Prognostic importance of a second invasive primary melanoma according to tumour stage

Concordance of somatic mutational profile in multiple primary melanomas

This study aimed to determine the frequency and concordance of BRAF and NRAS mutation in tumours arising in patients with multiple primary melanoma (MPM). Patients with MPM managed at one of three tertiary referral centres in Melbourne, Australia, from 2010 to 2015 were included. Incident and subsequent melanomas underwent mutation testing. Cohen's kappa (κ) coefficient assessed agreement between incident and subsequent primary melanomas for both BRAF and NRAS mutation status (mutant versus wild-type). Mutation testing of at least two primary tumours from 64 patients was conducted. There was poor agreement for both BRAF and NRAS mutation status between incident and subsequent melanomas (κ = 0.10, 95% CI -0.10 to 0.42; κ = 0.06, 95% CI -0.10 to 0.57, respectively). In view of the low concordance in BRAF mutation status between incident and subsequent melanomas, mutational analysis of metastatic tissue, rather than of a primary melanoma, in patients with MPM should be used to guide targeted therapy.

[What's new in oncodermatology?]

This 'What's new in oncodermatology?' addresses the developments in 2017 on the epidemiology and management of skin cancers. We observe a constant increase in carcinomas, risk factors for squamous cell carcinoma, especially in transplant recipients where skin cancer mortality is important. Among epidemiological developments in melanoma are increased mortality despite screening, occupational exposure to UV, second melanoma and higher risk after carcinoma. New classifications that should be considered are AJCC8 for melanoma and carcinoma. In a near future artificial intelligence could change skin cancer screening practices through deep learning. For the sentinel lymph node, there is no interest in systematic lymphadenectomy that does not improve survival. Radiation therapy is essential for the prognosis of Merkel's carcinoma, and Mohs' surgery can be of interest. In metastatic melanoma, results on immunotherapy and targeted treatments include duration, dose, combinations, and the study of resistance mechanisms. The great novelty is immunotherapy or targeted therapy as an adjuvant treatment, giving an improvement in survival without relapse.