Cystadenocarcinoma of the parotid: case report of a BRAF inhibitor treatment

BACKGROUND: Mutations of the proto-oncogene BRAF have been described in many cancers. Mutated BRAF causes overactive downstream signaling via MEK and ERK leading to excessive cell proliferation and survival. Their identification is of real interest because specific inhibitors have been developed. METHODS AND RESULTS: We report the case of a patient with an aggressive cystadenocarcinoma of the parotid with synchronous metastases. Cisplatine/5FU chemotherapy associated with palliative radiation therapy was used first without any efficency nor clinical improvement. A molecular analysis revealed a BRAF mutation. A compassionate treatment with a BRAF inhibitor showed very good results from the first month. The patient reported real improvement in clinical condition and pain. From an imaging point of view, computed tomographies reported a complete response on mediastinal lymph nodes and regeneration on bone metastases. CONCLUSION: This first report suggests BRAF could be a potent oncogenic driver in salivary gland carcinoma. It deserves a multicenter academic prospective trial to provide proof of efficiency with BRAF inhibitors in theses tumors.