Short-term outcomes of laparoscopic and robotic distal gastrectomy for gastric cancer: Real-world evidence from a large-scale inpatient database in Japan

BACKGROUND AND OBJECTIVES

Robotic distal gastrectomy (RDG) has been widely performed throughout Japan since it became insured in 2018. This study aimed to evaluate the short-term outcomes of RDG and laparoscopic distal gastrectomy (LDG) for gastric cancer using real-world data.

METHODS

A total of 4161 patients who underwent LDG (n = 3173) or RDG (n = 988) for gastric cancer between April 2018 and October 2022 were identified through the Japanese Diagnosis Procedure Combination Database, which covers 42 national university hospitals. The primary outcome was postoperative in-hospital mortality rate. The secondary outcomes were postoperative complication rates, time to diet resumption, and postoperative length of stay (LOS).

RESULTS

In-hospital mortality and postoperative complication rates in the RDG group were comparable with those in the LDG group (0.1% vs. 0.0%, p = 1.000, and 8.7% vs. 8.2%, p = 0.693, respectively). RDG was associated with a longer duration of anesthesia (325 vs. 262 min, p < 0.001), similar time to diet resumption (3 vs. 3 days, p < 0.001), and shorter postoperative LOS (10 vs. 11 days, p < 0.001) compared with LDG.

CONCLUSIONS

RDG was performed safely and provided shorter postoperative LOS, since it became covered by insurance in Japan.

Interleukin-6 Stromal Expression is Correlated with Epithelial-Mesenchymal Transition at Tumor Budding in Colorectal Cancer

Background. Tumor budding is a poor prognostic factor in colorectal adenocarcinoma, but the underlying mechanism remains unclear. Interleukin-6 (IL6) is one of the main cytokines produced by cancer-associated fibroblasts. IL6 is linked with cancer progression and poor prognosis by activating cancer cells and modifying the cancer microenvironment. However, little is known about the expression of IL6 in tumor budding and its association with tumor budding in colorectal adenocarcinoma. Methods. The clinicopathological and prognostic significance of IL6 in tumor budding was examined using a tissue microarray consisting of 36 patient samples of tumor budding in colorectal adenocarcinoma. IL6 mRNA was detected by RNAscope. Patients were stratified into negative and positive IL6 expression groups. Results. IL6 expression was overwhelmingly observed in cancer stroma but was negligible in cancer cells. Tumor budding grade was higher in the IL6-positive group in cancer stroma than in the IL6-negative group (P = .0161), while the IL6-positive group significantly exhibited the epithelial-mesenchymal transition phenotype compared with the IL6-negative group in cancer stroma (P = .0301). There was no significant difference in overall survival between colorectal adenocarcinoma patients in the IL6-positive and -negative groups in cancer stroma. Conclusion. Tumor budding may be affected by IL6 expression, and IL6 expression in cancer stroma at tumor budding may be an important prognostic marker.

Transmesenteric approach for laparoscopic endoscopic cooperative surgery for a duodenal adenoma located in the third portion of the duodenum

We report our experience in a patient with adenoma located in the horizontal part of the duodenum, which was effectively treated with the transmesenteric laparoscopic endoscopic cooperative surgery (LECS) approach. This approach, which entails incising the mesentery of the colon, simplified laparoscopic access to the horizontal part of the duodenum, which was minimally mobilized. Thus, the bulb and descending part of the duodenum were fixed to the retroperitoneum, facilitating stable handling of the endoscope and enabled safe and effective excision of an adenoma located in the horizontal part of the duodenum. This approach enabled safe and effective excision of an adenoma located in the horizontal part of the duodenum. The advantages of this method include a secure field of view, lower probability of damage to large vessels, and minimizing the defect to the intestine caused by the incision.

Cetuximab Enhances the Efficacy of MRTX1133, a Novel KRASG12D Inhibitor, in Colorectal Cancer Treatment

BACKGROUND/AIM

Kirsten Rat Sarcoma viral oncogene homolog (KRAS) has remained undruggable for decades. KRAS has predominantly been used to evaluate the applicability of anti-Epidermal Growth Factor Receptor (EGFR) antibody drugs. However, various KRAS inhibitors have recently emerged. Unfortunately, KRAS inhibitors have not been effective against colorectal cancer. Therefore, this study aimed to determine the effects of MRTX1133, a novel KRASG12D inhibitor, in combination with an anti-EGFR antibody, cetuximab, on signal transduction and cell proliferation.

MATERIALS AND METHODS

The KRASG12D-mutated LS513 and KRAS wild-type CACO-2 human colon cancer cell lines were utilized. The KRASG12D mutation was stably transduced into the CACO-2 cells using a retrovirus. We evaluated the effects of the drugs using the CCK-8 assay and assessed the activity of proteins related to the MAPK pathway using western blotting.

RESULTS

We demonstrated that the administration of MRTX1133, a novel KRASG12D inhibitor, to KRASG12D-mutated colorectal cancer cells led to feedback activation of the ERK pathway via EGFR activation, inducing drug resistance. Intriguingly, when MRTX1133 was used in combination with cetuximab, KRASG12D-mutant colorectal cancer growth was effectively inhibited, both in vitro and in vivo.

CONCLUSION

The combination of MRTX1133 and cetuximab serves as a potential and promising therapeutic approach for colorectal cancer with KRASG12D mutation. KRASG12D is a frequent genetic mutation not only in colorectal cancer, but also in pancreatic and lung cancer, and the results of this study open new avenues for potential treatment of many cancer patients.

Impact of Oophorectomy on Survival and Improving Nutritional Status in Ovarian Metastasis from Colorectal Adenocarcinoma

INTRODUCTION

Ovarian metastasis of colorectal cancer is known to have a poor prognosis. This study aimed to elucidate the characteristics of patients who underwent oophorectomy for ovarian metastasis from colorectal cancer.

METHODS

This retrospective study included 16 patients who underwent oophorectomy for colorectal cancer metastasis to the ovary from January 2004 to December 2017. Improvement in patient's symptoms and pre- and postoperative changes in various nutritional and inflammatory indicators were assessed. Survival analysis and identification of prognostic factors were conducted with a median follow-up of 40.7 (5-109) months.

RESULTS

Of 16 patients, 12 had (75%) synchronous and 4 (25%) had metachronous metastasis. Fourteen patients were symptomatic but symptoms resolved postoperatively. Thirteen patients (81.3%) had ascites and 5 (31.3%) had pleural effusion on preoperative computed tomography that disappeared after surgery in all cases. The median value of prognostic nutritional factor was significantly increased postoperatively (36.0 [preoperatively] vs. 47.5, p < 0.0001). The median (interquartile range) values for lymphocyte-C-reactive protein ratio were 715.2 (110-2,607) preoperatively and 6,095.2 (1,612.3-14,431.8) postoperatively (p = 0.0214). The median survival of the entire cohort was 60.4 months. The 3-year survival rates for R0 + R1 and R2 cases were 83% and 24% (p = 0.018), respectively. Univariate analysis showed that R2 resection and low postoperative lymphocyte-C-reactive protein ratio were associated with poor prognosis.

CONCLUSIONS

Oophorectomy for ovarian metastasis from colorectal cancers was safely performed. It improved the patients' symptoms and nutritional status and may result in improved prognosis.

Comparison of Short-term Outcomes Between Esophageal Bypass Surgery and Self-expanding Stent Insertion in Esophageal Cancer: A Propensity Score-matched Analysis Using a Large-scale Inpatient Database

BACKGROUND

Advanced esophageal cancer is occasionally accompanied by difficulty swallowing owing to esophageal stenosis or tracheoesophageal fistula formation. Esophageal bypass surgery and stent insertion are considered feasible palliative management options. The aim of this study was to evaluate the short-term outcomes of these palliative treatments.

MATERIALS AND METHODS

Patient data were obtained from a large-scale inpatient database of 42 National University Hospitals in Japan. Patients with advanced esophageal cancer who underwent esophageal bypass surgery or stent insertion between April 2016 and March 2021 were included in this study. One-to-one propensity score matching of patients who underwent bypass surgery or stent insertion was performed. The primary outcomes were time to diet resumption and length of hospital stay after surgery. The secondary outcome was the incidence of postoperative complications.

