Diagnostic Criteria in Intraepithelial Pagetoid Neoplasms: A Histopathologic Study and Evaluation of Select Features in Paget Disease, Bowen Disease, and Melanoma In Situ.

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.

Reticulin immunostaining revisited.

Introduction: Reticulin staining has been suggested as an inexpensive tool in the differential diagnosis of melanoma versus benign nevi. In the present study, reticulin immunostaining patterns in malignant melanomas, benign intradermal nevi, and blue nevi were observed. The concordance in evaluation of the pattern between observers was also done.