2017 Volume 31 Issue 3 Pages 261-267
A small, red nodule developed on the metatarsophalangeal joint of the left index finger in 2007 and was surgically resected in November 2013. It was histopathologically diagnosed as Bowen's disease. The patient was admitted to a regional hospital in May 2015 due to tumor recurrence at the operated site. Because the tumor rapidly expanded despite liquid nitrogen therapy, the patient consulted our hospital in August 2015. The tumor was surgically resected with a 2 cm surgical margin. Histopathological study revealed that the erythematous part showed findings of Bowen's disease and squamous cell carcinoma with differentiation into the skin appendages (sweat apparatus and hair follicle). In contrast, the mass part showed sarcoma-like findings with osteoblastic differentiation. We diagnosed the tumor as metaplastic carcinoma (carcinosarcoma) (CS) because the tumor consisted of 2 different parts : epithelial and sarcomatous. Cases of CS occurring originally in the skin have been rarely reported. Thus, we report herein a case of CS and a literature review.[Skin Cancer (Japan) 2016 ; 31 : 261-267]
