A Study of Anlotinib in Recurrent/Metastatic Head and Neck Adenocarcinomas

1. Histologically or cytologically confirmed head and neck adenocarcinoma.
2. Patients with recurrent or metastatic head and neck adenocarcinoma who are not candidates for curative surgery or radiotherapy.
3. Measurable disease per the RECIST criteria.
4. Eastern Cooperative Oncology Group (ECOG) performance status 0-2.
5. Provision of written informed consent.
6. Childbearing potential either terminated by surgery, radiation, or menopause, or attenuated by use of an approved contraceptive method (IUD, birth control pills, or barrier device) during and for 3 months after completion of trial therapy.

Exclusion Criteria:

1. Prior treatment with Anlotinib
2. With pleural effusion or ascites, cause respiratory syndrome
3. Accepted the vascular endothelial growth inhibitor class targeted drug treatment of patients
4. Plan to take systemic anti-tumor therapy within 4 weeks before grouping or during the medicine-taking period of this research, including Cytotoxic Therapy, 5.Signal Transduction Inhibitor, and Immunotherapy (or who use Mitomycin C within 6 weeks before taking the treatment with experimental drug); The patients who have already taken Extended Field Radiotherapy (EF-RT) within 4 weeks before grouping or Limited Field Radiotherapy with proposed assessment of nidus within 2 weeks before grouping

6.Symptoms of brain metastases cannot be controlled and treated within less than 2 months 7.severe and failed to controlled diseases 8.Occurred venous thromboembolic events within 6 months