– The second Dutch Snapshot study –
Rectal cancer treatment has become a multimodality approach, although surgical resection is still the cornerstone. Rectal surgery has significantly changed over the last few decades. Decisions on treatment approaches in current daily practice are mainly based on (sub-)analyses of multicentre RCTs.1, 2, 3, 4, 5 However, as the study population is often subject to strict in- and exclusion criteria, RCTs might not reflect the real life patient population. In addition, inclusion in RCTs is often from expert centers.6
1) To assess national variation in practice and outcomes in the treatment of rectal cancer;
2) To compare these results to published landmark RCTs as a benchmark.
A retrospective, resident-led, collaborative research project with a cross-sectional study design was conducted in 71 hospitals in the Netherlands. Short term data of all patients undergoing resection of colorectal cancer are prospectively collected in the Dutch Colorectal Audit (DCRA) registry. The DCRA dataset of the year 2011 was extended with additional procedural data and long term surgical and oncological outcomes through the Snapshot research design. Web-based data-collection was performed by surgical residents under supervision of a consultant surgeon during a 5 month period.
All patients who had a rectal cancer resection in 2011 were identified from the DCRA registry. In total, additional data were collected for 2102 patients out of the potential 2633 (79.8%) patients that were originally registered in 2011.
The first publication within Snapshot project demonstrated overall circumferential resection margin (CRM) involvement of 9.3% in the Snapshot versus 18.5% in the Dutch TME trial. CRM positivity after laparoscopic resection was 7.8% in the Snapshot study versus 9.5% in the COLOR II trial. Three-year overall local recurrence rate in the Snapshot was 5.9%, with a disease free survival of 67.1%, and overall survival of 79.5%. Benchmarking with the RCTs revealed an overall favourable long-term outcome of the Snapshot cohort.
This Snapshot project led to a total of 12 publications assessing late detected anastomotic leakage after low anterior resection for rectal cancer, as well as the proportion of leakages that develops into a chronic presacral sinus. Other projects included variation in the use of re-staging MRI and timing of surgery after chemoradiotherapy, the role of omentoplasty in abdominoperineal resection, impact of conversion and leakage on survival, dealing with the rectal stump during sphincter preserving surgery with end colostomy, the influence of hospital volume on long-term oncological outcome, the impact of anaemia on oncological outcome, the treatment, survival of locally recurrent rectal cancer, the effects of preoperative lymph node understaging, the oncological outcomes of restorative and nonrestorative low anterior resection and the prognostic value of lymph node count.