Clinical Implications and Risk Factors of Dilatation of Remnant Pancreatic Duct at 1 Year After Pancreatoduodenectomy: A Prospective, Japanese, Multicenter, Observational Cohort Study (DAIMONJI-Study).

BACKGROUND: To determine the precise frequency of main pancreatic duct (MPD) dilatation within the remnant pancreas at 1 year after pancreatoduodenectomy (PD) and its clinical implications, a prospective multicentre cohort study was performed in patients without MPD dilatation before PD (Registry number; UMIN000029662). METHODS: Between October 2017 and July 2020, patients with MPD diameter <3mm who were planned to undergo PD for periampullary lesions at 21 hospitals were enrolled. The primary endpoints were frequency of MPD dilatation at 1 year after PD, and the relationship between MPD dilatation and pancreatic endo- and exocrine function, nutritional status, and fatty liver. Secondary endpoints were risk factors for MPD dilatation at 1 year after PD and time-course change in MPD diameter. RESULTS: Of 200 registered patients, 161 patients were finally analyzed. Pancreatic fistula was the most frequent complication (n=76; 47.2%). MPD dilatation (MPD>3mm) at 1 year after PD was seen in 35 patients (21.7%). Pancreatic exocrine function, assessed by steatorrhea, was significantly impaired in patients with MPD dilatation. However, endocrine function, nutrition status and fatty liver development were comparable between the two groups. In multivariate analysis, the serum toral protein level≥7.3g/dl was an independent predictor for MPD dilatation at 1 year after PD (OR; 3.12, 95%CI; 1.31-7.15). A mean MPD diameter significantly increased at 6 months after PD and kept plateau thereafter. CONCLUSIONS: MPD dilatation at 1 year after PD was seen in 21.7% of patients and significantly associated with exocrine function impairment but not with endocrine function, nutrition status, or development of fatty liver.

Morphology of the Dorsal Pancreatic Artery and Its Oncological Significance in Pancreatic Cancer.

OBJECTIVES: Although the dorsal pancreatic artery (DPA) is an important artery that supplies the pancreas, its morphology has not been sufficiently studied. We investigated the morphology of the DPA and the progression of pancreatic cancer along this vessel. MATERIALS AND METHODS: Overall, 142 patients with pancreatic cancer who underwent surgical resection at Kanazawa University Hospital between 2004 and 2015 were enrolled. We examined the morphology of the DPA using preoperative computed tomography and cancer progression along the DPA using resected specimens. We investigated the anatomical structures surrounding the DPA through cadaveric examination. RESULTS: The analysis of computed tomography images revealed the presence of the DPA in 141 patients. In typical cases, the DPA divides into a head and a body branch. Histopathological examination revealed cancer progression along the DPA in 32 patients. Cancer progression along the DPA was identified as a factor associated with a poor prognosis in pancreatic head or body cancer. Cadaveric examination showed the presence of abundant nerve and lymphatic tissues along the DPA. CONCLUSIONS: It is important to remove the soft tissue surrounding the DPA during surgery for pancreatic head or body cancer because it may serve as an important route for cancer progression.

Identification of patients at high risk for recurrence in carcinoma of the ampulla of Vater: Analysis in 460 patients.

Aim: Carcinoma of the ampulla of Vater (CAV) shows a favorable prognosis compared to that with the other periampullary tumors, while some cases have a poor prognosis. The aims of the present study are to clarify the clinicopathological factors associated with poor recurrence-free survival (RFS) in patients with CAV after curative resection and to validate the usefulness of adjuvant chemotherapy (AC). Patients: The study design is a multicenter retrospective cohort study. Patients with CAV who underwent pancreaticoduodenectomy between January 2008 and December 2020 at 26 hospitals were analyzed. The 30 clinicopathological factors were evaluated. A propensity score matching (PSM) was used to compare between patients with and without AC. Results: Finally, 460 patients were analyzed. Median duration of follow-up was 47.2 months. Twenty-one prognostic factors associated with poor RFS were identified by univariate analysis. In multivariate analysis, aged ≥71, tumor diameter ≥12 mm, pT2 or higher stage (pT≥2), portal vein invasion (PV+), venous invasion(V+), and node positive disease (pN+) were independent prognostic factors for poor RFS. Out of 80 patients who received AC, 63 patients were assigned to analysis for PSM. The results showed no beneficial effect of AC on RFS. The preoperative factors potentially predicting pT≥2, V+, and/or N+ were at least one of following; (1) CA19-9 > 37 IU/mL, (2) ulcerative or mixed type appearance, (3) except for well-differentiated tumor, or (4) except for intestinal subtype of histology. Conclusions: Aged ≥71, tumor diameter ≥12 mm, pT≥2, PV+, V+, and pN+ were independent prognostic factors for poor RFS in patients with CAV. An additional therapeutic strategy may be desirable in CAV patients at high risk for recurrence.

