This phase I/II trial studies the side effects, safety, and effectiveness of low dose radiation to the entire body (total body irradiation \[TBI\]) and higher dose radiation to known areas of cancer (hypofractionated radiation therapy \[H-RT\]) combined with atezolizumab and chemotherapy (carboplatin \& etoposide) in treating patients with small cell lung cancer that has spread to disease sites outside of the lung (extensive stage). Extensive stage disease has historically been treated with chemotherapy alone with consideration of chest (thoracic) radiation therapy for those with response to chemotherapy, as well as consideration of preventative radiation therapy to the head (prophylactic cranial irradiation). Emerging evidence supports the synergistic interactions between immunotherapy and radiation therapy. Immunotherapy with monoclonal antibodies, such as atezolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Carboplatin is in a class of medications known as platinum-containing compounds. It works in a way similar to the anticancer drug cisplatin, but may be better tolerated than cisplatin. Carboplatin works by killing, stopping or slowing the growth of tumor cells. Etoposide is in a class of medications known as podophyllotoxin derivatives. It blocks a certain enzyme needed for cell division and DNA repair and may kill tumor cells. Combining TBI and H-RT with atezolizumab and chemotherapy may improve response to treatment.

This phase I trial tests the safety, side effects, and best dose of triapine in combination with radiation therapy in treating patients with glioblastoma or astrocytoma that has come back after a period of improvement (recurrent). Triapine may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Radiation therapy uses high energy x-rays, particles, or radioactive seeds to kill cancer cells and shrink tumors. Giving triapine in combination with radiation therapy may be safe, tolerable, and/or effective in treating patients with recurrent glioblastoma or astrocytoma.

The purpose of the study is to evaluate the safety and survival of carmustine wafers and radiation and retifanlimab with or without temozolomide (TMZ) in newly-diagnosed adult subjects with glioblastoma multiform after carmustine wafer placement.

This phase II trial studies the effect of pembrolizumab alone compared to the usual approach (chemotherapy \[cisplatin and carboplatin\] plus radiation therapy) after surgery in treating patients with head and neck squamous cell carcinoma that has come back (recurrent) or patients with a second head and neck cancer that is not from metastasis (primary). Radiation therapy uses high energy radiation or protons to kill tumor cells and shrink tumors. Cisplatin is in a class of medications known as platinum-containing compounds. It works by killing, stopping or slowing the growth of cancer cells. Carboplatin is also in a class of medications known as platinum-containing compounds. It works in a way similar to the anticancer drug cisplatin, but may be better tolerated than cisplatin. Carboplatin works by killing, stopping or slowing the growth of cancer cells. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer and may interfere with the ability of tumor cells to grow and spread. Giving pembrolizumab alone after surgery may work better than the usual approach in shrinking recurrent or primary head and neck squamous cell carcinoma.

This phase I/II trial studies the safety, side effects and best dose of M3814 and to see how well it works when given together with radiation therapy in treating patients with pancreatic cancer that has spread to nearby tissue or lymph nodes (locally advanced). M3814 may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Hypofractionated radiation therapy delivers higher doses of radiation therapy over a shorter period of time and may kill more tumor cells and have fewer side effects. Giving M3814 and hypofractionated radiation therapy together may be safe, tolerable and/or more effective than radiation therapy alone in treating patients with locally advanced pancreatic cancer.