Eligibility Criteria:
Inclusion Criteria:
* Patients voluntarily participated in this study and signed informed consent;
* Patients ≥18 years old;
* ECOG score ≤2 points; Expected survival ≥6 months;
* Pathological diagnosis of adrenal cortical carcinoma;
* Inability or unwillingness to surgically resect recurrent or metastatic adrenal cortical cancer;
* Adrenal cortical cancer has recurred or metastasized after receiving mitotan monotherapy, chemotherapy, or first-line regimens based on mitotan combined with cisplatin chemotherapy and has progressed, unable to tolerate or unwilling to accept the regimens;
* Have at least one measurable lesion (RECIST1.1);
* The main organs function well, and the laboratory examination indicators meet:
* (1) Blood routine examination: Hemoglobin (HB) ≥90g/L(5.6mmol/L); Absolute neutrophil count (ANC) ≥1.5×109/L; Total white blood cells ≥3.5×109/L;
* Platelet (PLT) ≥80×109/L; (2) Blood biochemical examination:
① Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2.5×ULN (liver metastasis/bone metastasis ≤5× ULN; Tumor bone metastasis ≤5ULN);
② Serum total bilirubin (TBIL) ≤1.5×ULN;
* Serum creatinine Cr≤1.5×ULN or creatinine clearance ≥60ml/min; Blood urea nitrogen (BUN)≤2.5× upper limit of normal value (ULN); ④ Albumin (ALB)≥30g/L; (3) Blood coagulation test: Activated partial thromboplastin time (APTT), International Normalized ratio (INR), prothrombin time (PT) ≤1.5×ULN;
* Women of childbearing age must confirm their non-pregnant status before enrollment, and all enrolled subjects (whether male or female) should take adequate contraceptive measures during the whole treatment period and 4 weeks after the end of treatment;
* The subjects were willing to return to the hospital for follow-up and had good compliance.
Exclusion Criteria:
* Receiving anti-tumor monoclonal antibodies or other investigational drugs before enrollment
* Previously received other anti-PD-1 monoclonal antibody therapy or other drug therapy for PD-1 / PD-L1
* Radiotherapy has been used in the lesion area in the past
* The lesion invades the intestinal duct, and there are contraindications to radiotherapy such as the risk of intestinal fistula caused by radiotherapy
* Known allergic reaction to the active ingredient of PD-1 monoclonal antibody or any excipients
* Have a medical condition that interferes with oral medication, including but not limited to difficulty swallowing, chronic diarrhea, or intestinal obstruction
* Uncontrolled heart disease, such as heart failure with NYHA rating ≥2, unstable angina pectoris, history of myocardial infarction in the past year, and ventricular or supraventricular arrhythmias requiring treatment
* Central nervous system metastasis with clinical symptoms, such as brain edema, requiring hormonal intervention, or brain metastasis progression;
* Serious infections (CTCAE \> Grade 2) occurred within 4 weeks prior to the first use of the study drug, such as severe pneumonia, bacteremia, and infection complications requiring hospitalization; Baseline chest imaging examination indicating active lung inflammation, signs and symptoms of infection within 2 weeks prior to first use of the study drug, or the need for oral or intravenous antibiotic treatment (excluding prophylactic antibiotic use)
* Receive systemic sex hormone or other immunosuppressive therapy with an equivalent dose greater than 10mg prednisone/day within 4 weeks of signing the informed consent. Participants with a systemic sex hormone dose ≤10mg prednisone/day or inhaled/topical corticosteroids could be enrolled
* chronic hepatitis B active stage or active hepatitis C patients. Screening period hepatitis B surface antigen (HepatitsBSurfaceAntigen, HBsAg) or hepatitis b core antibody (HBcAb HepatitsBcoreAntibody,) or hepatitis c virus (HepatitisCVirus, HCV) antibody positive patients, Only through HepatitisBVirus (HBV) DNA detection (no more than 104 copies /mL or 2000IU/mL) and HCVRNA detection (no more than the lower limit of the assay) will he be included in the group test after the disease has been controlled. Hepatitis B virus carriers, hepatitis B whose disease has been controlled after drug treatment (no more than 104 copies /mL of DNA or 2000IU/mL), and cured hepatitis C patients can be enrolled
* Significant vital organ dysfunction or uncontrollable comorbiditions, including but not limited to uncontrolled hypertension, decompensated cirrhosis, active peptic ulcer or bleeding disease
* History of interstitial lung disease or non-infectious pneumonia; Participants with a history of drug-induced or radiation-induced non-infectious pneumonia without symptoms were admitted
* Pregnant and lactating women and subjects of childbearing age who do not want to take contraceptive measures
* Persons with mental illness, a history of alcohol or drug abuse, or inability to obtain informed consent
* Other researchers have determined that participants are not suitable for this study, such as serious diseases, including mental illness, serious abnormal test results, and other social or family high-risk risk factors that require timely intervention
* refuse or can not sign the informed consent.
* Patients suspected of having other primary cancers; Patients with other primary malignancies within the 5 years prior to the study period (other than adequately treated cervical or skin cancer in situ, such as basal cell carcinoma, squamous cell carcinoma, or non-melanoma skin cancer)