Analysis of surgical margins and prognostic factors in dermatofibrosarcoma protuberans after wide local excision: A multicenter study of 116 Japanese patients.

Cutaneous dermatofibrosarcoma protuberans (DFSP) is a fibrohistiocytic tumor characterized by a high risk of local recurrence but a low risk of metastasis. Wide local excision (WLE) has been an important treatment option, but its clinical outcomes and safety have not been thoroughly evaluated in previous reports. The aim of this study was to determine appropriate surgical margins (deep and lateral) and prognostic factors associated with recurrence-free survival (RFS) of DFSP. A database collected by two dermatology departments in Japan was retrospectively reviewed to identify 116 patients with DFSP who underwent complete resection with WLE between 1994 and 2021. Sixty-one men (53%) and 55 women (47%) were included in our cohort. The primary sites of DFSP were as follows: 11 head and neck (9%); seven face (7%); 12 upper extremities (10%); 20 lower extremities (17%); and 66 trunk (57%). There were 103 cases (89%) of primary DFSP and 13 cases (11%) of recurrent DFSP. Total 10-year RFS was 96.6%. There were significant differences in RFS by tumor size (median size: 3 cm), disease status (primary versus recurrent DFSP), and fibrosarcomatous change (positive versus negative) (all p < 0.05). Two patients (1.7%) with buccal or head lesions had positive deep margins. In all cases, the lateral margin was negative at the postoperative evaluation. Tumor size, disease status, and fibrosarcomatous change are important risk factors for recurrence. Both face and head-neck lesions were more likely to have positive deep margins than other anatomic areas in DFSP. Although this study was limited by its retrospective design, a narrow 2-cm lateral margin is especially considered for low-risk patients.

Real-world efficacy and safety of BRAF-targeted therapy for patients with advanced melanoma: A single-center retrospective study in Japan.

Most clinical trials investigating targeted therapies for patients harboring BRAF V600 mutations have included mostly White patients, and data for Asian patients are scarce. Although there are several retrospective studies in Japanese patients, they have investigated only the dabrafenib + trametinib regimen, and have had a short follow-up period. We conducted a single-center retrospective study to update previous studies and compare the outcomes with those in White patients. We analyzed 89 patients who received dabrafenib + trametinib or encorafenib + binimetinib, including 11 who received both treatment regimens. The overall response rate was 79.8%, with complete response in 25 patients (28.1%) and partial response in 45 patients (51.7%). The median progression-free survival was 13.7 months, and the median overall survival was 32.9 months. The 3-year progression-free and overall survival rates were 31.8% and 47.9%, respectively. Although the two regimens showed no significant differences in efficacy, their safety profiles differed, as reported in clinical trials. Therefore, the most frequent adverse event associated with the dabrafenib + trametinib regimen was pyrexia (61.3%) and that of encorafenib + binimetinib was blurred vision (32.0%). Switching directly to another targeted therapy after progressive disease showed no clinical response; however, rechallenge followed by immune checkpoint inhibitor therapy showed a certain response. As a prognostic factor, performance status was associated with progression-free survival, and performance status, serum lactate dehydrogenase level, and dose interruption were associated with overall survival in the multivariate analysis. Real-world data on targeted therapy for patients with melanoma in Japan suggest that both dabrafenib + trametinib and encorafenib + binimetinib show similar efficacy and safety in Asian and White patients.

Long-term survival with systemic therapy in the last decade: Can melanoma be cured?

