Determination of the Minimum Sample Amount for Capillary Electrophoresis-Fourier Transform Mass Spectrometry (CE-FTMS)-Based Metabolomics of Colorectal Cancer Biopsies.

The minimum sample volume for capillary electrophoresis-Fourier transform mass spectrometry (CE-FTMS) useful for analyzing hydrophilic metabolites was investigated using samples obtained from colorectal cancer patients. One, two, five, and ten biopsies were collected from tumor and nontumor parts of the surgically removed specimens from each of the five patients who had undergone colorectal cancer surgery. Metabolomics was performed on the collected samples using CE-FTMS. To determine the minimum number of specimens based on data volume and biological interpretability, we compared the number of annotated metabolites in each sample with different numbers of biopsies and conducted principal component analysis (PCA), hierarchical cluster analysis (HCA), quantitative enrichment analysis (QEA), and random forest analysis (RFA). The number of metabolites detected in one biopsy was significantly lower than those in 2, 5, and 10 biopsies, whereas those detected among 2, 5, and 10 pieces were not significantly different. Moreover, a binary classification model developed by RFA based on 2-biopsy data perfectly distinguished tumor and nontumor samples with 5- and 10-biopsy data. Taken together, two biopsies would be sufficient for CE-FTMS-based metabolomics from a data content and biological interpretability viewpoint, which opens the gate of biopsy metabolomics for practical clinical applications.

[A Case of Locally Advanced Unresectable Esophageal Cancer Treated with Nivolumab and Ipilimumab Therapy Followed by Surgery].

In cases of unresectable, locally advanced esophageal cancer, conversion surgery may be considered if chemotherapy produces favorable results and surgical resection is indicated. The use of immune checkpoint inhibitors in chemotherapy for esophageal cancer has expanded, and has increased the number of cases in which conversion surgery becomes possible. The patient in the present report had received a diagnosis of Stage Ⅳa esophageal carcinoma, and a prior nephroureterectomy discouraged the administration of platinum-based agents. Nivolumab and ipilimumab were administered as induction chemotherapy. Despite the achievement of stable disease, the patient's esophageal stricture deteriorated, necessitating surgical intervention. The resected specimen revealed that fewer than 50% of malignant cells remained viable and residual cancer cells were noticeably absent, particularly in the enlarged lymph nodes. We herein present the details of this case and discuss the literature concerning surgery following immune checkpoint inhibitor therapy.

Evaluation of the learning curve for robot-assisted rectal surgery using the cumulative sum method.

BACKGROUND: There is no clear evidence on the number of cases required to master the techniques required in robot-assisted surgery for different surgical fields and techniques. The purpose of this study was to clarify the learning curve of robot-assisted rectal surgery for malignant disease by surgical process. METHOD: The study retrospectively analyzed robot-assisted rectal surgeries performed between April 2014 and July 2020 for which the operating time per process was measurable. The following learning curves were created using the cumulative sum (CUSUM) method: (1) console time required for total mesorectal excision (CUSUM tTME), (2) time from peritoneal incision to inferior mesenteric artery dissection (CUSUM tIMA), (3) time required to mobilize the descending and sigmoid colon (CUSUM tCM), and (4) time required to mobilize the rectum (CUSUM tRM). Each learning curve was classified into phases 1-3 and evaluated. A fifth learning curve was evaluated for robot-assisted lateral lymph node dissection (CUSUM tLLND). RESULTS: This study included 149 cases. Phase 1 consisted of 32 cases for CUSUM tTME, 30 for CUSUM tIMA, 21 for CUSUM tCM, and 30 for CUSUM tRM; the respective numbers were 54, 48, 45, and 61 in phase 2 and 63, 71, 83, and 58 in phase 3. There was no significant difference in the number of cases in each phase. Lateral lymph node dissection was initiated in the 76th case where robot-assisted rectal surgery was performed. For CUSUM tLLND, there were 12 cases in phase 1, 6 in phase 2, and 7 cases in phase 3. CONCLUSIONS: These findings suggest that the learning curve for robot-assisted rectal surgery is the same for all surgical processes. Surgeons who already have adequate experience in robot-assisted surgery may be able to acquire stable technique in a smaller number of cases when they start to learn other techniques.

Intrathoracic omental herniation mimics posterior mediastinal lipomatous tumor.

Intrathoracic omental herniation is an esophageal hiatal hernia that does not involve the stomach and has been previously misdiagnosed as a lipomatous tumor. We report the case of a 72-year-old man who was referred to our hospital for investigation of a chest abnormal shadow. The large mediastinal mass with fat density was not recognized 5 years ago. Although it mimicked a mediastinal lipomatous tumor, we could preoperatively diagnose it as intrathoracic omental herniation. Contrast-enhanced computed tomography was effective in making an accurate diagnosis, showing the mass and vessels passing through the esophageal hiatus from the abdominal cavity. Laparoscopic surgery was performed, and the hiatus was repaired. To diagnose the mediastinal lipidic mass as intrathoracic omental herniation preoperatively can provide less invasive procedure.

