Personalized Radiotherapy for Individualized Treatment Strategies and Monitoring (PRISM)

Inclusion Criteria:

Cohort A:

* \>=18 years old
* Performance status ECOG 0-2
* Extensive stage small cell lung cancer diagnosed by tissue biopsy within 180 days of registration.
* Patient must be planned for or receiving standard of care chemoimmunotherapy.
* Patient must have received no more than 3 cycles by time of study enrollment.
* Able and indicated according to investigator to receive thoracic radiotherapy

Cohort B:

* 18 years old
* Diagnosis of solid tumor malignancy with MRI-defined brain metastasis lesions within 60 days of registration
* Each brain metastasis lesion enrolled must be 2 - 5 cm, except brainstem lesions which may be 1.5 - 5cm in size.

Cohort C:

* \>=18 years old
* Performance status ECOG 0-2
* Histologically confirmed surgically resectable, high grade (FNCLCC grade 2 or 3), localized soft tissue sarcoma of the trunk or extremities that measures \>5 cm in any direction as assessed by imaging
* Eligible to receive immunotherapy

Cohort D:

* \>=18 years old
* Performance status ECOG 0-2
* Pathologically proven diagnosis of squamous cell carcinoma of the oral cavity, oropharynx, larynx, or hypopharynx
* Clinical stage III/IVA (AJCC 8th edition)
* Disease must be deemed resectable by head and neck surgeon
* Eligible to receive immunotherapy

Exclusion Criteria:

Cohort A:

⨀ Prior thoracic Radiotherapy

Cohort B:

* Prior whole brain Radiotherapy
* Prior surgical resection or focal radiotherapy of a target brain metastasis
* Leptomeningeal disease

Cohort C:

* Unresectable or metastatic (nodal or distant) disease
* Synchronous malignancy requiring chemotherapy or other intensive treatment
* Locally recurrent soft tissue sarcoma
* Prior immunotherapy
* Pregnancy or breastfeeding

Cohort D:

* Distant metastasis
* Inability to undergo PET-CT for baseline staging
* HPV-positive or p16-positive oropharyngeal cancer
* Prior systemic chemotherapy for the study cancer; prior chemotherapy for a remote cancer is allowable
* Prior immunotherapy for the study cancer or for a remote cancer
* Prior head and neck radiotherapy