Immune checkpoint inhibitors have been shown to prolong survival of patients with several types of cancer, and the finding was first established in melanoma. Previously, systemic therapy for advanced melanoma aimed only at tumor control and palliation of symptoms. However, in recent years, some patients who received systemic therapy have achieved a complete response and survived without continuous treatment for more than several years. This review discusses the long-term survival rates achieved with currently used systemic therapies and their future perspectives. Long-term survival is currently most likely to be achieved with the use of the standard-dose combination of nivolumab plus ipilimumab, however, this regimen is associated with a high frequency of serious or persistent immune-related adverse events. Several new anti-PD-1-based combination therapies with a better risk-benefit balance are currently under development. Although the acral and mucosal subtypes tend to be less responsive to immune checkpoint inhibitors, anti-PD-1-based combination therapy should continue to be investigated for these subtypes owing to its potential for better long-term survival. With the development of efficacious immunotherapy and targeted therapy, it is important to determine the optimal duration of systemic therapy to avoid unnecessary health and financial burdens as well as to improve efforts to support long-term cancer survivors. As the goal of systemic therapy shifts from tumor control to long-term survival, in future clinical trials, long-term clinical outcomes should be evaluated to assess the benefits of novel agents.

Recent treatment and prognosis in 643 patients with extramammary Paget's disease.

Information about extramammary Paget's (EMPD) treatment is limited because of the rarity of the disease. The prognosis differs between in situ EMPD and invasive EMPD; therefore, therapy should be planned according to the disease stage. We collected data on 643 EMPD cases treated between 2015 and 2019 in Japan and assessed recent trends in EMPD treatment and prognosis based on the EMPD-oriented TNM staging. Among the 643 patients, 317 had stage 0 (49.3%), 185 had stage I (28.8%), 51 had stage II (7.9%), 18 had stage IIIA (2.8%), 48 had stage IIIB (7.5%) and 24 had stage IV (3.7%) disease. Each stage showed a distinct survival curve, with the exception of stages II and IIIA. Curative surgery was most common in patients with stage 0-III disease. Chemotherapy was the first-line therapy, mainly in patients with stage IIIB and IV disease, most commonly with docetaxel (DTX), followed by DTX + tegafur gimeracil oteracil potassium (TS-1) and TS-1. Patients with local disease exhibited a 4.4% recurrence rate. Univariate analysis revealed no prognostic differences according to age, sex or primary tumour site. SLNB was not related to disease-specific survival. In multivariate analysis, female sex significantly predicted local relapse in stage 0-I (HR 3.09; 95% CI, 1.13-8.43), and initial treatment with curative surgery was significantly protective in terms of disease-specific survival in stage II-IIIA (HR, 0.17; 95% CI, 0.04-0.71) and stage IIIB-IV (HR 0.16; 95% CI, 0.05-0.51). Further clinical studies are needed to improve the prognosis of patients with stage II-IV EMPD.

A single-center retrospective analysis of prognoses in patients with melanoma brain metastases and effectiveness of treatment in Japan.

BACKGROUND: Melanoma brain metastasis (MBM) has a poor prognosis, although recent treatments, including immune checkpoint inhibitors and targeted therapy, have improved the prognosis. However, these systemic therapies have been reported to be less efficient for Asian patients. We investigated the survival of Asian patients with MBM and the effectiveness of systemic therapies. METHODS: We retrospectively reviewed the survival rates of patients diagnosed with MBM between January 2011 and December 2021 at the National Cancer Center Hospital in Tokyo, Japan. In addition, we identified factors associated with survival using Cox regression analysis. RESULTS: A total of 135 patients were included. The median overall survival (OS) after an MBM diagnosis was 7.8 months (95% confidence interval [CI] 6.1-9.6). The 6-month and 1-year survival rates were 60.7% and 34.8%, respectively. We identified the prognostic factors of MBM, including non-acral primary location, low serum LDH levels, systemic therapy of single-agent immune checkpoint inhibitors (ICIs) or targeted therapies (TTs), and radiotherapy of stereotactic irradiation (STI). We found no significant difference in effectiveness between single-agent ICIs, the combination of Nivolumab and Ipilimumab (COMBI-ICI), and TTs (COMBI-ICI vs. single-agent ICI, hazard ratio 0.71, 95% confidence interval 0.27-1.88, p = 0.49; COMBI-ICI vs. TT: hazard ratio 0.46, 95% confidence interval 0.14-1.55, p = 0.21). CONCLUSIONS: Systemic therapy and radiotherapy have improved the survival of MBM patients, but the survival of Asian patients remains poor. Our findings suggest that COMBI-ICIs are not significantly more effective than single-agent ICI or TT in treating MBM.

