The treatment of rectal cancer is developing rapidly in the Netherlands, as well as internationally. This is accompanied by an increase in complexity of diagnosis and treatment, particularly when the tumor is located closer to the anorectal junction. Within these developments there is an important role for quality evaluation, where continuous feedback is able to improve care for rectal cancer in the Netherlands. By supplementing data from the Dutch ColoRectal Audit (DCRA) with additional data concerning diagnostics and treatment of rectal cancer patients operated in the year 2016, the Snapshot Rectumcarcinoom 2016 aimed to assess the improvement in surgical and oncological outcomes.

Multiple changes in the treatment pathway for rectal cancer patients have contributed to the rapid developments over the last decade. First of all, in 2014 there has been revision of the guidelines, which adjusted MRI assessment and changed indications for neoadjuvant treatment. Moreover, the start of population screening has led to earlier detection of rectal cancer, which has increased attention for organ-sparing treatment. Furthermore, there has been a shift in surgical treatment towards more minimally invasive surgery and new techniques including robotic surgery and TaTME have been introduced. The centralization of care for rectal cancer patients has led to a decrease in number of hospitals that provide this care. These changes together ask for quality evaluation to provide feedback for further improvement of rectal cancer care in the Netherlands.

The Snapshot Rectumcarcinoom has been conducted retrospectively in 2021 concerning the patients operated in 2016 with a 4 year follow up. A similar snapshot study to evaluate outcomes of patients with rectal cancer who were operated in 2011 has been conducted retrospectively in 2015. This enables the Snapshot Rectumcarcinoom 2016 study to compare the oncological and surgical outcomes between 2011 and 2016.

Moreover, this study aimed to evaluate the practices and treatment of patients rectal cancer and enlarged lateral lymph nodes in 2016. Since the implementation of TME surgery there has been a shift toward more lateral recurrences, most likely caused by inadequate treatment of lateral lymph nodes. An international guideline for the appropriate treatment has been lacking, causing substantial variation practices. For example, lateral lymph nodes are often not mentioned by radiologists or during multidisciplinary meetings and there is no clear consensus concerning delineation of radiotherapy in lateral nodes. Moreover, in contrast to Asian countries, in the Netherlands surgical resection of the lateral lymphatic tissue is almost never done as clinicians have always relied on neoadjuvant treatment to sterilize the lateral compartment. Nevertheless, the Consortium study found that 16% of the population of rectal cancer patients had enlarged lateral lymph nodes, leading to a 19.5% 5-year lateral recurrence rate. When these nodes were removed by lateral lymph node dissection (LLND), this recurrence percentage was reduced to 5.7%. The Snapshot study aimed assess the current heterogeneity in diagnostics and treatment of lateral lymph nodes and increase awareness by training of the different specialties.

Inclusion Criteria:

• Primary rectal cancer
• Operated in 2016 in a Dutch hospital
• Registred in the DCRA-register

Exclusion Criteria:

• Wait and see
• Resection for regrowth after wait and see

All patients who underwent resection for primary rectal cancer in the Netherlands in 2016.

IPD data that underlie results in a publication can be made available upon reasonable request

Starting after initial publication of data

Requests will be assessed by the study team