RESULTS

In 43 propensity score-matched pairs, the incidence of postoperative respiratory complications was significantly higher in the bypass group than in the stent group (32.6% vs. 9.3%, P = 0.008). Postoperative length of hospital stay was longer in the bypass group than in the stent group (24 vs. 10 d, P < 0.001). Logistic regression analysis revealed that stent insertion was associated with a decreased risk of respiratory complications (odds ratio 0.077, P < 0.007). Among patients who underwent the interventions (bypass surgery or stent insertion) and subsequently underwent anticancer therapy (chemotherapy/radiotherapy) during hospitalization, the interval between the intervention and anticancer therapy was longer in the bypass group than in the stent group (25 vs. 7 d, P = 0.003).

CONCLUSIONS

Esophageal stent insertion provides better short-term outcomes than bypass surgery in patients with advanced unresectable esophageal cancer.

MEK inhibitor and anti-EGFR antibody overcome sotorasib resistance signals and enhance its antitumor effect in colorectal cancer cells

The Kirsten rat sarcoma (KRAS) oncogene was "undruggable" until sotorasib, a KRAS^G12C selective inhibitor, was developed with promising efficacy. However, inhibition of mutant KRAS in colorectal cancer cells (CRC) is ineffective due to feedback activation of MEK/ERK downstream of KRAS. In this study, we screened for combination therapies of simultaneous inhibition to overcome sotorasib resistance using our previously developed Mix Culture Assay. We evaluated whether there was an additive effect of sotorasib administered alone and in combination with two or three drugs: trametinib, a MEK inhibitor, and cetuximab, an anti-epidermal growth factor receptor (EGFR) antibody. The MAPK pathway was reactivated in KRAS^G12C-mutated cell lines treated with sotorasib alone. Treatment with KRAS and MEK inhibitors suppressed the reactivation of the MAPK pathway, but upregulated EGFR expression. However, the addition of cetuximab to this combination suppressed EGFR reactivation. This three-drug combination therapy resulted in significant growth inhibition in vitro and in vivo. Our data suggest that reactive feedback may play a key role in the resistance signal in CRC. Simultaneously inhibiting KRAS, MEK, and EGFR is a potentially promising strategy for patients with KRAS^G12C-mutated CRC.

ARL4C is associated with epithelial-to-mesenchymal transition in colorectal cancer

BACKGROUND

ADP-ribosylation factor-like protein 4 C (ARL4C) is a member of the ARF small GTP-binding protein subfamily. The ARL4C gene is highly expressed in colorectal cancer (CRC). ARL4C protein promotes cell motility, invasion, and proliferation.

METHODS

We investigated the characteristics of ARL4C by comparing its expression at the invasion front and relationships with clinicopathological data using RNAscope, a highly sensitive RNA in situ method.

RESULTS

In all cases, ARL4C expression was observed in cancer stromal cells and cancer cells. ARL4C expression in cancer cells was localized at the invasion front. In cancer stromal cells, ARL4C expression was significantly stronger in cases with high-grade tumor budding than in cases with low-grade tumor budding (P = 0.0002). Additionally, ARL4C expression was significantly increased in patients with high histological grade compared with those with low histological grade (P = 0.0227). Furthermore, ARL4C expression was significantly stronger in lesions with the epithelial-to-mesenchymal transition (EMT) phenotype compared with the non-EMT phenotype (P = 0.0289). In CRC cells, ARL4C expression was significantly stronger in cells that had the EMT phenotype compared with those with a non-EMT phenotype (P = 0.0366). ARL4C expression was significantly higher in cancer stromal cells than in CRC cells (P < 0.0001).

CONCLUSION

Our analysis reinforces the possibility that ARL4C expression worsens the prognosis of patients with CRC. Further elucidation of the function of ARL4C is desired.

Goblet cell adenocarcinoma of the appendix: A case report of three cases

INTRODUCTION AND IMPORTANCE

Appendiceal goblet cell adenocarcinoma is in 0.3-0.9 % of appendectomy specimens. There is still controversy regarding whether surgery with dissection or additional resection is necessary for goblet cell adenocarcinoma and whether adjuvant chemotherapy is practical. We present three cases of goblet cell adenocarcinomas.

CASE PRESENTATION

Case 1: A 30-year-old woman was diagnosed with appendicitis and underwent appendicectomy. Histopathological evaluation revealed a malignant neoplasm with goblet-like cells and tumour infiltration into the subserosa. The patient underwent laparoscopic ileocecal resection, and the main lymph nodes at the root of the feeding vessels were removed. Case 2: A 50-year-old man was diagnosed with appendicitis and underwent appendicectomy. Histopathological evaluation revealed a malignant neoplasm with goblet-like cells; malignant cells were found at the surgical resection margins. The patient underwent laparoscopic ileocolic resection. Case 3: A 60-year-old man undergoing treatment for malignant melanoma. He was diagnosed with appendicitis associated with an appendiceal tumour, and emergency laparoscopic caecal resection was performed and diagnosed as goblet cell adenocarcinoma. We decided to prioritize treatment for malignant melanoma, and the patient is under follow-up for goblet cell adenocarcinoma and no metastasis was detected.

CLINICAL DISCUSSION

We performed additional resection in two case of goblet cell adenocarcinoma. Diagnosing appendiceal goblet cell adenocarcinoma is difficult, and the prognosis of patients with positive lymph nodes is poor. Surgical treatment should be considered for the advanced stages of this disease.

CONCLUSION

Goblet cell adenocarcinoma, diagnosed after appendectomy, additional resection including lymph node dissection may provide a long-term prognosis.

Importance of intraoperative indocyanine green imaging in the management of non-occlusive mesenteric ischemia: a case report

BACKGROUND

Non-obstructive intestinal ischemia (NOMI) is caused by intestinal vascular spasm and has a poor prognosis if not diagnosed and treated early. Indocyanine green (ICG) fluorescence imaging has been reported to be useful for the intraoperative assessment of the extent of intestinal resection required for NOMI. Few reports have described massive intestinal bleeding after conservative management of NOMI. We report a case of NOMI with massive postoperative bleeding from the site of an ICG contrast defect found before the initial surgery.

CASE PRESENTATION

A 47-year-old woman with hemodialysis-dependent chronic kidney disease presented complaining of severe abdominal pain. A computed tomography scan showed portal gas and dilation of the small intestine, leading to a diagnosis of NOMI and subsequent emergency surgery. At the time of initial surgery, the contrast effect of ICG was slightly reduced, showing a granular distribution in the ascending colon to cecum (fine grain pattern) and significantly reduced in parts of the terminal ileum except around blood vessels (perivascular pattern). However, there was no obvious gross necrosis of the serosal surface, and the intestinal tract was not resected. The acute postoperative course was uneventful; however, the patient went into shock on the 24th postoperative day due to massive, small intestinal bleeding, and emergency surgery was performed. The bleeding originated from the section of the ileum that had complete loss of ICG contrast effect before the initial surgery. A right hemicolectomy with the terminal ileum resection was performed, and an ileo-transverse anastomosis was performed. The second post-operative course was uneventful.

CONCLUSIONS

We report a case of delayed hemorrhage of the ileum shown to have poor blood flow on ICG imaging at the initial surgery. Intraoperative ICG fluorescence imaging is useful in assessing the degree of intestinal ischemia for NOMI. When patients with NOMI are followed up without surgery, complications such as bleeding should be noted.

Hereditary diffuse gastric cancer in a Japanese family with CDH1 mutation three case reports

BACKGROUND

Germline pathogenic variants in the E-cadherin gene CDH1 cause hereditary diffuse gastric cancer (HDGC), which is an autosomal dominant cancer syndrome, accounting for 1-3% of all gastric cancers. HDGC harboring a CDH 1 variant is extremely rare in Japan.

METHOD

In this study we report the clinical courses of three cases with HDGC from a single Japanese family.

RESULTS

The proband exhibited advanced and metastatic gastric cancer, and was found to have a previously reported heterozygous frameshift variant in CDH1 (NM_004360.3:c.1009_1010del:p.Ser337Phefs*12). Five at-risk relatives underwent presymptomatic molecular testing after careful genetic counseling, and three were molecularly diagnosed as positive for the variant. Esophagogastroduodenoscopy was performed in these relatives revealing abnormal small pale mucosal patches, small ulcerative lesion and no abnormal findings. Moreover, random and targeted biopsies were compatible with pathological diagnosis of HDGC in the three cases, all of which underwent total prophylactic gastrectomy.

CONCLUSION

It is critical for the assessment and management of HDGC patients to be actively offered a multidisciplinary and familial-oriented approach. Notably, genetic screening in suspected individuals and familial members is a determining piece for a higher detection rate and the identification of clinical relevant mutations in both low and high-incidence gastric cancer countries.

