Radiation Therapy and MK-3475 for Patients With Recurrent/Metastatic Head and Neck Cancer, Renal Cell Cancer, Melanoma, and Lung Cancer

Inclusion Criteria: 1. Be willing and able to provide written informed consent/assent for the trial. 2. Be ≥ 18 years of age on day of signing informed consent. 3. Have provided tissue from an archival tissue sample ( \< 6 months old) or newly obtained core biopsy of a tumor lesion before radiation therapy. A core biopsy will be required. It is mandatory to have post-radiation re-biopsy. 4. In addition to index lesion, there are ≥ 1 measurable lesion(s). 5. Have a performance status of ≤ 1 on the ECOG Performance Scale. 6. Demonstrate adequate organ function defined as the following: * Absolute neutrophil count (ANC) ≥1,500 /mcL * Platelets ≥100,000 / mcL * Hemoglobin ≥9 g/dL or ≥5.6 mmol/L * Serum creatinine OR Measured or calculated creatinine clearance (GFR can also be used in place of creatinine or CrCl) ≤1.8 X upper limit of normal (ULN) OR ≥50 mL/min for subject with creatinine levels \> 1.8 X institutional ULN * Serum total bilirubin ≤ 1.5 X ULN OR direct bilirubin ≤ ULN for subjects with total bilirubin levels \> 1.5 ULN * AST (SGOT) and ALT (SGPT) ≤ 2.5 X ULN OR ≤ 5 X ULN for subjects with liver metastases 7. Female subjects of childbearing potential should have a negative urine or serum pregnancy test. If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required. 8. Female subjects of childbearing potential should be willing to use 2 methods of birth control or be surgically sterile, or abstain from heterosexual activity for the course of the study through 120 days after the last dose of study medication (Reference Section 5.7.2). Subjects of childbearing potential are those who have not been surgically sterilized or have not been free from menses for \> 1 year. 9. Male subjects should agree to use an adequate method of contraception starting with the first dose of study therapy through 120 days after the last dose of study therapy. Exclusion Criteria: 1. Is currently participating in or has participated in a study of an investigational agent or using an investigational device within 2 weeks of the radiation therapy. 2. Has a diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the radiation therapy. 3. Has had a prior monoclonal antibody within 4 weeks prior to radiation therapy or who has not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due to agents administered more than 4 weeks earlier. 4. Has had prior chemotherapy, targeted small molecule therapy, or radiation therapy within 2 weeks prior to radiation therapy or who has not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due to a previously administered agent. * Note: Prior radiation therapy does not necessary excludes patients. The index lesion may be acceptable for stereotactic radiosurgery (SRS) and this will be determined by radiation oncologist. * Note: If there are more than one symptomatic lesions, patients will be excluded if the lesions can't be encompassed within one radiation portal. * Note: Subjects with ≤ Grade 2 neuropathy are an exception to this criterion and may qualify for the study. * Note: If subject received major surgery, they must have recovered adequately from the toxicity and/or complications from the intervention prior to starting therapy. 5. Has a known additional malignancy that is progressing or requires active treatment. Exceptions include basal cell carcinoma of the skin, squamous cell carcinoma of the skin, superficial bladder cancer or in situ cervical cancer that has undergone potentially curative therapy. 6. Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis. Subjects with previously treated brain metastases may participate provided they are stable (without evidence of progression by imaging for at least four weeks prior to the radiation therapy and any neurologic symptoms have returned to baseline), have no evidence of new or enlarging brain metastases, and are not using steroids for at least 7 days prior to radiation treatment. 7. Has an active autoimmune disease requiring systemic treatment within the past 3 months or a documented history of clinically severe autoimmune disease, or a syndrome that requires systemic steroids or immunosuppressive agents. Subjects with vitiligo or resolved childhood asthma/atopy would be an exception to this rule. Subjects that require intermittent use of bronchodilators or local steroid injections would not be excluded from the study. Subjects with hypothyroidism stable on hormone replacement or Sjorgen's syndrome will not be excluded from the study. 8. Has evidence of interstitial lung disease or active, non-infectious pneumonitis. 9. Has an active infection requiring systemic therapy. 10. Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the trial, interfere with the subject's participation for the full duration of the trial, or is not in the best interest of the subject to participate, in the opinion of the treating investigator. 11. Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial. 12. Is pregnant or breastfeeding, or expecting to conceive or father children within the projected duration of the trial, starting with the pre-screening or screening visit through 120 days after the last dose of trial treatment. 13. Has received prior therapy with an anti-PD-1, anti-PD-L1, anti-PD-L2, anti-CD137, or anti-Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) antibody (including ipilimumab or any other antibody or drug specifically targeting T-cell co-stimulation or checkpoint pathways). 14. Has a known Human Immunodeficiency Virus infection (HIV 1/2 antibodies) or Acquired Immunodeficiency Syndrome((HIV/AIDS). 15. Has known active Hepatitis B (e.g., HBsAg reactive) or Hepatitis C (e.g., HCV RNA \[qualitative\] is detected). 16. Has received a live vaccine within 30 days prior to the radiation therapy.