Recently single port surgery has gradually been widespread. From June 2009 to June 2010, eight cases with gastric tumors were treated with this technique in our department. Patients were five males and three females, and their ages ranged from 51 to 69 years old. The average operation time was 161.9 minutes. One case was pathologically diagnosed as gastric cancer and underwent total gastrectomy. One case was diagnosed as Schwannoma and six cases were diagnosed as gastrointestinal stromal tumor (GIST) of the stomach. Comparing with conventional laparoscopic surgery and open surgery, single port laparoscopic surgery may be useful for treating gastric tumors for the purpose of diagnosis and/or treatment. Introduction: Laparoscopic surgery for the stomach disease has been performed for the patient mainly suffering from early gastric cancer from the early 1990s (1)). According to the spread of laparoscopic surgery, instruments for laparoscopic surgery have rapidly been improved. Recently single port surgery has gradually been widespread 2). According to "Clinical practice guidelines for gastrointestinal stromal tumor (GIST) in Japan" (3)), submucosal tumor of gastrointestinal tract whose size is less than 50 mm might be treated by laparoscopic technique. From June 2009, we performed single port surgery to treat theses cases. We compare this technique with conventional laparoscopic surgery and open surgery against gastric tumors. Patients and Procedure: We began performing the single port surgery in June 2009. Formerly we treated patients with gastric submucosal tumors whose size were less than 50 mm by conventional laparoscopic technique (using four or five ports). For patients with gastric submucosal tumors whose sizes were larger than 50 mm or whose locations were close to pylorus ring or esophago-gastric junction, we chose open surgery. From June 2009 to June 2010, eight cases with gastric tumors were treated with single port laparoscopic technique (SILS group). From 2004 to 2008, eight cases were treated with conventional laparoscopic surgery (CL group), and from 2005 to 2009, eleven cases were treated with open surgery (Open group). We performed the wedge resection of the stomach for gastric tumor through a 2.5 cm incision at umbilical portion. Under general and epidural anesthesia, a 2.5 cm incision at umbilicus was made, SILSTM port was inserted into the incision and pneumoperitoneum was performed at pressure of 10 mmHg by carbon dioxide (Figure 1). Wedge resection of the stomach was performed by linear staplers under both endoscopic and laparoscopic views for confirmation of the tumor location. Results: In SILS group, there were five males and three females, and their ages ranged from 51 to 69 years old. The size of their tumors ranged from 27 mm to 46 mm in diameter. The average operation time was 161.9 minutes (range, 112-279 min). One case was converted to conventional laparoscopic surgery. One case was pathologically diagnosed as gastric cancer and underwent total gastrectomy in four weeks after SILS surgery (Figure 2). One case was diagnosed as Schwannoma (Figure 3) and six cases were diagnosed as gastrointestinal stromal tumor (GIST) of the stomach (Figure 4). All patients could restart oral intake within 3 days after operation (average: 2.5 POD) and the average hospital stay after operation was 7.0 days. At this writing, there have been no recurrences. In CL group, there were three males and five females, and five males and six females in Open group. The average sizes of their tumors were 38 mm (CL group) and 77 mm (Open group). The average operation times were 149 minutes (CL group) and 183 min (Open group). Cases of CL group consisted of six GISTs, one Schwannoma and one aberrant pancreas and cases of Open group were eight GISTs, one Schwannoma and two aberrant pancreases. Average post-operative day of restarting oral intake were 2.9 POD in CL group and 3.8 in Open group. Average hospital stays after operation were 7.9 days and 9.6 days respectively (Table). Discussion: Pre-operative diagnosis of one case in SILS group was hamartomatous inverted polyp and surgical treatment was performed for the purpose of getting pathological diagnosis. Another case in SILS group was diagnosed as GIST by fine needle aspiration biopsy under endoscopic ultrasonography. Other six cases in SILS group were detected as submucosal tumors and were not histologically diagnosed pre-operatively. Single port laparoscopic procedure may be useful for the purpose of diagnosis. During single port laparoscopic procedure we should make a field of vision by one forceps and one additional retractor, but forceps for single port laparoscopic surgery that are available at present can not grasp tissue as firm as conventional ones, so keeping a sufficient field of vision might be difficult. BMI of the patient should be taken into consideration when single port laparoscopic surgery is indicated. Operation times of this surgery were more than two hours. Forceps for this procedure are different from ordinal ones, so we should drill and get accustomed to the instruments. Background of the patients in each groups were different from each other, but at least in SILS group restarting oral intake and discharge were earlier than CL and Open group. We should compare postoperative QOL of patients treated by SILS procedure with that of patients treated by conventional laparoscopic surgery or open surgery. In the second operation of gastric cancer case, there was little adhesion in the peritoneal cavity, so this procedure might be useful for laparoscopic examination such as checking peritoneal dissemination. Also sleeve gastrectomy by SILS technique for the purpose of bariatric surgery was reported 4). Application of SILS may spread over various conditions. Recently new instrument for single port laparoscopic surgery was reported 5). At this time, commercially available instruments for SILS technique might be difficult to use robotic surgery, because handling parts of the instruments interfere with each other. Improvement of instruments of laparoscopic surgery should make it possible for us to apply SILS technique to robotic surgery. Conclusions: The single port laparoscopic surgery may be useful for treating gastric tumors for the purpose of diagnosis and/or treatment. Comparing with conventional laparoscopic surgery and open surgery, this procedure may require longer operation time, but may lead to shorter hospital stay. Impact upon patients' QOL is controversial. Indication of this procedure requires a further investigation.
