Faculty Bibliography

Onychopapilloma (OP) is a benign nail unit tumor of the distal nail matrix and nail bed that typically presents as solitary longitudinal erythronychia with distal subungual hyperkeratosis and focal onycholysis. Atypical OP is a newly recognized and evolving concept in dermatopathology. Herein, we present a histopathologically-proven atypical OP with a classic clinical appearance that developed during pregnancy. A 37-year-old Gravida two Para one woman presented with a red longitudinal band on the left thumbnail that appeared during the first trimester of an uncomplicated pregnancy. The lesion was asymptomatic; however, it was gradually increasing in size, prompting a longitudinal excisional biopsy of the lesion post-partum. Histopathologic evaluation of the nail unit revealed common features of an OP, including acanthosis and papillomatosis of the nail bed with focal matrix metaplasia. There were focal areas of cytologic atypia and mitotic figures with corresponding increased suprabasilar Ki-67 expression. The tumor was excised with Mohs micrographic surgery in one stage, and the resulting defect healed with secondary intention. No recurrence was observed at 6-month follow-up. This case expands the current literature on histopathologically-proven atypical OP and describes the novel occurrence during pregnancy.

BACKGROUND:Solid organ transplant recipients (SOTRs) face frequent advanced cutaneous malignancies, yet data guiding systemic therapy are limited. MATERIALS AND METHODS/METHODS:We conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses systematic review of immune checkpoint inhibitors (ICIs), talimogene laherparepvec (T-VEC), and Sonic Hedgehog Pathway Inhibitors (HPIs) for locally advanced or metastatic cutaneous squamous cell carcinoma, melanoma, Merkel cell carcinoma, and basal cell carcinoma in SOTRs, including a novel case from our institution. Outcomes included tumor response, graft rejection, and graft failure. RESULTS:Among 196 SOTRs treated with ICIs (101 cutaneous squamous cell carcinoma, 83 melanoma, 12 Merkel cell carcinoma), the overall response rate (ORR) was 39.3%, and lack of progression occurred in 58.0%. Graft rejection occurred in 36.9% and graft failure in 22.3%. A higher number of baseline immunosuppressive agents decreased odds of rejection (OR 0.55) and failure (OR 0.38). Tacrolimus was associated with reduced tumor response (OR 0.41), whereas mTOR-based regimens and cemiplimab were associated with fewer transplant rejection. T-VEC was reported in 10 SOTRs with an ORR of 90% and no graft rejection or failure. HPIs in six SOTRs with basal cell carcinoma demonstrated ORR of 83% without graft loss. CONCLUSION/CONCLUSIONS:ICIs provide antitumor activity but substantial graft-related risk, while T-VEC and HPIs show high response rates with no reported rejection.

Platelet-rich plasma (PRP) injections are an effective and increasingly utilized treatment for androgenetic alopecia; however, the delivery of concentrated growth factors raises theoretical concerns regarding cutaneous malignancy risk in chronically ultraviolet (UV)-exposed, hair-thinning scalps. In this article, the current hypotheses linking PRP to scalp skin cancer risk are reviewed, including potential oncogenic mechanisms, such as platelet-derived growth factor (PDGF)-mediated signaling, and protective effects, such as improved hair-mediated photoprotection and antiproliferative findings from related blood products, although direct PRP-specific data remain lacking. Overall, the available evidence supports PRP safety while underscoring the need for prospective studies, routine scalp surveillance, and patient counseling regarding photoprotection.

BACKGROUND:Data are limited regarding the performance of staging systems for non-head and neck cutaneous squamous cell carcinomas (non-HNCSCCs). OBJECTIVE:The aim of this study was to evaluate the performance of the Brigham and Women's Hospital (BWH) and American Joint Committee on Cancer 8th edition (AJCC8) staging system in predicting poor outcomes in non-HNCSCCs. PATIENTS AND METHODS/METHODS:Demographics, tumor features and stages, and outcomes for non-HNCSCCs were collected retrospectively from 11 institutions in two countries. Poor outcomes included local recurrence, metastasis, and disease-specific death; major poor outcomes excluded local recurrence. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), concordance index (c-index), and 3-year cumulative incidence were calculated. Cumulative incidence function (CIF) plots were created. RESULTS:9300 non-HNCSCCs were included. Ninety-five tumors (1%) resulted in major poor outcomes; 250 (2.7%) resulted in poor outcomes. The rate of local recurrence was 1.9%, and the rate of nodal metastasis was 0.74%. Major poor outcomes were predicted with sensitivities 0.48/0.49, specificities 0.98/0.96, PPVs 0.17/0.13, NPVs 0.99/0.99, and c-indices 0.73/0.74 for BWH/AJCC8. Poor outcomes were predicted with sensitivities 0.24/0.26, specificities 0.98/0.97, PPVs 0.22/0.17, NPVs 0.98/0.98, and c-indices 0.61/0.61 for BWH/AJCC8. CONCLUSIONS:Both systems performed similarly in predicting poor outcomes in non-HNCSCCs. Specificity and NPV were high, sensitivity and PPV were low, and c-indices were moderately high. As the c-indices were comparable to those seen in the HNCSCC literature, it is reasonable to use the BWH and AJCC8 staging systems for tumors located off the head and neck. However, further refinement of CSCC staging systems is needed to improve prognostication.