RhoA G17E/Vav1 Signaling Induces Cancer Invasion via Matrix Metalloproteinase-9 in Gastric Cancer

BACKGROUND

RAS homolog family member A (RhoA), a member of the Rho family of small GTPases, and Vav1, a guanine nucleotide exchange factor for Rho family GTPases, have been reported to activate pathways related to the actin cytoskeleton and regulation of cell shape, attachment, and motility. The interaction between these molecules in lymphoma is involved in malignant signaling, but its function in epithelial malignancy is unknown. Here, we investigated the malignant signal of mutant RhoA in gastric cancer and demonstrated the potential of RhoA G17E/Vav1 as a therapeutic target for diffuse gastric cancer.

METHODS

The RhoA mutants R5W, G17E, and Y42C were retrovirally transduced into the gastric cancer cell line MKN74. The stably transduced cells were used for morphology, proliferation, and migration/invasion assays in vitro. MKN74 cells stably transduced with ectopic wild-type RhoA and mutant RhoA (G17E) were used in a peritoneal xenograft assay.

RESULTS

The RhoA mutations G17E and Y42C induced morphological changes in MKN74. G17E induced Vav1 expression at the mRNA and protein levels and promoted the migration and invasion of MKN74. An RNA interference assay of Vav1 revealed that RhoA G17E enhanced cancer cell invasion via Vav1. Furthermore, immunoprecipitation revealed that Vav1 and RhoA G17E specifically bind and function together through matrix metalloproteinase -9. In a peritoneal xenograft model of nude mice, RhoA G17E promoted peritoneal dissemination, whereas Vav1 knockdown suppressed it.

CONCLUSION

Overall, our findings indicate that RhoA G17E is associated with Vav1 and promoted cancer invasion via matrix metalloproteinase -9 in gastric cancer cells. Thus, RhoA G17E/Vav1 signaling in diffuse gastric cancer may be a useful therapeutic target.

Gastric glomus tumor resection using laparoscopic endoscopic cooperative surgery: A case report

Gastric glomus tumors are rare submucosal mesenchymal neoplasms that are difficult to diagnose preoperatively. We present a case of a 60-year-old woman who was diagnosed with a gastric glomus tumor using endoscopic ultrasonography-guided fine-needle aspiration biopsy. The tumor was successfully resected with laparoscopic endoscopic cooperative surgery (LECS). LECS could be an effective method for the resection of gastric glomus tumors.

Risk factors for umbilical incisional hernia after laparoscopic colorectal surgery

BACKGROUND

Laparoscopic colorectal surgery (LCRS) requires a small laparotomy at the umbilicus. The wound is small and inconspicuous, but if the patient develops an umbilical incisional hernia (UIH), the wound is visible and the patient suffers from symptoms of discomfort. However, the incidence of UIH after LCRS and its risk factors are not well understood. The purpose of this study was to investigate the risk factors for UIH after LCRS for colorectal cancer.

METHODS

This was a single-centre retrospective study of 135 patients with colorectal cancer, conducted at our hospital from April 2013 to March 2019. The diagnosis of UIH was based on computed tomography and physical examination findings. Preoperative patient data such as enlargement of the umbilical orifice (EUO), subcutaneous fat thickness (SFT) and intraperitoneal thickness (IPT) were collected and analysed using univariate and multivariate analyses for the presence of risk factors for UIH.

RESULTS

A total of 135 patients who underwent LCRS were analysed. The incidence of UIH was 20.7%. Univariate analysis revealed significantly high body mass index (BMI) ≥ 25 (P = 0.032), EUO (P < 0.001), SFT ≥18 mm (P = 0.011), and IPT ≥61 mm (P < 0.01) in the UIH group. Multivariate analysis revealed significant differences in EUO (P < 0.001), SFT ≥18 mm (P = 0.046) and IPT ≥61 mm (P = 0.022).

CONCLUSION

EUO was the most important risk factor for UIH, followed by IPT and SFT. These findings are predictive indicators of the development of UIH after LCRS and can be assessed objectively and easily with preoperative computed tomography.

Intraoperative visualization of morphological patterns of the thoracic duct by subcutaneous inguinal injection of indocyanine green in esophagectomy for esophageal cancer

To prevent chylothorax after esophageal cancer surgery, it is important to recognize morphological patterns of the thoracic duct intraoperatively. The present study aimed to evaluate the safety and usefulness of near-infrared (NIR) fluorescence imaging with subcutaneous inguinal injection of indocyanine green (SII-ICG) to detect the thoracic duct during thoracoscopic esophagectomy for esophageal cancer. Patients (n = 16) who underwent thoracoscopic esophagectomy in the prone position with SII-ICG at Shinshu University Hospital between June 2020 and January 2022 were enrolled in the present study and retrospectively reviewed. Immediately prior to thoracoscopic esophagectomy, we injected 0.2-0.5 mg/kg ICG into the subcutaneous tissue in the bilateral inguinal region. The identification rate of the thoracic duct was 93.8% (n = 15), and the success rate of fluorescence using SII-ICG was 87.5% (n = 14). The visible thoracic ducts had four patterns: a typical pattern in 50% (n = 8), duplication pattern in 18.8% (n = 3), branching pattern in 12.5% (n = 2), and plexiform pattern in 12.5% (n = 2). In all cases, ICG fluorescence did not disappear and was visible during the thoracic surgery. No SII-ICG-related complications were observed. Intraoperative NIR fluorescence imaging of the thoracic duct using SII-ICG is a simple and safe method with very high detection sensitivity. This method can be a powerful tool for avoiding thoracic duct injuries during esophageal cancer surgery.

Comparison of Clinical Outcomes and Safety Between Open and Laparoscopic Surgery for Adhesive Small Bowel Obstruction: A Propensity-Matched Analysis of a National Inpatient Database

Background: The effectiveness of laparoscopic surgery for adhesive small bowel obstruction (ASBO) remains unclear. We aimed to compare the outcomes and safety of open and laparoscopic surgeries for ASBO. Methods: In this retrospective study, we analyzed an inpatient database of 42 national university hospitals in Japan. Patients who underwent surgery for the first episode of ASBO between April 2013 and March 2018 were identified. Using the propensity score method, patients who underwent laparoscopic surgery were matched one-to-one with those who underwent open surgery. We investigated postoperative clinical outcomes, including morbidity, mortality, length of hospital stay (LOS), and recurrence. Results: Overall, 306 and 96 patients underwent open and laparoscopic surgery, respectively (96 propensity score-matched pairs). The incidence rates of postoperative morbidity, mortality, and recurrence were comparable between the two groups. Cox regression analysis revealed a hazard ratio (HR) of 1.020 (P = .959) for readmission due to ASBO in the laparoscopic surgery group relative to the open surgery group. Postoperative hospital stay was longer for open surgery than for laparoscopic surgery (13.0 days versus 10.0 days, P < .001). Cox regression analysis revealed that laparoscopic surgery was associated with earlier postoperative discharge compared with open surgery (HR 1.641, P = .002). Conclusions: The postoperative LOS was shorter with laparoscopic surgery than with open surgery for ASBO, but there were no differences between the procedures in other clinical outcomes. Laparoscopic surgery is suitable to treat patients with ASBO.

Association of Daily Variance in Air Temperature With Postoperative Adhesive Small Bowel Obstruction

Introduction: The influence of air temperature on adhesive small bowel obstruction (ASBO) is unknown. This study aimed to investigate the relationship between air temperature and postoperative ASBO.

Methods: Overall, 312 patients with postoperative ASBO were included. They were categorized into two groups: the surgery group (n = 83) comprising patients who needed surgery, and the non-surgery group (n = 229) comprising patients who responded to conservative treatment. The associations between patients’ characteristics and weather variables on days of symptom onset with the need for surgical management were investigated. Weather variables included the daily mean barometric pressure, daily mean air temperature, day-to-day differences, daily variances, and diurnal variation in the air temperature. Day-to-day differences in weather variables were calculated as the daily mean variables on the day of symptom onset minus those on the previous day. The daily variances in weather variables were defined as the absolute value of day-to-day differences.