Standard versus delayed initiation of S-1 adjuvant chemotherapy after surgery for pancreatic cancer: a secondary analysis of a nationwide cohort by the Japan Pancreas Society.

BACKGROUND: Based on the Japan Adjuvant Study Group of Pancreatic Cancer-01 results, S-1 adjuvant chemotherapy has been the standard in resected pancreatic ductal adenocarcinoma (PDAC) patients in Japan and elsewhere, initiated within 10 weeks after surgery. To assess the clinical impact of this timing, we conducted a secondary analysis of a nationwide survey by the Japan Pancreas Society. METHODS: A total of 3361 patients were divided into two groups: 2681 (79.8%) initiating the therapy within 10 weeks after surgery (standard) and 680 (20.2%) after 10 weeks (delayed). We compared recurrence-free survival (RFS) and overall survival (OS) using the log-rank test and Cox proportional hazards model with conditional landmark analysis between the groups. Results were verified by adjustment with inverse-probability-of-treatment weighting (IPTW) analysis. RESULTS: The median timing of S-1 adjuvant chemotherapy initiation was 50 days (interquartile range: 38-66). In the standard group, 5-year RFS and OS rates were 32.3-48.7%, respectively, compared with 25.0-38.7% in the delayed group. Hazard ratios (HRs) and 95% confidence intervals were 0.84 (0.76-0.93) for RFS (p < 0.001) and 0.77 (0.69-0.87) for OS (p < 0.001). The IPTW analysis yielded 5-year RFS rates of 32.1% and 25.3% in the standard versus delayed group, respectively [HR = 0.86 (0.77-0.96), p < 0.001] and 5-year OS rates of 48.3% and 39.8%, respectively [HR = 0.81 (0.71-0.92), p < 0.001]. CONCLUSIONS: Initiation of S-1 adjuvant chemotherapy in resected PDAC patients within 10 weeks after surgery may offer survival benefit over later initiation.

Is frequent measurement of tumor markers beneficial for postoperative surveillance of colorectal cancer?

PURPOSE: To determine whether frequent measurement of tumor markers triggers early detection of colorectal cancer recurrence. METHODS: Of 1,651 consecutive patients undergoing colorectal cancer surgery between 2010 and 2016, 1,050 were included. CEA and CA 19-9 were considered to be postoperative tumor markers and were measured every 3 months for 3 years, and then every 6 months for 2 years. Sensitivity analysis of elevated CEA and CA19-9 levels and multivariate analysis of factors associated with elevated CEA and CA19-9 levels were performed. The proportion of triggers for detecting recurrence was determined. RESULTS: The median follow-up period was 5.3 years. After applying the exclusion criteria, 1,050 patients were analyzed, 176 (16.8%) of whom were found to have recurrence. After excluding patients with persistently elevated CEA and CA19-9 levels before and after surgery from the 176 patients, 71 (43.6%) of 163 patients had elevated CEA levels and 35 (20.2%) of 173 patients had elevated CA19-9 levels. Sensitivity/positive predictive values for elevated CEA and CA19-9 levels at recurrence were 43.6%/32.3% and 20.2%/32.4%, respectively. Lymph node metastasis was a factor associated with both elevated CEA and CA19-9 levels at recurrence. Of the 176 patients, computed tomography triggered the detection of recurrence in 137 (78%) and elevated tumor marker levels in 13 (7%); the diagnostic lead interval in the latter 13 patients was 1.7 months. CONCLUSION: Tumor marker measurements in surveillance after radical colorectal cancer resection contribute little to early detection, and frequent measurements are unnecessary for stage I patients with low risk of recurrence.

