Risk factors for lymph node metastasis and prognosis in colorectal neuroendocrine tumours

Purpose The detection rate of colorectal neuroendocrine tumours (CR-NETs) is increasing, but their treatment is still controversial. Lymph node metastasis is an important reference index for the selection of treatment. The aim of our study was to investigate the factors associated with lymph node metastasis and prognosis of CR-NETs. Methods The case characteristics of patients with colorectal neuroendocrine tumours from January 2011 to December 2020 were retrospectively analysed, including age, gender, tumour size, tumour location, lymph node metastasis, pathological grade and follow-up. Results A total of 195 cases of CR-NETs were included in this study. When 15 mm was used as the cut-off value, the sensitivity, specificity and area under the curve (AUC) of lymph node metastases were 95.9%, 95.2% and 0.986, respectively. Multivariate analysis suggested that tumour size ≥ 15 mm (OR: 30.517, 95% CI: 1.250 ~ 744.996, p = 0.036) and lymphovascular invasion (OR: 42.796, 95% CI: 2.882 ~ 635.571, p = 0.006) were independent risk factors for lymph node metastasis. Age ≥ 56 (HR: 7.434, 95% CI: 1.334 ~ 41.443, p = 0.022) and distant metastasis (HR: 24.487, 95% CI: 5.357 ~ 111.940, p < 0.001) were independent prognostic factors in multivariable analyses. Conclusions When the size of a CR-NET is ≥ 15 mm, the risk of lymph node metastasis is higher, and it is recommended to choose the surgical method carefully. Tumour size and lymphovascular invasion were independent risk factors for lymph node metastasis. Age ≥ 56 and distant metastasis were independent prognostic factors.

Mesenteric occlusive disease of the inferior mesenteric artery is associated with anastomotic leak after left-sided colon and rectal cancer surgery: a retrospective cohort study

Purpose Anastomotic leak (AL) is a serious complication following colorectal surgery. Atherosclerosis causes inadequate anastomotic perfusion and is suggested to be a risk factor for AL. The aim of this study was to investigate the association of mesenteric occlusive disease on preoperative computed tomography (CT) scan with AL after left-sided colon or rectal cancer surgery. Methods This was a retrospective, multicenter cohort study including 1273 patients that underwent left-sided or rectal cancer resection between 2009 and 2018 from three hospitals in the Netherlands. AL patients were 1:1 matched with non-leak patients and preoperative contrast-enhanced CT-scans were retrospectively analyzed for mesenteric atherosclerotic lesions. The main outcome measure was the presence of mesenteric occlusive disease on the preoperative CT-scan. Results Anastomotic leak developed in 6% of 1273 patients (N = 76). Low anterior resection and stage I–III disease were statistically significant associated with AL (p = 0.01, p = 0.04). No other statistically significant differences in patient characteristics between AL and non-leak patients were found. A clinically significant stenosis (≥ 70–100%) of the inferior mesenteric artery was statistically significant more frequent present in AL patients, compared to non-leak patients (p < 0.01). No statistically significant differences in the presence of mesenteric occlusive disease of the celiac artery and superior mesenteric artery between AL patients and non-leak patients were found. Conclusion Mesenteric occlusive disease of the IMA on preoperative CT-scan is associated with AL after left-sided colon or rectal resection for cancer. Preoperative identification of high-risk patients with a preoperative CT-scan of the mesenteric vasculature might be useful to reduce the risk of AL.