Less invasive treatment for broad ligament hernia: A case report.

INTRODUCTION: Among diseases that cause small bowel obstruction, internal hernia may result in severe outcomes. Therefore, emergency laparotomy has been often performed, but it may be invasive. We experienced a case of a broad ligament hernia of the uterus, which is relatively rare among the cases of internal hernia that were treated by less invasive laparoscopic surgery. CASE PRESENTATION: A 71-year-old woman came to our hospital because of abdominal pain and vomiting. Abdominal computed tomography (CT) revealed a broad ligament hernia of the uterus without intestinal ischemia. Intestinal decompression was done by inserting an ileus tube (® Long Intestinal Tube, CLINY), followed by elective laparoscopic surgery. DISCUSSION: If intestinal ischemia can be ruled out, a less invasive laparoscopic surgery may be performed after intestinal decompression. Further, by detecting the cause of internal hernia, more safe and smooth surgery can be performed. These findings highlighted the importance of accurate CT diagnosis. CONCLUSION: In order to perform laparoscopic surgery for internal hernia, evaluation of the presence or absence of intestinal ischemia and detection of the cause of obstruction by preoperative abdominal CT are important.

[A Case Report of Gastric Cancer Excised after Neoadjuvant Chemotherapy and Long-Term Survival Achieved after NivolumabAdministration for Peritoneal Dissemination].

The patient was a 64-year-old man with Type 3 advanced cancer in the upper body of the stomach. The preoperative tumor marker value of CA19-9 was abnormally high, but there was no proof of distant metastasis or peritoneal dissemination. The first operation was an exploratory laparotomy due to direct tumor invasion to the pancreas. Systemic chemotherapy was performed for tumor reduction. First, S-1 plus cisplatin therapy was administered for 4 courses but discontinued because of renal dysfunction and thrombocytopenia. In the second-line therapy, ramucirumabplus paclitaxel therapy was administered for 7 courses. Since the tumor invasion to the pancreas turned to be clear based on a CT scan, total gastrectomy with regional lymphadenectomy was performed. However, 5 months after surgery, a single nodule appeared in the upper abdomen that was suspected to be peritoneal dissemination. Nivolumab therapy was administered for 16 months without tumor enlargement or any adverse effect. Recently, there has been a marked development in chemotherapy for gastric cancer. Unresectable cases became operable after the administration of appropriate chemotherapy. In our case, nivolumab therapy had no adverse effect. However, serious adverse effects have been reported by several authors which suggests that regular examinations for interstitial pneumonia, hypothyroidism, and other adverse effects are important.

[A Case Report of Gastric Cancer with Positive Peritoneal Lavage Cytology and Metachronous Schnitzler's Metastasis Treated with Multimodality Therapy].

A69 -year-old male patient with type 3 gastric cancer in pyloric antrum underwent distal gastrectomy with regional lymphadenectomy. Serosal infiltration of cancer tissue was found in the anterior wall of antrum, and the evaluation of peritoneal lavage cytology were positive. Pathological analysis showed the tumor was mainly consist of moderately tubular adenocarcinoma and strongly positive for HER2 stain. Postoperatively, combined therapy of capecitabine and trastuzumab was carried out, but cisplatin was excluded because of the patient's rejection. However, nine months after drug withdrawal, singular tumor located at left anterior side of rectum was detected by abdominal CT scan. Colonoscopy revealed its mucosal invasion and the result of biopsy was metastasis of gastric cancer, also known as Schnitzler's metastasis. Local radiation therapy aimed at the tumor was performed, followed by capecitabine and oxaliplatin therapy for 18 months. After the therapy, Schnitzler's metastatic lesion was disappeared and biopsy from colonic mucosa revealed there was no tumor tissue left. The patient has been in good health 5 years after surgery. This case suggests that multimodality therapy including radiation and chemotherapy might improve survival of gastric cancer patient with positive peritoneal lavage cytology and metachronous metastasis.

[Recurrence of a Giant Retroperitoneal Leiomyosarcoma Six Years after the Initial Surgery].

A 51-year-old man came to our department because of a large abdominal mass. CT, MRI, and sonography revealed a large tumor adjacent to the retroperitoneal area. A resection was performed, and histologically we confirmed the diagnosis as a leiomyosarcoma originating from the retroperitoneum. Six years after the initial surgery, the patient came to our outpatient department with a complaint of nausea. A relatively large tumor was seen on a CT scan that was causing obstruction of the duodenum. Another surgery was performed with the final diagnosis as a recurrence of the leiomyosarcoma. After 3 courses of adjuvant chemotherapy with eribulin, the patient presented with abdominal distension. CT revealed a very large tumor with massive invasion to the ileum and colon. This time, we considered the tumor unresectable, and administered chemotherapy with a combination of doxorubicin and ifosfamide. However, after 1 course, the patient's condition worsened and he died of the disease 3 months after the chemotherapy.