Impact of S-1 adjuvant chemotherapy longer than 6 months on survival in patients with resected pancreatic cancer: a nationwide survey by the Japan Pancreas Society based on real-world data.

BACKGROUND: Based on the Japan Adjuvant Study Group of Pancreatic Cancer 01 study, the standard duration of adjuvant chemotherapy with S-1 (an oral 5-fluorouracil prodrug consisting of tegafur, gimeracil, and oteracil) in patients with resected pancreatic ductal adenocarcinoma (PDAC) was considered to be 6 months, but the impact of increasing its duration on postoperative survival was unknown. Here, the authors investigated this question by reviewing real-world data from a large cohort of patients with PDAC. METHODS: In total, 3949 patients who underwent surgery for PDAC during the study period followed by S-1 adjuvant chemotherapy in board-certified institutions were included. Based on the duration of S-1 chemotherapy, two subgroups were defined: a standard-duration group that included patients who were treated for 180 ± 30 days and a longer duration group that included patients who received treatment for >210 days. RESULTS: The median duration of S-1 chemotherapy was 167 days, with a mean ± standard deviation of 200 ± 193 days. After excluding patients who had a recurrence within 210 days after the initiation of adjuvant chemotherapy, postoperative recurrence-free survival (RFS) and overall survival (OS) in the standard-duration group (n = 1473) and the longer duration group (n = 975) were compared. RFS and OS did not differ significantly between the standard-duration and longer duration groups (5-year RFS: 37.8% vs. 36.2% respectively; p = .6186; 5-year OS: 52.8% vs. 53.4%, respectively; p = .5850). The insignificant difference was verified by multivariate analysis and propensity-score matching analysis. CONCLUSIONS: The current findings suggest that extending S-1 adjuvant chemotherapy beyond 6 months has no significant additional effect on survival in patients with PDAC. This could be useful in determining whether to extend S-1 chemotherapy in patients who have completed the standard 6-month treatment.

Verification of Resectability Status for Pancreatic Cancer: Radiological and Pathological Analysis of Patients Undergoing Pancreatoduodenectomy With Combined Resection of the Superior Mesenteric Artery.

OBJECTIVES: Resectability status is considered an important indicator for progression of pancreatic cancer. We verified the superior mesenteric artery (SMA) factors of resectability status by radiological and pathological analysis in patients who underwent pancreatoduodenectomy with combined resection of the SMA. METHODS: We enrolled 22 patients who underwent pancreatoduodenectomy with combined resection of the SMA. Patients were divided into 3 groups according to the contact angle between the tumor and the SMA in preoperative computed tomography images (no contact, R-sma; contact within 180 degrees, BR-sma; contact more than 180 degrees, UR-sma). We pathologically evaluated cancer progression toward the SMA. RESULTS: There were 3 patients with R-sma, 12 with BR-sma, and 7 with UR-sma. The median distance (mm) between the cancer and the SMA was 7.0 with R-sma, 1.0 with BR-sma, and 0 with UR-sma (P = 0.0003). Invasion to the superior mesenteric nerve plexus was positive in none with R-sma, 11 with BR-sma, and 7 with UR-sma (P < 0.0001). Invasion to the SMA was positive in none with R-sma and BR-sma, and 7 with UR-sma (P < 0.0001). CONCLUSIONS: Superior mesenteric artery factors of resectability status are reliable indicator for cancer progression toward the SMA.

The necessity of intensive surveillance colonoscopy for patients with a remaining right colon after resection of colorectal cancer: a retrospective cohort study.

