Intragastric Mucosal Resection Research Articles

Minimally Invasive Surgery for Gastric Cancer: The Future Standard of Care

Laparoscopy-assisted distal gastrectomy for gastric cancer was first reported by Kitano et al. in 1991. Laparoscopic wedge resection (LWR) and intragastric mucosal resection (IGMR) were quickly adapted for gastric cancer limited to the mucosal layer and having no risk of lymph node metastasis. Following improvements in endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), the use of LWR and IGMR for these indications decreased, and patients with gastric cancer, including those with a risk of lymph node metastases, were more likely to be managed with laparoscopic gastrectomy (LG) with lymph node dissection. Many retrospective comparative trials and randomized-controlled trials (RCT) have confirmed that LG is safe and feasible, and that short-term outcomes are better than those of open gastrectomy (OG) in patients with early gastric cancer (EGC). However, these trials did not include a satisfactory number of patients to establish clinical evidence. Thus, additional multicenter randomized-controlled trials are needed to delineate significantly quantifiable differences between LG and OG. As laparoscopic experience has accumulated, the indications for LG have been broadened to include older and overweight patients and those with advanced gastric cancer. Moreover, advanced techniques, such as laparoscopy-assisted total gastrectomy, laparoscopy-assisted proximal gastrectomy, laparoscopy-assisted pylorus-preserving gastrectomy (PPG), and extended lymph node dissection (D2) have been widely performed.In the near future, sentinel node navigation and robotic surgery will become additional options in minimally invasive surgery (MIS) involving LG. Such developments will improve the quality of life of patients following gastric cancer surgery.

Minimally invasive surgery for gastric cancer — toward a confluence of two major streams: a review

The minimalization of therapeutic invasiveness in order to preserve quality of life (QOL) is a major topic in the management of early gastric cancer. After laparoscopic surgery for gastric cancer was introduced by Kitano et al. in 1991, an enthusiasm to develop laparoscopic procedures has grown steadily. In the initial phase, early gastric cancer limited to the mucosal layer with no risk of lymph node metastasis was treated by laparoscopic wedge resection or intragastric mucosal resection. Since technical and instrumental advances in endoscopic treatment were achieved by gastroenterologists, these cases can be managed by intraluminal endoscopic approaches. The attention of surgeons then shifted to more radical procedures such as laparoscopic gastrectomy with lymph node dissection, which is comparable to open surgery and can be indicated even in advanced cancer. Although this paradigm shift has already been realized in the field of colorectal surgery, we must pay attention to the particular biological nature of gastric cancer in terms of the potential of peritoneal dissemination. While early-phase recovery after surgery has been improved by laparoscopic surgery, preservation of late-phase QOL by function-preserving surgery is also essential in this regard; therefore, the sentinel node (SN) concept has been a much-discussed topic in gastric cancer surgery to approach this aspect. Recently, the validity of the SN concept has been demonstrated by a number of single institutional studies, and prospective multicenter trials are currently ongoing. Theoretically, various types of function-preserving surgery could be applied in cases of early gastric cancer with negative SNs as less invasive surgery to improve long-term QOL. Although we still have to solve several remaining issues in the treatment of gastric cancers, a confluence of these two major streams, laparoscopic surgery and sentinel node navigation surgery, would enable us to apply a novel individualized minimally invasive approach, both in terms of degree of incisional access and extent of function preservation.

Current status of laparoscopic gastrectomy for cancer in Japan.

Because of the increased incidence of early gastric cancer in Japan, minimally invasive laparoscopic approaches to gastric malignancies have been under development since 1991. Laparoscopic local resection of the stomach, i.e., laparoscopic wedge resection (LWR) and intragastric mucosal resection (IGMR), is used to treat mucosal cancer without lymph node metastasis. Laparoscopy-assisted distal gastrectomy (LADG) is used to treat early gastric cancer with risk factors for regional lymph node metastasis. A survey conducted by the Japan Society for Endoscopic Surgery showed that 1428 LWRs, 260 IGMRs, and 2600 LADGs were performed between 1991 and 2001 in departments of endoscopic surgery in Japan. Laparoscopic gastrectomy for gastric cancer is still under development in Japan. According to short-term results reported by a small group of surgeons, laparoscopic approaches to gastric cancer provide for minimal invasion, early recovery, and decreased morbidity and mortality. If the advantages can be confirmed in one or more multicenter randomized control studies of the long-term outcome of patients undergoing laparoscopic gastrectomy for gastric cancer, the procedure should come into wide acceptance and use.