Results: Compared to the non-surgery group, the surgery group had older patients (75 vs. 70 years, p = 0.009), a higher proportion of female patients (44.6% vs. 32.3%, p = 0.046), increased incidence of closed-loop sign (50.6% vs. 0.9%, p < 0.001), a lower proportion of feces sign (18.1% vs. 31.3%, p = 0.024), and a prolonged hospital stay (11 vs. 22 days, p < 0.001). The number distribution of patients in the surgery group in day-to-day differences in air temperature was different from that of the non-surgery group; the former has several peaks whereas the latter has almost one peak. Daily variance in mean air temperature on the day of symptom onset was higher in the surgery group than in the non-surgery group (2.3 vs. 1.3℃, p < 0.001). Multiple logistic regression analysis revealed that increased daily variance in air temperature on the onset day was associated with the need for surgical management (odds ratio 1.254, p = 0.002) and closed-loop obstruction (odds ratio 1.235, p = 0.017). Regarding seasonal variations, the risk of the need for surgery and closed-loop obstruction in each ASBO patient was the highest in spring, followed by that in summer, autumn, and winter. Consistently, the daily variance in mean air temperature in spring was higher than that in summer, autumn, and winter (p < 0.0001, p < 0.0001, and p = 0.0047, respectively). The risk of the need for surgery and closed-loop obstruction in each ASBO patient was the highest in spring, followed by that in summer, autumn, and winter. Consistently, daily variance in mean air temperature was higher in spring than that in summer, autumn, and winter (p < 0.0001, p < 0.0001, and p = 0.0047, respectively).

Conclusion: Increased daily variance in mean air temperature on the day of onset is associated with the need for surgical management and closed-loop obstruction. Spring is characterized by the highest daily variance in mean air temperature among the four seasons, and is associated with high proportions of the need for surgery and closed-loop obstruction. These results can be clinically useful in terms of hospital resource reallocation and staffing, and can help clarify the pathogenesis of ASBO.

Laparoscopic left-sided mesocolic leaf flap repair for pelvic reconstruction after sacral tissue necrosis. A case report

Radical surgical procedures for malignant diseases of the pelvis result in a large pelvic defect that requires soft tissue reconstruction. The mesentery can be used for pelvic floor reconstruction when debridement with intestinal resection is required. A 75-year-old woman was diagnosed with sacral necrosis, infection and sepsis after carbon ion radiotherapy for sacral chordoma. She underwent sacral debridement three times, which resulted in a large pelvic defect of 14 × 13 cm. Surgery was performed to completely resect the necrotic tissue. We performed extended debridement of sacrum and adjacent tissue around the rectum and anus. Since it was impossible to preserve the anus, laparoscopic left hemicolectomy, abdominosacral resection, and left-sided mesocolic leaf repair for the pelvic defect, and reconstructed the pelvis and buttocks using a gluteal thigh flap were performed. Indocyanine green fluorescent (ICG) imaging was used to detect the margin of the pelvic floor and necrotic tissue and the blood flow of the left-sided mesocolic leaf flap. Left-sided mesocolic leaf reconstruction is useful for large pelvic defects. ICG imaging enabled the detection of the resection margins and the blood flow of the mesocolic leaf.

Impact of seasonal and meteorological factors on the incidence of adhesive small bowel obstruction: A large‐scale study using a national inpatient database

Aim

Whether seasonal and meteorological factors affect the incidence of adhesive small bowel obstruction (ASBO) remains unclear. This study aimed to clarify the impacts of seasonal and meteorological factors on the occurrence of ASBO.

Methods

Clinical data of patients with ASBO were acquired from 42 national university hospitals in Japan, using a national inpatient database, between April 2012 and March 2020. Meteorological data were obtained from the Japan Meteorological Agency. The number of monthly admissions of patients with ASBO was compared between each of the 12 months. Daily weather variables were investigated to clarify their association with ASBO patient admissions on a total of 119 802 days (Formula for calculation: study period [2922 days] ×41 cities).

Results

Overall, 4985 patients with ASBO were admitted. The number of admissions in June was smaller than that in October, November, and December (39 vs 63.5, P = .002, 39 vs 65, P = .004, and 39 vs 59.5, P = .002, respectively). Logistic regression analysis revealed that January, October, November, and December were associated with increased risk of admission compared to June (odds ratio [OR], 1.264; P = .001; OR, 1.454; P < .001; OR, 1.408; P < .001; OR, 1.330; P < .001), respectively. Regarding the weather variables, higher barometric pressure and lower humidity were associated with increased risk of admission (OR, 1.011; P < .001 and OR, 0.995; P < .001), respectively.

Conclusion

The incidence of ASBO is susceptible to barometric pressure and humidity and varies monthly. These results can contribute to the prevention, early detection, and immediate and appropriate management of ASBO.

A case of appendiceal ganglioneuroma in neurofibromatosis type 1

BACKGROUND

Neurofibromatosis type 1 is an autosomal dominant inherited disease associated with multiple skin neurofibromas or other neurogenic tumors, such as nodular plexiform neurinoma or cerebrospinal tumor. Gastrointestinal stromal tumors are often complicated in patients with neurofibromatosis type 1, although involvement of the appendix is rare, and there have been few reports of appendiceal ganglioneuroma.

CASE PRESENTATION

The patient was a 29-year-old man diagnosed with neurofibromatosis type 1 based on physical findings and his family history. During the follow-up of neurofibromatosis, computed tomography was performed to detect neurological tumors, such as neurofibromas in the brain, spinal cord, and gastrointestinal tract. Computed tomography showed a markedly thickened appendix wall, and an appendiceal tumor was suspected. Laparoscopic appendectomy was performed, and a 50 × 35 mm appendiceal submucosal tumor was resected with a negative resection margin. At histopathological examination, the tumor was diagnosed as ganglioneuroma; it showed short spindle-shaped cells and ganglion cells diffusely infiltrated into the proper muscle layer and fibrous tissue that grew around nerve cells. The patient was discharged on the 5th postoperative day without postoperative complications and was doing well at 13 months following the operation.

CONCLUSIONS

Gastrointestinal stromal tumor and neurofibroma are the most common gastrointestinal tumors associated with neurofibromatosis type 1, but ganglioneuroma of the appendix is rare. Appendiceal neurogenic tumors should be considered in patients with neurofibromatosis type 1, and surgical resection is necessary because of the risk of malignancy.

Sex differences in non-strangulated postoperative adhesive small bowel obstruction: A retrospective cohort study

BACKGROUND

Adhesive small bowel obstruction (ASBO) is one of the major causes of postoperative morbidity. Non-surgical management is generally applied to non-strangulated ASBO. Several factors have been reported to affect the response to non-surgical management in patients with ASBO. However, the association between sex differences and non-strangulated ASBO remains unclear. This study aimed to elucidate the effect of sex differences in non-strangulated postoperative ASBO.

METHODS

We divided 139 patients with a first episode of non-strangulated postoperative ASBO into two groups: male group (n = 83) and female group (n = 56). Clinical features and prognosis were compared between the two groups.

RESULTS

Female patients had lower proportions of oesophageal/gastric malignancies (P = 0.044) and colorectal malignancies (P = 0.030) and a higher proportion of uterine/ovarian malignancies (P < 0.001) than male patients did. More female patients required surgical management than male patients (P = 0.003) did. Hospital length of stay (LOS) was longer (P = 0.046) in the female group than in the male group. Multiple logistic regression analysis showed that the female sex was associated with an increased risk of the need for surgical management (odds ratio 5.318, P = 0.006). Cox proportional hazards regression analysis revealed that the female sex was positively associated with increased LOS (hazard ratio 0.687, P = 0.045).

CONCLUSION

Female sex was associated with failure of non-surgical management and increased LOS in patients with non-strangulated postoperative ASBO.

Lymphocyte-to-Monocyte Ratio Is a Predictive Biomarker of Response to Treatment with Nivolumab for Gastric Cancer

INTRODUCTION

Patients with unresectable or recurrent gastric cancer who have an objective response (OR) to nivolumab monotherapy are expected to have a good long-term prognosis. However, the OR rate for nivolumab treatment is low at 11%, and there is a need for biomarkers to predict the treatment response. This study aimed to analyze the significance of systemic inflammation-related variables and clinicopathologic characteristics as predictive markers of response to nivolumab monotherapy in patients with advanced gastric cancer.

METHODS

In this retrospective cohort study, we enrolled 71 consecutive patients who received nivolumab monotherapy for unresectable or recurrent gastric cancer. Receiver operating characteristic curve analysis was performed to determine the cutoff values of systemic inflammation-related variables, predictors of treatment response, and other prognostic factors related to nivolumab therapy. We focused on systemic inflammation-related variables measured before nivolumab induction and 2 weeks after its first administration and performed multivariate analysis to assess whether they could be used as prognostic factors.