PURPOSE: To clarify how often postoperative surveillance colonoscopy should be undertaken based on the risk factors for the development of metachronous cancer (MC) and advanced adenoma (AA) after surgery for colorectal cancer. METHODS: We collected data of consecutive patients who underwent curative resection for primary colorectal cancer between 2005 and 2012, with preoperative colonoscopy and surveillance colonoscopy at 1 year after surgery (406 patients, mean age: 69 years, 59% male). The detection rates of AA (with villous features, > 10 mm or high-grade dysplasia) and MC by surveillance colonoscopy were the primary outcomes. RESULTS: At 5 years, colonoscopy was performed as postoperative surveillance an average of 3.2 times. AA and MC were detected in 57 (14.0%) and 18 patients (4.4%), respectively. Both lesions were more common in the right colon (n = 43) than in the left colon (n = 28). The detection rate did not differ to a statistically significant extent according to the number of colonoscopies performed for surveillance (p = 0.21). However, after left-sided colectomy, both types of lesions were more commonly detected in those who received ≥ 3 colonoscopies than in those with one or two colonoscopies (p = 0.04). CONCLUSION: A remaining right colon after left-sided colectomy was associated with a higher risk of developing AA and MC. Physicians should consider performing surveillance colonoscopy more frequently if the right colon remains after surgery.

Bleeding from pancreatic arteriovenous malformation with duodenal ulcer penetration. Case report and literature review.

Dilated vessels at the ulcer floor of the second part of the duodenum can be signs of pancreatic arteriovenous malformation; contrast-enhanced computed tomography should be performed, and surgical treatment should be considered.

[Sigmoid Colon Cancer with Lateral Lymph Node Metastasis That Presented with Gastric Perforation].

A 74-year-old man visited his local clinic complaining of abdominal pain that persisted for three days. He was diagnosed with diffuse peritonitis and was transported to our hospital. Contrast computed tomography(CT)showed gastric perforation and a tumor in the sigmoid colon with left obturator lymph node metastasis. He was diagnosed with diffuse peritonitis resulting from gastric perforation and performed emergent surgery. As the size of the gastric perforation was large, we performed distal gastrectomy and transverse colostomy. He was discharged without any complications, and a total of 6 courses of SOX with a bevacizumab regimen were administered postoperatively. CT following chemotherapy showed shrinkage of the lesion. He was admitted again for sigmoidectomy with left lateral lymph node resection and discharged from the hospital on postoperative day 8. We administered 2 courses of SOX regimen after the surgery. He remains alive with no recurrence 27months after the first surgery.

[A Case of Type 4 Ascending Colon Cancer Showing Early Postoperative Lymphangitis Carcinomatosa].

A 56-year-old man was admitted to our hospital because abdominal CT showed wall thickening of the ascending colon. Colonoscopyshowed type 4 colon cancer, diagnosed as poorlydifferentiated adenocarcinoma bybiopsy , with circumferential stenosis. Enhanced CT after admission also showed obstructive ileus and lymphadenopathy leading to a paraaortic lesion, but no other distant metastases were seen. Right hemicolectomywas performed. Histological examination showed poorlydifferentiated adenocarcinoma extending from the hepatic flexure to the terminal ileum, with marked invaded vessels and stromal fibrosis, which was diagnosed as type 4 colon cancer of scirrhous and lymphangiosis types. On the 10th postoperative day, he developed lymphangitis carcinomatosa. Intensive treatment including steroid therapy was not effective, and he died of respiratory failure on the 26th day. Type 4 colon cancer is rare and has very poor prognosis. We report a case and literature review.

International consensus on definition and criteria of borderline resectable pancreatic ductal adenocarcinoma 2017.

