Population-level: Evaluation of rectal cancer care in the Netherlands

The management of rectal cancer has improved over time and is shifting towards
a more tailored approach according to disease stage and tumor and- or patient
characteristics. These developments are supported by several randomized controlled
trials. Although the risk of confounding is minimized in a RCT setting, other biases
may limit their applicability to the care of patients in daily practice. Furthermore,
older and high risk patients may not be represented in clinical trials. Also while
evidence from RCT’s may be compelling the uptake among physicians may vary and
may therefore not be representative of daily clinical practice.
Therefore it is also important to evaluate the outcomes of new treatment
strategies or surgical techniques at the population level. This may provide evidence
of effectiveness of new treatments in the general population and may aid in
identifying gaps in care and differences among hospitals. Also the impact of new
clinical guidelines and overall guideline adherence can be assessed. This thesis aims
to evaluate the impact of recent developments in rectal cancer care at the population
level in the Netherlands.
In 2014 the colorectal cancer screening program was introduced in the Netherlands.
In chapter 2 the impact of the screening program on rectal cancer treatment in the
Netherlands was assessed. The results of a large population based study of patients
diagnosed with rectal cancer between 2013-2018 were presented.
Numerous quality improvement initiatives for colorectal cancer surgery have
focused on textbook outcome parameters. In these studies, resection rate and patients
who did not undergo surgery are not included, but these parameters might help to
evaluate the surgical care for colorectal cancer. Also previous studies have shown
that the probability of undergoing surgery is associated with hospital of diagnosis
for several gastro-intestinal cancers. In chapter 3 the results of a population based
study were presented where the differences in resection rates among hospitals in
the Netherlands for non-metastatic rectal cancer was evaluated, chapter 4 aimed to
perform a likewise analysis of hospital variation in colon cancer.
In the Netherlands, preoperative nodal stage is one of the parameters to select
patients with rectal cancer for neoadjuvant therapy. Preoperative staging usually
includes magnetic resonance imaging of the pelvis, chapter 5 aimed to investigate
the number of patients who underwent surgical resection for rectal cancer with a
preoperatively underestimated lymph node stage, and to analyze the effects of nodal
understaging on postoperative local recurrence rate.
Following several landmark trials, laparoscopic rectal resection has reached
standard clinical practice. Current literature is undecided on the advantages of
robotic rectal resection and little is known on its learning curve. In chapter 6 the first
100 robotic cases were described that were performed in an experienced laparoscopic
surgery center. An increasing number of centers have implemented a robotic surgical program for rectal cancer. While introducing a robot rectal resection program seems safe, there are no data regarding implementation on a nationwide scale. Chapter 7 aimed to
evaluate the implementation of robotic resections for rectal cancer and compare the
outcomes with standard laparoscopic resection in a nationwide cohort.