Interruptions of Head and Neck Radiotherapy Across Insured and Indigent Patient Populations

Radiotherapy for head and neck cancer is a cornerstone of care, requiring 30 to 35 days of treatment over 6 to 7 weeks. Diligent patient compliance is crucial, and unplanned treatment interruptions reduce cure rates. We studied interruption rates in private carrier-insured and Medicare-insured populations versus indigent populations served by a single academic health system.

A retrospective cohort study of electronic medical and billing records was performed analyzing treatment interruptions between January 2011 and December 2014. The study included 564 patients with head and neck cancer prescribed radiotherapy and referred from clinics run by University of Texas Southwestern Medical Center (UTSW) and the Parkland Health and Hospital System (PHHS), which provides indigent care to Dallas County, Texas.

Three-hundred sixteen patients (56%) had a treatment break; 114 patients missed a single session, and 202 patients missed multiple treatments. Seventy percent of PHHS patients had treatment delays compared with 47% of UTSW patients ( P < .001). The number of interrupted days in the PHHS population was nearly twice that observed in UTSW patients. PHHS patients most commonly missed treatment for nonmedical or logistical reasons. Delay was predictive for local recurrence ( P < .001) and overall survival ( P < .001). In compliant patients, there was no significant difference in local recurrence ( P = .43) or overall survival ( P = .27) across referral sites. However, among noncompliant patients, there was a higher likelihood for local recurrence in the PHHS cohort ( P = .016). Multivariable modeling suggested treatment interruption to be a key driver of outcome differences across referral sites.

Survival outcomes in our at-risk population were inferior to those in patients insured by commercial carriers or Medicare. Treatment interruption predicted for poor outcome across all patients but was disproportionately experienced by at-risk patients. These results highlight cancer control needs specific to disadvantaged communities at risk for poor treatment compliance.