This statement was developed to promote international consensus on the definition of borderline resectable pancreatic ductal adenocarcinoma (BR-PDAC) which was adopted by the National Comprehensive Cancer Network (NCCN) in 2006, but which has changed yearly and become more complicated. Based on a symposium held during the 20th meeting of the International Association of Pancreatology (IAP) in Sendai, Japan, in 2016, the presenters sought consensus on issues related to BR-PDAC. We defined patients with BR-PDAC according to the three distinct dimensions: anatomical (A), biological (B), and conditional (C). Anatomic factors include tumor contact with the superior mesenteric artery and/or celiac artery of less than 180° without showing stenosis or deformity, tumor contact with the common hepatic artery without showing tumor contact with the proper hepatic artery and/or celiac artery, and tumor contact with the superior mesenteric vein and/or portal vein including bilateral narrowing or occlusion without extending beyond the inferior border of the duodenum. Biological factors include potentially resectable disease based on anatomic criteria but with clinical findings suspicious for (but unproven) distant metastases or regional lymph nodes metastases diagnosed by biopsy or positron emission tomography-computed tomography. This also includes a serum carbohydrate antigen (CA) 19-9 level more than 500 units/ml. Conditional factors include the patients with potentially resectable disease based on anatomic and biologic criteria and with Eastern Cooperative Oncology Group (ECOG) performance status of 2 or more. The definition of BR-PDAC requires one or more positive dimensions (e.g. A, B, C, AB, AC, BC or ABC). The present definition acknowledges that resectability is not just about the anatomic relationship between the tumor and vessels, but that biological and conditional dimensions are also important. The aim in presenting this consensus definition is also to highlight issues which remain controversial and require further research.

[A Case of Type 4 Gastric Cancer with Esophageal Invasion That Responded to Neoadjuvant Chemotherapy Containing S-1 and Oxaliplatin followed by Surgery].

We encountered a case of type 4 gastric cancer with esophageal invasion that responded to neoadjuvant chemotherapy containing S-1 and oxaliplatin(SOX)followed by surgery, which could be curative resection. A 46-year-old man was referred to our hospital because of abnormal upper gastrointestinal series findings. He was diagnosed with type 4 advanced gastric cancer with esophageal invasion, cT4b(diaphragm)N2M0, Stage ⅢC, and 3 courses of neoadjuvant SOX therapy were administered. Adverse events were minor. After NAC, the primary lesion and lymph nodes showed marked reductions on CT; total gastrectomy and subtotal thoracic esophagectomy were performed. The pathological response to NAC was evaluated as Grade 2 in the primary tumor and Grade 3 in the lymph node; overall, NAC showed considerable antitumor effects. The final diagnosis was ypT3N0M0P0CY0H0, StageⅡA, and was judged as curatively resected. Currently, we are continuing to administer adjuvant chemotherapy containing S-1.

Clinical features of cystatin A expression in patients with pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal malignancy known, with an extremely poor prognosis due to the lack of an efficient diagnostic scheme and no radical treatment option, except surgery. Therefore, understanding the pathophysiology of, and finding a novel biomarker to detect, PDAC should be prioritized. We observed an increase in mRNA expression of the cysteine protease inhibitor cystatin A (CSTA) in CD4+ T cells in peripheral blood cells of nine patients with PDAC, compared with the expression in seven healthy volunteers. Moreover, we confirmed significantly higher CSTA mRNA expression in a larger cohort of 41 patients with PDAC compared with that in 20 healthy volunteers. Correspondingly, the serum CSTA concentrations in 36 patients with PDAC were higher than those in 37 healthy volunteers, and this increase was correlated with PDAC clinical stage. Furthermore, the expression of CSTA and cathepsin B, which is a lysosomal cysteine protease inhibited by CSTA, was observed in tumor tissues and tumor-infiltrating immune cells in 20 surgically resected PDAC tissues by immunohistochemical staining. Expression of CSTA was detected in some tumor tissues and many tumor-infiltrating immune cells. Cathepsin B expression was also observed in most tumor tissues and tumor-infiltrating immune cells. In conclusion, CSTA and its substrate cathepsin B are involved in PDAC-related inflammation. The increment of CSTA expression in peripheral blood of patients with PDAC may have a potential role as a PDAC immunopathologic biomarker.

Location of the meso-pancreatoduodenum as a regional lymphatic basin for pancreatic head carcinoma.