A retrospective study of sentinel lymph node biopsy for skin cancer in Japan: Comparison with breast cancer and evaluation of factors related to its use.

BACKGROUND: Sentinel lymph node biopsy (SLNB) underuse has been reported for skin cancers; however, actual performance rates have not been compared. The objective of this study was to investigate the SLNB performance rate in skin cancers covered by health insurance in Japan and compare it with that in breast cancer. METHODS: This was a retrospective study of the SLNB performance rate in SLNB-eligible patients with breast or skin cancer from 2018 to 2019, utilizing a database linked to the Hospital-Based Cancer Registry and Diagnosis Procedure Combination survey. Demographic and tumor characteristics were analyzed using logistic regression. RESULTS: A total of 71,652 patients were included in this study. SLNB was performed in 86.4% (57,904/67,036) of the patients with breast cancer, 44.7% (694/1552) with melanomas, 3.1% (89/2849) with squamous cell carcinomas (SCCs), and 13.5% (29/215) with Merkel cell carcinomas (MCCs). The performance rate of SLNB was significantly lower for skin cancers than for breast cancers (odds ratio [OR], 0.03; p < 0.001). In addition, the performance rates of SLNB were significantly lower for SCCs and MCCs than for melanomas (SCC: OR, 0.04; p < 0.001; MCC: OR, 0.19; p < 0.001). Factors associated with SLNB performance included age, sex, year of incidence, primary tumor site, T stage, and number of hospital beds. CONCLUSIONS: SLNB is underutilized for skin cancer. Further investigation is required to explore the reasons for its underutilization so that it may be implemented more universally.

Prognostic factors in cutaneous apocrine carcinoma: a single-institution retrospective study of 32 patients.

BACKGROUND: Cutaneous apocrine carcinoma (CAC) is a rare adnexal carcinoma. Limited data exists on the demographics and overall survival (OS) of patients with CAC; thus, there is no consensus on surgical management. This study aimed to examine demographic and survival data of patients with CAC to determine optimal surgical management. METHODS: A single-center retrospective cohort study was conducted at the National Cancer Center Hospital in Tokyo between 2005 and 2022. Patients with a histologically-confirmed CAC diagnosis were identified and data on patient demographics, OS, and lymph node (LN) status were gathered. RESULTS: Thirty-two patients were included (median age, 65.5 years; male-female ratio, 15:1). The most common involvement site was the axilla (87.5%). Of the nine patients in the clinical local stage, pathological LN metastases were found in five patients. Either pathological LN or distant metastases were present in 75% of the patients at initial diagnosis. The most common initial surgical treatments included wide local excision and complete LN dissection. Across cohorts, the median OS was 39 months. Patients with ≥ 4 LN metastases had reduced recurrence-free survival and OS compared to those with ≤ 3 LN metastases (p = 0.042, p = 0.041, respectively). The OS was not remarkably different between patients who did and did not receive postoperative radiation therapy. CONCLUSIONS: Since CAC has a high rate of LN metastasis-and the number of LN metastases is a significant prognostic factor-LN evaluation should be considered for patients with CAC as initial treatment. Nonetheless, ≥ 4 LN metastases can be a poor prognostic factor for CAC.

Systemic therapy for Asian patients with advanced BRAF V600-mutant melanoma in a real-world setting: A multi-center retrospective study in Japan (B-CHECK-RWD study).

