Unusual Clinical Experience in BRAF Exon 15 p.K601E-Mutated Lung Cancer: A Case Report and Brief Review of the Literature

Molecular profiling has revolutionized the treatment of metastatic NSCLC. Uncommon mutations have been reported primarily in EGFR and BRAF genes and are frequently associated with atypical clinical presentations. Here, we present a rare case of a patient affected by BRAF exon 15 p.K601E-mutated lung cancer with synchronous peritoneal carcinomatosis. First line treatment with chemo-immunotherapy combinations provided a PFS of 8–9 months, whereas a second line treatment with BRAF and MEK inhibitors elicited a dissociated response. The latter clinical outcome suggests that these inhibitors have only partial activity against this rare mutation.