The meso-pancreatoduodenum is the primary site of tumor infiltration in patients with pancreatic head cancer, with numerous patients exhibiting lymph node metastases. Effective dissection of the regional lymphatic basin requires knowledge of the patterns of the arterial branches. The present study examined the patterns of the arteries feeding the pancreatic head and the distribution of the meso-pancreatoduodenum. The present study included 123 patients with pancreatic cancer who underwent contrast-enhanced preoperative 64-multidetector-computed tomography to determine the routes of the inferior pancreaticoduodenal and first jejunal arteries. Surgical specimens and cadavers were also evaluated histologically to clarify the distribution of the meso-pancreatoduodenum. The feeding arteries were divided into three types, with 64.2% of patients having type A, 28.4% having type B and 7.3% having type C branches. The branches emerged from the back or left side of the superior mesenteric artery and ran to the far side of the pancreatic head in an arc. Consequently, the meso-pancreatoduodenum had a roll-shaped appearance, surrounding the trunk arteries and extending to the left side of the superior mesenteric artery. Dissecting the right and left sides of the superior mesenteric artery during lymphadenectomy could improve the effectiveness of resection.

Low-dose gemcitabine induces major histocompatibility complex class I-related chain A/B expression and enhances an antitumor innate immune response in pancreatic cancer.

We investigated the effect of gemcitabine (GEM), a key drug for pancreatic cancer treatment, on the expression of cell surface MICA/B in pancreatic cancer cells and resulting cytotoxicity of γδ T cells. We assessed the effect of GEM on the upregulation of cell surface MICA/B expression by flow cytometry, utilizing six pancreatic cancer cell lines. MICA and CD16 expressions from resected pancreatic cancer patient specimens, which received neoadjuvant chemotherapy (NAC) with GEM, were analyzed by immunohistochemistry. GEM could increase MICA/B expression on cell surface in pancreatic cancer cell lines (in 2 of 6 cell lines). This effect was most effectively at concentration not affecting cell growth of GEM (0.001 µM), because MICA/B negative population was appeared at concentration at cytostatic and cytotoxic effect to cell growth (0.1 and 10 µM). The cytotoxic activity of γδ T cells against PANC-1 was detected and functions through interactions between NKG2D and MICA/B. However, the enhancement of NKG2D-dependent cytotoxicity with increased MICA/B expression, by GEM treatment, was not observed. In addition, soluble MIC molecules were released from pancreatic cancer cell lines in culture supernatant with GEM treatment. Immunohistochemical staining demonstrated that MICA expression in tumor cells and CD16 positive cells surrounding tumors were significantly higher in the NAC group compared to that of the control group. There was a significant correlation between NAC and MICA expression, as well as NAC and CD16 positive cell expression. The present results indicate that low-dose GEM-induced MICA/B expression enhances innate immune function rather than cytotoxicity in pancreatic cancer. In addition, our result suggests that the inhibition of cleavage and release of MIC molecules from the tumor surface could potentially improve NKG2D-dependent cytotoxicity.

[A Study of Patients with Regional Lymph Node Recurrence after Breast Surgery].

Regional lymph node recurrence without distant metastasis after the initial treatment of breast cancer is a relatively rare event. The optimal management for regional lymph node recurrence is poorly understood. We retrospectively evaluated 21 patients who developed regional lymph node recurrence between January 1, 2003 and December 31, 2014. The median interval between regional lymph node recurrence and distant metastasis was 1.0 years(range, 0.4 to 2.5 years). On followup, 15 cases(71.4%)were found to eventually develop distant metastases. Median follow-up time after lymph node recurrence was 1.8 years(range, 0.4 to 20.3 years). The 2-year survival rate after regional lymph node recurrence was 65.5%. The mean distant-disease-free interval was 2.2 years in patients with estrogen receptor(ER)-positive tumor(n=10)and 0.7 years in patients with ER-negative tumor(n=11). The distant-disease-free interval after regional lymph node recurrence was significantly shorter in patients with ER-negative tumor than in patients with ER-positive tumor(p=0.008). The 2-year survival rate after regional lymph node recurrence was significantly lower in patients with ER-negative tumor(33.3%)than in patients with ER-positive tumor(100%, p=0.016). This study revealed that regional lymph node recurrence after initial treatment is associated with an increased risk of distant metastasis and death and ER-negative tumors are indicative of a poor prognosis.

[A Case of Gastrointestinal Stromal Tumor(GIST)Originating in the Anal Canal].

