Distribution of the deepest penetrating point of minute submucosal gastric cancer

Risk factors for submucosal and lymphovascular invasion in gastric cancer looking indicative for endoscopic submucosal dissection

BACKGROUND

Submucosal and lymphovascular (SM/LV) invasions of early gastric cancer (EGC) are difficult to diagnose accurately prior to endoscopic submucosal dissection (ESD), and are occasionally found in resected specimens, requiring additional gastrectomy and lymph node dissection. We performed a retrospective study to determine the risk factors for SM/LV invasions.

METHODS

We analyzed clinicopathological data (age, sex, cancer location, gross morphology, multifocality, tumor size, histological differentiation, depth of invasion, and the presence or absence of lymphovascular invasion) in patients receiving ESD between 2007 and 2012 and presenting with EGC of 2.0 cm or smaller in size, a differentiated-type adenocarcinoma, and without ulceration.

RESULTS

Of 208 lesions consecutively resected by ESD, 143 lesions in 132 patients were included in this study. Submucosal and lymphovascular invasions were detected in 16 lesions. Multivariate analysis revealed three independent risk factors for SM/LV invasions: dominant histology of moderately-differentiated or papillary adenocarcinoma, gross type of 0-IIa + IIc or IIc + IIa, and tumor size of ≥1.5 cm. Lesions exhibiting more than two of these three risk factors were associated with having a 47 % increased incidence of SM/LV invasion (odds ratio 15; 95 % confidence interval 4.6-49.0; P < 0.0001).

CONCLUSIONS

Moderately-differentiated or papillary adenocarcinoma, 0-IIa + IIc or IIc + IIa, and a tumor size of ≥1.5 cm were identified as independent risk factors for SM/LV invasion among EGCs which appeared to be an endoscopically good indication for ESD. Careful surveillances including endoscopic ultrasonography or enhanced computed tomography might be needed for high risk patients before ESD.

Endoscopic resection of early gastric cancer

The purpose of this review is to examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer (EGC). Endoscopic mucosal resection (EMR) of EGC, with negligible risk of lymph node metastasis, is a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. EMR is a minimally invasive technique which is safe, convenient, and efficacious; however, it is insufficient when treating larger lesions. The evidence suggests that difficulties with the correct assessment of depth of tumor invasion lead to an increase in local recurrence with standard EMR when lesions are larger than 15 mm. A major factor contributing to this increase in local recurrence relates to lesions being excised piecemeal due to the technical limitations of standard EMR. A new development in endoscopic techniques is to dissect directly along the submucosal layer -- a procedure called endoscopic submucosal dissection (ESD). This allows the en-bloc resection of larger lesions. ESD is not necessarily limited by lesion size and it is predicted to replace conventional surgery in dealing with certain stages of ECG. However, it still has a higher complication rate when compared to standard EMR, and it requires high levels of endoscopic skill and experience. Endoscopic techniques, indications, pathological assessment, and methods of endoscopic resection of EGC need to be established for carrying out appropriate treatment and for the collation of long-term outcome data.

Endoscopic resection of early gastric cancer

The purpose of this review is to examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer (EGC). Endoscopic mucosal resection (EMR) of EGC, with negligible risk of lymph node metastasis, is a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. EMR is a minimally invasive technique which is safe, convenient, and efficacious; however, it is insufficient when treating larger lesions. The evidence suggests that difficulties with the correct assessment of depth of tumor invasion lead to an increase in local recurrence with standard EMR when lesions are larger than 15 mm. A major factor contributing to this increase in local recurrence relates to lesions being excised piecemeal due to the technical limitations of standard EMR. A new development in endoscopic techniques is to dissect directly along the submucosal layer -- a procedure called endoscopic submucosal dissection (ESD). This allows the en-bloc resection of larger lesions. ESD is not necessarily limited by lesion size and it is predicted to replace conventional surgery in dealing with certain stages of ECG. However, it still has a higher complication rate when compared to standard EMR, and it requires high levels of endoscopic skill and experience. Endoscopic techniques, indications, pathological assessment, and methods of endoscopic resection of EGC need to be established for carrying out appropriate treatment and for the collation of long-term outcome data.