Abdominal compartment syndrome as a complication of endoscopic carbon dioxide insufflation in a patient with malignant bowel obstruction: a case report.

BACKGROUND: A self-expandable metal stent is often placed as a bridge to elective surgical treatment of left-sided malignant obstruction of the colon because it allows for primary anastomosis without the need for a temporary stoma, which has a positive impact on the patient's quality of life. However, although a relatively safe procedure, colonic stenting can have complications that require emergency surgery. This case report describes a rare case of abdominal compartment syndrome that occurred as a complication of endoscopic insufflation during colonic stenting. CASE PRESENTATION: The patient was a 72-year-old woman who presented complaining of several days of constipation and loss of appetite. Computed tomography of the abdomen revealed obstruction of the sigmoid colon by a tumor. There were no symptoms or computed tomography findings to suggest perforation. Therefore, an attempt was made to insert a self-expandable metal stent. Acute respiratory disturbance and a change in consciousness occurred during the stenting procedure, with marked abdominal distention. Abdominal compartment syndrome was diagnosed and treated by decompressive laparotomy. CONCLUSIONS: To the best of our knowledge, this is the first reported case of abdominal compartment syndrome as a complication of endoscopic insufflation during colonic stenting. The possibility of abdominal compartment syndrome should be considered if acute respiratory disturbance or altered consciousness occurs during endoscopic procedure in a patient with malignant bowel obstruction.

Endoscopic carbon dioxide insufflation tolerance test on the anal sphincter for anorectal hypofunction: a pilot and feasibility study.

Background: Anorectal function deteriorates with age. The diagnostic performance of the endoscopic pressure study integrated system (EPSIS), an endoscopic carbon dioxide (CO2) insufflation stress test of the lower esophageal sphincter has been previously evaluated as a diagnostic tool for gastroesophageal reflux disease. We aimed to evaluate the applicability of EPSIS in improving anorectal function. We hypothesized that EPSIS can be applied to the diagnosis of lower gastrointestinal tract disorders. Methods: This was a pilot, single-center, retrospective study using prospectively collected data between December 2021 and March 2022. It was designed to evaluate the differences in EPSIS rectal pressure measurements between older (≥80 years) and younger (<80 years) patients. At the end of the screening colonoscopy, the colonoscope was fixed in a retroflex position. When bowel movement was observed, CO2 was insufflated to the point where gas leakage occurred through the anus. The measured maximum pressure was defined as EPSIS-rectal pressure max (EPSIS-RP max) and compared between the groups. Results: Overall, 30 patients were included and examined. The median ages of the <80 and ≥80 years' groups were 53 (range: 27-79) and 82 (range: 80-94) years, respectively, with corresponding median measured EPSIS-RP max of 18.7 (range: 8.5-30.2) and 9.8 (range: 5.4-22.3) mmHg (P<0.001). Conclusions: Measurement of maximum rectal pressure illustrates the age-related decline in physiological anorectal function. Future studies should consider a loading test using EPSIS to quantify the decline in anorectal function and use it as a routine tool for screening and adjunctive diagnosis of anorectal hypofunction.

Determination of esophageal squamous cell carcinoma and gastric adenocarcinoma on raw tissue using Raman spectroscopy.

BACKGROUND: Cancer detection is a global research focus, and novel, rapid, and label-free techniques are being developed for routine clinical practice. This has led to the development of new tools and techniques from the bench side to routine clinical practice. In this study, we present a method that uses Raman spectroscopy (RS) to detect cancer in unstained formalin-fixed, resected specimens of the esophagus and stomach. Our method can record a clear Raman-scattered light spectrum in these specimens, confirming that the Raman-scattered light spectrum changes because of the histological differences in the mucosal tissue. AIM: To evaluate the use of Raman-scattered light spectrum for detecting endoscop-ically resected specimens of esophageal squamous cell carcinoma (SCC) and gastric adenocarcinoma (AC). METHODS: We created a Raman device that is suitable for observing living tissues, and attempted to acquire Raman-scattered light spectra in endoscopically resected specimens of six esophageal tissues and 12 gastric tissues. We evaluated formalin-fixed tissues using this technique and captured shifts at multiple locations based on feasibility, ranging from six to 19 locations 200 microns apart in the vertical and horizontal directions. Furthermore, a correlation between the obtained Raman scattered light spectra and histopathological diagnosis was performed. RESULTS: We successfully obtained Raman scattered light spectra from all six esophageal and 12 gastric specimens. After data capture, the tissue specimens were sent for histopathological analysis for further processing because RS is a label-free methodology that does not cause tissue destruction or alterations. Based on data analysis of molecular-level substrates, we established cut-off values for the diagnosis of esophageal SCC and gastric AC. By analyzing specific Raman shifts, we developed an algorithm to identify the range of esophageal SCC and gastric AC with an accuracy close to that of histopathological diagnoses. CONCLUSION: Our technique provides qualitative information for real-time morphological diagnosis. However, further in vivo evaluations require an excitation light source with low human toxicity and large amounts of data for validation.

