We evaluated the efficacy of nivolumab in patients with metastatic uveal melanoma previously untreated with ipilimumab. We performed a retrospective study at the National Cancer Center Hospital in Tokyo, Japan, where nivolumab was approved 1 year earlier than ipilimumab. Clinical efficacy outcomes were determined by assessing best overall response according to the Response Evaluation Criteria in Solid Tumors (version 1.1), progression-free survival and overall survival. Fourteen patients were analyzed; none had received any prior systemic therapies although eight had undergone transarterial chemoembolization. The median follow-up period was 15 months. The objective response and disease control rates were 7.1% and 42.9%, respectively (one partial response and five stable diseases). The median progression-free survival and overall survival were 10 (range, 4–105) and 60 (range, 5–105) weeks, respectively. Liver metastases in three patients were all programmed cell death-1 ligand negative. Lower lactate dehydrogenase, development of vitiligo, and a neutrophil-to-lymphocyte ratio less than 5 at week 6 were associated with favorable progression-free survival and overall survival; of these, only a neutrophil-to-lymphocyte ratio less than 5 at week 6 was statistically significant. Even with the use of nivolumab before ipilimumab, metastatic uveal melanoma appears to remain refractory to nivolumab monotherapy. However, because one patient in our cohort achieved an objective response, and the median overall survival exceeded 1 year, treatment strategies that incorporate anti-PD1 antibody should be further investigated. Whether a neutrophil-to-lymphocyte ratio less than 5 at week 6 is a favorable early on-treatment marker should be validated in larger cohorts.

The efficacy and safety of nivolumab + ipilimumab combination therapy were retrospectively examined in Japanese patients with unresectable advanced melanoma in clinical practice. Fifty‐seven patients with advanced melanoma received the nivolumab + ipilimumab combination therapy. The primary site was cutaneous, mucosal, uveal and unknown in 35, 16, two and four patients, respectively. The overall response rate was 26.3%, with complete response observed in two (3.5%) patients, partial response in 13 (22.8%), stable disease in 12 (21.1%) and progressive disease in 30 (52.6%). The response rate in the treatment‐naive and prior systemic therapy group was 40.7% and 13.3%, respectively. For those treated with a single immune checkpoint inhibitor followed by the nivolumab + ipilimumab combination therapy as second‐line therapy after disease progression, the response rate was 18.8%. Median progression‐free survival (PFS) and overall survival (OS) in all patients was 3.3 and 14 months, respectively. Median PFS in the treatment‐naive and prior systemic therapy groups was 13 and 2 months, respectively. Median OS was unreached in the treatment‐naive group and was 6.3 months in prior systemic therapy groups. There was no significant difference in PFS and OS for non‐acral, acral and mucosal melanoma. Adverse events occurred in 86% of patients; 56.1% were grade 3 or worse. The response rate in an actual clinical setting, including the prior systemic therapy group, was lower than that in the global study and the Japanese phase II study. However, in the treatment‐naive group, the rate was equivalent to that in the Japanese phase II study. PFS and OS in the treatment‐naive group were comparable with those in the global study and Japanese phase II study, suggesting that the treatment was effective. The proportion of grade 3 and 4 immune‐related adverse events was as high as that in the global study and Japanese phase II study.

Combination therapy with nivolumab + ipilimumab was recently approved for treating unresectable cases of malignant melanoma. In spite of the high response rate, it is associated with a high incidence of serious adverse events, including immune‐related hemophagocytic syndrome/hemophagocytic lymphohistiocytosis (irHPS/HLH), a difficult to diagnose rare disease. This is the first report of this disease in an Asian malignant melanoma patient treated with nivolumab + ipilimumab. A 69‐year‐old Japanese woman with unresectable malignant melanoma was treated with nivolumab + ipilimumab. Following the combined therapy, her fever and symptoms of malaise occurred, and she visited to our hospital's emergency department. Blood tests revealed significant liver dysfunction, anemia, and thrombocytopenia. We suspected irHPS/HLH, based on tests revealing decreased fibrinogen and significantly increased ferritin. Bone marrow biopsy revealed numerous macrophages and high hemophagocytosis levels. After 50 mg prednisolone (1 mg/kg per day) was administered, fever and cytopenia markedly improved. irHPS/HLH has a high rate of coagulation abnormalities accompanied by hypertriglyceridemia and hypofibrinogenemia, which are unlikely to occur in adult HPS/HLHs. Because irHPS/HLH responds better to steroids than other secondary HPS/HLHs, we expect a complete cure with steroids. Quick diagnosis and appropriate treatment based on clinical symptoms and laboratory tests are needed in suspected cases.

Treatment for patients with unresectable melanoma has been dramatically changed by the use of immunocheckpoint inhibitors (ICI). In this study, we reviewed patients with unresectable stage III/IV melanoma, who were treated with nivolumab between and retrospectively recorded cutaneous adverse events (cAE), development of vitiligo, clinical characteristics and clinical responses. We identified 128 patients, 61 (47.7%) of whom showed cAE, including 30 (23.4%) with development or exacerbation of vitiligo. The prognosis of patients with melanoma treated with ICI correlated with cAE, including development of vitiligo. Patients with cAE showed better objective responses (41.0% vs 6.0%, P < 0.001), progression-free survival (PFS) (377 vs 61 days, P < 0.001) and overall survival (OS) (763 vs 209 days, P < 0.001) than did patients without cAE. Patients who developed vitiligo showed better objective responses (53.3% vs 29.0% vs 6.0%, P < 0.001), PFS (median, not reached vs 317 vs 65 days, P < 0.001) and OS (not reached vs 689 vs 209 days, P < 0.001) than did patients with other cAE and patients without cAE. Landmark analysis showed development of vitiligo starting 20 weeks after starting nivolumab correlated with better OS. In multivariate analysis, OS correlated with performance status, number of metastasized organs, cAE other than vitiligo and development of vitiligo. Despite the fact that the correlation between other cAE and OS was less than that of vitiligo, cAE may be a simple marker of favorable prognosis.

Extramammary Paget's disease (EMPD) often invades the dermis and metastasizes to the lymph nodes. Patients with EMPD associated with lymph node metastases have poor prognosis; to date, effective treatment has not yet been established. Lymph node dissection, aiming to control the local disease, is a standard form of management for EMPD patients with lymph node metastases (LNM). We investigated the clinical and pathological features, treatment strategies and prognostic factors of patients with metastatic EMPD who underwent lymph node dissection. We retrospectively evaluated 38 cases of extramammary Paget's disease with lymph node metastasis over 10 years. All patients underwent wide resection of the primary lesion and lymph node dissection. Univariate analysis revealed the number of metastatic nodes and lymphadenopathy as prognostic factors. In multivariate analysis, the number of metastatic lymph nodes retained statistical significance (hazard ratio, 35.3; 95% confidence interval, 3.23-387.0; P = 0.003). The 5-year survival rate was 100% and 19.1% in patients with two or less LNM and with three or more LNM, respectively. In patients with three or more LNM, the 5-year survival rate after adjuvant radiation therapy was better than that after surgery alone (75% vs 0%). In conclusion, patients with two or less LNM can be expected to have long-term survival with lymph node dissection only, while patients with three or more LNM may require adjuvant radiation therapy to improve prognosis. These results suggest that lymph node dissection may be a strategy to treat EMPD with regional LNM. METHODS PatientsThis retrospective analysis examined a prospectively maintained database of 89 EMPD patients with dermal invasion who were treated at