BACKGROUND: Anti-PD-1-based immunotherapy is considered a preferred first-line treatment for advanced BRAF V600-mutant melanoma. However, a recent international multi-center study suggested that the efficacy of immunotherapy is poorer in Asian patients in the non-acral cutaneous subtype. We hypothesized that the optimal first-line treatment for Asian patients may be different. METHODS: We retrospectively collected data of Asian patients with advanced BRAF V600-mutant melanoma treated with first-line BRAF/MEK inhibitors (BRAF/MEKi), anti-PD-1 monotherapy (Anti-PD-1), and nivolumab plus ipilimumab (PD-1/CTLA-4) between 2016 and 2021 from 28 institutions in Japan. RESULTS: We identified 336 patients treated with BRAF/MEKi (n = 236), Anti-PD-1 (n = 64) and PD-1/CTLA-4 (n = 36). The median follow-up duration was 19.9 months for all patients and 28.6 months for the 184 pa tients who were alive at their last follow-up. For patients treated with BRAF/MEKi, anti-PD-1, PD-1/CTLA-4, the median ages at baseline were 62, 62, and 53 years (p = 0.03); objective response rates were 69%, 27%, and 28% (p < 0.001); median progression-free survival (PFS) was 14.7, 5.4, and 5.8 months (p = 0.003), and median overall survival (OS) was 34.6, 37.0 months, and not reached, respectively (p = 0.535). In multivariable analysis, hazard ratios (HRs) for PFS of Anti-PD-1 and PD-1/CTLA-4 compared with BRAF/MEKi were 2.30 (p < 0.001) and 1.38 (p = 0.147), and for OS, HRs were 1.37 (p = 0.111) and 0.56 (p = 0.075), respectively. In propensity-score matching, BRAF/MEKi showed a tendency for longer PFS and equivalent OS with PD-1/CTLA-4 (HRs for PD-1/CTLA-4 were 1.78 [p = 0.149]) and 1.03 [p = 0.953], respectively). For patients who received second-line treatment, BRAF/MEKi followed by PD-1/CTLA-4 showed poor survival outcomes. CONCLUSIONS: The superiority of PD-1/CTLA-4 over BRAF/MEKi appears modest in Asian patients. First-line BRAF/MEKi remains feasible, but it is difficult to salvage at progression. Ethnicity should be considered when selecting systemic therapies until personalized biomarkers are available in daily practice. Further studies are needed to establish the optimal treatment sequence for Asian patients.

Clinical outcomes of head and neck mucosal melanoma treated with surgery: a single-center study in Japan.

BACKGROUND: Head and neck mucosal melanomas are rare malignancies. Although the prognosis is poor owing to the high incidence of distant metastases, locoregional control remains important. It is difficult to obtain results in a large cohort because of its rarity. This study aimed to elucidate the survival outcomes of patients with head and neck mucosal melanoma treated with surgery in Japan. METHODS: Patients with head and neck mucosal melanoma who were surgically treated between 2007 and 2021 at the National Cancer Center Hospital were retrospectively analyzed. RESULTS: A total of 47 patients were included in this study. The 5-year overall survival, disease-specific survival, locoregional control and relapse-free survival rates were 42%, 50%, 79% and 13%, respectively. The disease-specific survival of the oral mucosal melanoma group was significantly better than that of the sinonasal mucosal melanoma group (5-year disease-specific survival rate: 70% versus 37%, respectively; P = 0.04). Multivariate analyses revealed that sinonasal mucosal melanoma were independently significant adverse prognostic factor, for overall survival and disease-specific survival. Patients with oral mucosal melanoma patients had a higher incidence of lymph node metastasis than those with sinonasal mucosal melanoma patients (P < 0.0001). CONCLUSION: This study demonstrated the survival outcomes of the largest cohort of patients with head and neck mucosal melanomas treated surgically at a single institution within the past 20 years in Japan. We found that survival outcomes and incidence of nodal metastases varied by site.

Merkel cell carcinoma: a review of clinical management with focus on Asian patients.