A case of acute cholecystitis with abnormally high CA19-9.

BACKGROUND: CA19-9 is strongly expressed in malignant tumors of the digestive system and is widely used as a marker for gastrointestinal cancer. In this report, we describe a case of acute cholecystitis in which CA19-9 was markedly elevated. CASE PRESENTATION: A 53-year-old man was admitted to our hospital with a diagnosis of acute cholecystitis after being referred to our hospital with a chief complaint of fever and right hypochondrial pain. CA19-9 was abnormally high at 17,539.1 U/ml. Although the possibility of malignancy was considered, there was no obvious malignant lesion on imaging; the patient was diagnosed with cholecystitis, and laparoscopic cholecystectomy was performed the day after admission. The surgical specimen showed no malignant findings either grossly or in the final pathological examination. There were no complications in the patient's postoperative course, and he was discharged from the hospital on the third postoperative day. CA19-9 level quickly returned to within normal range after surgery. CONCLUSIONS: In acute cholecystitis, CA19-9 levels exceeding 10,000 U/ml are very rare. We report a case of acute cholecystitis without malignant findings despite a high CA19-9 level.

Highly accurate colorectal cancer prediction model based on Raman spectroscopy using patient serum.

BACKGROUND: Colorectal cancer (CRC) is an important disease worldwide, accounting for the second highest number of cancer-related deaths and the third highest number of new cancer cases. The blood test is a simple and minimally invasive diagnostic test. However, there is currently no blood test that can accurately diagnose CRC. AIM: To develop a comprehensive, spontaneous, minimally invasive, label-free, blood-based CRC screening technique based on Raman spectroscopy. METHODS: We used Raman spectra recorded using 184 serum samples obtained from patients undergoing colonoscopies. Patients with malignant tumor histories as well as those with cancers in organs other than the large intestine were excluded. Consequently, the specific diseases of 184 patients were CRC (12), rectal neuroendocrine tumor (2), colorectal adenoma (68), colorectal hyperplastic polyp (18), and others (84). We used the 1064-nm wavelength laser for excitation. The power of the laser was set to 200 mW. RESULTS: Use of the recorded Raman spectra as training data allowed the construction of a boosted tree CRC prediction model based on machine learning. Therefore, the generalized R 2 values for CRC, adenomas, hyperplastic polyps, and neuroendocrine tumors were 0.9982, 0.9630, 0.9962, and 0.9986, respectively. CONCLUSION: For machine learning using Raman spectral data, a highly accurate CRC prediction model with a high R 2 value was constructed. We are currently planning studies to demonstrate the accuracy of this model with a large amount of additional data.

Combination of laparoscopic and endoscopic approaches for neoplasia with non-exposure technique (CLEAN-NET) for gastric submucosal tumors: updated advantages and limitations.

Laparoscopic and endoscopic cooperative surgery (LECS) for gastric submucosal tumors (SMTs) has been developed under the concept of resecting gastric tumors with both complete curability and preserving organ functions. Precise resection is obtained by classical LECS, however, concerns regarding intraoperative bacterial infection and dissemination of the tumor cells into the abdominal cavity by LECS with exposure technique still remain. To prevent these concerns, several LECS-related procedures with non-exposure techniques, such as combination of laparoscopic and endoscopic approaches for neoplasia with non-exposure technique (CLEAN-NET) and non-exposed endoscopic wall-inversion surgery (NEWS), have been reported to be safe and feasible. Classical LECS, CLEAN-NET, and NEWS have the same concept, however, each has its own different characteristic procedures; exposure or non-exposure technique, inversion of the tumor into or outer the lumen, retrieval of tumor per oral or through the abdominal cavity, and dominance in the role of the endoscopist or the laparoscopic surgeon. Familiarization with these procedure details is important to understand their indications, advantages and limitations, resulting in providing a tailored minimally invasive surgery for patients. The main scope of this review article is to introduce readers to the clinical application, procedure, and results of CLEAN-NET, both from previous literatures and from our experience, as well as to offer a closer look at its advantages and limitations while comparing with other LECS procedures from the viewpoint of introducing CLEAN-NET first.

