A case of IgA pemphigus with acantholysis in oral mucosal lesions.

IgA pemphigus is an autoimmune bullous disease caused by anti-keratinocyte cell surface IgA autoantibodies. Mucous membrane involvement is rare in IgA pemphigus. We report a case of IgA pemphigus with oral mucosal lesions, in which acantholysis was pathologically confirmed. A 31-year-old woman presented with skin erythema with small pustules and oral mucosal erosions. Histopathological examination of the erosions on her oral mucosa and papules on her back revealed acantholysis and intraepidermal infiltration of neutrophils. Direct immunofluorescence tests showed intercellular deposition of IgA, but not IgG, mainly in the lower, but not entire, layer of the epidermis. C3 was linearly present in the basement membrane zone (BMZ), but not in the intercellular space. Enzyme-linked immunosorbent assay revealed that both anti-desmoglein (Dsg) 3 IgA and IgG were positive. Neither IgA nor IgG against desmocollin 1-3 were detected. This case was clinically and histologically compatible with IgA pemphigus, but immunologically anti-BMZ autoimmunity was additionally observed. IgA pemphigus is classified into two major types: subcorneal pustular dermatosis type and intraepidermal neutrophilic dermatosis type. This case was not typical in terms of rarely observed oral lesions and predominant deposition of IgA in the lower layer of the epidermis. Instead, this case could be considered a rare subtype of IgA pemphigus, IgA-pemphigus vulgaris. Oral lesions in IgA pemphigus may be clinical clue of having anti-Dsg3 IgA that cannot be routinely examined.

Successful treatment of onychomatricoma with minimally invasive surgical procedures based on its pathogenesis: A case report.

Onychomatricoma is a rare, fibroepithelial tumor of the nail. Although it is benign, unnecessary and excessive treatment, such as extensive or total removal of the nail matrix, has been reported in the past. Recently, it was speculated that onychomatricoma is derived from onychomatricodermis, the dermal stroma of the nail matrix. Excision of the stromal rather than the epithelial component of the tumor is important. However, since the boundary between the normal and diseased stroma is usually unclear, minimal excision at the base of the tumor projection should be sufficient. We report a case of onychomatricoma and suggest a method of surgical treatment that would minimize postoperative deformity of the nail plate.

Role of androgen signaling in androgen receptor-positive extramammary Paget's disease: Establishment of organoids and their biological analysis as a novel therapeutic target.

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare intraepithelial adenocarcinoma that mainly affects the anogenital and axillary regions. Although its etiology has not been fully elucidated, there is evidence that androgen receptors (AR) are expressed in most cases of EMPD. However, the role of androgen signaling in the pathogenesis of EMPD remains unclear. OBJECTIVE: To evaluate the role of androgen signaling in tumor growth of AR-positive EMPD. METHODS: Patient-derived organoids were established and cultured from two AR-positive EMPD patients: one man and one woman. Cultured organoids were treated with androgen agonists and/or antagonists, then subjected to analysis of changes in organoid proliferation, as well as changes in androgen signaling pathway-specific genes. RESULTS: Organoid cultures were established from each EMPD sample. These organoids were immunohistologically and genetically identical to the original tumor. For each organoid sample, viable cell number increased in response to androgen exposure. The mRNA level of Fkbp5, a known AR target gene, increased in a concentration-dependent manner in organoids exposed to the synthetic androgen R1881. Conversely, the AR inhibitor darolutamide suppressed the viable cell number in a concentration-dependent manner. The mRNA expression levels of MKI67 and Fkbp5 were also suppressed by darolutamide. CONCLUSION: Our results indicate that androgen signaling is a key pathway involved in the growth of AR-positive EMPD. Therefore, androgen signaling inhibition may be a novel treatment option for EMPD patients who require systemic therapy.

Management and outcomes of hydronephrosis in patients with metastatic extramammary Paget's disease: A retrospective analysis.

