Synchronous multiple primary malignancies or transdifferentiation?-A diagnostic challenge in a case of Xeroderma pigmentosum.

Journal: Indian Journal Of Pathology & Microbiology
Published:
Abstract

A diagnosis of synchronous tumors is always questionable when they show similar histology. We present a case of synchronous tumors, i.e. melanoma (MM) arising from the scalp and angiosarcoma (AS) from the cheek in a patient of Xeroderma pigmentosum (XP). The presence of melanin in AS of the cheek led to a differential diagnosis and a possibility of transdifferentiation of malignant melanoma in the first instance. Immunohistochemistry (IHC) was negative for melanoma markers (Melan A, SOX-10 & S 100) and positive for vascular markers (ERG, CD31 & CD34) ruling out transdifferentiation and concluding the cheek swelling as angiosarcoma. The presence of non-cutaneous malignancies is rare in XP and the presence of MM in a nearby site and the melanin pigment in the cutaneous malignancy mislead the diagnosis. The morphology of the tumor was the key which led to the further workup of the case.

Authors
Sandhyarani Kanna, Supriya Sandeepa, K Mukund, M Nirupama, K Bhargavi, Jessica Minal