Neoadjuvant Nivolumab + Relatlimab (Opdualag) Versus Nivolumab for Resectable High-Risk Basal Cell Carcinoma

Inclusion Criteria: 1. Ability to understand and the willingness to sign a written informed consent document. 2. Participants must have histologically or cytologically confirmed basal cell carcinoma. 3. Participants must have high risk BCC as defined by size 20 mm or greater in the head and neck region or 40 mm or greater for the trunk/extremities. 4. Participants must have surgically resectable BCC that is at increased risk for cosmetic disfigurement, functional defects, poor oncologic control, or anticipated to require skin grafting or free flap reconstruction per investigator assessment. 5. Participants must have treatment naive BCC. 6. Aged 18 years or older. 7. Eastern Cooperative Oncology Group Performance Status 0 or 1 8. Demonstrates adequate organ function as defined below: Adequate bone marrow function 1. Absolute neutrophil count ≥ 1,500/microliter 2. Platelets ≥ 100,000/microliter Adequate hepatic function 3. Total bilirubin \>1.5 x institutional upper limit of normal (except participants with Glibert Syndrome who must have a total bilirubin level of \<3.0xULN) 4. Aspartate aminotransferase (AST or SGOT) ≤ 3 x institutional upper limit of normal 5. Alanine transaminase (ALT or SGPT) ≤ 3 x institutional upper limit of normal Adequate renal function 6. Creatinine clearance Calculated creatinine clearance (CrCl) \> 30 mL/min (using the Cockcroft Gault formula) 9. Human immunodeficiency virus (HIV) infected individuals on effective anti retroviral therapy with undetectable viral load within 6 months are eligible for this trial. Patients must not have had an AIDS defining opportunistic infection within the last year or a current CD4 count \< 350 cells/microliter. 10. For participants with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated. 11. Individuals with a history of hepatitis C virus (HCV) infection must have been treated and cured. For individuals with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load. 12. Concurrent malignancy (present during screening) requiring treatment or history o f prior malignancy active within 2 years prior to randomization (i.e., participants with a history of prior malignancy are eligible if treatment was completed at least 2 years before randomization and the patient has no evidence of disease). Participants with history of prior early stage basal/squamous cell skin cancer or non invasive or in situ cancers that have undergone definitive treatment at any time are also eligible. 13. The effects of Opdualag on the on the developing human fetus are unknown. Therefore, the following criteria apply to participants in each study arm: Cohort 1 Opdualag: A woman of child bearing potential (WOCBP) is eligible to enroll if using a contraceptive method that is highly effective (with a failure rate of \< 1% per year), with low user dependency, during the intervention period and for the duration of treatment with Opdualag plus 5 half lives of study treatment for a total of 5 months post treatment completion and agrees not to donate eggs (ova, oocytes) for the purpose of re production for the same time period. Cohort 2 nivolumab: i. Women who are not of childbearing potential are exempt from contraceptive requirements. ii. Women participants must have documented proof that they are not of childbearing potential. iii. Women of child bearing potential (WOCBP) must have a negative serum or urine pregnancy test (minimum sensitivity 25 IU/L or equivalent units of human chorionic gonadotropin) within 24 hours prior to the start of study treatment. An extension up to 72 hours prior to the start of study treatment is permissible in situations where results cannot be obtained within the standard 24 hour window. iv. Additional requirements for pregnancy testing during and after study intervention are located in the Schedule of Assessments. v. The investigator is responsible for review of medical history, menstrual history, and recent sexual activity to decrease the risk for inclusion of a woman with an early undetected pregnancy. vi. WOCBP must agree to follow instructions for method(s) of contraception and as described below and included in the Informed Consent Form. vii. WOCBP are permitted to use hormonal contraception methods viii. A female participant is eligible to participate if she is not pregnant or breastfeeding, and at least one of the following conditions applies: 1. Is not a WOCBP. OR 2. Is a WOCB P and using a contraceptive method that is highly effective (with a failure rate of \<1% per year), with low user dependency, during the intervention period and for at least 5 months and agrees not to donate eggs (ova, oocytes) for the purpose of reproduction for the same time period. Exclusion Criteria: 1. Is currently receiving any other investigational agents. 2. Has participated in a study of an investigational product and received study treatment or used an investigational device within 4 weeks of the first dose of study treatment. 3. Hypersensitivity to Opdualag, nivolumab, or any of their excipients. 4. Presence of untreated (symptomatic) central nervous system metastases. 5. Presence of leptomeningeal metastatic disease. 6. Treatment with any live / attenuated vaccine within 30 days of first study treatment. 7. Radiation therapy within 2 weeks prior to first study treatment. Participants must have recovered (i.e., Grade ≤1 or at baseline) from radiation related toxicities prior to first study treatment. 8. Participants with a condition requiring systemic treatment with either corticosteroids (\> 10 mg daily prednisone equivalent) within 14 days or other immunosuppressive medications within 30 days of randomization. Note: Inhaled or topical steroids, and adrenal replacement steroid doses \> 10 mg daily prednisone equivalent, are permitted in the absence of active autoimmu