Association Between Oncology Clinical Pathway Utilization and Toxicity and Cost Outcomes in Patients With Metastatic Solid Tumors.

Purpose: This retrospective observational study compared cancer care toxicity and cost outcomes for patients with metastatic cancer with nine different cancer types prescribed on- versus off-pathway regimens.

Methods: This study used claims and authorization data from a national insurer between January 1, 2018, and October 31, 2021. Participants included adults with metastatic breast, lung, colorectal, pancreatic, melanoma, kidney, bladder, gastric, or uterine cancer, who were prescribed first-line anticancer regimens. Multivariable regressions were used to assess outcomes including counts of emergency room visits or hospitalizations, use of supportive care medications, immune-related adverse events (IRAEs), and health care costs.

Results: Of the 8,357 patients in the study, 5,453 (65.3%) were prescribed on-pathway regimens. The on-pathway proportion trended downward, from 74.3% in 2018 to 59.8% in 2021. The on- and off-pathway groups had a similar proportion of patients with treatment-related hospitalization (adjusted odds ratio [aOR], 1.080; = .201) and IRAEs (aOR, 0.961; = .497). More all-cause hospitalizations (aOR, 1.679; = .013) were observed among patients with melanoma treated on-pathway. The on-pathway group had higher use of supportive care drugs in bladder cancer (aOR, 4.602; < .001) and colorectal cancer (aOR, 4.465; < .001), and lower use in breast (aOR, 0.668; = .001) and lung cancer (aOR, 0.550; < .001). On average, on-pathway patients incurred $17,589 less total health care cost ( < .001), and $22,543 lower chemotherapy cost ( < .001) than those from the off-pathway group.

Conclusion: Our findings suggest that use of on-pathway regimens was associated with significant cost savings. Toxicity outcomes were variable by disease, but overall, there were similar numbers of treatment-related hospitalizations and IRAEs compared to off-pathway regimens. This cross-institutional study provides evidence to support the use of clinical pathway regimens for patients with metastatic cancer.