RESULTS

Multivariate analysis revealed that a lymphocyte-to-monocyte ratio (LMR) of ≤3.28 after 2 weeks of initial nivolumab treatment (2wLMR) is a statistically significant predictor of treatment response (p = 0.012). The progression-free survival (PFS) rate of patients with liver metastasis was significantly worse than that of the other patients (1-year PFS: 0.0 vs. 24.4%, respectively; p = 0.005). The overall survival (OS) of patients with a low 2wLMR was significantly longer than that in patients with a high 2wLMR (1-year OS: 37.4 vs. 18.9%, respectively; p = 0.022).

CONCLUSIONS

Thus, the 2wLMR could be a useful biomarker to predict response to nivolumab treatment and the prognosis of unresectable and recurrent gastric cancer.

Laparoscopic abdominosacral resection for rectal and anal canal carcinoma with pagetoid spread

INTRODUCTION

Perianal Paget's disease is associated with adenocarcinoma and can spread to the perianal skin. It often requires extensive resection of the perianal skin and rectum. Many studies have shown the efficacy of laparoscopic abdominoperineal resection for lower rectal cancer. However, extensive resection of the dorsal side of the perineal skin is difficult in the lithotomy position. We report a laparoscopic abdominosacral approach using the jackknife position for perianal Paget's disease.

MATERIALS AND SURGICAL TECHNIQUE

Surgery was started using the lithotomy position, and total mesorectal excision with central lymphadenectomy was performed laparoscopically. Pelvic floor muscles were divided 2 cm away from the rectum. The sigmoid colon was then divided with a linear stapler, and a terminal colostomy was made. The sacral approach was then followed with the patient placed in a jackknife position. A skin incision was made 1-2 cm from the negative margin confirmed by preoperative mapping biopsy and resected en-bloc. We used this approach in two patients with a mean operative time of 483 minutes, including 53.5 minutes for the position change. All tumor margins, including the skin, were cancer-free, and primary wound closure was possible in both of the cases. Both patients were doing well without any recurrence 10 and 13 months postoperatively.

CONCLUSION

Laparoscopic abdominosacral resection is safe and effective and facilitates extensive perineal skin resection, especially on the dorsal side, with a less invasive laparoscopic procedure.

Drug sensitivity profile of minor KRAS mutations in colorectal cancer using mix culture assay: The effect of AMG-510, a novel KRAS G12C selective inhibitor, on colon cancer cells is markedly enhanced by the combined inhibition of MEK and BCL-XL

Colorectal cancer with a Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) gene mutation is considered to be resistant to anti-EGFR agents. G12D is the most common KRAS mutation in colorectal cancer, followed by G12V and G13D. According to clinical and basic research data, patients with colorectal cancer exhibiting G12D and G12V KRAS mutations are resistant to anti-EGFR agents; however, this is not true of G13D and other minor mutations, which are still not well understood. The current study focused on minor KRAS mutations (G12A, G12C, G12S, Q61H and A146T) and evaluated whether these were resistant to anti-EGFR antibodies using a mix culture assay. The results demonstrated that all KRAS mutations, including minor mutations, were resistant to two anti-EGFR agents: Cetuximab and panitumumab. The combined effect of MEK and BCL-XL inhibition on colorectal cancer cells with KRAS minor mutations were subsequently evaluated. The combined effect of MEK and BCL-XL inhibitors was confirmed in all KRAS minor mutations. The sensitivity of AMG510, a novel KRAS G12C selective inhibitor, was also assessed. The mix culture assay revealed that AMG510 selectively exerted an antitumor effect on colon cancer cells with a G12C KRAS mutation. The combination of MEK and BCL-XL inhibition markedly enhanced the effect of AMG510 in colon cancer cells. The current study suggested that AMG510 may have potential clinical use in combination with MEK and BCL-XL inhibitors in the treatment of patients with colorectal cancer exhibiting the G12C KRAS mutation.

Low‑dose trametinib and Bcl‑xL antagonist have a specific antitumor effect in KRAS‑mutated colorectal cancer cells

KRAS‑mutant colorectal cancer (CRC) is a highly malignant cancer with a poor prognosis, however specific therapies targeting KRAS mutations do not yet exist. Anti‑epidermal growth factor receptor (EGFR) agents, including cetuximab and panitumumab, are effective for the treatment of certain patients with CRC. However, these anti‑EGFR treatments have no effect on KRAS‑mutant CRC. Therefore, new therapeutic strategies targeting KRAS‑mutant CRC are urgently needed. To clarify the direct effect of KRAS gene mutations, the present study transduced mutant forms of the KRAS gene (G12D, G12V and G13D) into CACO‑2 cells. A drug‑screening system (Mix Culture assay) was then applied, revealing that the cells were most sensitive to the MEK inhibitor trametinib among tested drugs, Cetuximab, Panitumumab, Regorafenib, Vemurafenib, BEZ‑235 and Palbociclib. Trametinib suppressed phosphorylated ERK (p‑ERK) expression and inhibited the proliferation of KRAS‑mutant CACO‑2 cells. However, low‑dose treatment with trametinib also increased the expression of the anti‑apoptotic protein Bcl‑xL in a dose‑dependent manner, leading to drug resistance. To overcome the resistance of KRAS‑mutant CRC to apoptosis, the combination of trametinib and the Bcl‑xL antagonist ABT263 was assessed by in vitro and in vivo experiments. Compared with the effects of low‑dose trametinib monotherapy, combination treatment with ABT263 had a synergistic effect on apoptosis in mutant KRAS transductants in vitro. Furthermore, in vivo combination therapy using low‑dose trametinib and ABT263 against a KRAS‑mutant (G12V) xenograft synergistically suppressed growth, with an increase in apoptosis compared with the effects of trametinib monotherapy. These data suggest that a low dose of trametinib (10 nM), rather than the usual dose of 100 nM, in combination with ABT263 can overcome the resistance to apoptosis induced by Bcl‑xL expression, which occurs concurrently with p‑ERK suppression in KRAS‑mutant cells. This strategy may represent a promising new approach for treating KRAS‑mutant CRC.

Impact of barometric pressure on adhesive small bowel obstruction: a retrospective study

Background

Adhesive small bowel obstruction (ASBO) is one of the most common causes of postoperative morbidity. According to Boyle’s law, decreased barometric pressure expands the volume of intestinal gas. We aimed to elucidate the relationship between barometric pressure and ASBO.

Methods

We divided 215 admissions of 120 patients with ASBO into three groups: the fasting group, which responded to fasting (n = 51); the decompression group, which was successfully treated with gastrointestinal decompression (n = 104); and the surgery group which required emergency or elective surgery to treat ASBO (n = 60). We compared and examined clinical backgrounds, findings on admission, and barometric pressure during the peri-onset period (29 days: from 14 days before to 14 days after the onset of ASBO).

Results

There were significant differences among the three groups regarding gender, history of ASBO, hospital length of stay, and barometric pressure on the onset day of ASBO. Barometric pressure on the onset day was significantly higher in the fasting group than in the decompression group (p = 0.005). During pre-onset day 5 to post-onset day 2, fluctuations in the barometric pressure in the fasting and decompression groups showed reciprocal changes with a symmetrical axis overlapping the median barometric pressure in Matsumoto City; the fluctuations tapered over time after onset. In the fasting group, the barometric pressure on the onset day was significantly higher than that on pre-onset days 14, 11, 7, 4, 3, and 2; post-onset days 3 and 10; and the median pressure in Matsumoto City. Conversely, in the decompression group, the barometric pressure on the onset day was lower than that on pre-onset days 14, 5–2; post-onset days 1, 2, 7, 8, 11, 13, and 14; and the median pressure in Matsumoto City. In the surgery group, the barometric pressure on the onset day was equivalent to those on the other days.

Conclusions

ASBO with response to conservative treatment is vulnerable to barometric pressure. Additionally, ASBO that is successfully treated with fasting and decompression is associated with a different barometric pressure on the onset day and reciprocal fluctuations in the barometric pressure during the peri-onset period.

Types and site distributions of intestinal injuries in seat belt syndrome

OBJECTIVE

Intestinal injuries in seat belt syndrome are relatively uncommon but can be potentially lethal due to accompanying peritonitis and hemorrhaging. It can be difficult to identify the exact injury sites of the intestine as multiple areas are often damaged and massive intraperitoneal hemorrhaging may make it challenging to determine causal bleeding points of mesenteric injuries. This study aimed to clarify the incidence and distribution of intestinal injuries in seat belt syndrome.

