Background: Immunotherapy for stage IV melanoma has dramatically changed the overall prognosis and treatment strategies. The aim of this study was to evaluate whether changes in systemic immunotherapy options have significantly altered surgical resection rates for patients with stage IV melanoma.
Methods: The National Cancer Database (2004-2015) was used to perform a difference-in-difference analysis to evaluate whether the rate of surgical resection of metastatic disease for stage IV melanoma differed with the use of immunotherapy in the checkpoint inhibitor era in comparison with the use of immunotherapy in the pre-checkpoint inhibitor era. An adjusted difference-in-difference analysis stratified by facility type was performed. An adjusted Poisson regression analysis evaluated predictors of surgical resection in patients with stage IV melanoma who received immunotherapy.
Results: There were 14,433 patients with stage IV melanoma (median age, 66 years [interquartile range, 56-76 years]; female, 31.7%), and of all patients in the checkpoint inhibitor era (n = 7,524), 25% (n = 1,879) received immunotherapy. Patients with stage IV disease who received immunotherapy in the checkpoint inhibitor era were more likely to be younger, be healthier, have private insurance, come from upper income quartiles, and be treated at academic programs. A difference-in-difference analysis revealed similar rates of surgical resection of metastatic disease with the use of immunotherapy in the checkpoint inhibitor era and the pre-checkpoint inhibitor era, regardless of facility type.
Conclusions: The distribution of immunotherapy was unequal among patients with stage IV melanoma. Across all facilities, the rates of surgical resection of metastatic disease for stage IV melanoma did not differ with the use of immunotherapy between the checkpoint inhibitor era and the pre-checkpoint inhibitor era.
Keywords: checkpoint inhibitor era; immunotherapy; metastasectomy; pre-checkpoint inhibitor era; stage IV melanoma.
© 2020 American Cancer Society.