A nomogram for predicting lymph node metastasis in early gastric cancer / 中华胃肠外科杂志

Objective: To explore the independent risk factors of lymph node metastasis (LNM) in early gastric cancer, and to use nomogram to construct a prediction model for above LNM. Methods: A retrospective cohort study was conducted. Inclusion criteria: (1) primary early gastric cancer as stage pT1 confirmed by postoperative pathology; (2) complete clinicopathological data. Exclusion criteria: (1) patients with advanced gastric cancer, stump gastric cancer or history of gastrectomy; (2) early gastric cancer patients confirmed by pathology after neoadjuvant chemotherapy; (3) other types of gastric tumors, such as lymphoma, neuroendocrine tumor, stromal tumor, etc.; (4) primary tumors of other organs with gastric metastasis. According to the above criteria, 1633 patients with early gastric cancer who underwent radical gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital First Medical Center from December 2005 to December 2020 were enrolled as training set, meanwhile 239 patients with early gastric cancer who underwent gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital Fourth Medical Center from December 2015 to December 2020 were enrolled as external validation set. Risk factors of LNM in early gastric cancer were identified by using univariate and multivariate logistic regression analyses. A nomogram prediction model was established with significant factors screened by multivariate analysis. Area under the receiver operating characteristic curve (AUC) was used for assessing the predictive value of the model. Calibration curve was drawn for external validation. Results: Among 1633 patients in training set, the mean number of retrieved lymph nodes was 20 (13-28), and 209 patients (12.8%) had lymph node metastasis. Univariate analysis showed that gender, resection range, tumor location, tumor morphology, lymph node clearance, vascular invasion, lymphatic cancer thrombus, tumor length, tumor differentiation, microscopic presence of signet ring cells and depth of tumor invasion were associated with LNM (all P<0.05). Multivariate analysis revealed that females, tumor morphology as ulcer type, vascular invasion, lymphatic cancer thrombus, tumor length≥3 cm, deeper invasion of mucosa, and poor differentiation were independent risk factors for LNM in early gastric cancers (all P<0.05). Receiver operating characteristic curve indicated that AUC of training set was 0.818 (95%CI: 0.790-0.847) and AUC of external validation set was 0.765 (95%CI: 0.688-0.843). The calibration curve showed that the LNM probability predicted by nomogram was consistent with the actual situation (C-index: 0.818 in training set and 0.765 in external validation set). Conclusions: Females, tumor morphology as ulcer type, vascular invasion, lymphatic cancer thrombus, tumor length≥3 cm, deeper invasion of mucosa and poor differentiation are independent risk factors for LNM of early gastric cancer. The establishment of a nomogram prediction model for LNM in early gastric cancer has great diagnostic value and can provide reference for treatment selection.

Analysis of influence factors for short-term recurrence of retroperitoneal liposarcoma after complete resection / 中华外科杂志

Objective: To examine the influence factors of short-term recurrence after complete surgical resection of retroperitoneal liposarcoma. Methods: The clinicopathological data of retroperitoneal liposarcoma at Department of General Surgery, the First Medical Center, People's Liberation Army General Hospital from January 2000 to January 2020 were retrospectively analyzed. There were 60 males and 31 females, aged (52.1±9.9) years (range: 30 to 84 years). Tumor recurrence within 12 months after complete resection was defined as short-term recurrence, and tumor recurrence more than 12 months was defined as non-short-term recurrence. The t test, rank-sum test, χ2 test and Fisher exact test were conducted for inter-group comparison. Logistic regression analysis was used to analyze the independent influence factors for the short-term recurrence of retroperitoneal liposarcoma after complete resection. The Kaplan-Meier curve was used to calculate the recurrence-free survival, and the Log-rank test was adopted for the comparison between the groups. Results: The univariate analysis results showed that irregular tumor morphology, multiple pathological subtypes, pathological scores>3, and multiple primary tumors are influence factors for short-term recurrence after complete resection of retroperitoneal liposarcoma (χ2: 4.422 to 7.773, all P<0.05). Regression analysis of the above risk factors showed that multiple primary tumors was the independent risk factor (OR=2.918, 95%CI: 1.127 to 7.556, P=0.027). In the short-term recurrence group, Kaplan-Meier curve analysis showed that patients with multiple primary tumors had a shorter median recurrence time than patients with unifocal tumor (6 months vs. 9 months, P=0.028). Conclusions: Multiple primary tumor is an independent risk factor for short-term recurrence after complete resection of retroperitoneal liposarcoma. It suggests that the frequency of follow-up after surgery should be increased for such patients.