A new scientific study, authored by researchers from the Belgian Cancer Registry in collaboration with KU Leuven, shows that patients with stage I-III rectal cancer in Belgium have better survival rates when operated on in hospitals with a higher annual volume of rectal cancer surgery. This national, population-based analysis included more than 11,500 patients diagnosed with rectal cancer between 2009 and 2018.
Surgical volume as quality indicator
The study examined the association between the average annual number of rectal cancer surgeries per hospital and three outcome measures: mortality within 90 days, excess mortality within 1 year, and 5-year survival. Hospitals were divided into three categories: low (<15 surgeries/year), medium (15-29), and high (≥30).
The results show a clear association between surgical volume and outcomes:
90-day mortality was significantly lower in high-volume hospitals (2.3%) than in low-volume hospitals (3.7%).
1-year excess mortality was 2.9% in high-volume hospitals compared with 4.7% in low-volume hospitals.
5-year survival was 75.9% in high-volume hospitals, compared with 70.3% in low-volume hospitals.
An additional statistical analysis in which volume was treated as a continuous variable showed that hospitals with at least 35 interventions per year achieved better outcomes on average, indicating a threshold for optimal quality of care.
The results suggest that especially the first six months after surgery are crucial for long-term outcomes, and that factors such as postoperative care and follow-up may play a role in the volume effect.
No spontaneous centralisation observed
During the 10-year study period, rectal cancer surgeries were performed in 100 Belgian hospitals. Strikingly, 60% of the surgeries took place in low- and medium-volume hospitals, and no clear trend towards centralisation was observed over the years.
Conclusion and policy implications
The study confirms previous international findings on the importance of surgical volume, and highlights the need to reconsider the current organisation of rectal cancer care in Belgium. The authors advocate the introduction of a realistic minimum threshold for the number of annual surgeries per hospital to improve quality of care.