Merkel cell carcinoma is a highly aggressive skin cancer characterized by neuroendocrine differentiation. This review aimed to present updates on the knowledge and current trends of clinical management of Merkel cell carcinoma. Additionally, we focused on Asian reports of Merkel cell carcinoma because most skin cancers differ substantially between Caucasians and Asians, and researchers have reported differences in Merkel cell carcinoma in racial and ethnic groups. Owing to its rarity, there is limited evidence for the epidemiology, pathogenesis, diagnosis and Merkel cell carcinoma treatment. The development of a nationwide survey or cancer registry, the identification of Merkel cell polyomavirus and the use of immune checkpoint inhibitors allowed a better understanding of its characteristics and biology and have revolutionized the clinical management of patients with Merkel cell carcinoma. Its incidence has gradually increased worldwide; however, it depends on the geographic location, race and ethnicity. No randomized prospective studies have evaluated the significance of sentinel lymph node biopsy, complete lymph node dissection and adjuvant radiation therapy; however, most patients with localized Merkel cell carcinoma are treated surgically or with post-operative radiation. Patients with distant Merkel cell carcinoma are administered immune checkpoint inhibitors as the first-line therapy; however, there is no established second-line therapy for refractory Merkel cell carcinoma. Furthermore, it is necessary to validate the favorable results of clinical studies performed in Western countries in the patients in Asia.

Efficacy of chemotherapies for unresectable extramammary Paget disease: a single-centre retrospective study.

BACKGROUND: Extramammary Paget disease (EMPD) is a cutaneous neoplasm that can metastasize to the lymph nodes and distant organs, resulting in a poor prognosis. For unresectable distant metastases of EMPD, no consensus has been reached regarding optimal chemotherapy owing to a lack of data. OBJECTIVES: To evaluate the efficacy of three regimens: docetaxel (DTX) monotherapy; combination therapy with 5-fluorouracil, epirubicin, carboplatin, vincristine and mitomycin C (FECOM); and tegafur (S-1) monotherapy. METHODS: This single-centre retrospective study included 32 patients diagnosed with unresectable EMPD and treated with chemotherapy between 2002 and 2022 at the National Cancer Center Hospital in Japan. Patient characteristics, responses to treatment and survival data were evaluated for each of the first-line therapies. RESULTS: Among the 17 patients who received DTX monotherapy, the response rate (RR) and disease control rate (DCR) were 47% and 77%, respectively. The median progression-free survival (PFS) and overall survival (OS) were 12.3 months [95% confidence interval (CI) 6.1-26.6] and 19.2 months (95% CI 8.5-not reached), respectively. Among the 11 patients who received combination FECOM chemotherapy, the RR and DCR were 55% and 64%, respectively. The median PFS and OS were 6.8 months (95% CI 3.5-not reached) and 13.4 months (95% CI 8.6-21.3), respectively. Among the four patients who received S-1 monotherapy, the RR and DCR were 0% and 25%, respectively. The median PFS and OS were 5.4 months (95% CI 2.3-not reached) and 12.5 (95% CI 2.3-not reached) months, respectively. CONCLUSIONS: Further investigations with prospective analysis are required to confirm these findings.

Epidemiology of skin cancer based on Japan's National Cancer Registry 2016-2017.

Skin cancer is most frequently diagnosed in the White population. However, its subtypes and epidemiology in Japan are understudied. We aimed to elucidate skin cancer incidence in Japan based on the National Cancer Registry, a new nationwide integrated population-based registry. Data from patients diagnosed with skin cancer in 2016 and 2017 were extracted and classified by cancer subtypes. Data were analyzed using the World Health Organization and General Rules tumor classifications. Tumor incidence was calculated as the number of new cases divided by the corresponding total person-years. Overall, 67,867 patients with skin cancer were included. The percentage of each subtype was as follows: basal cell carcinoma, 37.2%; squamous cell carcinoma, 43.9% (18.3% of which, in situ); malignant melanoma, 7.2% (22.1% of which, in situ); extramammary Paget's disease, 3.1% (24.9% of which, in situ); adnexal carcinoma, 2.9%; dermatofibrosarcoma protuberans, 0.9%; Merkel cell carcinoma, 0.6%; angiosarcoma, 0.5%; and hematologic malignancies, 3.8%. The overall age-adjusted incidence of skin cancer was 27.89 for the Japanese population model and 9.28 for the World Health Organization (WHO) model. The incidences of basal cell carcinoma and squamous cell carcinoma were the highest (3.63 and 3.40 per 100,000 persons, respectively, in the WHO model) among skin cancers, whereas the incidences of angiosarcoma and Merkel cell carcinoma were the lowest (0.026 and 0.038 per 100,000 persons, respectively, in the WHO model). This is the first report to provide comprehensive information on the epidemiological status of skin cancers in Japan using population-based NCR data.

