Purpose: The aim of the study is to investigate the indicators for optimal case selection and the number of cases required for surgery residents to perform elective laparoscopic cholecystectomy (LC) safely and achieve certification through training. Materials and Methods: A total of 124 cases of elective LC performed by five surgical residents in our department between April 2018 and December 2021 were analyzed. Learning curves were constructed using the cumulative sum (CUSUM) method for each resident's operative time to determine the number of cases needed for proficiency. Correlations between operative time and 13 preoperative factors were also examined. Result: The median age of the patients was 61 years and the male-to-female ratio was 64:60. Intraoperatively, the median operative time was 105 minutes and blood loss was 0 ml. There were no cases with conversion to open laparotomy or intraoperative complications. The median postoperative hospital stay was 3 days and there were no postoperative complications of Clavien-Dindo grade II or higher. The CUSUM analysis indicated an average requirement of 10.4 cases for achieving proficiency in the procedure. Among the 13 preoperative factors examined, only the presence of gallbladder wall thickening was significantly correlated with surgical time (P=0.005). Conclusion: Experience of about 10 cases as an operator is necessary for surgery residents to obtain certification in elective LC. Cases with gallbladder wall thickening might pose difficulties and warrant careful consideration by supervising surgeons when selecting suitable cases for training of residents.

Purpose: Chronic postoperative inguinal pain (CPIP) is a serious complication that impairs the quality of life of patients. In a survey conducted at our hospital, CPIP occurred in 7.6% of patients, and 2.2% of refractory cases required invasive treatment. The purpose of this study was to verify whether the recommendation in international guidelines of nerve anatomy awareness and recognition during surgery contributes to a reduction in the incidence of CPIP. Materials and Methods: Pain was assessed on a 6-point Numerical Rating Scale (NRS) (0–5) and CPIP was defined as NRS of 3 or higher at 3 months after surgery. Interventions were performed in 198 patients (207 lesions) who underwent elective inguinal hernia repair between 2016 and 2018 in our department. The intervention included 1) intraoperative nerve confirmation with a surgical record template, and 2) an outpatient visit 3 months after surgery, during which a questionnaire was used to investigate the intensity of pain in daily life. Result: Of 105 patients (108 lesions) who underwent anterior inguinal hernia repair and visited the outpatient clinic 3 months after surgery, 66% had all 3 nerves identified. CPIP occurred in 2 patients (1.9%), but both obtained relief from pain over time. Conclusion: These results suggest that nerve anatomy awareness and recognition during surgery may reduce the incidence of CPIP in patients undergoing anterior inguinal hernia repair.

A 37-year-old woman visited our emergency department with severe pain from the upper abdomen to the left lumbar region and frequent vomiting. She was diagnosed with gastric volvulus by contrast-enhanced CT and underwent emergency endoscopic repair. One month after this procedure, percutaneous endoscopic gastric wall fixation was performed using non-absorbable thread (2-0 PROLENE^®). The patient has had no recurrence since this time. Gastric volvulus is a disease in which the stomach is twisted beyond the physiological range. The disease rarely causes acute abdomen, but is important because it may lead to strangulation, necrosis, or perforation. Treatments for percutaneous endoscopic gastric wall fixation include nasogastric tube decompression, endoscopic repair, and surgery, but there have been few reports of this condition in Japan. Here, we report our experience of treatment of percutaneous endoscopic gastric wall fixation using a non-absorbable thread for gastric volvulus.

A 34-year-old woman presented with a complaint of swelling of the buttock. A physical examination indicated a subcutaneous soft elastic tumor. CT and MRI showed a 6-cm subcutaneous dumbbell-shaped cystic tumor in the buttock, extending into the pelvic cavity. Laparoscopic resection with a transsacral approach was performed without an accurate preoperative diagnosis. Laparoscopically we found a subcutaneous tumor in the buttock penetrating into the pelvic cavity on the dorsal side of the mesorectum, through the gap of the levator ani muscle around the coccygeal bone. The cystic tumor and coccygeal bone were totally resected. Pathological findings of the specimen revealed a cyst wall composed of squamous epithelium that contained atheromatous contents. The lesion was diagnosed as an epidermal cyst. The patient was discharged from hospital on the eighth postoperative day without any complications. There has been no recurrence of symptoms after surgery. An epidermal cyst is a benign tumor that is commonly experienced in daily medical practice. Malignant transformation of epidermal cysts are reported on rare occasions, and total resection of the tumor is recommended. This case shows that transsacral resection with laparoscopic surgery for cystic tumors extending from the buttocks into the pelvic cavity is a safe and appropriate surgical approach.

A 44-year-old man was diagnosed with gastric cancer and underwent laparoscopic distal gastrectomy, D2 lymph node dissection, and Billroth-I reconstruction. The histopathological diagnosis was pT2N0M0 Stage IB. At one-year follow-up, CT and PET-CT showed a mass in the #6 lymph node dissection area, which was suspected to be lymph node recurrence. Laparoscopic resection was performed and the mass was diagnosed as a desmoid tumor. Preoperative diagnosis of desmoid tumors is generally difficult. Mechanical stimulation by surgery is one of the mechanisms through which desmoid tumors develop, which makes differential diagnosis from recurrence difficult when such tumors occur after gastrectomy for gastric cancer. In cases with a low risk of recurrence, surgery for diagnosis is useful, and resection of other organs or chemotherapy can be avoided if recurrence can be ruled out. We report this case as an example of desmoid tumor that required differentiation from lymph node recurrence after gastrectomy for gastric cancer.

A 40-year-old woman presented to our hospital with a complaint of worsening lower abdominal pain that had persisted for 2 months. Blood and urine tests showed no abnormal findings, and a pregnancy test was negative. CT and MRI showed a 7-cm unilocular cyst, presumably of omental origin, but no other abnormal findings that could have caused the symptoms. For this reason, laparoscopic excision of the cyst was performed. Intraoperative laparoscopy revealed that the cyst was contiguous with the margins of the greater omentum, but not with any pelvic organs. Histopathology showed a 7-cm unilocular cyst with a wall covered with a monolayer ciliated epithelium. Immunostaining was positive for PAX8 and the cyst was thought to be homologous to a serous cystadenoma of the ovary. Postoperatively, the symptoms resolved. Serous cystadenomas commonly arise in the ovary. In sites other than the retroperitoneal space, there have been several reports of such cysts arising in the posterior mediastinum, but no reports of similar cysts in the greater omentum. The cyst in this case was presumed to be an ectopic epithelium of the fallopian tube or fimbriae migrating into the greater omentum. Symptoms such as those in this case are considered to be an indication for surgery.