Definition: The percentage of stage II or III rectal cancer cases receiving pre-operative radiation therapy up to 120 days before resections within one year of diagnosis
Rationale for measurement: The delivery of radiation therapy (along with chemotherapy) prior to surgical resection for Stage II and III rectal cancer has been shown to improve local disease control compared with surgery alone or post-operative radiation therapy. Also, it has been associated with a reduction in treatment-related toxicity compared with post-operative radiation therapy. Clinical practice guidelines therefore recommend pre-operative radiation therapy (combined with chemotherapy) for patients with Stage II and III rectal cancer.
Measurement timeframe: Diagnoses years 2011 to 2014
Denominator: Stage II and III rectal cancer cases diagnosed during the timeframe and receiving rectal resection within one year of diagnosis
Numerator: Stage II and III rectal cancer cases diagnosed during the timeframe and receiving pre-operative radiation therapy up to 120 days before resection within one year of diagnosis
Exclusion criteria: Cases with age ≤ 17 were excluded
Data availability:
2011-2014: AB, MB, NB, NS, PE, NL
2011-2013: BC
Stratification:
By year
By province
Data source: Provincial cancer agencies and programs
Data retrieval date: October 2017
Variables details:
Cancer definition:
Rectal cancer was defined as C20.9 in ICD-O3 with behavior code 3 (invasive)For cancer cases with lymphoma Codes M-95 to M-98, sarcoma codes (see Appendix A), neuroendocrine carcinoma and squamous cell carcinoma were excluded
Rectal cancer cases were restricted to stage II and stage III in American Joint Committee on Cancer (AJCC).
Resection identification:
Rectal resections were identified in CCI codes as 1NQ87 or 1NQ89. CCI code 1NQ87BA was excluded.
Treatment criteria:
All rectal resections were within 1 year of diagnosis. If there were multiple resections, the first resection was counted:
First resection date (if multiple) – diagnosis date ≤ 365 days
All pre-operative radiation therapies were up to 120 days before resections. If there were multiple resections, the first resection was counted.
First resection date – Radiation therapy date ≤120 days
Notes from jurisdictions:
BC: We do not have surgery data past 2014 and since the indicator includes surgery up to 1 year following diagnosis, we cannot provide data for diagnosis year 2014.
NB: 2010/2011 radiation treatment may be incomplete.
PE: Did not have data on whether the resection margins were negative so cannot comment either way.
Methodology notes:
Data presented include stage II and III combined
The cancer incidence sites/types were classified by World Health Organization, International Classification of Diseases for Oncology, Third Edition (ICD- O-3).
American Joint Committee on Cancer (AJCC) Cancer Staging Manual 7th edition was used to classify cancer stage groups.
The Canadian Classification of Health Interventions (CCI) codes were used to identify surgery types, except AB.
Changes to definition compared to previous years: Resections with negative margin were not required.