METHODS

We retrospectively reviewed the clinical records of 25 patients who underwent laparotomy for suspected intestinal injuries due to seat belt syndrome during a frontal impact. The incidence and distribution of the sites of intestinal injuries, as well as associated injuries, were investigated. Intestinal injuries were divided into bowel and mesenteric injuries. Additionally, bowel injuries were classified into two types: perforation and non-perforation (seromuscular tears/intramural hematomas). Regarding the injured sites, the small intestine was divided into the following three parts: (1) the ligament of Treitz (100-cm distal from the ligament [proximal jejunum]), (2) the ileocecal valve (100-cm proximal from the valve [distal ileum]), and (3) the intermediate area between those two regions (jejunoileal junction).

RESULTS

In total, there were 64 major injuries among 25 patients requiring surgical intervention: 34 bowel injuries (20 perforations and 14 non-perforations) and 30 mesenteric injuries. Significantly more bowel perforations occurred in the small intestine (1 [interquartile range (IQR), 0-1]) than in the large intestine (0 [IQR, 0-0]) (p = 0.003). Similarly, significantly more mesenteric injuries occurred in the small intestine (1 [IQR, 0-1.25]) than in the large intestine (0 [IQR, 0-0]) (p < 0.001). Specific sites of the mesenteric injuries in the small intestine included the jejunoileal junction (0 [IQR, 0-1]) and distal ileum (0 [IQR, 0-1]); the jejunoileal junction was significantly more vulnerable than the proximal jejunum (0 [IQR, 0-0]) (p = 0.015).

CONCLUSIONS

In patients with seat belt syndrome, the small intestine was more vulnerable to perforation and mesenteric injury than the large intestine. Additionally, for mesenteric injuries, the jejunoileal junction was more likely to be damaged than the proximal jejunum.

Three Curative Pancreatectomies for the Metachronous Appearance of Pancreatic Invasive Ductal Adenocarcinoma

We report a rare case of a patient who underwent 3 successful curative operations for the metachronous appearance of pancreatic cancer. In July 2007, a 54-year-old woman underwent pylorus-preserving pancreaticoduodenectomy. In March 2010, a tumor measuring 9 mm in diameter was detected in the tail of the pancreas on computed tomography (CT) and magnetic resonance imaging. The pancreas tail was subsequently resected while preserving the pancreatic body. In February 2011, CT revealed a cystic tumor measuring 2.5 cm in diameter in the remnant pancreatic body without any metastasis; therefore, total resection of the residual pancreas was performed in April 2011. The first resected tumor was histopathologically diagnosed as undifferentiated adenocarcinoma with osteoclast-like giant cells. Additionally, the third resected tumor had similar undifferentiated components. Contrarily, the second resected tumor was diagnosed as a well-differentiated tubular adenocarcinoma. We consider that the tumor from the third operation was an intra-pancreatic metastasis of the primary cancer and that the tumor from the second operation was the second primary cancer. The patient responded well with good control of surgical diabetes for 92 months since the last pancreatectomy. This case suggested that aggressive repeated resection for recurrent pancreatic invasive ductal adenocarcinoma is beneficial in limited cases.

Treatment of Rectal Cancer-Induced Disseminated Carcinomatosis of the Bone Marrow with FOLFOX plus Cetuximab and Panitumumab

Disseminated carcinomatosis of the bone marrow (DCBM) in colorectal cancer is an extremely rare complication with a poor prognosis. Here, we report a case of DCBM due to rectal cancer successfully treated with a combination of FOLFOX and an anti-epidermal growth factor receptor (EGFR) agent. The patient was a 38-year-old man diagnosed with rectal cancer with multiple bone and para-aortic lymph node metastases complicated by disseminated intravascular coagulation (DIC). He first recovered from DIC following cotreatment with FOLOX plus cetuximab; subsequently, the second attack was successfully treated with FOLFOX plus panitumumab. His initial condition was extremely poor, but he survived with two FOLFOX plus anti-EGFR regimens and died 333 days after introduction of chemotherapy.

Fascin1 suppresses RIG-I-like receptor signaling and interferon-β production by associating with IκB kinase ϵ (IKKϵ) in colon cancer

Fascin1 is an actin-bundling protein involved in cancer cell migration and has recently been shown also to have roles in virus-mediated immune cell responses. Because viral infection has been shown to activate immune cells and to induce interferon-β expression in human cancer cells, we evaluated the effects of fascin1 on virus-dependent signaling via the membrane- and actin-associated protein RIG-I (retinoic acid-inducible gene I) in colon cancer cells. We knocked down fascin1 expression with shRNA retrovirally transduced into a DLD-1 colon cancer and L929 fibroblast-like cell lines and used luciferase reporter assays and co-immunoprecipitation to identify fascin1 targets. We found that intracellular poly(I·C) transfection to mimic viral infection enhances the RIG-I/MDA5 (melanoma differentiation-associated gene 5)-mediated dimerization of interferon regulatory factor 3 (IRF-3). The transfection also significantly increased the expression levels of IRF-7, interferon-β, and interferon-inducible cytokine IP-10 in fascin1-deleted cells compared with controls while significantly suppressing cell growth, migration, and invasion. We also found that fascin1 constitutively interacts with IκB kinase ϵ (IKKϵ) in the RIG-I signaling pathway. In summary, we have identified fascin1 as a suppressor of the RIG-I signaling pathway associating with IκB kinase ϵ in DLD-1 colon cancer cells to suppress immune responses to viral infection.

High incidence of other primary malignancies in patients with synchronous multiple gastric cancers "a multi-center retrospective cohort study"

This study evaluated the relationship between synchronous multiple gastric cancer and other primary malignancies. During 2002–2013, 1094 consecutive surgically treated gastric cancer patients were enrolled. Preoperatively, we performed total colonoscopy and whole-body computed tomography. When malignancies in other organs were suspected, detailed organ-specific examinations were performed. Synchronous multiple gastric cancer occurred in 102 patients (9.3%)which was frequently observed in patients with preoperative other primary malignancies (p < 0.001). Preoperative other primary malignancy was an independent risk factor for synchronous multiple gastric cancer (p = 0.001; hazard ratio: 2.145, 95% confidence interval: 1.354–3.399) and an independent prognostic factor of overall survival in patients undergoing gastrectomy with curative intent (p = 0.021; hazard ratio: 1.481, 95% confidence interval: 1.060–2.070). Thus, patients with preoperative other primary malignancies have a high risk of synchronous multiple gastric cancer. Careful preoperative examination is recommended to improve survival.

Survival pathway of cholangiocarcinoma via AKT/mTOR signaling to escape RAF/MEK/ERK pathway inhibition by sorafenib

Cholangiocarcinoma (CCC) is a strongly aggressive malignancy for which surgical resection is the only potential curative therapy. Sorafenib, a multikinase inhibitor of the RAF/MEK/ERK pathway, is a molecular-targeted drug that is approved for hepatocellular carcinoma (HCC) but not for CCC. The differences in signaling pathway characteristics under sorafenib treatment between HCC (HLF, Huh7, PLC/PRF/5) and CCC (RBE, YSCCC, Huh28) cell lines were therefore investigated using cell proliferation, western blotting, and apoptosis analyses. Sorafenib inhibited cell growth significantly less in CCC cells than in HCC cells, with lower suppression of ERK phosphorylation. Significantly decreased AKT Ser473 phosphorylation in HCC cells, and conversely enhanced phosphorylation of AKT Ser473 and mTORC2 in CCC cells, were observed with sorafenib treatment. Disassembly of the mTORC2 complex in RBE cells with siRNA targeting Rictor resulted in the downregulation of AKT Ser473 phosphorylation and enhanced apoptosis presumably via increased FOXO1, which consequently suppressed RBE cell proliferation. Phosphorylation of mTORC1 and autophagy were not influenced by sorafenib in CCC cells. Simultaneous administration of everolimus to suppress activated mTORC1 in RBE cells revealed that combined everolimus and sorafenib treatment under mTORC2 disassembly could enhance growth inhibition through the suppression of both sorafenib- and everolimus-dependent AKT Ser473 phosphorylation in addition to the inhibition of mTORC1 phosphorylation. Prevention of escape by AKT/mTOR signaling from the RAF/MEK/ERK pathway in sorafenib treatment by suppressing mTORC2 activity may lead to promising new approaches in CCC therapy.

