Prediction model for lymph node metastasis in superficial colorectal cancer: a better choice than computed tomography.

BACKGROUND: Risk evaluation of lymph node metastasis (LNM) in superficial colorectal cancer resected by endoscopic surgery is critical for determining subsequent therapeutic strategies, but the role of existing clinical methods, including computed tomography, remains limited. METHODS: Features of the nomogram were determined by logistic regression analysis, and the performance was validated by calibration plots, ROC curves and DCA curves in both the training set and the validation set. RESULTS: A total of 608 consecutive superficial CRC cases were randomly divided into 426 training and 182 validation cases. Univariate and multivariate logistic regression analyses revealed that age < 50, tumour budding, lymphatic invasion and lower HDL levels were risk factors for LNM. Stepwise regression and the Hosmer‒Lemeshow goodness of fit test showed that the nomogram had good performance and discrimination, which was validated by ROC curves and calibration plots. Internal and external validation demonstrated that the nomogram had a higher C-index (training group, 0.749, validation group, 0.693). DCA and clinical impact curves graphically show that the use of the nomogram to predict LNM had remarkable predictive power. Finally, in comparison with CT diagnosis, the nomogram also visually showed higher superiority, as demonstrated by ROC, DCA and clinical impact curves. CONCLUSION: Using common clinicopathologic factors, a noninvasive nomogram for individualized prediction of LNM after endoscopic surgery was conveniently established. Nomograms have great superiority in the risk stratification of LNM compared with traditional CT imaging.

Inverse Association of Age with Risk of Lymph Node Metastasis in Superficial Colorectal Cancer: A Large Population-Based Study.

BACKGROUND: Superficial colorectal cancer (SCRC) is defined as colorectal cancer (CRC) confined to the mucosa or submucosa. Endoscopic resection (ER) is widely used to resect differentiated SCRC from patients without lymph node metastasis (LNM). However, it is unclear whether ER is suitable for use with patients with differentiated early-onset SCRC because early-onset CRC is more aggressive. Therefore, we aimed to investigate the association between age of CRC onset and LNM. MATERIALS AND METHODS: We retrieved data for patients with surgically resected differentiated-type SCRCs from the Surveillance, Epidemiology, and End Results (SEER) database. Rate of LNM was compared among patients aged 18-39, 40-49, 50-59, 60-69, and ≥70 years. The association between age and LNM was further examined using multivariate logistic regression. RESULTS: We retrieved 34,506 records of differentiated SCRCs from the SEER database, including 667 patients aged 18-39 years, 2,385 aged 40-49, 8,075 aged 50-59 years, 9,577 aged 60-69 years, and 13,802 aged ≥70 years. Rates of LNM were 15.74%, 14.13%, 10.67%, 8.07%, and 6.76% for patients aged 18-39, 40-49, 50-59, 60-69, and ≥70 years, respectively. We found an inverse correlation between age at diagnosis and risk of LNM from the univariate analysis (p < .001). Compared with patients aged 18-39, the odds ratios with 95% confidence interval (CI) for patients aged 40-49, 50-59, 60-69, and ≥70 years were 0.90 (0.71-1.15, p = .376), 0.69 (0.56-0.87, p = .001), 0.54 (0.43-0.68, p < .001), and 0.47 (0.38-0.60, p < .001), respectively. CONCLUSION: In differentiated SCRCs, younger age at diagnosis was associated with higher risk of LNM. IMPLICATIONS FOR PRACTICE: Endoscopic resection (ER) is widely used to resect differentiated superficial colorectal cancer (SCRC) without lymph node metastasis (LNM). However, no study has ever investigated risk of LNM of early-onset SCRC compared with average onset SCRC to explore whether ER is suitable for early-onset SCRC. To the authors' knowledge, this population-based study is the first study to find inverse correlation between age at diagnosis and risk of LNM in differentiated SCRCs. This finding indicates that ER may not be suitable for young patients with differentiated SCRC. Because the 30-day operative mortality after surgery is higher but the risk of LNM is lower in older patients compared with younger patients, ER for differentiated SCRCs may be advantageous over surgery for older patients.

Current status of endoscopic submucosal tunnel dissection for treatment of superficial gastrointestinal neoplastic lesions.

INTRODUCTION: With the widespread application of screening endoscopy and development of endoscopy-related instruments, more and more gastrointestinal cancers are detected in an early stage. Endoscopic resection is a preferred method for selected patients with superficial gastrointestinal neoplastic lesions, and endoscopic submucosal dissection (ESD) has become a standard method for its ability to perform en bloc resection regardless of the lesion size. ESD can be performed in a conventional or tunneling way, and the latter is termed endoscopic submucosal tunnel dissection (ESTD). AREA COVERED: In the present review, we provided a comprehensive review on ESTD for treatment of superficial gastrointestinal neoplastic lesions. We mainly focus on technical details, safety and efficacy of ESTD for esophageal, gastric and colorectal lesions. The present review is expected to provide tips for operators who are going to perform ESTD. EXPERT OPINION: The best indication of ESTD is large superficial esophageal neoplastic lesions (circumferential extent > 1/3 and longitudinal extent > 3 cm). Although ESTD has shown promising primary results for superficial gastric and colorectal neoplastic lesions, it is technically difficult and should be attempted only in experienced hands. Post-treatment stricture is a major concern, and preventive measures are recommended for patients with high risk of post-ESTD stricture.

p53 Overexpression and K-ras Codon 12 Mutations in Submucosal Invasive Colorectal Cancer.

We examined histological findings, p53 overexpression and K-ras codon 12 mutations and the histology of submucosal invasive (sm) colorectal cancers. Sixty specimens of sporadic sm cancer were obtained by surgical resection or endoscopic polypectomy. p53 expression was examined by im-munohistochemical staining using the streptavidin-biotin method. K-ras codon 12 mutations were detected by polymerase chain reaction (PCR) and dot blot hybridization. These tumors were classified as horizontal or nonhorizontal growth sm cancers. Fifteen of 60 (25%) superficial type horizontal growth cancers gave rise to sm cancers. There was no significant difference in size between horizontal and nonhorizontal growth sm cancers. There was no significant difference in the frequency of p53 expression between horizontal [8/15 (53.3%)] and nonhorizontal [22/45 (48.9%)] growth sm cancers. The frequency of K-ras codon 12 point mutations was significantly lower in horizontal growth [0/15 (0%)] sm cancers as compared to nonhorizontal growth [22/45 (48.9%)] sm cancers. We conclude that the development of superficial type horizontal growth cancers may involve a distinct genetic pathway.