The prognostic value of programmed death-ligand 1 (PD-L1) and BRAF expression in nasopharyngeal carcinoma (NPC) is not well-defined. In this study the investigators investigated alterations in PD-L1, BRAF and EGFR by using immunohistochemistry analysis in a cohort of consecutively enrolled NPC patients.

NPC is a common type cancer in Macau and Southern China. The role of PD-L1 in NPC remains controversial. There many reasons behind these inconsistent findings. We used the SP263 antibody with the standard cut off value of 1% and 5%, which is frequently used for lung cancer and other cancer types. We also plan to include over 150 patients, which will be the largest study in NPC. This will help us to gain insights in NPC.

Inclusion Criteria:

• Above 18 years of age
• Locally advanced (stage IIIB) or metastatic (stage IV) NPC
• Fresh-frozen tissue samples were available were included
• After treatment with curative surgery or radiotherapy in Macau
• With follow up data were available

Exclusion Criteria:

• Enrolment in studies that prohibit any participation in this observational study

Consecutive patients who were pathologically diagnosed with NPC between 2006 and December 2010 at the Kiang Wu Hospital (Macau, SAR China) and for whom fresh-frozen tissue samples were available were included.