PDCD1 and melanoma: A 2016 study by Ahmed at al investigating clinical outcomes in patients with melanoma brain metastases treated with SRS and anti-PD1, anti-CTLA4, BRAF/MEK inhibitors, BRAF inhibitors, and conventional therapy found distant 1-year disease control rate of 20% and 8% for BRAF/MEK inhibitors and BRAF inhibitors, respectively, and significantly improved overall survival for patients treated with anti-PD1, anti-CTLA4 and BRAF/MEK inhibitors when compared to those treated with conventional chemotherapy (66).