Radiotherapy in Combination With Atezolizumab in Locally Advanced Borderline Resectable or Unresectable Cutaneous SCC

Inclusion Criteria: * Histologically or cytologically confirmed locally advanced borderline resectable or unresectable cSCC and oligometastatic (1-3 sites of metastatic disease) cSCC receiving therapy to the primary * Measurable disease defined as lesions that can be accurately measured in at least one dimension (longest diameter to be recorded) as \> 10 mm with computed tomography (CT) scan or \> 10 mm with calipers by clinical exam by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 * Written informed consent and any locally-required authorization (e.g., Health Insurance Portability and Accountability Act \[HIPAA\] in the United States of America \[USA\], European Union \[EU\] Data Privacy Directive in the EU) obtained from the patient prior to performing any protocol-related procedures, including screening evaluations * Age \>= 18 years at time of study entry * Eastern Cooperative Oncology Group (ECOG) performance status =\< 1 * Life expectancy \>= 24 weeks * Body weight \> 30 kg * Hemoglobin \>= 9.0 g/dL * Absolute neutrophil count (ANC) \>= 1.0 x 10\^9/L (\>= 1000 per mm\^3) * Platelet count \>= 75 x 10\^9/L (\>= 75,000 per mm\^3) * Serum bilirubin =\< 1.5 x institutional upper limit of normal (ULN). This will not apply to patients with confirmed Gilbert's syndrome (persistent or recurrent hyperbilirubinemia that is predominantly unconjugated in the absence of hemolysis or hepatic pathology), who will be allowed only in consultation with their physician * Aspar…