Retroperitoneal solitary neurofibroma mimicking lymph node metastasis of colon cancer: a case report.

BACKGROUND: A neurofibroma is a benign tumor that arises from Schwann cells and neurofibromas occur throughout the skin of neurofibromatosis type 1 (NF-1: Von Recklinghausen's disease) patients. A retroperitoneal solitary neurofibroma without any clinical signs of NF1 has been rarely reported. Herein, we present a case of a retroperitoneal solitary neurofibroma mimicking lymph node metastasis of colon cancer as well as a literature review. CASE PRESENTATION: An 80-year-old woman with abdominal pain and nausea was transported and diagnosed with bowel obstruction arising from sigmoid colon cancer A colonic stent was inserted to alleviate the bowel obstruction. A computed tomography scan with contrast revealed a liver tumor in segment 3, and an enlarged lymph node around the abdominal aorta. Whole-body 18F-fluorodeoxyglucose-positron emission tomography-CT (FDG-PET-CT) examine revealed increased FDG uptake in the liver tumor and enlarged lymph node. Liver and distant lymph node metastasis were diagnosed and we made a plan for a two-stage operation of the colon cancer and the metastatic lesions because laparotomy resection was needed for the retroperitoneal lymph node. Laparoscopic sigmoid colectomy was performed first. Pathological examination showed a tubular adenocarcinoma. A laparotomy for the metastatic lesions was performed to ensure complete lymph node dissection secondly. Histopathological findings of the liver tumor showed metastasis of sigmoid colon cancer. However, the tissue regarded as the enlarged lymph node was diagnosed as a neurofibroma. No metastasis and recurrence were observed. CONCLUSION: Although most neurofibromas are benign, malignant transformation of a neurofibroma is possible. PET-CT showed our patient had a high accumulated retroperitoneal tumor co-existing with colon cancer and liver metastasis. The treatment strategy of a solitary neurofibroma must be selected carefully considering the site of occurrence and the patient's background and aggressive resection of a tumor co-existing with another malignant tumor is needed.

Reemployment and Recovery from Stigma after Metabolic/Bariatric Surgery: A Case Report and Review.

Bariatric surgery is performed worldwide to address morbid obesity. The benefits of this surgery are weight loss and a decrease in obesity-related complications. The relationship between metabolic/bariatric surgery and reemployment has been evaluated in Western countries, but few such studies have been performed in Japan because the number of metabolic/bariatric surgeries is small. Only a limited number of Japanese studies have evaluated the effects of bariatric surgery on obesity stigma, which affects employment and advancement opportunities for obese persons and may result in dismissal. We describe a case of bariatric surgery for a 39-year-old man who was dismissed from his job because of morbid obesity. Traditional weight loss methods failed to maintain weight loss and, preoperatively, the patient was receiving treatment for type 2 diabetes, hypertension, and abnormal lipid metabolism. He underwent sleeve gastrectomy and lost 50.4 kg (percent excess weight loss: 68.1%) in the first postoperative year. All medications were stopped after improvement in the results of laboratory blood tests and he was reemployed at 8 months after surgery. Increased social activity associated with employment is a factor in suppressing rebound weight gain after bariatric surgery, and weight loss associated with bariatric surgery helps decrease anti-obesity social stigma.

Laparoscopic Repair Using Self-Fixating Mesh in an Adult Patient with a Sciatic Hernia and Irreducible Small Bowel: A Case Report and Literature Review.

Sciatic hernia is a rare type of pelvic floor hernia. The herniated tissue can include the ureter, small and large bowel, and ovary, among other tissues. Only a few cases of laparoscopic treatment for a sciatic hernia with small-bowel incarceration have been reported. We report our experience using a laparoscopic approach for treatment of sciatic hernia in an 83-year-old woman and review the literature on sciatic hernias. The patient was referred to our hospital complaining of constipation and abdominal bloating. Computed tomography (CT) scanning showed a right sciatic hernia containing the small bowel. Laparoscopic repair of the sciatic hernia was performed using a self-fixating mesh. The patient was discharged after an uneventful postoperative course and has not developed abdominal bloating or constipation postoperatively. In conclusion, a sciatic hernia was successfully repaired using a laparoscopic trans-preperitoneal approach and ProGrip Self-Fixating Mesh.

Periappendiceal fluid collection on preoperative computed tomography can be an indication for interval appendectomy: a retrospective study.

