Abstract: Panfolliculoma (PF) is an uncommon benign follicular neoplasm exhibiting differentiation toward all components of a hair follicle. Several pathologic manifestations have been described in a limited number of cases. We studied 19 cases of PF to summarize the clinical parameters and to classify this unique neoplasm histopathologically. A study of the largest sample series of PF has been performed here. The lesions affect both genders after age 20. The head is the most common site of PF of all types. On microscopic examination, all cases demonstrated advanced follicular differentiation by showing cell components of infundibulum, isthmus, stem, bulb, and mesenchymal papilla. Based on the findings and various patterns in histopathology, we classified PF into 3 subtypes: nodular, superficial, and cystic. The superficial and cystic variants account for most of the cases in our study. The histopathologic differential diagnosis is also discussed for each subtype.
*Ackerman Academy of Dermatopathology, New York, NY; and
†Department of Dermatology, Tianjin Medical University General Hospital, Tianjin, China.
Reprints: Ying Guo, MD, Ackerman Academy of Dermatopathology, 145 East 32nd Street, 10th Floor, New York, NY 10016 (e-mail: yguo@dermpathdiagnostics.com).
S.-J. Shan did this work when he was a fellow in Ackerman Academy of Dermatopathology. Study concept and design (S.-J.S.). Y. Guo had full access to all of the data in the study and took responsibility for the integrity of the data and the accuracy of the data analysis.
The authors declare no conflicts of interest.