Raman spectroscopy for the diagnosis of unlabeled and unstained histopathological tissue specimens.

AIM: To investigate the possibility of diagnosing gastric cancer from an unstained pathological tissue using Raman spectroscopy, and to compare the findings to those obtained with conventional histopathology. METHODS: We produced two consecutive tissue specimens from areas with and without cancer lesions in the surgically resected stomach of a patient with gastric cancer. One of the two tissue specimens was stained with hematoxylin and eosin and used as a reference for laser irradiation positioning by the spectroscopic method. The other specimen was left unstained and used for Raman spectroscopy analysis. RESULTS: A significant Raman scattering spectrum could be obtained at all measurement points. Raman scattering spectrum intensities of 725 cm-1 and 782 cm-1, are associated with the nucleotides adenine and cytosine, respectively. The Raman scattering spectrum intensity ratios of 782 cm-1/620 cm-1, 782 cm-1/756 cm-1, 782 cm-1/1250 cm-1, and 782 ​​cm-1/1263 cm-1 in the gastric adenocarcinoma tissue were significantly higher than those in the normal stomach tissue. CONCLUSION: The results of this preliminary experiment suggest the feasibility of our spectroscopic method as a diagnostic tool for gastric cancer using unstained pathological specimens.

Randomized phase III trial comparing surgery alone to UFT + PSK for stage II rectal cancer (JFMC38 trial).

BACKGROUND: We conducted a randomized phase III trial comparing tegafur/uracil (UFT) and Polysaccharide-K (PSK) to surgery alone in curatively resected stage II rectal cancer patients. METHODS: Patients were randomly assigned to receive either UFT and PSK or surgery alone in a 1:1 ratio with a minimization method to balance the treatment allocation. The primary end point of this study was the disease-free survival (DFS). The secondary end point was the overall survival (OS). RESULTS: From October 2011 to February 2013, 111 patients were registered from 62 institutions. The study was prematurely closed due to poor accrual after reaching 20% of its goal. The patients' characteristics were similar between the UFT and PSK group and the surgery-alone group. The DFS rate was 76.0% at 3 years and 65.1% at 5 years in the UFT and PSK arm and 84.0% at 3 years and 77.2% at 5 years in the surgery-alone arm. The DFS was slightly worse in the UFT + PSK arm than in the surgery-alone arm, but the difference did not reach statistical significance (log rank p = 0.102). The OS rate was 100% at 3 years and 97.9% at 5 years in the UFT + PSK arm, while that was 100% at 3 years and 93.4% at 5 years in the surgery-alone arm. The OS was similar in the UFT + PSK arm and surgery-alone arm (p = 0.533). CONCLUSION: The present study suggests that UFT and PSK are not attractive candidates to advance to the next phase III study because the DFS was slightly worse in the UFT and PSK arm than in the surgery-alone arm.

Questionnaire survey regarding the current status and controversial issues concerning reconstruction after gastrectomy in Japan.

The Japanese Society for the Study of Postoperative Morbidity after Gastrectomy conducted a nationwide questionnaire survey to clarify the current status of reconstruction after gastrectomy. One hundred and forty-five institutions (66%) responded to the survey. The questionnaire dealt with the reconstruction after a distal gastrectomy, pylorus-preserving gastrectomy (PPG), total gastrectomy, and proximal gastrectomy. The most common method of reconstruction after distal gastrectomy was Billroth I in 112 institutions (74%), and Roux-en-Y (RY) in 30 (21%). Seventy-seven institutions (53%) responded to the PPG questions. The lengths of the antral cuff were widely distributed among the institutions. Segmental gastrectomy was performed by 23 institutions for limited cases. The most common method of reconstruction after total gastrectomy was RY in 138 institutions (95%). Reconstruction with a pouch after total gastrectomy was done in 26 institutions (18%). The most common reconstructions after proximal gastrectomy were esophagogastrostomy in 69 institutions (48%), jejunal interposition in 41 (28%), double tract in 19 (13%) and pouch reconstruction in 6 (7%). Although most Japanese surgeons are concerned about the revised methods of reconstruction and quality of life after gastrectomy, surgeons have not yet reached a full consensus on these issues.

