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Summary: Background: Acral melanoma (AM) is the most common histopathological subtype of malignant melanoma in Asians. However, differences in the mutational profiles underlying AM and nonacral cutaneous melanoma (NAM) in Asians are not well understood. Objectives: To augment the understanding of the prevalence, patterns and associations of various mutations between different subtypes of melanoma. Methods: We performed comprehensive genomic profiling of 409 cancer‐associated genes, using next‐generation sequencing, in 66 primary melanomas comprised of 45 AMs and 21 NAMs. Results: Most of the AMs (n = 27/45; 60%), but only five of 21 (24%) NAMs, were triple wild‐type (triple‐WT) tumours. Compared with AMs, NAMs exhibited a significantly higher frequency of BRAF mutations. The frequencies of NRAS/KRAS mutations, cell‐cycle aberrations, copy number gains in BIRC2,BIRC3 and BIRC5, and gains of receptor tyrosine kinase genes were significantly higher in AMs. Ulceration was found at significantly higher rates in the AMs and NAMs with cell‐cycle aberrations and gains of receptor tyrosine kinase genes. Notably, cell‐cycle aberrations and copy number gains in BIRC2,BIRC3 and BIRC5 were significantly associated with poor melanoma‐specific survival in the 66 patients with melanoma and especially in the 45 patients with AM. Multivariate analysis showed that lymph node metastasis and cell‐cycle aberrations were independent prognostic factors of melanoma‐specific survival. Conclusions: This study strengthens our understanding of the patterns and clinical associations of oncogenic mutations in AMs and NAMs in Asians. What's already known about this topic? Mutation frequencies of driver genes vary between melanoma subtypes.Acral melanoma is the most common subtype of melanoma in Asians.KIT mutations and copy number variations occur more frequently in the acral subtype of melanoma than in the nonacral subtype What does this study add? NRAS/KRAS mutations, cell‐cycle aberrations, copy number gains in BIRC2, BIRC3 and BIRC5, and amplifications of receptor tyrosine kinase genes were significantly enriched in acral melanoma and could be potential targets for treatment.Melanomas with cell‐cycle aberrations and gains in receptor tyrosine kinase genes were significantly more likely to contain ulceration. What is the translational message? Cell‐cycle aberrations and copy number gains in BIRC2, BIRC3 and BIRC5 were significantly associated with poor melanoma‐specific survival.These observations should be explored further for future drug development. Linked Comment: Johansson. Br J Dermatol 2020; 182:1085. Plain language summary available online [ABSTRACT FROM AUTHOR]

Summary: Melanoma is a life‐threatening type of skin cancer. It affected about 351,800 people worldwide in 2015. Acral melanoma occurs on non‐hairy acral skin (palms, soles, and nail beds) and is not thought to be linked to ultraviolet radiation (e.g. from the sun), unlike other melanoma types (non‐acral melanoma). This study, conducted by researchers based in Taiwan, aimed to find out which mutations (abnormalities) in certain genes underly acral melanoma and non‐acral melanoma in Asians. This is known as 'genomic profiling', and allows scientists to find out about the genetic information related to a person or cell type and the way genes interact with each other. This profiling can be done using a type of genetic testing called next‐generation sequencing. The authors performed comprehensive genomic profiling of 409 cancer‐associated genes in 66 melanomas, comprised of 45 acral melanomas and 21 non‐acral melanomas. The authors found that the non‐acral melanomas showed a significantly higher frequency of a type of mutation called BRAF mutations than the acral melanomas. Meanwhile, the frequencies of other alterations (NRAS/KRAS mutations, cell cycle aberrations, anti‐apoptosis pathway alterations, and receptor tyrosine kinase gene gains) were significantly higher in the acral melanomas. Ulceration, in which the skin on the surface of the melanoma breaks down, was found at significantly higher rates in the acral melanomas and non‐acral melanomas with cell cycle aberrations and receptor tyrosine kinase gene gains. Notably, cell cycle aberrations and anti‐apoptosis pathway alterations were associated with a lower rate of survival in all 66 melanoma patients, and especially in the 45 acral melanoma patients. This study strengthens our understanding of the patterns and repercussions of gene mutations in acral and non‐acral melanoma in Asians. The study revealed that, in addition to treatments called immunotherapies, acral melanoma patients might benefit from treatments that target NRAS/KRAS mutations, cell cycle aberrations, receptor tyrosine kinase gains, and anti‐apoptosis pathways, a possibility which warrants study in the future. This is a summary of the study: Genetic alterations in primary melanoma in Taiwan. Linked Article: Sheen et al. Br J Dermatol 2020; 182:1205–1213 [ABSTRACT FROM AUTHOR]

Carcinoma of the uterine cervix has been the leading malignant neoplasm treated in our department. A comparative study was carried out using conventional low dose rate (LDR) with 137Cs sources (less than or equal to 100 cGy/hr) versus high dose rate (HDR) with 60Co sources (greater than 100 cGy/min) in the intracavitary (IC) application following external pelvic irradiation. A total of 399 patients were treated with external RT plus HDR radiation treatment alone from February 1980 through December 1985. Stage IIb and IIIb comprised 79.4% of cases (317 cases). The rate of initial complete response of the tumor, local control, and survival rate seemingly were better in the HDR group, but there was no significant difference statistically. The actuarial survival rates in all cases/definitive RT cases are 85%/85% for Stage 0-IIa, 53%/70% for IIb, 43%/49% for IIIa, 43%/53% for IIIb, 42%/47% for IVa, respectively. Complications were similar and the rectal complications were slightly higher in HDR group. The combination of pelvic irradiation with HDR intracavitary irradiation was more convenient for patients and also for personnel. The HDR technique may be a good substitution for IC treatment.