Tumour mutation status and sites of metastasis in patients with cutaneous melanoma

• Published in: British journal of cancer 2017-09, Vol.117 (7), p.1026-1035
• Main Authors: Adler, Nikki R, Wolfe, Rory, Kelly, John W, Haydon, Andrew, McArthur, Grant A, McLean, Catriona A, Mar, Victoria J
• Format: Article
• Language: English
• Subjects: 631/67/1813/1634; 631/67/322; Adult; Aged; Aged, 80 and over; Biomedical and Life Sciences; Biomedicine; Biopsy; Cancer Research; Central nervous system; Central Nervous System Neoplasms - genetics; Central Nervous System Neoplasms - secondary; Drug Resistance; Epidemiology; Female; GTP Phosphohydrolases - genetics; Health risk assessment; Humans; Liver; Liver Neoplasms - genetics; Liver Neoplasms - secondary; Lung Neoplasms - genetics; Lung Neoplasms - secondary; Lungs; Lymph; Lymph nodes; Lymphatic Metastasis - genetics; Lymphatic system; Male; Melanoma; Melanoma - genetics; Melanoma - secondary; Membrane Proteins - genetics; Metastases; Metastasis; Middle Aged; Molecular Diagnostics; Molecular Medicine; Mutation; Neoplastic Cells, Circulating; Oncology; Prospective Studies; Proto-Oncogene Proteins B-raf - genetics; Regional development; Sentinel Lymph Node - pathology; Skin Neoplasms - genetics; Skin Neoplasms - pathology; Survival Rate; Tumors; Young Adult
• ISSN: 0007-0920; 1532-1827
• DOI: 10.1038/bjc.2017.254

Background: Cutaneous melanoma can metastasise haematogenously and/or lymphogenously to form satellite/in-transit, lymph node or distant metastasis. This study aimed to determine if BRAF and NRAS mutant and wild-type tumours differ in their site of first tumour metastasis and anatomical metastatic pathway. Methods: Prospective cohort of patients with a histologically confirmed primary cutaneous melanoma at three tertiary referral centres in Melbourne, Australia from 2010 to 2015. Multinomial regression determined clinical, histological and mutational factors associated with the site of first metastasis and metastatic pathway. Results: Of 1048 patients, 306 (29%) developed metastasis over a median 4.7 year follow-up period. 73 (24%), 192 (63%) and 41 (13%) developed distant, regional lymph node and satellite/in-transit metastasis as the first site of metastasis, respectively. BRAF mutation was associated with lymph node metastasis (adjusted RRR 2.46 95% CI 1.07–5.69, P =0.04) and sentinel lymph node positivity (adjusted odds ratio [aOR] OR 1.55, 95% CI 1.14–2.10, P =0.005). BRAF mutation and NRAS mutation were associated with increased odds of developing liver metastasis (aOR 3.09, 95% CI 1.49–6.42, P =0.003; aOR 3.17, 95% CI 1.32–7.58, P =0.01) and central nervous system (CNS) metastasis (aOR 4.65, 95% CI 2.23–9.69, P