Lattice Radiotherapy for Adults With Large Tumors

The purpose of this study is to ask whether using a specialized radiation therapy technique called Lattice Radiation Therapy (LRT) can shrink large tumors when given with palliative radiation therapy. The primary questions are: * if LRT is safe and does not worsen existing side effects or cause new side effects * if adding LRT to standard radiation therapy can improve tumor shrinkage. Participants will have one additional radiation treatment (LRT) prior to starting palliative radiation and then their progress will be followed for one year.

Inclusion Criteria: * Histologically or cytologically confirmed malignancy diagnosis * Radiographic evidence of large extracranial tumor (≥ 4.5 cm) * Patients with primary or metastatic extracranial tumors may be included * Planned to undergo palliative radiation treatment * Life expectancy of at least 3 months * ECOG performance status ≤ 3 * Patient must sign study-specific informed consent Exclusion Criteria: * Primary lesion with radiosensitive histology (i.e. germ cell tumors, lymphoma, leukemia, and multiple myeloma) * Prior radiation treatment that overlaps with any planned site of protocol radiotherapy that would preclude further palliative RT. * Receiving concurrent cytotoxic cancer therapy regimens or VEGF inhibitor that would overlap with LRT administration. Cytotoxic chemotherapy, targeted therapies, small molecule inhibitors, or sVEGF inhibitors prior to radiation treatment or planned after radiation delivery are allowed at the discretion of the treating radiation oncologist.