BACKGROUND: The treatment strategies for acute appendicitis, such as emergency appendectomy (EA), interval appendectomy (IA), and repeating nonoperative management (NOM), are controversial. In this study, we examined the preoperative factors that can be used to distinguish which patients should undergo IA. METHODS: We retrospectively identified 902 patients who underwent surgery for appendicitis in our hospital from January 2010 to December 2021. Of these patients, 776 were included in this study. The patients were divided into two groups: those with a periappendiceal fluid collection (PAFC) on preoperative computed tomography (PAFC-positive group, n = 170) and those without a PAFC (PAFC-negative group, n = 606). In each group, we compared patients who underwent EA and IA. RESULTS: In the PAFC-positive group, patients who underwent EA had a significantly higher postoperative complication rate than those who underwent IA (40.5% vs. 24.0%, p = 0.037). In the multivariate analysis, only the presence of PAFC was significantly associated with an increased risk of postoperative complications (odds ratio, 7.11; 95% confidence interval, 2.73-18.60; p < 0.001). The presence of PAFC alone was not significantly associated with an increased risk of IA or NOM failure (odds ratio, 1.48; 95% confidence interval, 0.19-11.7; p = 0.71). The rate of neoplasia on pathologic examination was significantly higher in the PAFC-positive than PAFC-negative group (7.6% vs. 1.5%, p < 0.001); the rate of carcinoma was also higher in the PAFC-positive group (2.4% vs. 0.17%, p = 0.02). CONCLUSIONS: The presence of PAFC on preoperative computed tomography was found to be a risk factor for postoperative complications but not IA or NOM failure. It was also correlated with neoplasia as the etiology of appendicitis. Therefore, PAFC positivity is useful as an indication for IA.

Förster resonance energy transfer (FRET)-Labeled nanoprobe enables real-time diagnosis of pancreatic juice activation due to postoperative pancreatic fistula.

OBJECTIVES: Postoperative pancreatic fistula (POPF) subsequent to pancreatectomy often causes activation of pancreatic juice, resulting in serious complications. In POPF, the types of pancreatic juices found are active and inactive, and the identification of these two types of pancreatic juice greatly contributes to the development of postoperative management after pancreatectomy. This study reports favorable results of the clinical application of the Förster resonance energy transfer (FRET) nanoprobe that was independently developed to distinguish between the active and inactive types of pancreatic juice. METHODS: The FRET nanoprobe developed was a nanoprotein capsule. It exuded a red color when the capsule structure was maintained. When activated protease in the pancreatic juice acts on it, the capsules are reduced quantitatively and FRET is abolished, resulting in a change in color from red to green. Pancreatic juice activation can be measured by the FRET signal. A total of 117 drainage fluid samples from 16 postpancreatoduodenectomy cases were obtained and evaluated. RESULTS: The diagnosis of pancreatic juice activation was possible using the FRET signal with a cut-off value of 1.6. Pancreatic juice activation was not associated with drainage fluid amylase (AMY) levels. The results demonstrated that pancreatic juice was activated when drainage fluid was infected. CONCLUSION: The use of a FRET nanoprobe enabled real-time detection of the presence or absence of pancreatic juice activation in pancreatic fistula after pancreatic surgery. There was an adequate correlation between infection and pancreatic juice activation regardless of drain AMY levels.

Use of a Novel Open Posterior Wall Technique for Laparoscopic Excision of Hydrocele of the Canal of Nuck in an Adult Female: Case Report.

Complete surgical excision is the standard treatment for hydrocele of the canal of Nuck. We developed a novel open posterior wall technique for laparoscopic transabdominal pre-peritoneal (TAPP) excision. A 38-year-old woman with a 5-month history of a painless reducible lump in the right groin had recently noticed a slight increase in the size of lump. Computed tomography showed a simple cystic lesion measuring 30 × 27.5 mm. We performed laparoscopic excision of the hydrocele by using the TAPP approach and the open posterior wall technique developed by us. Complete excision of the hydrocele was satisfactorily performed because the region from the external inguinal ring to the periphery could be clearly observed. After an uneventful postoperative course, the patient was discharged. Laparoscopic TAPP excision with open posterior wall technique was useful for complete excision of hydrocele of the canal of Nuck.

Is the Laparoscopic Approach Feasible for Reduction and Herniorrhaphy in Cases of Acutely Incarcerated/Strangulated Groin and Obturator Hernia?: 17-Year Experience from Open to Laparoscopic Approach.

Purpose: Management strategies for acutely incarcerated/strangulated groin and obturator hernias may differ from institution to institution, although, conventionally, the open approach has been used. Recently, laparoscopic transabdominal preperitoneal (TAPP) repair and totally extraperitoneal (TEP) repair have become commonly used operative procedures for the repair of groin hernias. It is unclear whether laparoscopic reduction and herniorrhaphy can be successfully accomplished in all cases. This study was aimed at assessing the effectiveness of laparoscopic treatment. Methods: We conducted a prospective clinical trial of the laparoscopic approach from December 2011 and comparatively analyzed the surgical outcomes between the open and laparoscopic approaches for incarcerated/strangulated hernias seen from December 2000 to March 2017. Results: The open approach for repair was used in 54 patients (50.9%) and the laparoscopic approach in 52 patients (49.1%). There was 1 case in which from the laparoscopic approach to laparotomy (1.9%) was required. The operation time treated by the laparoscopic approach was significantly longer than the open approach (126.4 minutes versus 104.6 minutes; P = .0079); however, the incidence of postoperative complications and the postoperative length of hospitalization were also less in the former group than in the latter group (3.9% versus 18.5%; P = .0172 and 5.6 days versus 14.7 days; P = .0096). Second-stage TAPP herniorrhaphy was performed in 7 patients (15.2%) after bowel resection or closure of bowel perforation, and first-stage TEP herniorrhaphy was performed in 1 patient after bowel resection. There was no case of mesh infection in the group treated by the laparoscopic approach, and there was 1 case of mesh infection in the group treated by the open approach. The mortality rate was 0% in the group treated by the laparoscopic approach. Conclusions: Laparoscopic reduction and herniorrhaphy for acutely incarcerated/strangulated groin and obturator hernias is effective, safe, and feasible.

