Lymph node status is of major prognostic importance in non-metastatic rectal cancer. For oncological reasons, central arterial ligation of the inferior mesenteric artery (IMA) is suggested. However, there is no conclusive evidence presented for this procedure.

This study aimed at investigating the localisation of lymph node metastases and the role of central versus peripheral arterial ligation of in rectal cancer specimens.

Prospective population-based study of specimens from patients that underwent surgical resection for rectal cancer in Västmanland County, Sweden. Specimens were divided in 3 sections (A-C) and the total amount of lymph nodes and the location of lymph node metastases were analysed.

Multivariate analysis was used to explore the relationship between lymph node counts and age, gender, BMI, preoperative oncological treatment, type of surgery, tumour stage, vessel and specimen length.

Inclusion Criteria:

• All patients that were curatively operated for rectal cancer in Västmanlands county 2012-2016.

Exclusion Criteria:

• Patients that were not operated or had another type of cancer.

All patients that were diagnosed with rectal cancer 2012-2016 in Västmanlands county.