Gastrointestinal cancer metastasis and lymphatic advancement.

The role of angiogenesis in the growth of solid tumors is well established, but the role of lymphatic vessels and the relationship between lymphangiogenesis and tumor spread are less clear. Recently, the molecular pathway that signals lymphangiogenesis and specific markers for lymphatic endothelium have been discovered; however, the lymphatic pathway of cancer metastasis is only partly clarified. Several investigators from the mid 20th century indicated the existence of lymphatico-venous communications, and some observed the retrograde filling of lymph flow and lymphatico-venous communication in obstructive lymphopathy. In the 1960s Burn reported the importance of lymphovenous communication in his clinical and animal experimental data. Thus, the role of potential peripheral lymphatico-venous communication must be considered in the mechanism of cancer metastasis. We observed the lymphatico-venous (portal) communication, as well as lymph retention and reflux, in a rat model of mesenteric lymph vessel obstruction. Based on the phenomenon of lymphatico-venous communication and lymph flow reflux by lymphatic obstruction, we speculate that tumor cell obstruction in the lymph system will lead to the establishment of liver and/or peritoneal metastasis. Clinically, we observed extranodal cancer invasion in a model of lymphatic obstruction, and noted a strong relationship between extranodal invasion and liver or peritoneal metastasis. Thus, the existence of peritoneal and liver metastasis via a lymphatic pathway should be considered.

Association of gastric and intestinal phenotypic marker expression of gastric carcinomas with tumor thymidylate synthase expression and response to postoperative chemotherapy with 5-fluorouracil.

PURPOSE: It is well known that both gastric and intestinal phenotypic markers are expressed in gastric carcinomas, irrespective of their histological type. In the present study, the associations among phenotypic marker expression of gastric carcinomas, tumor thymidylate synthase (TS) expression, and the chemotherapeutic response to 5-fluorouracil (5-FU) were examined. METHODS: The gastric and intestinal phenotypic marker expression of the tumor was determined by the combination of the expression of human gastric mucin (HGM), MUC6, MUC2, and CD10, and was evaluated in comparison with tumor TS expression in 137 advanced gastric carcinomas in 137 patients (75 with postoperative chemotherapy with 5-FU and 62 without postoperative chemotherapy). Tumors were classified into the gastric- (G-), gastric and intestinal mixed- (GI-), intestinal- (I-), or unclassified- (UC-) phenotype according to the immunopositivity of HGM, MUC6, MUC2, and CD10 stainings. The associations among the gastric and intestinal phenotypic marker expression of the tumor, tumor TS expression, effect of postoperative chemotherapy with 5-FU, and the patient's prognosis were examined. RESULTS: Of the 137 gastric carcinomas, 48 (35.0%), 58 (42.3%), 23 (16.8%), and 8 (5.8%)were classified as the G-, GI-, I- and UC-phenotype, respectively. The high TS expression of more than 25% tumor cell positivity was found in 25 (52.1%) of the 48 G-phenotype tumors, 39 (67.2%) of the 58 GI-phenotype tumors, 18 (78.3%) of the 23 I-phenotype tumors, and 4 (50.0%) of the 8 UC-phenotype tumors. The I-phenotype tumors were significantly correlated with the higher rate of the high TS expression as compared with the G-phenotype tumors (P<0.05). Among 48 patients with the G-phenotype tumor, the 5-year survival rate in patients with and without postoperative chemotherapy was 39.7 and 27.8%, respectively. The patients with postoperative chemotherapy had a significantly better prognosis than those without postoperative chemotherapy (P<0.05). Conversely, there were no significant correlations between the presence of postoperative chemotherapy and the patient's prognosis among patients with GI-, I-, and UC-phenotype tumors. CONCLUSIONS: These results indicate that postoperative chemotherapy with 5-FU could be effective for patients with the G-phenotype tumor, since the incidence of intratumoral expression of TS, the target enzyme of 5-FU, is significantly low in G-phenotype tumors.