This is a multicenter retrospective study designed to compare overall survival (OS) by PD-L1 expression status in patients with RCC who have received systemic chemotherapy for recurrent or metastatic RCC, to determine whether the prognosis is worse in PD-L1-positive than in PD-L1-negative RCC.

Total 600 RCC surgical specimens will be collected from patients who started systemic chemotherapy for recurrent or metastatic RCC between January 1, 2010 and December 31, 2015 at about 30 participating study sites in Japan.

PD-L1 expression status (IC; immune cell) on tumor-infiltrating immune cells will be evaluated by IHC, and classified by score: IC0 (PD-L1-negative) and IC1, IC2, IC3 (PD-L1-positive). Unless otherwise specified, between-group comparisons will be performed between IC0 and IC1/2/3.

Inclusion Criteria:

• 1. Written informed consent for this study. In the case obtaining written informed consent is difficult due to death, change of address, and so on, the opt-out consent is accepted by giving patients or their relatives notification regarding the usage of their clinical information and surgical samples for the research.
• 2. Age at nephrectomy≧20 years
• 3.Patients with recurrent or metastatic RCC who have initiated first line treatment between 1 January 2010 and 31 December 2015, with representative FFPE of nephrectomy surgical specimen which are suitable for assessment of PD-L1 expression

Exclusion Criteria:

• 1. Malignancies other than RCC is co-existed from the time of nephrectomy and death.
• 2. Treatment with anti-CTLA-4 antibody, anti-PD-1/PD-L1 antibodies as first-line therapy for recurrent or metastatic RCC.

Patients with recurrent or metastatic RCC who have initiated first line treatment between 1 January 2010 and 31 December 2015, with representative FFPE of nephrectomy surgical specimen which are suitable for assessment of PD-L1 expression

Qualified researchers may request access to individual patient level data through the clinical study data request platform (ClinicalStudyDataRequest.com). For further details on Chugai's Data Sharing Policy and how to request access to related clinical study documents, see here (www.chugai-pharm.co.jp/english/profile/rd/ctds\_request.html)