Time to treatment of esophageal cancer in Ontario: A population-level cross-sectional study

Abstract

Objective: Timely cancer treatment improves survival and anxiety for some sites. Patients with esophageal cancer require specific workup before treatment, which can prolong the time from diagnosis to treatment (treatment interval [TI]). The geographical variation of this interval remains uninvestigated in patients with esophageal cancer.

Methods: This retrospective population-level study conducted in Ontario used linked administrative health care databases. Patients treated for esophageal cancer between 2013 and 2018 were included. The TI was time from diagnosis to treatment. Patients were assigned a geographical Local Health Integration Network on the basis of postal code. Covariates included patient, disease, and diagnosing physician characteristics. Quantile regression modeled TI length at the 50th and 90th percentile and identified associated factors.

Results: Of 7509 patients, 78% were male and most were aged between 60 and 69 years. The 50th and 90th percentile TI was 36 (interquartile range, 22-55) and 77 days, respectively. The difference between the Local Health Integration Network with the longest and shortest TI at the 50th and 90th percentile was 18 and 25 days, respectively. Older age (P < .0001), greater comorbidity (P = .0005), greater material deprivation (P = .001), rurality (P = .03), histology (P = .02), and treatment group (P < .0001) were associated with a longer median TI. Older age (P = .03), greater comorbidity (P = .003), greater material deprivation (P = .005), rurality (P = .04), and treatment group (P < .0001) were associated with a longer 90th percentile TI.

Conclusions: Geographic variability of time to treatment exists across Ontario. Investigation of facility-level differences is warranted. Patient and disease factors are associated with longer wait times. These results might inform future health care policy and resource allocation.

Keywords: AC, adenocarcinoma; ADG, Aggregated Diagnosis Group; CIHI, Canadian Institute for Health Information; ED, Emergency Department; ICES, Institute for Clinical Evaluative Sciences; IQR, interquartile range; LHIN, Local Health Integration Network; NACRS, National Ambulatory Care Reporting System; OCR, Ontario Cancer Registry; PCCF, Postal Code Conversion File; SCC, squamous cell carcinoma; TI, treatment interval; epidemiology; esophageal cancer; geographical variability; treatment interval.

Graphical abstract

Geographical variability exists in the length of the esophageal cancer treatment interval.

Figure 1

Cohort creation. OHIP, Ontario Health Insurance Plan; ICES, Institute for Clinical Evaluative Sciences.

Figure 2

Box and whisker plot depicting the distribution of the Ontario esophageal cancer treatment interval between 2013 and 2018. Upper whisker = maximum observation excluding outliers; lower whisker = minimum observation excluding outliers; upper box bar = 75th percentile; lower box bar = 25th percentile; middle box bar = 50th percentile; dots = outliers (observations outside 1.5 times interquartile range).

Figure 3

Box and whisker plot showing the comparison of the esophageal cancer treatment interval length distribution among LHINs in Ontario between 2013 and 2018. Upper whisker = maximum observation excluding outliers; lower whisker = minimum observation excluding outliers; upper box bar = 75th percentile; lower box bar = 25th percentile; middle box bar = 50th percentile; dots = outliers (observations outside 1.5 times interquartile range). LHIN, Local Health Integration Network.

Figure 4

Different distributions of the esophageal cancer treatment interval length among Local Health Integration Networks in Ontario between 2013 and 2018. Upper whisker = maximum observation excluding outliers; lower whisker = minimum observation excluding outliers; upper box bar = 75th percentile; lower box bar = 25th percentile; middle box bar = 50th percentile; dots = outliers (observations outside 1.5 times interquartile range).