Lichenoid reactions are one of the most frequently observed toxicities with anticancer agents and, recently, a rapid emergence of immunotherapies in oncology has hastened the need to better characterize their unique toxicity profiles, particularly for less common skin toxicities, including anogenital lichen sclerosus et atrophicus (LSA). This case series describes four patients with advanced cancer (one melanoma, two lung cancers, and one kidney tumor) developing LSA lesions while receiving an immunotherapy. Medical records from 2017 to 2020 were retrospectively reviewed. Two patients received pembrolizumab, anti-programmed cell death-1 (PD-1), one nivolumab, anti-programmed cell death-1 (PD-1), and one ipilimumab, an immune checkpoint inhibitor. LSA emerged after a median of 3 months (range, 2-4 months) from starting immunotherapy. All LSA cases were grade 2. Three cases occurred on the penis and one case on the anus. All patients improved after a specific treatment for LSA, and no LSA-related antineoplastic treatment interruption/life-threatening condition were reported. To date, this is the first case series of LSA lesions associated with immunotherapy. Early LSA recognition and management is helpful in cancer patients on immunotherapy allowing a long survival and treatment response.

BACKGROUND: Hidradenoma papilliferum is a rare benign neoplasm arising from apocrine glands. It occurs commonly on the anogenital region of middle-aged women. It usually presents as a slow growing, solitary asymptomatic, skin colored or red nodule less than 1 cm in diameter.
METHODS: The case is a 38-year-old, white woman who presented with a painful nodule occurring within a month in the himenal region of the posterior vaginal introitus. The nodule was excisied and the histology revealed a hidradenoma papilliferum. The diagnosis and treatment of hidradenoma papilliferum is possible with surgical removal and histopathological evaluation of nodules.
CONCLUSIONS: When an adult woman presents with a noduler lesion in the anogenital area, sexually transmitted diseases and other benign and malignant vulvar lesions, as well as malignant transformation is very rare but,should be kept in mind; however because it has been reported and long-term clinical follow-up is suggested.

Extramammary Paget disease (EMPD) is a rare neoplasm. The clinical case of a 55-year-old man with a two-year history of a pruritic, painless erythematous skin rash on the inguinal region and scrotum is described. After a delay due to improper diagnosis and improper treatments, the patient came to the attention of the Division of plastic surgery. He underwent a punch biopsy and the pathology report came back as EMPD. Surgical excision was carried out, and an abdominal advancement cutaneous flap was performed for the defect repair. This is the first description of a reconstruction after surgical removal of inguinal EMPD with a flap of this type and we think that this type of treatment can be useful and reliable for disease localization in the groin area, especially for patients that present an excess of abdominal skin.

BACKGROUND: Papular acantholytic dyskeratosis (PAD) of the anogenital/genitocrural area is described as a rare distinct clinicopathological entity known to dermatopathologists, although its characteristic histopathologic pattern resembles both Hailey-Hailey disease and Darier disease. The objective of this study is to describe the clinical characteristics, histopathologic features and response to treatment of PAD.
METHODS: We report in detail six cases of PAD. A literature search of the keyword \'papular acantholytic dyskeratosis\' was performed on Google scholar and PubMed, 21 cases of this entity were found. A total of 27 patients including our six cases are reviewed in this study.
RESULTS: The mean age at diagnosis was 38.8 years with a male to female ratio of 0.8 : 1. Clinically, papular lesions (55.6%) are the typical manifestation of PAD, and the anogenital area (63%) is the most commonly involved site. Lesions were resistant to topical steroids, subcutaneous interferon and antibiotics while one case showed complete resolution of the lesions after retinoid therapy. Laser therapy showed good results in one case. None of the patients had spontaneous remission.
CONCLUSIONS: Awareness of the clinicopathological hallmarks herein may be important to avoid underdiagnosis of PAD and may contribute to understanding the pathogenesis of this rare disease.

We present a case of verruciform xanthoma ((VX) of the penis in an elderly man in whom an asymptomatic papule on his foreskin was noted during a routine clinical examination. VX is a rare, benign condition with a predilection for the oral cavity and clinically presents as isolated, painless mucosal lesions with a verrucoid surface. Accurate diagnosis is important in avoiding aggressive surgical management of this relatively rare condition.