Updated analysis of nivolumab and ipilimumab combination therapy in Japanese patients with advanced melanoma.

The efficacy and safety of nivolumab and ipilimumab (N + I) combination therapy for Japanese patients with advanced unresectable melanoma was re-evaluated in clinical practice. One hundred Japanese patients with advanced melanoma were included. The overall response rate was 24%; complete response (CR), 6%; partial response, 18%. The response rates were 33.3% in the systemic therapy-naïve and 15.4% in the prior-treatment groups, and 16.1% for patients who were treated with first-line anti-programmed death 1 antibody monotherapy followed by second-line N + I therapy after progression of the disease. The response rate for cutaneous melanoma was 32.7%, and 47.8% in the naïve group. Response rates for non-acral, acral, and mucosal melanoma were 34.9%, 25%, and 16.7%, respectively. The median progression-free survival (PFS) for all patients was 3.25 months (6.5 and 2.5 months in the naïve and prior-treatment groups, respectively). Median overall survival (OS) was 14.5 months (25.25 and 7.5 months in the naïve and prior-treatment groups, respectively). There were no significant differences in PFS or OS for patients with non-acral, acral, or mucosal melanoma. The 3-year PFS and OS were both 100% in patients who achieved CR with combination therapy. Adverse events occurred in 89% and were grade three or higher in 56% of cases. Although direct comparisons cannot be made due to different patient backgrounds, N + I combination therapy in Japanese patients in clinical practice tended to be inferior when compared to global study and non-Asian patients in clinical practice. The highest response rate was in the cutaneous melanoma therapy-naïve group. The best tumor response was associated with survival outcome, and the PFS and OS were good in cases where CR was obtained. The proportion of grade three and four adverse events was as high as that in the global study.

Safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma: Real-world experience from post-marketing surveillance.

To establish real-world evidence about the safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma, we conducted a nationwide cohort study using data from post-marketing surveillance for bexarotene treatment. In total, 294 patients with cutaneous T-cell lymphoma were identified between June 2016 and June 2018. Of these, 267 patients were included as the safety analysis set. Of the 267 patients, 175 were included in the efficacy analysis set. Of these, 139 patients had mycosis fungoides, including 46 with early stage disease and 93 with advanced stage disease. Among the 139 patients with mycosis fungoides, the objective response rate was 46.8%. A significant difference in objective response rate was detected between patients who started with bexarotene at 300 mg/m2 (61.6%) and patients who started with bexarotene at less than 300 mg/m2 (22.6%, p < 0.001). Of the 139 patients with mycosis fungoides, 92 were treated with a combination of bexarotene plus photo(chemo)therapy. A significant difference in objective response rate was seen between bexarotene with a combination of photo(chemo)therapy (57.6%) and bexarotene without a combination of photo(chemo)therapy (25.5%, p < 0.001). Starting bexarotene at 300 mg/m2 and combination with photo(chemo)therapy were detected as independent factors influencing response. Common treatment-related adverse events included hypothyroidism (85.8%), hypertriglyceridemia (68.5%), hypercholesterolemia (43.8%), and neutropenia (21.3%). Hypertriglyceridemia, hypercholesterolemia, and neutropenia occurred more frequently in patients who started with bexarotene at 300 mg/m2 than patients who started with bexarotene at less than 300 mg/m2 (hypertriglyceridemia, 76.4% vs. 57.0%, p = 0.001; hypercholesterolemia, 49.0% vs. 36.4%, p = 0.045; neutropenia, 28.0% vs. 12.1%, p = 0.002; respectively). The present study indicates that starting bexarotene at 300 mg/m2 and combination of photo(chemo)therapy offer a promising efficacy for the treatment of patients with mycosis fungoides. Efficacy of low-dose bexarotene plus photo(chemo)therapy should be evaluated in future.