Clinical and histopathological characteristics and survival analysis of 4594 Japanese patients with melanoma

Abstract

Background The incidence of melanoma among those of an Asian ethnicity is lower than in Caucasians; few large‐scale Asian studies that include follow‐up data have been reported. Objectives To investigate the clinical characteristics of Japanese patients with melanoma and to evaluate the prognostic factors. Methods Detailed patient information was collected from the database of Japanese Melanoma Study Group of the Japanese Skin Cancer Society. The American Joint Committee on Cancer seventh Edition system was used for TNM classification. The Kaplan‐Meier method and Cox proportional hazards model were used to estimate the impact of clinical and histological parameters on disease‐specific survival in patients with invasive melanoma. Results In total, 4594 patients were included in this analysis. The most common clinical type was acral lentiginous melanoma (40.4%) followed by superficial spreading melanoma (20.5%), nodular melanoma (10.0%), mucosal melanoma (9.5%), and lentigo maligna melanoma (8.1%). The 5‐year disease‐specific survival for each stage was as follows: IA = 98.0%, IB = 93.9%, IIA = 94.8%, IIB = 82.4%, IIC = 71.8%, IIIA = 75.0%, IIIB = 61.3%, IIIC = 41.7%, and IV = 17.7%. Although multivariate analysis showed that clinical classifications were not associated with survival across all stages, acral type was an independent poor prognostic factor in stage IIIA. Conclusions Our study revealed the characteristics of melanoma in the Japanese population. The 5‐year disease‐specific survival of each stage showed a similar trend to that of Caucasians. While clinical classification was not associated with survival in any stages, acral type was associated with poor survival in stage IIIA. Our result might indicate the aggressiveness of acral type in certain populations.

Genetic alterations in primary melanoma in Taiwan

“…In this study, the incidence of cytoband gains was significantly higher in AMs than in NAMs. This result may partially explain the generally poorer prognosis for AM …”

“…This helps to explain why most patients with AMs would not benefit from BRAF inhibitors (Table S10). Besides, compared with NAMs, lower mutation burdens are found in AMs, which have previously demonstrated a lower response rate to checkpoint inhibitors . The co‐occurrence of several structural variants may change the cancer cell phenotype, making it more resistant to therapy .…”

Usefulness of neuron‐specific enolase as a serum marker of metastatic melanoma

“…Four of the present five stage IV patients showing elevated sNSE but not sLDH had mucosal‐type melanomas. The mucosal type was reported in 10% of Japanese melanoma patients, 19 but clinical trials and real‐world data in Japan have shown that the mucosal type accounts for 25–40% of the melanoma patients who required systemic therapy in the advanced stage 20,21 . Because of the limited number of cases, it is necessary to examine greater numbers of melanoma patients to determine the precise usefulness of sNSE as a biomarker of mucosal melanoma and its potential superiority to sLDH.…”

Treatment of Advanced Melanoma: Past, Present and Future

“…The ORR of nivolumab monotherapy in a Japanese population was again much lower than that in a Caucasian population according to post-marketing surveillance analysis in Japan (22.2%) [51]. Notably, the most common subtype of melanoma in Japan was acral lentiginous melanoma (ALM) (40.4%) [52], while the ratio of ALM in a non-Hispanic, white-skinned population in the United States was much lower (1%) [53]. A previous report also suggested that the ORR of anti-PD1 Abs for ALM and mucosal melanoma was lower in a Caucasian population [54].…”