Subcutaneous porocarcinoma clinically presenting as a soft tissue tumor.
Porocarcinoma is a rare malignancy with glandular adnexal differentiation. A 38-year-old Japanese man noticed a subcutaneous mass in right inguinal region about 20 years prior to being examined. Radiological examinations demonstrated the mass, 11 × 10 cm in size, was in the subcutaneous fat tissue. Recently, the mass grew rapidly, and it was biopsied by an orthopedist based on clinical diagnosis of primary soft tissue tumor. Histopathological examination of the resected specimens also revealed that the tumor lacked involvement to the skin. Microscopically, the tumor was mainly composed of poroid cells with partially obvious squamous differentiation, accompanied by focal ductal structures immunoreactive for CEA and EMA. The tumor contained a low-grade area consisting of poroid cells and high-grade area with squamous differentiation. This histopathological heterogeneity suggested malignant transformation from poroma. The patient had the tumor in almost same size over the period of 20 years, which is the longest in the previous reports. This unique case of subcutaneous porocarcinoma is reported.
Department of Pathology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Tadao
T
Nakazawa
Department of Pathology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Tetsuo
T
Kondo
Department of Orthopaedic Surgery, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Eiichi
E
Sato
Department of Radiology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Utaroh
U
Motosugi
Department of Pathology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Dongfeng
D
Niu
Department of Pathology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Kunio
K
Mochizuki
Department of Pathology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Tomonori
T
Kawasaki
Department of Pathology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Tetsu
T
Yamane
Department of Pathology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Yamanashi, Japan.
Ryohei
R
Katoh
D000328:Adult; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D003937:Diagnosis, Differential; D057090:Eccrine Porocarcinoma / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D008297:Male; D012983:Soft Tissue Neoplasms / Q000175:diagnosis / Q000473:pathology*; D040521:Subcutaneous Tissue / Q000473:pathology*
adnexal neoplasm; histological heterogeneity; locating in the subcutaneous tissue