Three Cases of Pseudo-Meigs' Syndrome Secondary to Ovarian Metastases from Colorectal Cancer

Pseudo-Meigs' syndrome is used to describe cases of ascites and/or pleural effusion associated with ovarian neoplasms other than benign tumors, which improve after removal of the ovarian lesion. We present three cases of pseudo-Meigs' syndrome secondary to ovarian metastasis from colorectal cancer. In case 1, the patient has severe dyspnea and hypoxia due to massive right pleural effusion; therefore preoperative thoracic drainage was needed. In case 2, the patient needed paracentesis every two or three days to improve abdominal distension. After two courses of 5-fluorouracil, levofolinate, and oxaliplatin (mFOLFOX6), her ascites could be controlled by diuretics without aspiration and her general condition improved. Then she underwent operation. In case 3, the patient developed a massive pleural effusion and ascites coincident with a rapid enlargement of ovarian tumor after resection and adjuvant chemotherapy for rectal cancer. In all cases, pleural effusions and/or ascites resolved and general conditions and daily activities of the patients improved after oophorectomy. They are all currently in good health without recurrence of pleural effusion or ascites. In patients with suspected pseudo-Meigs' syndrome secondary to ovarian metastasis of colorectal cancer, operation including oophorectomy may reduce pleural effusions and/or ascites and improve the general condition.

[Two Cases of Fournier's Gangrene That Occurred during Chemotherapy for Rectal Cancer]

Two cases of Fournier's gangrene occurred during chemotherapy for advanced rectal cancer. Patients were treated using surgical debridement and antibiotic therapy. Case 1: A 66-year-old man had advanced rectal cancer with para-aortic and inguinal lymph node metastases. He received a sigmoid colostomy and chemotherapy(capecitabine, oxaliplatin, bevacizumab). Due to progression of the rectal mass, we performed radiotherapy(30 Gy)and chemotherapy(irinotecan, S-1, bevacizumab). After 14 days, he was hospitalized with a diagnosis of Fournier's gangrene with anal pain and fever. Case 2: A 63-year-old man had mucinous rectal carcinoma with sacrum invasion. He received a sigmoid colostomy and chemotherapy. Sixteen days after regorafenib therapy, as a fifth-line of chemotherapy, he was hospitalized with a diagnosis of Fournier's gangrene with hip pain, swollen perineum, and fever. There have been no reports of Fournier's gangrene occurring during chemotherapy for rectal cancer. We report 2 cases with a review of literature.

ASC Induces Apoptosis via Activation of Caspase-9 by Enhancing Gap Junction-Mediated Intercellular Communication

ASC (apoptosis-associated speck-like protein containing a CARD) is a key adaptor molecule of inflammasomes that mediates inflammatory and apoptotic signals. Aberrant methylation-induced silencing of ASC has been observed in a variety of cancer cells, thus implicating ASC in tumor suppression, although this role remains incompletely defined especially in the context of closely neighboring cell proliferation. As ASC has been confirmed to be silenced by abnormal methylation in HT1080 fibrosarcoma cells as well, this cell line was investigated to characterize the precise role and mechanism of ASC in tumor progression. The effects of ASC were examined using in vitro cell cultures based on comparisons between low and high cell density conditions as well as in a xenograft murine model. ASC overexpression was established by insertion of the ASC gene into pcDNA3 and pMX-IRES-GFP vectors, the latter being packed into a retrovirus and subjected to reproducible competitive assays using parental cells as an internal control, for evaluation of cell viability. p21 and p53 were silenced using shRNA. Cell viability was suppressed in ASC-expressing transfectants as compared with control cells at high cell density conditions in in vitro culture and colony formation assays and in in vivo ectopic tumor formation trials. This suppression was not detected in low cell density conditions. Furthermore, remarkable progression of apoptosis was observed in ASC-introduced cells at a high cell density, but not at a low one. ASC-dependent apoptosis was mediated not by p21, p53, or caspase-1, but rather by cleavage of caspase-9 as well as by suppression of the NF-κB-related X-linked inhibitor-of-apoptosis protein. Caspase-9 cleavage was observed to be dependent on gap junction formation. The remarkable effect of ASC on the induction of apoptosis through caspase-9 and gap junctions revealed in this study may lead to promising new approaches in anticancer therapy.

Novel role of ASC as a regulator of metastatic phenotype

Disorders of cytoskeletal remodeling and signal transduction are frequently involved in cancer progression. In particular, apoptosis‐associated speck‐like protein containing a caspase‐recruitment domain (ASC) has been reported a proapoptotic molecule that is epigenetically silenced in several human cancers. ASC is a well‐characterized adaptor protein involved in the formation of multiprotein oligomers, called inflammasomes, and plays a crucial role in the activation and secretion of interleukin‐1β and interleukin‐18 in innate immune cells. However, the function of ASC in the regulation of tumor progression remains elusive. The present investigation examined the involvement of ASC in cancer progression and the acquisition of metastatic ability. To determine the effect of ASC depletion in in vitro and in vivo model systems, ASC was stably knocked down in B16 murine melanoma cell lines using retroviral transduction of shRNA. ASC suppression increased the motility of B16BL6 cells in scratch assays and augmented invasiveness as assessed by a Matrigel‐coated transwell system. Invadopodia formation and Src phosphorylation level were markedly enhanced in ASC‐knockdown cells as well. Since caspase‐8 has been reported to enhance cellular migration by Tyr380 phosphorylation via Src, we examined Tyr380 phosphorylation of caspase‐8 in ASC‐knockdown cells and found it to be elevated in ASC‐knockdown cells but attenuated by z‐VAD‐fmk or z‐IETD‐fmk. Moreover, ASC ablation increased pulmonary metastasis in mice after intravenous injection of B16BL6 cells. Our cumulative findings indicate that ASC suppresses cancer metastasis and progression via the modulation of cytoskeletal remodeling and the Src‐caspase‐8 signaling pathway.

Acute airway obstruction due to benign asymptomatic nodular goiter in the cervical region: A case report

Benign nodular goiter is a common disease. Although large goiters with obstructive symptoms including shortness of breath and dyspnea are a clear indication for surgery, acute upper airway obstruction, particularly in benign cervical goiter cases, is rare. We herein report the case of 46-year-old female with acute upper airway obstruction due to benign nodular goiter. The patient had a large and elastic goiter which was more pronounced on the left side of her neck, and surgery was scheduled for within a few months. Three months after the initial presentation, while still waiting for surgery, the patient was brought to the emergency room due to loss of consciousness and breathing difficulty and was immediately intubated. A computed tomography (CT) scan revealed that the trachea was markedly compressed by a nodular lesion in the left lobe, and bilateral pneumonia was also evident. Total thyroidectomy was immediately performed via the supraclavicular approach. The patient had an uneventful postoperative course and recovered well. The resected specimen included a well-encapsulated solid and cystic mass. Histopathological examination mainly revealed adenomatous goiter. The present case suggests that benign asymptomatic nodular goiter mostly located in the neck may cause acute airway obstruction, even if the nodules are not large. Early surgery should be performed when tracheal deviation and stenosis due to a large goiter is prominent by CT scan.

Clinical significance of apoptosis-associated speck-like protein containing a caspase recruitment domain in oral squamous cell carcinoma

OBJECTIVES

To assess apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) expression in oral squamous cell carcinoma (OSCC) and analyze its clinical and pathological significance.

STUDY DESIGN

ASC expression was studied using immunohistochemistry in 119 OSCCs patients. The relationships between ASC expression and clinical and pathological parameters were statistically analyzed. In addition, the relationships between ASC expression and cell differentiation [IVL (involcrin) expression] and apoptosis (TUNEL [TdT-mediated dUTP nick end labeling] positive cell number) were investigated.

RESULTS

ASC expression showed significant correlations with parameters including clinical tumor stage, mode of invasion, and histological differentiation, and had a significant impact on survival of OSCC. The distribution of ASC correlated well with that of IVL. ASC expression was significantly correlated with the TUNEL-positive cell number.

CONCLUSIONS

Lower ASC expression correlates with clinical and pathological malignancy and, consequently, poor prognosis of OSCC. ASC has a close association with cell differentiation and apoptosis.

