Receiving any other investigational agent which would be considered as a treatment for the primary neoplasm Receiving any other investigational agent that would be considered as a treatment for the primary neoplasm Primary surgeon indicates need for abdominoperineal (APR) at baseline Receiving any other investigational agent that would be considered a treatment for the primary neoplasm The participant has a primary brain tumor Patients with an immunodeficiency that existed prior to diagnosis such as primary immunodeficiency syndromes or organ transplant recipients are not eligible Group A will be further split into two subsets, which are mutually exclusive, for statistical purposes* Group A1:** > 6 months and < 12 months of age with an adrenal primary tumor < 5 cm in greatest diameter OR** Patients less than 6 months of age with an adrenal primary tumor > 3.1 and < 5 cm in greatest diameter OR** < 12 months of age with a non-adrenal primary site < 5 cm in greatest diameter* Group A2: =< 6 months of age with an adrenal primary site and tumor =< 3.1 cm in greatest diameter. Primary tumor site without progression at registration Progression of primary tumor site (breast, prostate, or lung) at time of registration Patients with an immunodeficiency that existed prior to diagnosis, such as primary immunodeficiency syndromes, organ transplant recipients and children on current systemic immunosuppressive agents are not eligible The primary tumor site must be controlled prior to registration* For those who present with synchronous primary and oligometastatic disease, primary must be controlled prior to registration* The definition of control is definitive surgery by excision or mastectomy (+/- radiotherapy) per institution preferenceFor those who present with local recurrence and oligometastatic disease, local recurrence must be controlled prior to registration* The definition of control is definitive surgery by excision or mastectomy (+/- radiotherapy) per institution preference Pathologic evidence of active primary disease or local/regional breast tumor recurrence at the time of registration; The subject has a primary brain tumor Patients with regional node involvement as their only site of disease beyond the primary tumor will not be eligible Patients with brain metastases from primary germ cell tumors, small cell carcinoma, unknown primary, or lymphoma The participant has a primary brain tumor Patients with primary refractory disease with progression of the primary tumor on initial therapy History of primary immunodeficiency Patients with primary oropharynx HNSCC must be HPV (-) according to local institutional definition using either p16 immunohistochemistry or HPV testing Carcinoma of the neck of unknown primary site origin (regardless of HPV/p16 status) is eligible Histologically confirmed melanoma of cutaneous primary; metastatic melanoma from unknown primary are allowed Patients with melanoma of mucosal or ocular primary For oropharynx primary tumors, the patient must have negative human papillomavirus (HPV) status of the tumor as determined by p16 protein expression using immunohistochemistry (IHC) (STEP 1) - PRIMARY INTERVENTION STUDY (RANDOMIZED CONTROLLED TRIAL [RCT]): Endocrine disorders (such as primary aldosteronism, pheochromocytoma, hyper- or hypothyroidism) not controlled with medication Patients that are determined to have a rare cancer with unknown primary site are eligible under cohort #32 (tumor of unknown primary [cancer of unknown primary; CuP]), provided that there is histologic documentation of metastatic malignancy with no discernible primary site identified from histopathologic review, physical exam and associated cross-sectional imaging of the chest, abdomen, and pelvis History of active primary immunodeficiency Patients must not have any history of primary immunodeficiency Patient must not have evidence of any clinically significant immunosuppression such as the following:* Primary immunodeficiency state such as severe combined immunodeficiency disease;* Concurrent opportunistic infection;* Receiving systemic immunosuppressive therapy (> 2 weeks) including oral steroid doses > 10 mg/day of prednisone or equivalent within 2 months prior to enrollment Patients with evidence of clinically significant immunosuppression such as the following are ineligible:* Primary immunodeficiency state such as severe combined immunodeficiency disease* Concurrent opportunistic infection* Receiving systemic immunosuppressive therapy (> 2 weeks) including oral steroid doses > 10 mg/day of prednisone or equivalent within 2 months prior to enrollment The trial is open only to women with primary endometrioid adenocarcinoma of the uterine corpus (all histologic grades and stages) who are planned and appropriate for primary surgical treatment