Hydronephrosis in extramammary Paget's disease (EMPD) with distant metastasis (metastatic EMPD) has been observed in medical practice; however, its prognosis remains unclear. Retrospective analyses were performed to assess the management and outcomes of hydronephrosis in metastatic EMPD. During a follow-up of 44 patients with metastatic EMPD, 13 (30%) developed hydronephrosis. Ten (77%) of the 13 patients with hydronephrosis had impaired renal function (estimated glomerular filtration rate: <60 ml/min/1.73 m2 ), and ureteral stents were placed in every patient with impaired renal function. The stent was placed successfully in all 10 patients, and their renal function recovered within a median period of 7 days. Importantly, each of these patients continued chemotherapy, and none of them experienced stent failure. The median overall survival time (OS) in patients with metastatic EMPD and hydronephrosis (n = 13) was 7.8 months. Treatment for hydronephrosis was not a significant factor for OS, and median OS in patients who underwent ureteral stent replacement (n = 10) was 14.7 months. Collectively, our results indicate that hydronephrosis is relatively common, and ureteral stent placement should be considered in cases of metastatic EMPD with hydronephrosis to maintain renal function and continue chemotherapy toward a better prognosis.

Imatinib mesylate in combination with pembrolizumab in patients with advanced KIT-mutant melanoma following progression on standard therapy: A phase I/II trial and study protocol.

INTRODUCTION: Genetic alterations of KIT gene are known to be one of the major causes of melanoma. Those are more common in the mucous and acral subtypes and KIT is regarded as major oncogene in Asian melanomas, where the prevalence of these subtypes is high. Up to date, several clinical trials have been conducted to target KIT gene alterations in melanoma with unsatisfied efficacies. Imatinib mesylate, a small-molecule inhibitor of the KIT tyrosine kinase, provides a rapid but not durable clinical response in KIT-mutant melanoma. Meanwhile, recent basic and clinical evidence have revealed another aspect of KIT-targeted therapy, namely the enhancement of antitumor activity of immune checkpoint inhibitors. Herein, we designed clinical trial of co-administrating imatinib mesylate and pembrolizumab (anti-PD-1 antibody) to evaluate its safety and efficacy. METHODS AND ANALYSIS: This is an open-label, single-arm, phase I/II clinical trial involving Japanese patients with metastatic KIT-mutant melanoma that are refractory to standard therapy including anti-PD-1 therapy. Phase I study is a dose-escalation study comprising two dose levels of imatinib mesylate (200 and 400 mg/day, respectively) with fixed dose of pembrolizumab (200 mg every 3 weeks) to evaluate safety and tolerability and determine recommended phase II dose. The primary endpoint of the phase II study is the objective response rate after 4 cycles (3 weeks/cycle) of pembrolizumab and imatinib mesylate at the dose determined in phase I, based on RECIST version 1.1. A Simon's minimax two-stage design is employed to test the null hypothesis of a 5% response rate vs 30% alternative, which will be rejected when a lower confidence limit of two-sided 90% confidence interval of true response rate is over than threshold response rate. The secondary endpoints include progression free survival, overall survival, best overall response and incidence of adverse events. Totally, a target size of 22 patients will be expected. DISCUSSION: If this study shows efficacy and acceptable safety profile, it will contribute to the development of novel treatment option for patients with KIT-mutant melanoma that are refractory to standard therapy. TRIAL REGISTRATION: NCT04546074. Date of Registration: September 11, 2020 (https://clinicaltrials.gov/ct2/show/NCT04546074). Date of First Participant Enrollment: December 23, 2020.

Anti-PD-1 antibody therapy for epithelial skin malignancies: An investigator-initiated, open-label, single-arm, multicenter, phase II clinical trial (NMSC-PD1 Study).

INTRODUCTION: Malignant cutaneous epithelial tumors comprise various skin malignancies originating from the cutaneous epithelium, including cutaneous squamous cell carcinoma, basal cell carcinoma, and malignant cutaneous adnexal tumors. Treatment options are limited, as the rarity of these tumors, especially among Asians, renders well-controlled clinical trials extremely challenging to conduct. Thus, we designed a clinical trial to evaluate the efficacy and safety of the anti-programmed cell death-1 (PD-1) monoclonal antibody nivolumab in patients with metastatic cutaneous squamous cell carcinomas and other rare metastatic cutaneous epithelial tumors. METHODS AND ANALYSIS: This is an open-label, single-arm, multicenter, phase 2 clinical trial involving patients with metastatic malignant cutaneous epithelial tumors. Nivolumab (480 mg) will be administered intravenously every 4 weeks for a maximum of 26 doses. The primary outcome of the study will be the response rate based on response evaluation criteria in solid tumors, version 1.1. Assuming a null hypothesis of a response rate ≤5% and an alternative hypothesis of a 25% response rate, a minimum of 26 patients are required to achieve a 5% two-sided type I error and 80% power based on the exact binomial distribution. Finally, a target cohort size of 30 patients was determined as some patient dropout will be expected. DISCUSSION: This is the first phase 2 clinical trial evaluating the efficacy and safety of the PD-1 inhibitor nivolumab in Asian patients with metastatic malignant cutaneous epithelial tumors. The findings of the study will contribute to the development of novel treatment approaches for patients with rare cutaneous malignancies, which remains an unmet clinical need. TRIAL REGISTRATION: Registry number: jRCT 2031190048.

