Palliative Quad Shot Radiation Therapy with or without Concurrent Immune Checkpoint Inhibition for Head and Neck Cancer.

Simple Summary: Immunotherapy represents the standard-of-care systemic therapy in patients with recurrent and metastatic head and neck cancer (HNC). However, these patients often present with local disease, which can affect quality of life, and local progression can lead to significant morbidity. Local response rates from immunotherapy alone are subpar. Thus, palliative radiation is often utilized in this scenario. 'QuadShot'(QS), a hypofractionated palliative radiation regimen, can provide symptomatic relief and local control and may potentiate the effects of immunotherapy. There have been no previous studies evaluating the combination of immunotherapy with QS. We found that the combination of QS with concurrent immunotherapy was well tolerated and significantly improved local control compared to QS alone. The median survival of 9.4 months compares favorably to historical controls for patients with HNC treated with QS. This approach represents a promising treatment option for patients with HNC unsuited for curative-intent treatment and warrants prospective evaluation. Objectives: Patients with recurrent and metastatic head and neck cancer (HNC) have limited treatment options. 'QuadShot' (QS), a hypofractionated palliative radiotherapy regimen, can provide symptomatic relief and local control and may potentiate the effects of immune checkpoint inhibitors (ICIs). We compared outcomes of QS ± concurrent ICIs in the palliative treatment of HNC. Materials and Methods: We identified patients who received ≥three cycles of QS from 2017 to 2022 and excluded patients without post-treatment clinical evaluation or imaging. Outcomes for patients who received QS alone were compared to those treated with ICI concurrent with QS, defined as receipt of ICI within 4 weeks of QS. Results: Seventy patients were included, of whom 57% received concurrent ICI. Median age was 65.5 years (interquartile range [IQR]: 57.9–77.8), and 50% patients had received prior radiation to a median dose of 66 Gy (IQR: 60–70). Median follow-up was 8.8 months. Local control was significantly higher with concurrent ICIs (12-month: 85% vs. 63%, p = 0.038). Distant control (12-month: 56% vs. 63%, p = 0.629) and median overall survival (9.0 vs. 10.0 months, p = 0.850) were similar between the two groups. On multivariable analysis, concurrent ICI was a significant predictor of local control (HR for local failure: 0.238; 95% CI: 0.073–0.778; p = 0.018). Overall, 23% patients experienced grade 3 toxicities, which was similar between the two groups. Conclusions: The combination of QS with concurrent ICIs was well tolerated and significantly improved local control compared to QS alone. The median OS of 9.4 months compares favorably to historical controls for patients with HNC treated with QS. This approach represents a promising treatment option for patients with HNC unsuited for curative-intent treatment and warrants prospective evaluation. [ABSTRACT FROM AUTHOR]