Chemoimmunotherapy

Chemoimmunotherapy refers to cancer treatment that combines chemotherapy with immunotherapy to enhance antitumor activity. It can be given at the same time (concurrent therapy) or in sequence, depending on the cancer type and regimen. The goal is to leverage the cytotoxic effects of chemotherapy while boosting the immune system's ability to recognize and attack tumor cells.

Chemotherapy uses cytotoxic drugs that kill rapidly dividing cells but can also modulate the tumor microenvironment. Immunotherapy includes immune checkpoint inhibitors (such as antibodies against PD-1, PD-L1, or CTLA-4), monoclonal antibodies, adoptive cell therapies, vaccines, and cytokines. In chemoimmunotherapy, chemotherapy may increase tumor antigen release and improve antigen presentation, reduce immunosuppressive cell populations, and create inflammatory conditions that improve immune recognition. In turn, immunotherapy may sustain and broaden the immune response against cancer cells that survive chemotherapy.

A classic example in hematologic cancer is adding rituximab to standard chemotherapy regimens (such as CHOP) for B-cell lymphomas. In solid tumors, concurrent or sequential regimens pairing platinum-based chemotherapy with checkpoint inhibitors have become standard in some settings (for example, non-small cell lung cancer and urothelial carcinoma), though regimens vary by diagnosis and approved indications.

Outcomes and risks: Chemoimmunotherapy can yield higher response rates and longer progression-free survival in selected patients relative to chemotherapy alone, but it often carries greater toxicity, including immune-related adverse events, cytopenias, infection risk, and organ-specific toxicity. Management requires careful patient selection, monitoring, and multidisciplinary care.

Research status: Ongoing trials explore optimal sequencing, dosing, biomarkers to predict benefit, and expansions to additional cancer types. Decisions are individualized based on tumor type, stage, patient comorbidities, and prior therapies.