ASC-associated inflammation promotes cecal tumorigenesis in aryl hydrocarbon receptor-deficient mice

The aryl hydrocarbon receptor (AhR) plays a suppressive role in cecal carcinogenesis by CUL4B/AhR-mediated ubiquitylation and degradation of β-catenin, which is activated by xenobiotics and natural ligands. AhR-deficient (AhR(-)(/-)) mice develop cecal tumors with severe inflammation. To elucidate whether the tumors develop autonomously in AhR(-/-) mice due to impaired β-catenin degradation or in association with accelerated inflammation, we performed two kinds of experiments using germ-free (GF) AhR(-/-) mice and compound mutant mice lacking genes for AhR and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), which plays an essential role in caspase-1 activation in inflammasomes. Both GF AhR(-/-) and AhR(-/-)•ASC(-/-) mice showed considerably reduced tumor development compared with that in AhR(-/-) mice albeit in a 'cancer-prone' state with aberrant β-catenin accumulation. Blocking of the interleukin (IL)-1β signaling pathway by treatment with a caspase-1 inhibitor, YVAD, reduced cecal tumorigenesis in AhR(-/-) mice. Signal transducers and activators of transcription 3 (STAT3) activation was detected in the cecal epithelium of the AhR(-/-) mice due to enhanced IL-6 production. An inhibitor of the STAT3 signaling pathway, AG490 suppressed the tumor formation. ASC-mediated inflammation was also found to play a critical role in tumor development in Apc(Min/+) mice, a mouse model of familial adenomatous polyposis. Collectively, these results revealed an important role of the bacteria-triggered or ASC-mediated inflammation signaling pathway in the intestinal tumorigenesis of mice and suggest a possible chemical therapeutic intervention, including AhR ligands and inhibitors of the inflammation pathway.

Impaired degradation followed by enhanced recycling of epidermal growth factor receptor caused by hypo-phosphorylation of tyrosine 1045 in RBE cells

Background

Since cholangiocarcinoma has a poor prognosis, several epidermal growth factor receptor (EGFR)-targeted therapies with antibody or small molecule inhibitor treatment have been proposed. However, their effect remains limited. The present study sought to understand the molecular genetic characteristics of cholangiocarcinoma related to EGFR, with emphasis on its degradation and recycling.

Methods

We evaluated EGFR expression and colocalization by immunoblotting and immunofluorescence, cell surface EGFR expression by fluorescence-activated cell sorting (FACS), and EGFR ubiquitination and protein binding by immunoprecipitation in the human cholangiocarcinoma RBE and immortalized cholangiocyte MMNK-1 cell lines. Monensin treatment and Rab11a depletion by siRNA were adopted for inhibition of EGFR recycling.

Results

Upon stimulation with EGF, ligand-induced EGFR degradation was impaired and the expression of phospho-tyrosine 1068 and phospho-p44/42 MAPK was sustained in RBE cells as compared with MMNK-1 cells. In RBE cells, the process of EGFR sorting for lysosomal degradation was blocked at the early endosome stage, and non-degradated EGFR was recycled to the cell surface. A disrupted association between EGFR and the E3 ubiquitin ligase c-Cbl, as well as hypo-phosphorylation of EGFR at tyrosine 1045 (Tyr1045), were also observed in RBE cells.

Conclusion

In RBE cells, up-regulation of EGFR Tyr1045 phosphorylation is a potentially useful molecular alteration in EGFR-targeted therapy. The combination of molecular-targeted therapy determined by the characteristics of individual EGFR phosphorylation events and EGFR recycling inhibition show promise in future treatments of cholangiocarcinoma.

How much length of the distal esophagus is removed by transhiatal approach for squamous cell carcinoma and Barrett's adenocarcinoma in Japanese patients?

BACKGROUND/AIMS

The removed length of the esophagus by transhiatal distal esophagectomy (THDE) for patients with squamous cell carcinoma (SCC) and Barrett's adenocarcinoma (BAC) in the distal/abdominal esophagus was investigated.

METHODOLOGY

Twenty six patients with carcinoma mainly located in the distal/ abdominal esophagus were treated by THDE: SCC (Group-S, n=17) and BAC (Group-A, n=9). The length of the mobilized esophagus (D1) and that of the removed esophagus (D2) were measured. After surgery, we measured the distance between the stapled line of the esophagogastrostomy and the diaphragmatic hiatus (D3). The ratio of D3 to the distance between the bronchial bifurcation and the hiatus (D3-ratio) was calculated.

RESULTS

The mean D1, D2 and D3 were 91.2mm, 65.2mm and 63.2mm, respectively. There were no differences among D1, D2 and D3 between Group-S and Group-A. The mean D3-ratio was 51.9%, and there was no difference between Group-S and Group-A. No postoperative mortality was observed, although postoperative complications were observed in 2 patients (7.7%). After THDE, no local recurrence was observed, node recurrence in 4 (15.4%) and distant metastasis in 7 (26.9%). Five-year survival rate after THDE was 70.1%. Seven patients (26.9%) complained of heartburn and only one of Group-S frequently felt heartburn. In endoscopic findings, most of the patients with heartburn were classified as Grade M.

CONCLUSIONS

Approximately 65mm of the distal esophagus and approximately 50% of the distance between the bronchial bifurcation and the hiatus was safely removed by THDE for SCC and BAC of the distal/abdominal esophagus, in spite of limited cases.

Hyaluronan deficiency in tumor stroma impairs macrophage trafficking and tumor neovascularization

Despite the importance of stromal cells in tumor progression, our overall understanding of the molecular signals that regulate the complex cellular interactions within tumor stroma is limited. Here, we provide multiple lines of evidence that tumor-associated macrophages (TAM) preferentially traffic to stromal areas formed within tumors in a manner dependent on a hyaluronan (HA)-rich tumor microenvironment. To address the role of stroma-derived HA in macrophage recruitment, we disrupted the HA synthase 2 (Has2) gene in stromal fibroblasts using conditional gene targeting. The Has2 null fibroblasts showed severe impairment in recruiting macrophages when inoculated with tumor cells into nude mice, which shows the contribution of stroma-derived HA in intratumoral macrophage mobilization. Furthermore, a deficiency in stromal HA attenuated tumor angiogenesis and lymphangiogenesis concomitantly with impaired macrophage recruitment. Taken together, our results suggest that stromal HA serves as a microenvironmental signal for the recruitment of TAMs, which are key regulatory cells involved in tumor neovascularization.

Esophageal cancer associated with other primary cancers--historical comparison of clinicopathologic features in 359 esophageal cancer patients

BACKGROUND/AIMS

We historically investigated the clinicopathologic features of esophageal cancer associated with other primary cancers (OPC), and discussed differences between the last decade and the previous period.

METHODOLOGY

A total of 359 patients with esophageal cancer treated between 1981 and 2006 were enrolled. They were divided into 2 groups; 213 patients between 1981 and 1996 (Group-A), and 146 patients between 1997 and 2006 (Group-B).

RESULTS

Between Group-A and Group-B, there was a significant difference in the frequency of OPC (15.5% vs. 32.2%, p < 0.001). Regarding the site of OPC, there was a significant difference in the frequency of head and neck cancers (p < 0.001). There was a significant difference in the frequency of metachronous OPC between Group-A and Group-B (5.6% vs. 18.5%, p < 0.001). Antecedent OPC was more frequently observed in Group-B than Group-A (3.3% vs. 11.0%, p < 0.01), and subsequent OPC was also more frequently observed in Group-B than Group-A (2.8% vs. 7.5%, p < 0.05). Although the 5-year survival rate after esophagectomy of the patients without OPC was better in Group-B than Group-A (31.5 % vs. 52.7 %; p < 0.01), there was no difference in that of the patients with OPC between Group-A and Group-B, (40.7% vs. 54.2%).

CONCLUSION

Metachronous as well as synchronous OPC in esophageal cancer patients were more frequent in the recent period than in the previous period. We should consider antecedent, synchronous, and subsequent OPC in esophageal cancer patients.

Killian-Jamieson diverticulitis with cervical cellulitis: report of a case

A Killian-Jamieson (K-J) diverticulum is an uncommon hypopharyngeal diverticulum related to the better-recognized Zenker's diverticulum. Cervical cellulitis due to K-J diverticulitis is also highly exceptional. We report the case of a 53-year-old woman with cervical cellulitis caused by K-J diverticulitis. The cellulitis was cured by the administration of an antibiotic agent. The patient underwent a resection of the K-J diverticulum 2 months after the cellulitis was cured. The cervical diverticulum was judged to be a K-J diverticulum because the diverticulum prolapsed laterally just below the cricopharyngeus muscle on the esophagogram. The left recurrent laryngeal nerve adhered to the proximity of the orifice of the diverticulum. The recurrent laryngeal nerve was carefully preserved before the resection of the diverticulum. Accurate differential diagnosis between K-J and Zenker's diverticula is necessary before surgery to preserve the recurrent laryngeal nerve.