Retrospective review of rectal cancer surgery in northern Alberta.

INTRODUCTION: Previous studies, including research published more than 10 years ago in Northern Alberta, have demonstrated improved outcomes with increased surgical volume and subspecialisation in the treatment of rectal cancer. We sought to examine contemporary rectal cancer care in the same region to determine whether practice patterns have changed and whether outcomes have improved. METHODS: We reviewed the charts of all patients with rectal adenocarcinoma diagnosed between 1998 and 2003 who had a potentially curative resection. The main outcomes examined were 5-year local recurrence (LR) and disease-specific survival (DSS). Surgeons were classified into 3 groups according to training and volume, and we compared outcome measures among them. We also compared our results to those of the previous study from our region. RESULTS: We included 433 cases in the study. Subspecialty-trained colorectal surgeons performed 35% of all surgeries in our study compared to 16% in the previous study. The overall 5-year LR rate and DSS in our study were improved compared to the previous study. On multivariate analysis, the only factor associated with increased 5-year LR was presence of obstruction, and the factors associated with decreased 5-year DSS were high-volume noncolorectal surgeons, presence of obstruction and increased stage. CONCLUSION: Over the past 10 years, the long-term outcomes of treatment for rectal cancer have improved. We found that surgical subspecialization was associated with improved DSS but not LR. Increased surgical volume was not associated with LR or DSS.

CONTEXTE: Des études antérieures, y compris des recherches menées dans le nord de l'Alberta et publiées il y a plus de 10 ans, ont montré une amélioration des résultats associée à un volume chirurgical accru et à la surspécialisation dans le traitement du cancer rectal. Nous avons voulu constater le traitement actuel du cancer rectal dans cette même région pour déterminer si les modes de pratique ont évolué et si les résultats se sont améliorés. MÉTHODES: Nous avons passé en revue les dossiers de tous les patients porteurs d'un adénocarcinome du rectum diagnostiqué entre 1998 et 2003 qui ont subi une résection à visée curative. Les principaux paramètres analysés ont été la récurrence locale (RL) et la survie spécifique à la maladie (SSM) à 5 ans. Nous avons réparti les chirurgiens en 3 groupes selon leur formation et leur volume d'interventions et nous avons comparé les résultats entre eux. Nous avons aussi comparé nos résultats à ceux de l'étude précédente réalisée dans notre région. RÉSULTANTS: Nous avons inclus 433 cas dans l'étude. Les chirurgiens spécialisés en intervention colorectale ont effectué 35% de toutes les chirurgies de notre étude, contre 16% lors de l'étude précédente. Dans notre étude, les taux globaux de RL et de SSMà 5 ans se sont améliorés comparativement aux résultats de l'étude précédente. À l'analyse multivariée, le seul facteur associé à une augmentation des RL à 5 ans a été la présence d'obstruction et les facteurs associés à une diminution de la SSM à 5 ans ont été le fort volume des interventions par des chirurgiens non spécialisés en chirurgie colorectale, la présence d'obstruction et le stade plus avancé du cancer. CONCLUSIONS: Au cours des 10 dernières années, les résultats à long terme du traitement du cancer rectal se sont améliorés. Nous avons constaté qu'une surspécialisation chirurgicale était associée à une amélioration de la SSM, mais non de la RL. L'augmentation du volume de chirurgies n'a pas eu d'incidence sur la RL ou la SSM.

Validation of colorectal cancer surgery data from administrative data sources.

BACKGROUND: Surgery is the primary treatment for colorectal cancer for both curative and palliative intent. Availability of high quality surgery data is essential for assessing many aspects of the quality of colorectal cancer care. The objective of this study was to determine the quality of different administrative data sources in identifying surgery for colorectal cancer with respect to completeness and accuracy. METHODS: All residents in Alberta, Canada who were diagnosed with invasive colorectal cancer in years 2000-2005 were identified from the Alberta Cancer Registry and included in the study. Surgery data for these patients were obtained from the Cancer Registry (which collects the date of surgery for which the primary tumor was removed) and compared to surgery data obtained from two different administrative data sources: Physician Billing and Hospital Inpatient data. Sensitivity, specificity, positive predictive value, negative predictive value and observed agreement were calculated compared to the Cancer Registry data. RESULTS: The Physician Billing data alone or combined with Hospital Inpatient data demonstrated equally high sensitivity (97% for both) and observed agreement with the Cancer Registry data (93% for both) for identifying surgeries. The Hospital Inpatient data, however, had the highest specificity (80%). The positive predictive value varied by disease stage and across data sources for stage IV (99% for stages I-III and 83-89% for stage IV), the specificity is better for colon cancer surgeries (72-85%) than for rectal cancer surgeries (60-73%); validation measures did not vary over time. CONCLUSION: Physician Billing data identify the colorectal cancer surgery more completely than Hospital Inpatient data although both sources have a high level of completeness.