We report a case of a gastrointestinal stromal tumor(GIST)that originated in the anal canal. A 70's woman with a subcutaneous tumor reaching from the anal canal was referred to our hospital. After a thorough examination, the tumor was resected percutaneously in the jackknife position. Histopathological examination showed proliferation of spindle-shaped tumor cells arranged in irregular bundles. Immunohistochemical staining showed that the tumor was positive for c-kit and CD34, and negative for a-SMA and S-100, so the tumor was diagnosed as GIST. As a-SMA-positive smooth muscle cells were seen around the tumor, we suspected that this tumor originated from the internal sphincter muscle.

Massive pneumoretroperitoneum arising from emphysematous cholecystitis: a case report and the literature review.

BACKGROUND: Emphysematous cholecystitis is a severe variant of acute cholecystitis caused by anaerobic bacteria. Although intraperitoneal air as a complication has been described in association with emphysematous cholecystitis, pneumoretroperitoneum arising from emphysematous cholecystitis is extremely rare. Herein, we describe a rare case of pneumoretroperitoneum arising from emphysematous cholecystitis that was successfully treated with emergency surgery. CASE PRESENTATION: An 84-year-old male was transported to the Emergency Department of our hospital for acute abdomen. Computed tomography revealed acute cholecystitis accompanied by emphysematous change. Computed tomography also revealed massive pneumoretroperitoneum complicated with pneumobilia and gas in the hepatoduodenal ligament. Clinical findings fulfilled the diagnostic criteria for systemic inflammatory response syndrome and sepsis. Emergency surgery was carried out with a diagnosis of both emphysematous cholecystitis and gastrointestinal perforation. Intraoperative findings revealed acute gangrenous cholecystitis and pneumoretroperitoneum presenting with an odor-free foamy abscess along the loose connective tissue behind the ascending colon and mesocolon. No evidence of gastrointestinal perforation was found during surgery. Therefore, cholecystectomy and lavage drainage were performed. Bacterial culture examination isolated a single species of anaerobe, Klebsiella pneumoniae, which was considered to be the cause of emphysematous cholecystitis, pneumobilia, and pneumoretroperitoneum. CONCLUSIONS: Emphysematous cholecystitis should be considered as a possible cause of pneumoretroperitoneum. The present case is the first report of massive pneumoretroperitoneum extending to the dorsal side of the ascending mesocolon as a complication of emphysematous cholecystitis.

Oxaliplatin-based chemotherapy induces extravasated platelet aggregation in the liver.

Oxaliplatin-based chemotherapy plays a central role in the treatment of patients with colorectal liver metastasis (CRLM). This treatment, however, has been associated with hepatic sinusoidal obstruction syndrome (SOS), a clinically important adverse effect characterized by a bluish hue of the liver, splenomegaly and thrombocytopenia, resulting in liver dysfunction. The significant association between the sinusoidal endothelium and platelets has suggested that oxaliplatin-based chemotherapy affects platelets in the liver. This study compared platelet counts in patients who did and did not receive oxaliplatin-based neoadjuvant chemotherapy (NAC). The peripheral blood platelet count was significantly lower in the NAC group (n=17) compared to that in the non-NAC, or control group (n=15) (P<0.05). The spleen index was also higher in the NAC group, although the difference was not significant. However, the spleens of the patients in the NAC group were significantly enlarged following treatment (P<0.01). Immunostaining for the platelet surface marker CD42b (glycoprotein Ib), revealed more platelets in the liver in the NAC compared to the control group, particularly in the centrilobular zone III, adjacent to the hepatic central vein and in contact with hepatocytes (P<0.01). The platelets present in the spaces of Disse, referred to as extravasated platelet aggregation (EPA), secrete a number of growth factors, including transforming growth factor-ß, vascular endothelial growth factor-A, plasminogen activator inhibitor-1 and thromboxane A2. In conclusion, EPA may play an important role in the development of hepatic SOS. Moreover, antiplatelet drugs may prevent the onset of SOS and hepatic injury in patients treated with oxaliplatin-based chemotherapy for CRLM.