Auxiliary diagnosis of lymph node metastasis in early gastric cancer using quantitative evaluation of sentinel node radioactivity

Abstract

Background Sentinel node (SN) mapping using dye and radioisotope (RI) tracer has been reported to be feasible in cases of early gastric cancer. Because accurate diagnosis of micrometastasis is sometimes difficult in the limited time available during surgery, a faster and simpler method of improving the intraoperative diagnostic precision of lymph node metastasis is needed. The amount of tracer deposited in an SN can be determined from its radioactivity; however, the significance of the RI count has not been fully discussed. We investigated the clinical impact of the RI count when used as an adjunct to conventional lymph node dissection when diagnosing lymphatic metastasis in cases of early gastric cancer. Methods From 2008 to 2009, patients with clinically diagnosed T1N0M0 gastric cancers who underwent gastrectomy and SN mapping were enrolled. SNs were examined by intraoperative and postoperative pathology. The RI count was measured for each SN with a handheld gamma probe; the correlation between nodal metastasis and the RI count was assessed. Results A total of 308 SNs were harvested from 72 patients. Patients with SN metastasis had significantly higher total RI counts than those without SN metastasis (p = 0.007). Among cases with SN metastasis, RI counts were also significantly elevated in metastasis-positive nodes, stations, and basins. In these cases, the most of SNs having the highest RI count in each case had metastasis including isolated tumor cells. Conclusion In early gastric cancer patients, a high RI count from an SN was correlated with lymph node metastasis. Therefore, RI counting may aid efficient pathological diagnosis and focused lymph node dissection.

Risk factors for lymph node metastasis in non-sentinel node basins in early gastric cancer: sentinel node concept

“…Our previous study demonstrated that the number of identified SNs in metastatic cases was significantly higher than that in non-metastatic cases. We believe that the development of the lymphatic network and a large lymphatic flow rate may affect the number of identified SNs and may be associated with metastasis in non-SN basins [38]. Although no significant difference with respect to OS were observed, CSS was significantly low in patients with LN metastasis in non-SN basins.…”

Risk factors of lymph node metastasis in 734 early gastric carcinoma radical resections in a Chinese population

“…Continuous variables were expressed as mean ± standard deviation, whereas categorical variables were expressed as numbers and percentages. Differences among categorical variables between risk factors and LNM were assessed using the χ test, the Fisher's exact test, or the Kruskal–Wallis H test, when appropriate, while those among continuous variables were evaluated using the one‐way anova. Univariate and multivariate logistic regression analyses were utilized to identify independent risk factors of LNM in EGC.…”

“…For those at a high risk of LNM, however, a radical gastrectomy with nodal dissection is required. Therefore, an accurate prediction of the risk of LNM in EGC is very important for clinical therapy decision‐making process and also for the patient's prognosis . Unfortunately, the risk of LNM in EGC remains elusive, even after clinical investigations with a combination of upper endoscopy, endoscopic ultrasonography (EUS) and computed tomography (CT).…”

Effect of World Health Organization (WHO) Histological Classification on Predicting Lymph Node Metastasis and Recurrence in Early Gastric Cancer

“…Patients with EGC generally have an excellent prognosis after curative resection; the 5-year survival rate is reported to be around 90% [ 1 – 3 ]. It is well known that LNM in EGC is associated with prognosis [ 4 – 7 ], and predicting LNM preoperatively is very important for minimal treatment. However, it is still very difficult to precisely diagnose N-stage in EGC, even when endoscopic ultrasonography (EUS) and computed tomography (CT) are used.…”