The detection of V600E BRAF mutation in melanoma is fundamental since here BRAF inhibitors represent an effective treatment.,Non-V600E BRAF mutations that may also respond are not detected by certain screening methods.,Thus, knowledge about detection of these mutations is needed.,A total of 276 tumour samples from 174 melanoma patients were investigated for BRAF mutations by pyrosequencing.,Rare mutations were confirmed by capillary sequencing and compared with findings from COBAS test and immunohistochemistry using a novel BRAF antibody.,Melanoma type, localisation, and survival were summarised.,BRAF mutations were found in 43% of patients (124 tumours in 75 patients).,Among those, 14 patients (18.7%) exhibited rare mutations.,The V600EK601del and V600DK601del mutations have never been described before in melanoma.,Furthermore, V600K, V600E2, and V600D, V600G, V600R, and L597S mutations were detected.,Mutations were not detected by COBAS test in 7 out of these 14 patients and immunohistochemistry only reliably detected patients with the V600E2 and V600EK601del mutation.,Accurate diagnosis of rare BRAF mutations is crucial.,We show that pyrosequencing is accurate, highly sensitive, reliable, and time saving to detect rare BRAF mutations.,Missing these rare variant mutations would exclude a subset of patients from available effective BRAF-targeting therapy.
BRAF is a serine/threonine protein kinase activating the MAP kinase/ERK-signaling pathway.,About 50 % of melanomas harbors activating BRAF mutations (over 90 % V600E).,BRAFV600E has been implicated in different mechanisms underlying melanomagenesis, most of which due to the deregulated activation of the downstream MEK/ERK effectors.,The first selective inhibitor of mutant BRAF, vemurafenib, after highly encouraging results of the phase I and II trial, was compared to dacarbazine in a phase III trial in treatment-naïve patients (BRIM-3).,The study results showed a relative reduction of 63 % in risk of death and 74 % in risk of tumor progression.,Considering all trials so far completed, median overall survival reached approximately 16 months for vemurafenib compared to less than 10 months for dacarbazine treatment.,Vemurafenib has been extensively tested on melanoma patients expressing the BRAFV600E mutated form; it has been demonstrated to be also effective in inhibiting melanomas carrying the V600K mutation.,In 2011, both FDA and EMA therefore approved vemurafenib for metastatic melanoma carrying BRAFV600 mutations.,Some findings suggest that continuation of vemurafenib treatment is potentially beneficial after local therapy in a subset of patients with disease progression (PD).,Among who continued vemurafenib >30 days after local therapy of PD lesion(s), a median overall survival was not reached, with a median follow-up of 15.5 months from initiation of BRAF inhibitor therapy.,For patients who did not continue treatment, median overall survival from the time of disease progression was 1.4 months.,A clinical phase I/II trial is evaluating the safety, tolerability and efficacy of vemurafenib in combination with the CTLA-4 inhibitor mAb ipilimumab.,In the BRIM-7 trial vemurafenib is tested in association with GDC-0973, a potent and highly selective inhibitor of MEK1/2.,Preliminary data seem to indicate that an additional inhibitor of mutated BRAF, GSK2118436, might be also active on a wider range of BRAF mutations (V600E-K-D-R); actually, treatment with such a compound is under evaluation in a phase III study among stage III-IV melanoma patients positive for BRAF mutations.,Overall, BRAF inhibitors were well tolerated; common adverse events are arthralgia, rash, fatigue, alopecia, keratoacanthoma or cutaneous squamous-cell carcinoma, photosensitivity, nausea, and diarrhea, with some variants between different inhibitors.