Endoscopic submucosal dissection: can it safely expand indications for a minimally invasive approach to patients with early gastric cancer?

Predictive factors for lymph node metastasis and defining a subgroup treatable for laparoscopic lymph node dissection after endoscopic submucosal dissection in poorly differentiated early gastric cancer

AIM

To investigate the predictive factors of lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC); to guide the individual application of a combination of endoscopic submucosal dissection (ESD) and laparoscopic lymph node dissection (LLND) in a suitable subgroup of patients with poorly differentiated EGC.

METHODS

We retrospectively analyzed 138 patients with poorly differentiated EGC who underwent gastrectomy with lymphadenectomy between January 1990 and December 2015. The association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95% confidence interval (95%CI) were calculated. We further examined the relationship between the positive number of the significant predictive factors and the LNM rate.

RESULTS

The tumor diameter (OR = 13.438, 95%CI: 1.773-25.673, P = 0.029), lymphatic vessel involvement (LVI) (OR = 38.521, 95%CI: 1.975-68.212, P = 0.015) and depth of invasion (OR = 14.981, 95%CI: 1.617-52.844, P = 0.024) were found to be independent risk factors for LNM by multivariate analysis. For the 138 patients diagnosed with poorly differentiated EGC, 21 (15.2%) had LNM. For patients with one, two and three of the risk factors, the LNM rates were 7.7%, 47.6% and 64.3%, respectively. LNM was not found in 77 patients that did not have one or more of the three risk factors.

CONCLUSION

ESD might be sufficient treatment for intramucosal poorly differentiated EGC if the tumor is less than or equal to 2 cm in size and when LVI is absent upon postoperative histological examination. ESD with LLND may lead to the elimination of unnecessary gastrectomy in poorly differentiated EGC.

Feasibility study on expanded indication for endoscopic submucosal dissection of intramucosal poorly differentiated early gastric cancer

AIM: To identify clinicopathological factors predictive of lymph node metastasis (LNM) in intramucosal poorly differentiated early gastric cancer (EGC), and further to expand the possibility of using endoscopic submucosal dissection (ESD) for the treatment of intramucosal poorly differentiated EGC.

METHODS: Data for 81 surgically treated patients with intramucosal poorly differentiated EGC were collected, and the association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Several clinicopathologic factors were investigated to identify predictive factors for lymph nodes metastasis, including gender, age, family history of gastric cancer, number of tumors, tumor location, ulceration, tumor size, macroscopic type, lymphatic vessel involvement, and signet-ring-cell component.

RESULTS: Tumor size (OR = 7.273, 95%CI: 1.246-29.918, P = 0.042), lymphatic vessel involvement (OR = 42.219, 95%CI: 1.923-97.052, P = 0.018) and signet-ring-cell component (OR = 17.513, 95%CI: 1.647-77.469, P = 0.034) that were significantly associated with LNM by univariate analysis, were found to be significant and independent risk factors for LNM by multivariate analysis. However, gender, age, family history of gastric cancer, number, location, ulceration and macroscopic type of tumor were found not to be associated with LNM. Of these 81 patients diagnosed with intramucosal poorly differentiated EGC, 7 (8.6%) had LNM. The LNM rates were 9.1%, 22.2% and 57.1%, respectively, in cases with one, two and three of the risk factors. There was no LNM in 54 patients without the three risk clinicopathological factors.

CONCLUSION: Tumor size, lymphatic vessel involvement and signet-ring-cell component are independently associated with the presence of LNM in intramucosal poorly differentiated EGC. Thus, these three risk factors may be used as a simple criterion to expand the possibility of using ESD for the treatment of intramucosal poorly differentiated EGC.

Defining a Subgroup Treatable for Laparoscopic and Endoscopic Cooperative Surgery in Undifferentiated Early Gastric Cancer: the Role of Lymph Node Metastasis

BACKGROUND

Recently, the use of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) and the development of laparoscopic and endoscopic cooperative surgery (LECS) have enabled either the preservation of the stomach or the minimization of the extent of partial resection. ESD has recently been practiced on a differentiated type of EGC. However, there is no clear evidence for endoscopic treatments of undifferentiated EGC. The purposes of this study are to investigate predictive factors of lymph node metastasis (LNM) in undifferentiated EGC and expand the possibility of using LECS for the treatment of undifferentiated EGC.

METHODS

Data from 116 patients with undifferentiated EGC and surgically treated were collected, and the association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95 % confidence interval (95 % CI) were calculated.

RESULTS

The tumor size (OR = 11.748, 95 % CI 2.034-62.213, P = 0.008), depth of invasion (OR = 13.928, 95 % CI 1.971-92.434, P = 0.016), and lymphatic vessel involvement (OR = 11.522, 95 % CI 2.645-59.172, P = 0.021) that were significantly associated with LNM by univariate analysis were found to be significant and independent risk factors for LNM by multivariate analysis. The LNM rate was 5.9 % (4/68) and 29.2 % (14/48) with intramucosal and submucosal undifferentiated EGC, respectively. LNM was observed in 66.7 % (2/3) of patients with both risk factors (tumor larger than or equal to 2.0 cm and the presence of lymphatic vessel involvement (LVI)), but in none of 36 patients without the two risk factors in intramucosal undifferentiated EGC. The 5-year survival rates were 88.9, 72.4, and 33.3 %, respectively, in cases with none, one, and two of the risk factors, respectively, in intramucosal undifferentiated EGC (P < 0.05).

CONCLUSIONS

ESD alone may be a sufficient treatment for intramucosal undifferentiated EGC if the tumor is less than 2.0 cm in size and when LVI is absent upon postoperative histological examination. LECS is feasible and safe for patients with undifferentiated EGC.

Risk clinicopathological factors for lymph node metastasis in poorly differentiated early gastric cancer and their impact on laparoscopic wedge resection

AIM: To investigate the predictive factors of lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC), and enlarge the possibility of using laparoscopic wedge resection (LWR).

METHODS: We retrospectively analyzed 85 patients with poorly differentiated EGC who underwent surgical resection between January 1992 and December 2010. The association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95%CI were calculated. We further examined the relationship between the positive number of the three significant predictive factors and the LNM rate.

RESULTS: In the univariate analysis, tumor size (P = 0.011), depth of invasion (P = 0.007) and lymphatic vessel involvement (P < 0.001) were significantly associated with a higher rate of LNM. In the multivariate model, tumor size (OR = 7.125, 95%CI: 1.251-38.218, P = 0.041), depth of invasion (OR = 16.624, 95%CI: 1.571-82.134, P = 0.036) and lymphatic vessel involvement (OR = 39.112, 95%CI: 1.745-123.671, P = 0.011) were found to be independently risk clinicopathological factors for LNM. Of the 85 patients diagnosed with poorly differentiated EGC, 12 (14.1%) had LNM. The LNM rates were 5.7%, 42.9% and 57.1%, respectively in cases with one, two and three of the risk factors respectively in poorly differentiated EGC. There was no LNM in 29 patients without the three risk clinicopathological factors.

CONCLUSION: LWR alone may be sufficient treatment for intramucosal poorly differentiated EGC if the tumor is less than or equal to 2.0 cm in size, and when lymphatic vessel involvement is absent at postoperative histological examination.