The Undifferentiated Carcinoma That Became a Melanoma: Re-biopsy of a Cancer of an Unknown Primary Site

A Case Report

Oluf Dimitri Røe; Sissel Gyrid Freim Wahl


J Med Case Reports. 2017;11(82) 

In This Article


Currently, with the advent of targeted treatment and immunotherapy, identifying molecular subtypes may be of benefit for several cancer types. Immunotherapy, by ipilimumab, a fourth-line treatment, induced a complete and durable response after recurrence and progression on chemoradiotherapy and two BRAF inhibitors. Moreover this patient had clinical benefit with paclitaxel-carboplatin on what was perceived as an undifferentiated carcinoma, which became resistant when transformed to a S100-positive melanoma.

In conclusion, molecular screening in the primary biopsy and re-biopsy of the recurrence may be of clinical value in CUP, where evaluations with a broad spectrum of immunohistochemical and molecular analyses are necessary.