Polatuzumab Vedotin, Rituximab, Ifosfamide, Carboplatin, and Etoposide (PolaR-ICE) as Initial Salvage Therapy for the Treatment of Relapsed/Refractory Diffuse Large B-Cell Lymphoma

Inclusion Criteria: * Documented informed consent of the participant and/or legally authorized representative * Assent, when appropriate, will be obtained per institutional guidelines * Be willing to provide archival tissue of a biopsy that was performed after the frontline systemic therapy * If unavailable, exceptions may be granted with study principal investigator (PI) approval * Eastern Cooperative Oncology Group (ECOG) =\< 2 * Histologically confirmed diagnosis of diffuse large B-cell lymphoma according to the World Health Organization (WHO) classification, with hematopathology review at the participating institution. Subtypes of DLBCL including transformed indolent lymphomas (TIL), primary mediastinal large B-cell lymphoma (PMBCL), and aggressive B-cell lymphoma unclassified (BCL-U) are eligible * Biopsy-proven relapsed or refractory disease after 1 line of frontline CD20-directed immunotherapy with anthracycline- or anthracenedione-based multi-agent chemotherapy. Monotherapy with rituximab or other CD20-directed immunotherapy prior to frontline chemotherapy or as maintenance therapy, and radiation therapy in a limited field or as a part of the frontline treatment plan are permitted * Prior lymphoma therapy should be completed at least 2 weeks before start of protocol therapy * Measurable disease by computed tomography (CT) or positron emission tomography (PET)/CT scan with one or more sites of disease \>= 1.5 cm in longest dimension * Considered eligible for hig…