• Progression-free survival [ Time Frame: 2 years ]
  Progression-free survival (PFS) will be defined as the elapsed time from the first date of study treatment until documented disease progression (as per mRECIST) or death from any cause, whichever is earlier. For patients who remain alive without progression, follow-up time will be censored at the date of last disease assessment.
• Adverse event rate [ Time Frame: 2 years ]
  Adverse event rate will be defined as the rate of patients who developed adverse event.

Head/Neck cancer is a kind of hard-to-treat malignancy worldwide and its overall survival rate is still low. PD1/PDL1 inhibitor are widely used to treat various of cancers in China now. The neck arterial chemotherapy infusion for advanced HNC, through the "first pass effect" of drug treatment, can significantly increase the local drug concentration of the tumor, improve the efficacy, and reduce systemic adverse reactions.

To the investigator's knowledge, no studies have been developed on the survival benefit of neck artery infusion of immunotherapeutic agents in patients with advanced HNC. This phase III clinical trial was designed to compare the effects of PD1/PDL1 inhibitor via IA and IV on the survival benefit of patients with advanced HNC, including ORR, DCR, median survival time, and safety.

• Experimental: PD1/PDL1 inhibitor infusion via neck artery
  Interventional technique is used to localize neck artery to infuse the inhibitors directly into tumor.
  Intervention: Drug: PD1/PDL1 inhibitor
• Experimental: PD1/PDL1 inhibitor infusion via peripheral vein
  Routine peripheral vein infusion of PD1/PDL1 inhibitor is performed as control.
  Intervention: Drug: PD1/PDL1 inhibitor

Inclusion Criteria:

1. Cytohistological confirmation is required for diagnosis of HNC.
2. Signed informed consent before recruiting.
3. Age between 18 to 80 years with estimated survival over 3 months.
4. ECOG score < 2
5. Tolerable coagulation function or reversible coagulation disorders
6. Laboratory examination test within 7 days prior to procedure: WBC≥3.0×10E9/L; Hb≥90g/L； PLT ≥50×10E9/L；INR < 2.3 or PT < 6 seconds above control；Cr ≤ 145.5 umul/L；Albumin > 28 g/L；Total bilirubin < 51 μmol/L
7. At least one tumor lesion meeting measurable disease criteria as determined by RECIST v1.1.
8. Patients with advanced HNC which would not be suitable for treatment with loco-regional therapies or have progressed following locoregional therapy such as surgical resection and other treatment.
9. Birth control.
10. Willing and able to comply with scheduled visits, treatment plan and laboratory tests.

Exclusion Criteria:

1. Patients participated in other clinical trials of equipment or drugs (signed informed consent) within 4 weeks;
2. Any serious accompanying disease, which is expected to have an unknown, impact on the prognosis, include heart disease, inadequately controlled diabetes and psychiatric disorders;
3. Patients accompanied with other tumors or past medical history of malignancy;
4. Pregnant or lactating patients, all patients participating in this trial must adopt appropriate birth control measures during treatment;

5. Patients have poor compliance.

   Any contraindications for neck artery infusion procedure:

   A. Impaired clotting test (platelet count < 60000/mm3, prothrombin activity < 50%).

   B. Renal failure / insufficiency requiring hemo-or peritoneal dialysis. C. Known severe atheromatosis. D. Known uncontrolled blood hypertension (> 160/100 mm/Hg).

6. Allergic to adriamycin chemotherapy drugs，contrast agent or lipiodol;
7. Any agents which could affect the absorption or pharmacokinetics of the study drugs
8. Subjects unable to suffer the discomfort of the artery infusion procedure