Amira Elbendary1, Ruzeng Xue, Manuel Valdebran, Kara Melissa T Torres, Kruti Parikh, Inas Elattar, Eun Ji Kwon, Dirk M Elston. 1. *Demonstrator at the Dermatology Department, Kasralainy Faculty of Medicine, Cairo, University, Egypt; †Visiting Research Fellow, Ackerman Academy of Dermatopathology, New York, NY; ‡Attending Dermatologist, Department of Dermatology, Dermatology Hospital of Southern Medical University, Guangdong Provincial Dermatology Hospital, China; §Junior Specialist, Department of Dermatology, University of California, Irvine, CA; ¶Attending Dermatologist, Department of Dermatology, Jose R. Reyes Memorial Medical Center, Manila; ‖Medical Student, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ; #Professor of Biostatistics, Department of Biostatistics and Epidemiology, National Cancer Institute, Cairo University, Cairo, Egypt; **Dermatopathologist, Dermpath Diagnostics New York, Port Chester, NY; and ††Professor and Chairman, Department of Dermatology and Dermatologic Surgery, Medical University of South Carolina, Charleston, SC.
Abstract
BACKGROUND: Paget disease, Bowen disease, and malignant melanoma in situ are intraepidermal neoplasms, characterized by the presence of pagetoid scatter of atypical cells in the epidermis. This study reviewed the frequency of select histologic criteria to validate their usefulness in the histologic distinction between these entities. METHODS: One hundred forty-four specimens with the diagnosis of Bowen disease, 144 specimens with Paget disease (mammary and extramammary), and 144 specimens with malignant melanoma in situ were examined microscopically to define frequencies of select histologic criteria present in each disease. RESULTS: Comparison between mammary Paget and extramammary Paget disease showed no significant differences in the features studied. Crushing of basal keratinocytes, presence of atypical cells in the corneum, and presence of large cells with amphophilic cytoplasm were significantly noted in Paget disease. Transition between the atypical clear cells and surrounding keratinocytes was absent in all cases of melanoma in situ and in 87 (60.4%) cases of Paget disease, but it was significantly associated with Bowen disease (98.6%). Dyskeratotic cells were significantly associated with Bowen disease cases. CONCLUSION: Our study demonstrated a practical histologic approach to differentiate between intraepidermal pagetoid neoplasms. Careful histologic study of the proposed criteria may reduce reliance on immunohistochemical stains.
BACKGROUND: Paget disease, Bowen disease, and malignant melanoma in situ are intraepidermal neoplasms, characterized by the presence of pagetoid scatter of atypical cells in the epidermis. This study reviewed the frequency of select histologic criteria to validate their usefulness in the histologic distinction between these entities. METHODS: One hundred forty-four specimens with the diagnosis of Bowen disease, 144 specimens with Paget disease (mammary and extramammary), and 144 specimens with malignant melanoma in situ were examined microscopically to define frequencies of select histologic criteria present in each disease. RESULTS: Comparison between mammary Paget and extramammary Paget disease showed no significant differences in the features studied. Crushing of basal keratinocytes, presence of atypical cells in the corneum, and presence of large cells with amphophilic cytoplasm were significantly noted in Paget disease. Transition between the atypical clear cells and surrounding keratinocytes was absent in all cases of melanoma in situ and in 87 (60.4%) cases of Paget disease, but it was significantly associated with Bowen disease (98.6%). Dyskeratotic cells were significantly associated with Bowen disease cases. CONCLUSION: Our study demonstrated a practical histologic approach to differentiate between intraepidermal pagetoid neoplasms. Careful histologic study of the proposed criteria may reduce reliance on immunohistochemical stains.