radović; Suada Kuskunović; Ajna Hukić; Mirsad Babić; Ivana Tomić; Ivan Selak

doi:10.17305/bjbms.2008.2972

Authors

Mirsad Dorić Institute of Pathology, Faculty of Medicine, University of Sarajevo
Svjetlana Radović Institute of Pathology, Faculty of Medicine, University of Sarajevo
Suada Kuskunović Institute of Pathology, Faculty of Medicine, University of Sarajevo
Ajna Hukić Institute of Pathology, Faculty of Medicine, University of Sarajevo
Mirsad Babić Institute of Pathology, Faculty of Medicine, University of Sarajevo
Ivana Tomić Institute of Pathology, Faculty of Medicine, University of Sarajevo
Ivan Selak Institute of Pathology, Faculty of Medicine, University of Sarajevo

DOI:

https://doi.org/10.17305/bjbms.2008.2972

Keywords:

squamomelanocytic, squamous cell carcinoma, malignant melanoma

Abstract

We report a case of exceedingly rare cutaneous neoplasm with histological features of malignancy and uncertain biological potential. The nodular, darkly pigmented facial tumor with central exulceration, size 12x10x7 mm, of the skin 61-year-old man preauricular left was completely exised.

Histologically tumor consists of atypical squamous cells, which express signs of moderate to significant pleomorphism, mitotically active, with foci forming of parakeratotic horn cysts (“pearls”). Characteristically tumor also consists of large number of atypical melanocytes with multifocal pattern, inserted between atypical squamous cells, and which contain large amount of dark brown pigment melanin. Immunohistochemically, squamous cells stain positively with keratin (CK116), melanocytes were stained with S -100 protein, HMB 45, and vimentin, but failed to stain with CK 116.

To our knowledge this is the sixth reported case in world literature. The follow-up time of four years no evidence of recurrence or metastasis, similar all reported cases, but it is too short period in estimation to guarantee a benign course. However, it appears that this group of neoplasm may have different prognosis from pure squamous carcinoma or malignant melanoma.