In vivo redox metabolic imaging of mitochondria assesses disease progression in non-alcoholic steatohepatitis.

Given the rising incidence of non-alcoholic fatty liver disease (NAFLD) in both adults and children, the development of a non-invasive diagnostic method for assessing disease progression to non-alcoholic steatohepatitis (NASH) has become an important research goal. Currently available non-invasive imaging technologies are only able to assess fat accumulation in the liver. Therefore, these methods are not suitable for a precise diagnosis of NASH. The standard diagnostic technique for NASH, liver biopsy, has several drawbacks, including the higher risk of complications that accompanies invasive procedures. Here, we demonstrated that in vivo mitochondrial redox metabolism was dramatically altered at an early stage, before histopathological changes, and NASH could be accurately diagnosed by in vivo dynamic nuclear polarization-magnetic resonance imaging, with carbamoyl-PROXYL as a molecular imaging probe. In addition, this technique was feasible for the diagnosis of NASH compared with histopathological findings from biopsies. Our data reveal a novel method for monitoring the dynamics of redox metabolic changes in NAFLD/NASH.

Noninvasive mapping of the redox status of dimethylnitrosamine-induced hepatic fibrosis using in vivo dynamic nuclear polarization-magnetic resonance imaging.

Hepatic fibrosis is a chronic disorder caused by viral infection and/or metabolic, genetic and cholestatic disorders. A noninvasive procedure that enables the detection of liver fibrosis based on redox status would be useful for disease identification and monitoring, and the development of treatments. However, an appropriate technique has not been reported. This study describes a novel method for assessing the redox status of the liver using in vivo dynamic nuclear polarization-magnetic resonance imaging (DNP-MRI) with the nitroxyl radical carbamoyl-PROXYL as a molecular imaging probe, which was tested in dimethylnitrosamine-treated mice as a model of liver fibrosis. Based on the pharmacokinetics of carbamoyl-PROXYL in control livers, reduction rate mapping was performed in fibrotic livers. Reduction rate maps demonstrated a clear difference between the redox status of control and fibrotic livers according to the expression of antioxidants. These findings indicate that in vivo DNP-MRI with a nitroxyl radical probe enables noninvasive detection of changes in liver redox status.

Förster Resonance Energy Transfer-Based Self-Assembled Nanoprobe for Rapid and Sensitive Detection of Postoperative Pancreatic Fistula.

Postoperative pancreatic fistula (POPF) is the most serious and challenging complication following gastroenterological surgery. Activated pancreatic juice leaking from the organ remnant contains proteases that attack the surrounding tissue, potentially leading to severe inflammation, tissue necrosis, and fistula formation. However, it is difficult to observe pancreatic leakage during surgery and to evaluate the protease activity of leaked fluid at the patient's bedside. This report describes a protein nanocage-based protease ratiometric sensor comprising a pancreatic protease-sensitive small heat-shock protein (HSP) 16.5, which is a naturally occurring protein in Methanococcus jannaschii that forms a spherical structure by self-assembly of 24 subunits, and a chemically conjugated donor-acceptor dye pair for Förster resonance energy transfer (FRET). The HSP-FRET probe was constructed by subunit exchange of each dye-labeled engineered HSP, resulting in a spherical nanocage of approximately 10 nm in diameter, which exhibited very high stability against degradation in blood plasma and no remarkable toxicity in mice. The efficiency of FRET was found to depend on both the dye orientation and the acceptor/donor ratio. Pancreatic proteases, including trypsin, α-chymotrypsin, and elastase, were quantitatively analyzed by fluorescence recovery with high specificity using the HSP-FRET nanoprobe. Furthermore, the HSP-FRET nanoprobe was sufficiently sensitive to detect POPF in the pancreatic juice of patients using only the naked eye within 10 min. Thus, this novel nanoprobe is proposed as an effective and convenient tool for the detection of POPF and the visualization of activated pancreatic juice during gastroenterological surgery.

Giant epidermoid cyst of the spleen with elevated CA 19-9 production managed laparoscopically: report of a case.

True splenic cysts are uncommon and are associated with elevated serum and intracystic tumor marker CA 19-9 levels. A 33-year-old woman presented to our hospital with a chief complaint of epigastralgia. Computed tomography of the abdomen showed a 10-cm cystic lesion in the spleen. The serum carbohydrate antigen (CA) 19-9 level was 3,347 U/mL (normal, <37 U/mL). Total laparoscopic splenectomy was performed, and the serum level of CA 19-9 had normalized 2 weeks later. Pathological examination showed a benign true epidermal cyst of the spleen with strong immunohistological staining for CA 19-9. Splenic epidermoid cysts most often occur in young women, and laparoscopic surgery to remove cysts of this type is minimally invasive. Thus, laparoscopic surgery should be the method of first choice for most cases of splenic benign true cyst.