Endoluminal intragastric treatment of gastric carcinoma

SummaryEarly gastric cancer accounts for more than 50% of resected gastric cancer cases in Japan. Because of the increased incidence of early gastric cancer, endoluminal minimally invasive intragastric treatments have been developed. The rate of lymph node metastasis is very low in early gastric cancer, especially in mucosal cancer. There are two popular strategies in Japan for the management of patients with mucosal cancer: endoscopic mucosal resection (EMR) and intragastric mucosal resection (IGMR). EMR is more popular: from 1993 to 1997, over 35,000 cases of early gastric cancer have been treated by EMR in Japan. IGMR was developed in 1993, and 256 cases of early gastric cancer, which were not appropriate for EMR because of size and location, have been treated successfully by IGMR. These data suggest that in Japan 20%-30% of patients with early gastric cancer are treated by endoluminal intragastric procedures. In this paper we review the indications for, techniques pertaining to, and outcomes of EMR and IGMR in Japan.

Combined laparoscopic-endoscopic procedure in stomach carcinoma

The purpose of this review is to outline the laparoscopic-endoscopic procedures that we perform for early gastric cancer. These procedures were applied to 29 patients. Preoperative work-up included gastric endoscopy, barium X-ray examination, endoscopic ultrasonography, and histological examination, and surgery was performed in patients diagnosed as having mucosal gastric cancer for which endoscopic mucosal resection (EMR) was difficult. Laparoscopic wedge resection of the stomach using the lesion-lifting method, by which a wedge resection is made while pulling up the full-thickness gastric wall, was carried out in the 16 patients with lesions of the anterior wall, lesser curvature, and greater curvature of the stomach. On pathological examination of resected specimens, the surgical margin and lymphatic or venous invasion were negative in all these patients. The histological depth of the lesions was m (mucosal cancer) in 15 patients and sm1 (slight cancer infiltration into the submucosal layer) in one. This one patient later underwent gastrectomy but no lymph node metastases were found. Oral nutrition was resumed for a mean (+/- SD) of 2.9 +/- 0.8 days after operation, and the duration of hospitalization after operation was 12.3 +/- 3.4 days. The 13 patients with lesions of the posterior wall of the stomach and near the cardia or the pylorus received laparoscopic intragastric mucosal resection. Laparotomy was required in 1 of these patients due to intraoperative hemorrhage. The surgical margins were negative in all 12 patients in whom laparoscopic intragastric mucosal resection was successful. Lymphatic or venous invasion was positive in 2, both of whom had sm1 cancer lesions of both of these patients were located in the cardiac region, total gastrectomy was avoided, and careful observation is continued. Oral nutrition was resumed 4.0 +/- 1.6 days after operation, and the duration of hospitalization after operation was 12.0 +/- 3.5 days. In addition, no postoperative complication was noted after either procedure, and all patients have been recurrence free for a follow-up period of 460 months. Selected properly, these laparoscopic endoscopic procedures are considered to be curative and minimally invasive treatments for early gastric cancer.

Curative laparoscopic surgery for early gastric cancer: five years experience.

Sixty-one patients who were diagnosed with mucosal gastric cancer have been successfully treated with two laparoscopic techniques at our institute from March 1992 to March 1997. One is laparoscopic wedge resection of the stomach using a lesion-lifting method for lesions of the anterior wall, the lesser curvature, and the greater curvature of the stomach. The other is laparoscopic intragastric mucosal resection for lesions of the posterior wall of the stomach and near the cardia or the pylorus. Indications are as follows: (1) preoperatively diagnosed mucosal cancer; (2) <25 mm diameter elevated lesions; and (3) <15 mm diameter depressed lesions without ulcer formation. Patients were discharged in 4 to 8 days uneventfully. There was no major complication or mortality. The resected specimens had sufficient surgical margins horizontally (16 +/- 5 and 8 +/- 4 mm, respectively) and vertically. In one patient histologic examination revealed slight tumor infiltration into the submucosal layer with lymphatic invasion. He underwent gastrectomy with lymph node dissection 1 month after surgery. Otherwise, histologic examination revealed curative surgery. All patients in the series have survived during the 4- to 65-month follow-up period. There have been two recurrences in the series, both of which were found near the staple line 2 years after the initial surgery and were still mucosal lesions. They were successfully treated by open gastrectomy and laser irradiation. A separate early gastric cancer was found 2 years after the initial surgery in one patient, who then underwent curative open gastrectomy. In conclusion, if the patients are selected properly, these laparoscopic procedures are curative, minimally invasive treatment for early gastric cancer.