Predictors of lymph-node metastasis in surgically resected T1 colorectal cancer in Western populations

Abstract

Background The risk of lymph-node metastasis (LNM) in T1 colorectal cancer (CRC) has not been well documented in heterogeneous Western populations. This study investigated the predictors of LNM and the long-term outcomes of patients by analysing T1 CRC surgical specimens and patients’ demographic data. Methods Patients with surgically resected T1 CRC between 2004 and 2014 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Patients with multiple primary cancers, with neoadjuvant therapy, or without a confirmed histopathological diagnosis were excluded. Multivariate logistic-regression analysis was used to identify the predictors of LNM. Results Of the 22,319 patients, 10.6% had a positive lymph-node status based on the final pathology (nodal category: N1 9.6%, N2 1.0%). Younger age, female sex, Asian or African-American ethnicity, poor differentiation, and tumor site outside the rectum were significantly associated with LNM. Subgroup analyses for patients stratified by tumor site suggested that the rate of positive lymph-node status was the lowest in the rectum (hazard ratio: 0.74; 95% confidence interval: 0.63–0.86). Conclusion The risk of LNM was potentially lower in Caucasian patients than in API or African-American patients with surgically resected T1 CRC. Regarding the T1 CRC site, the rectum was associated with a lower risk of LNM.

Endoscopic Treatment of T1 Colorectal Cancer

“…In addition, high-grade tumor budding (defined as single cells or cell clusters at the tumor invasion front) has been established as an important independent predictor of lymph-node metastasis [21,22]. Other factors such as tumor localization in the sigmoid/rectum were found to be associated with a higher lymph-node metastasis risk [23][24][25] but conflicting results have also been reported [26]. The concept of endoscopic resection of T1CRC was confirmed in a recent meta-analysis of 71 studies including more than 5000 patients.…”

Use of artificial intelligence in the management of T1 colorectal cancer: a new tool in the arsenal or is deep learning out of its depth?

“…The histological risk factors include lymphovascular invasion, tumor budding, and histological grade in addition to the depth of invasion. [10][11][12][13][14][15] However, the risk of LNM in T1 CRC is estimated to be between 6% to 14%, [16][17][18][19] which indicates that the postoperative morbidity and mortality associated with surgery for T1 CRC is avoidable. 20,21 As such, accurately predicting the depth of invasion on the initial colonoscopy and consistent and precise histological specimen reports are crucial in patients with T1 CRC.…”