Feasibility of differentiating T3 from T4a gastric cancer in different Lauren classification by determining serosa invasion: Diagnostic performance of high enhanced serosa sign

Gastric adenocarcinoma: A review of the TNM classification system and ways of spreading

Gastric cancer is the fifth most common cancer in the world. The most common histologic subtype is adenocarcinoma. Gastric adenocarcinomas are staged using the American Joint Committee on Cancer's 8th TNM classification. The perigastric ligaments, mesentery, omentum, and potential spaces between the parietal and visceral peritoneal linings play are important structures for staging. The spread of disease is influenced by the location of the tumor within the stomach, as well as by the anatomy related to the ligaments and lymph vessels. CT is the imaging modality of choice for the preoperative clinical staging of gastric cancer, and it is essential for planning treatment. To be able to do an adequate imaging workup, radiologists need to know the different pathways through which gastric cancer can spread: lymphatic, subperitoneal, direct invasion, transperitoneal, hematogenous, and extramural venous invasion.

Effect of visceral adipose tissue on the accuracy of preoperative T-staging of gastric cancer

BACKGROUND

Due to the anatomical characteristics of the tumor and the specific variables of the patients, the accuracy of preoperative T-staging of gastric cancer needs to be further improved. This study investigated the effect of visceral adipose tissue (VAT) on the accuracy of clinical T-staging of gastric cancer.

METHODS

The clinical data of 455 patients who underwent gastrectomy from January 2013 to December 2018 were analyzed retrospectively. Taking the postoperative pathological results as the reference standard, the patients were divided into accurate staging group and mistaken staging group according to the comparison of clinical T stage (cT) and pathological T stage (pT). The individual characteristics of the two groups were compared, including visceral fat content at L2/L3 level calculated on computed tomography, age, sex, tumor size, tumor location (cardia, stomach body, stomach antrum), and degree of differentiation. Multivariate logistic regression was used to determine the independent factors affecting the accuracy of cT staging.

RESULTS

Among the 455 patients, 355 patients (78.0 %) had accurate preoperative cT staging and 100 patients (22.0 %) had inaccurate preoperative cT staging. The average area of VAT in the accurate staging group was (129.8 ± 72.6) cm² and that in the mistaken staging group was (74.6 ± 61.6) cm² (P < 0.001). The optimal cut-off value of VAT was 97.8 cm² calculated according to the Yoden index. Multivariate logistic regression analysis showed that VAT, tumor location and tumor size were independent predictors of cT accuracy.

CONCLUSIONS

Patients with lower visceral fat content (<97.8 cm²) based on L2/L3 level had a higher risk of false staging in preoperative clinical T staging.

Usefulness of histologic differences and perivascular infiltration for preoperative T staging of advanced gastric cancer using computed tomography

PURPOSE

This study aimed to determine whether histologic differences and perivascular infiltration are useful for clinical T staging of advanced gastric cancer (AGC).

MATERIALS AND METHODS

This retrospective study included 160 patients with pathologically confirmed AGC who had available preoperative stomach computed tomography (CT). Using stomach CT, they were classified according to standard T stage, histologic T stage, and perivascular T stage. Accuracy of each T stage criteria was analyzed. Perivascular infiltrations for the evaluation of prognosis were correlated with time to tumor progression by log-rank test.

RESULTS

There was a significant difference between the accuracies of the standard and histologic T stages (p < 0.001), whereas there was no significant difference between the standard and perivascular T stages (p = 0.07). In 121 patients who were pathologically confirmed as having T3 or T4a tumor, there was a significant difference between the standard and perivascular T stage (p < 0.001). In patients having T3 or T4a tumor, time to tumor progression of the negative perivascular infiltration subgroup was significantly longer than the positive subgroup.

CONCLUSION

Consideration of histologic differences and perivascular infiltration may be useful for clinical T staging of AGC.