Stratified mucin-producing intraepithelial lesion (SMILE) and invasive stratified mucin-producing carcinoma (ISMC) are recently described cervical and penile lesions. We report an unusual case of mixed variant of penile squamous cell carcinomas with warty, usual and mucoepidermoid SMILE/ISMC features.
A 62-year-old Japanese man had a glans penis lesion of one and a half years duration, suggesting malignancy. Partial penectomy and left inguinal lymphadenectomy were performed. Pathological evaluation revealed a mixed squamous cell carcinoma with warty, mucinous and usual features. The mucinous component resembled mucoepidermoid carcinoma (MEC) and SMILE/ISMC. Glandular differentiation was absent. All the diverse tumour components were negative for p16 which was confirmed by negative human papillomavirus genotyping. The mucinous component was diffusely positive for cytokeratin 7 and largely negative for cytokeratin 5 and p63. Fluorescent in situ hybridization did not detect rearrangement in the MAML2 or EWSR1 genes. The tumour was pathologic stage pT2, pN1 (AJCC prognostic stage group IIIA) and was disease-free 26 months after surgery.
The lack of glands in the mucinous areas suggested that MEC should be separated from adenosquamous carcinoma (ASC) Penile SMILE/ISMC may occur without dependence on HPV status. Further studies will be necessary to determine the pathogenesis and definition of penile SMILE/ISMC, the presence of true MEC arising from the glans penis, and the clinicopathological differences of penile ASC, MEC, and SMILE/ISMC. Herein, we refer to the SMILE-like penile lesion as "mucinous penile intraepithelial neoplasia". This article is protected by copyright. All rights reserved.
Histopathology. 2017 Nov 16 [Epub ahead of print]
Kenji Yorita, Naoto Kuroda, Takushi Naroda, Masato Tamura, Chisato Ohe, Mukul Divatia, Mahul B Amin, Antonio L Cubilla, Dimitry V Kazakov, Ondrej Hes, Michael Michal, Michal Michal
Department of Diagnostic Pathology, Japanese Red Cross Kochi Hospital, 2-13-51, Shinhonmachi, Kochi, 780-8562, Japan., Department of Urology, Japanese Red Cross Kochi Hospital, 2-13-51, Shinhonmachi, Kochi, 780-8562, Japan., Department of Pathology & Laboratory Medicine, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA, 90048, USA., Department of Pathology and Laboratory Medicine, University of Tennessee Health Sciences Center, Memphis, TN, 38163, USA., Instituto de Patologia e Investigacion, Universidad Nacional de Asuncion, Asuncion, Paraguay., Department of Pathology, Charles University, Medical Faculty and, Charles University Hospital Plzen, Alej Svobody 80, 304 60, Pilsen, Czech Republic.