The abdominoperineal excision rate, a quality of care indicator in rectal cancer surgery, has been criticized if not adjusted for confounding factors.
Dr Freddy Penninckx and colleagues from Belgium evaluates variability in abdominoperineal excision rate between centers participating in PROCARE, a Belgian improvement initiative, before and after risk adjustment.
The team explored the effect of merging the Hartmann resections rate with that of abdominoperineal excision on benchmarking.
Data of 3197 patients who underwent elective radical resection for invasive rectal adenocarcinoma up to 15 cm were registered between 2006 and 2011 by 59 centers, each with at least 10 patients in the registry.
The research team analyzed variability of abdominoperineal excision or merged abdominoperineal excision/Hartmann resections rates between centers before and after adjustment for gender, age, ASA score, tumor level, depth of tumor invasion and preoperative incontinence.
The team found that the overall abdominoperineal excision rate was 21%.
|The overall abdominoperineal excision rate was 21%|
The doctors noted that significant variation of the abdominoperineal excision rate was observed before and after risk adjustment.
For cancers in the lower rectal third, the overall abdominoperineal excision rate increased to 46%.
Also, variation between centers increased.
The team of doctors found that risk adjustment influenced the identification of outliers.
Hazard ratios were performed in only about 3% of patients.
However, merging of risk adjusted abdominoperineal excision and hazard ratio rates identified other centers with outlying definitive colostomy rates than abdominoperineal excision rate alone.
Dr Penninckx 's team concluded, "Significant variation of the abdominoperineal excision rate was observed."
"Adjustment for confounding factors as well as merging hazard ratios with abdominoperineal excision rates were found to be important for the assessment of performances."