Anlotinib Plus Sintilimab as First-line Treatment for Advanced Non Clear Cell Renal Cell Carcinoma

Inclusion Criteria: * Subjects voluntarily joined the study and signed informed consent; * Aged \> 18 years; * ECOG body status score is 0 or 1,Expected survival time is greater than 3 months. * Locally advanced or metastatic, histological confirmed, non-clear cell RCC of all subtypes. Patients must have advanced non-clear cell of one of the following subtypes: papillary, chromophobe, collecting duct carcinoma (CDC), renal medullary carcinoma (RMC), or unclassified. * Patients must have measurable lesions as defined by the RECIST 1.1 standard; * Adequate hematologic and end-organ function as defined by the following laboratory results obtained within 28 days prior to the first study treatment: 1. Absolute neutrophil count (ANC) ≥1.5x 109/L 2. Lymphocyte count ≥ 500/uL. 3. Platelet count ≥ 80x109/L. 4. Hemoglobin ≥ 80 g/L (patients may be transfused to meet this criterion). 5. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 x upper limit of normal (ULN) with the following exceptions: Patients with documented liver/bone metastases should have AST and ALT ≤ 5 x ULN. 6. Serum bilirubin ≤ 1.5 x ULN. 7. Creatinine clearance ≥ 60 mL/min. 8. For female patients of childbearing potential and male patients with partners of childbearing potential, agreement (by patient and/or partner) to use highly effective forms of contraception and to continue its use 4 weeks after the last dose of anlotinib or sintilimab. * Signed informed consent form. * Ability and capacity to comply with study and follow-up procedures. Exclusion Criteria: * Those who are known to be allergic to pharmaceutical ingredients. * Receive anti-tumor monoclonal antibody or other research drugs within 4 weeks before enrollment; have received other anti-PD-1 antibody therapy or other treatment for PD-1/PD-L1; * Previous use of anlotinib or other angiogenesis inhibitors * The patient has any active autoimmune disease or a history of autoimmune disease; * There are uncontrolled heart clinical symptoms or diseases; * Patients with congenital or acquired immune deficiency; * Receive chemotherapy, targeted therapy, radiotherapy within 2 weeks before enrollment; * A history of gastrointestinal perforation or major surgery within 4 weeks before enrollment; * Overactive/venous thrombosis occurred within 6 months prior to enrollment, such as cardiovascular-cerebral vascular (including transient ischemic attack),deep vein thrombosis (except for patients who have recovered from venous catheterization due to previous chemotherapy)and pulmonary embolism; * Those with active bleeding or bleeding tendency; * Presence of a drug uncontrolled hypertension; * Urine routine indicates more than urinary protein 2+; * Correct QT interval \> 470msec; if the patient has a prolonged QT interval, but the investigator's study evaluates that the prolongation is due to a cardiac pacemaker (and no other abnormalities in the heart), it is necessary to discuss with the sponsor's researcher to determine if the patient is Suitable for group study; * Patients suspected of having other primary cancers; * Those who are known to be allergic to pharmaceutical ingredients. * Patients with active or chronic hepatitis B (defined as having a positive hepatitis B surface antigen \[HBsAg\] test at screening). Patients with past/resolved HBV infection (defined as having negative HBsAg test and a positive antibody to hepatitis B core antigen \[anti-HBc\] antibody test) are eligible. A negative HBA DNA test must be obtained in patients with positive hepatitis B core antibody prior to Cycle 1 Day 1. * Active hepatitis C infection. Patients positive hepatitis C antibody test are eligible if PCR is negative for hepatitis C viral DNA. * Pregnant or lactating women.