High-grade trichoblastic carcinoma arising through malignant transformation of trichoblastoma: Immunohistochemical analysis and the expression of p53 and phosphorylated AKT.

Trichoblastoma (TB) is a benign cutaneous adnexal neoplasm. The lesion typically presents as a slow-growing, solitary, well-circumscribed nodule measuring up to 3 cm in diameter. On rare occasions, TB causes malignant transformation into an aggressive form described as high-grade trichoblastic carcinoma. Four such cases have been reported to date; all were described as high-grade trichoblastic carcinomas. Here, we describe the case of a 72-year-old Japanese male patient with a rapidly enlarging subcutaneous tumor on his lower back, which was diagnosed as high-grade trichoblastic carcinoma. Histopathologically, the tumor featured both benign and malignant components, and a transition zone between these states was clearly evident. In the immunohistochemical analysis, a malignant component was positive for p53 and showed stronger staining of phospho-RAC-α serine/threonine-protein kinase (AKT) Ser473 in comparison with a benign component. These results suggest that loss of p53 function and activation of phosphatidylinositol 3-kinase-AKT signaling pathways played important pathogenic roles in malignant transformation of the present case.

Synergistic effects of interferon-beta and nivolumab in oral mucosal melanoma.

Mucosal melanoma is a rare aggressive cancer with a very poor prognosis. Clinical and pathological characteristics of mucosal melanoma differ from those of cutaneous melanoma and there are no established management guidelines for mucosal melanoma. Complete surgical excision is one of the most effective treatments for localized lesions, while targeted therapies and immunotherapies, such as monoclonal antibodies that target cytotoxic T-lymphocyte-associated molecule-4, and the programmed death (PD)-1/PD-ligand 1 pathway inhibitors, are treatment options for unresectable or metastatic lesions. Here, we describe the case of a patient with oral mucosal melanoma with multiple metastases. In our case, local injection of interferon (IFN)-ß with dacarbazine-nimustine-vincristine therapy provided antitumor effects on an invasive tumor on the upper gingiva. Nivolumab therapy produced complete remission of lymph node and bone metastases. In contrast, the remaining in situ portion of oral mucosal melanoma on the hard palate was refractory to IFN-ß monotherapy and nivolumab therapy. However, after administration of nivolumab, peritumoral injection of IFN-ß showed rapid therapeutic effects. Our case suggested that nivolumab upregulated the antitumor effects of IFN-ß, which induced the recruitment of CD8+ T cells into the tumor microenvironment contributing to the deletion of tumor cells. Combination therapy of IFN-ß and nivolumab may be a potential treatment option for patients with oral mucosal melanoma.

Sarcomatoid carcinoma arising in the congenital pigmented nevus after treatment with carbon dioxide snow freezing method.

We report a case of sarcomatoid carcinoma of the skin in a 63-year-old man who was treated with the carbon dioxide snow freezing method for a huge congenital pigmented nevus that extended from the right upper extremity to the right trunk during childhood. He had an exophytic red tumor on the nevus in the right upper extremity that grew slowly for 4 years and rapidly recently. Histological and immunohistochemical studies revealed both epithelial and mesenchymal malignancy in the same tumor. The epithelial component was composed of basaloid cells forming multiple nests with peripheral palisading, positive for keratins and BerEP4, implying basal cell carcinoma. The mesenchymal component was composed of spindle-shaped cells negative for keratins and positive for vimentin, suggesting sarcoma. This is, to our knowledge, the first report of sarcomatoid carcinoma arising in the primary pigmented nevus that had been treated by the carbon dioxide snow freezing method.