"This phase I trial investigates the effect of radiation therapy on the immune system, specifically CD8 positive (+) T cells, in lymphoma patients receiving bridging radiation therapy before CAR T-cell infusion, and metastatic patients with solid tumor malignancies receiving SBRT. CD8+ T cells are mainly found in lymph tissue and play a significant role in anti-tumor immunity. These cells can infiltrate tumor cells and kill them. Radiation therapy may recruit CD8 T cells and this recruitment may help with tumor control. Diagnostic procedures, such as zirconium Zr 89-Df-crefmirlimab positron emission tomography (PET), may be a less invasive way to check and monitor for CD8+ T cells before and after radiation therapy."

PRIMARY OBJECTIVE:

I. Evaluate if there is an increase in CD8+ T cells after stereotactic body radiation therapy (SBRT) in irradiated tumors.

SECONDARY OBJECTIVES:

I. To report on the time evolution of zirconium Zr 89-Df-crefmirlimab (CD8 PET tracer) uptake after infusion.

II. To compare CD8 PET tracer uptake at irradiated lesions to uptake at non-irradiated lesions (if any).

III. To assess how differences in site, histology and/or prior therapy relate to immune characterization and changes IV. To assess serum biomarkers of immune response before and after SBRT. V. To assess ability of CD8 PET tracer and imaging to be a biomarker of SBRT. VI. Evaluate CD8 PET tracer with Response Evaluation Criteria in Solid Tumors (RECIST) radiology measurements.

VII. To report any adverse events associated with 2 doses of CD8 PET tracer when used in combination with SBRT.

EXPLORATORY OBJECTIVE:

I. Blood will be collected, processed, and stored for future immune profiling or other correlatives pending additional funding.

II. Evaluate the safety and feasibility of using CD8 PET imaging to assess immune system activation during and after bRT for CAR T cell therapy.

III. Describe the CD8 PET tracer uptake prior to CAR T and the response/duration of response to CAR T cell therapy

OUTLINE:

Patients receive zirconium Zr 89-Df-crefmirlimab intravenously (IV) over 5-10 minutes and then undergo PET imaging 24 hours after infusion before and after SBRT. Patients undergo SBRT every 2-5 days for a total of 5 fractions.

The subset of lymphoma patients enrolled on trial who are being treated in the bridging radiation setting before CAR T-cell therapy will receive 3 infusions of Zr89-Df-crefmirlimab and associated CD8 ImmunoPET imaging before radiation, after radiation, and after CAR T-cell infusion.

After completion of study treatment, patients are followed up at 4-6 weeks, 3 months, 1 year, and then periodically for 2 years.

Inclusion Criteria:

• Documented informed consent of the participant and/or legally authorized representative

• Participant is willing and able to comply with all protocol required procedures

• Age: >= 18 years

• Eastern Cooperative Oncology Group (ECOG) =< 2

• Metastatic patients of any solid tumor malignancy amenable for SBRT as determined by the radiation oncologist

• Lymphoma patients may be allowed as determined by the principal investigator (PI)

• No change in systemic treatment regimen for past 2 months prior to start of SBRT

• Patients able to comply with daily PET after SBRT

• Patient meets all clinical safety lab values per institution's standard of care, or Investigator's discretion, for patients receiving cancer treatment

• Women of childbearing potential (WOCBP): 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

• Agreement by females and males of childbearing potential to use effective double barrier contraceptive methods or abstain from heterosexual activity for the course of the study through at least 30 days after the last administration of the CD8 PET tracer

  • Childbearing potential defined as not being surgically sterilized (men and women) or have not been free from menses for > 1 year (women only)

Exclusion Criteria:

• Patient who have splenic disorders or had splenectomy that per PI would interfere with CD8 imaging

• Patients should not have any uncontrolled illness including ongoing or active infection

• History of allergic reactions attributed to compounds of similar chemical or biologic composition to CD8 PET tracer

• Serious nonmalignant disease or conditions that could compromise protocol objectives, in the opinion of the investigator

• Females only: Pregnant or breastfeeding

  • Pregnant women are excluded from this study because CD8 PET tracer is an agent with the potential for teratogenic or abortifacient effects. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with CD8 PET tracer, breastfeeding should be discontinued if the mother is treated with CD8 PET tracer

• Any other condition that would, in the Investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns with clinical study procedures

• Prospective participants who, in the opinion of the investigator, may not be able to comply with all study procedures (including compliance issues related to feasibility/logistics)