The Clinical And Pathology Research Of Sentinel Lymph Node Biopsy In Gastric Cancer

PartⅠ The clinical feasibility and clinical value of the sentinellymph node biopsy during operation in gastric cancerObjective:To explore the clinical feasibility and clinical value of the sentinel lymph node biopsy with 1% methylence blue during operation in gastric cancer.Methods: SLNB was implemented with 1% methylence blue injected into subserosa during operation on 62 patients with gastric adenocarcinoma and the clinical feasibility and clinical value of SLN was accordingly studied. The dissected stomaches and all LNs were checked by means of routine Hematoxylin-Eosin staining(HE) to determine the depth of the tumor invasion and LNs metastases.Results: 1、Of 62 patients, 108 SLNs were found in 56 patients. There were zero to 5SLNs of one patient and 1.93±0.46 per patient, success rate was 90.3%. SLNs in 52 cases belonged to N1 nodal station.“Skip metastases” were found in 4 cases, SLNs in 2 cases belonged to N2 nodal station only, SLNs in 2 cases belonged to N1 and N2 nodal station simultaneously, among therm T1、T2 and T3 stage gastric cancer were revealed in 1、1and 2 cases, respectively.2、Totally found 766 lymph nodes in 62 patients, there were 3 to 24 LNs of one patient and 11.48 ± 0.65 per patient. With HE staining metastases were found in 162LNs(47of 62cases),among 162 LNs there were 55 SLNs. SLN metastasis degree was50.9%(55/108) and N-SLN metastasis degree was 16.2%(107/658), metastasis degree of SLN was significant higher than that of the N-SLN( χ 2=66.8493,P=0.000,P<0.005).Among 56 cases, 36 patients were found to have lymph node metastases in SLNs or non-SLNs,8 in both SLNs and N-SLNs,28 in SLNs alone. Among other 20 cases without SLN metastasis, there were five cases of N-SLN metastases,1 of T2 and 4 of T3 in these five cases of gastric cancer patients. 6 cases were not detected with SLN, amongtherm T2 and T3 stage gastric cancer were revealed in 2 and 4 cases, respectively.However,the 6 cases were found N-SLN metastasis phenomenon checked by means of routine HE.3、With HE staining metastases were found in 55 of 108 SLNs(36 of 56 cases). SLN metastasis degree was 50.9%(55/1108) and SLN metastasis rate was 64.3%(36/56),respectively. The diagnostic accuracy of the SLN status in diagnosis of the lymph node status of the patients was 91.1%(51/56). Specificity, sensitivity and false negative rate were100.0%(15/15), 87.8%(36/41)and 12.2%(5/41), respectively. The diagnostic accuracy,sensitivity and false negative rate between T1、T2 and T3 gastric cancer were statistically significant(P<0.05).This indicated that with increasing depth of invasion, the lower sensitivity and accuracy and higher false negative rate was observed.Conclusions: 1、Methylene blue could be used to locate SLN with high accuracy in patients with gastric cancer that it was a feasible technology. 2、In some cases, SLNB during opreation in gatric cancer could detect SLN“skip metastases”. 3、In the patients with gastric cancer of T1 and T2 stage, SLN could much more accurately predict the LN status, which meaned that it was much more feasibly to apply SLNB to T1 and T2 stage, at the same time should try to avoid the occurrence of false negative.Part II The clinical studies of the distribution region anddistribution rule of sentinel lymph nodes in gastric cancerObjective: By exploring the region and rule of sentinel lymph node distribution in gastric cancer, analysis of the SLNB technique could provide theoretical and practical operation of intraoperative lymph node dissection for gastric technical support.Methods: SLNB was implemented with 1% methylence blue injected into subserosa during operation on sixty two patients with gastric adenocarcinoma. Then drawed SLN distribution chart, analyzed the region and rule of sentinel lymph node distribution in gastric cancer.Results: Of 62 patients, 108 SLNs were found in 56 patients. SLNs in 52 cases belonged to N1 nodal station.“Skip metastases” were found in 4 cases, SLNs in 2 cases belonged to N2 nodal station only, SLNs in 2 cases belonged to N1 and N2 nodal stationsimultaneously. One case with Upper area cancer SLN located in NO.1 and NO.8; One case with Middle area cancer SLN located in NO.1 and NO.7;One case with Middle area cancer SLN located in NO.1 alone; One case with Low area cancer SLN located in NO.7alone. NO.7 and NO.8 were the most common sites of skip metastases. NO.1 and NO.3were the most common SLN sites of Upper area cancer, NO.3 and NO.4 were the most common SLN sites of Middle area cancer, NO.3 and NO.6 were the most common SLN sites of Low area cancer.Conclusions: From the the SLN distribution chart could draw the conclousion : SLN most located near the cancer lesions, rarely away from the lesions and the incidence of SLN skip metastases was very low. NO.7 and NO.8 were the most common sites of skip metastases.PartⅢ The detection of micrometastasis in the SLN of gastriccancer and its association with patients’ prognosisObjective: To detect the micrometastasis in the SLN of gastric cancer, appraised the value of detection methods and analyzed its association with patients’ prognosis.Methods: SLNs were detected by means of IHC staining with AE1/AE3 and FCM to explore the feature of LNs metastases and SLNs micrometastases.All the patients were followed-up, comparison of survival rate was analyzed with Log-rank test.Results: When SLN was checked by means of IHC, there were 70 SLNs and 46 patients in which AE1/AE3 was positively expressed in SLN. While SLN was checked by means of FCM, there were 73 SLNs and 48 patients in which AE1/AE3 was positively expressed in SLN. And at the same time IHC-positive SLNs were positively by flow cytometry, so there were 22 negative SLNs(in 18 of 56 cases) with HE staining showed micrometastases with IHC staining and FCM. The differences between SLN metastasis degree and SLN metastasis rate were significantly with the three different examinations(P< 0.05). The clinicopathological staging of 6 cases lead to change, three patients from stageⅠto stageⅡ, two cases increased from stage Ⅱ to stageⅢ, one cases increased from stage Ⅲ to stage Ⅳ. Making clinicopathological staging of gastric cancer became more accurate and better able to determine the condition, treatment and prognosis.Amongpathologic characters, diameter and infiltrating depth were closely associated with SLN micrometastasis. The cumulative recurrence(metastasis) rate of patients with out SLN micrometastasis was lower than that of patients with SLN micrometastasis(P<0.05). The cumulative survival rate of patients with SLN micrometastasis was lower than that of patients without SLN micrometastasis(P<0.05).Conclusions: The method of IHC staining with AE1/AE3 and FCM could more accurately predict the metastases status of LN than HE.They could increase the veracity of clinicopathological stage in patients of gastric cancer through detection of SLNs. Diameter and infiltrating depth were closely associated with SLN micrometastasis. SLN micrometastases and prognosis were significantly correlated, micrometastasis positive patients had a higher recurrence(metastasis) probability, the corresponding increased in mortality.