Efficacy of laparoscopic liver resection for small hepatocellular carcinoma located in the posterosuperior segments: A multi-institutional study using propensity score matching by the Kyushu Study Group of Liver Surgery

AIM

Laparoscopic liver resection (LLR) for hepatocellular carcinoma (HCC) located in the posterosuperior segments (PS) have generally been considered more difficult than those for HCC in anterolateral segments (AL), but may be safe and feasible for selected patients with accumulated experience. In the present study, we investigated the effectiveness of LLR for single nodular HCCs ≤3 cm located in PS.

METHODS

In total, 473 patients who underwent partial liver resection for single nodular HCCs ≤3 cm at the 18 institutions belonging to the Kyusyu Study Group of Liver Surgery from January 2010 to December 2018 were enrolled. The short-term outcomes of laparoscopic partial liver resection and open liver resection (OLR) for HCCs ≤3 cm, with subgroup analysis of PS and AL, were compared using propensity score-matching analysis. Furthermore, results were also compared between LLR-PS and LLR-AL.

RESULTS

The original cohort of patients with HCC ≤3 cm included 328 patients with LLR and 145 with OLR. After matching, 140 patients with LLR and 140 with OLR were analyzed. Significant differences were found between groups in terms of volume of blood loss (median, 55 vs. 287 ml, p < 0.001), postoperative complications (0.71 vs. 8.57%, p = 0.003), and postoperative hospital stay (median, 9 vs. 14 days, p < 0.001). The results of subgroup analysis of PS were similar. Short-term outcomes did not differ significantly between LLR-PS and LLR-AL after matching.

CONCLUSIONS

Laparoscopic partial resection could be the preferred option for single nodular HCCs ≤3 cm located in PS.

Adrenocortical carcinoma mimicking hepatocellular carcinoma: A case report

INTRODUCTION AND IMPORTANCE

Adrenocortical carcinoma (ACC) is a relatively rare tumor arising in the adrenal cortex. Its imaging and histopathologic findings are not well known to be similar to those of hepatocellular carcinoma (HCC). We report here a case of ACC with hepatic resection in the preoperative diagnosis of HCC.

CASE PRESENTATION

A 46-year-old woman was noted to have a tumor 45 mm in size in the segment 7 of the liver on CT during a medical checkup. The tumor had consistent imaging findings as HCC on Ultrasound, CT, and MRI examinations, and the result of the liver tumor biopsy was a diagnosis of intermediate differentiated HCC. We considered the tumor to be HCC and performed a posterior segmentectomy with combined resection of the right adrenal gland, which had adhesions suspected to direct invasion. The pathology of the resected specimen confirmed the diagnosis of ACC with direct invasion into the liver.

CLINICAL DISCUSSION

ACC may show a contrast pattern similar to that of HCC on imaging, and histopathology may show atypical cells with eosinophilic sporulation, similar to that of HCC. Our case serves to alert physicians that ACC should be considered a differential diagnosis in patients with suspected HCC in the posterior segment.

CONCLUSION

Tumors suspected of HCC in the dorsal posterior segment of the liver should be considered as possible ACC.

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.

Effect of intraoperative operating table rotation on lower limb perfusion index in patients in the lithotomy position

We focused on "returning to the horizontal position," one of the measures for preventing well leg compartment syndrome implemented at our hospital, and aimed to clarify the effect of intraoperative positional changes by operating table rotation on blood perfusion in the lower extremities during lithotomy in patients under general anesthesia. This prospective observational study examined 64 patients scheduled to undergo general anesthesia in the lithotomy position from March 2021 to May 2022. The primary endpoint was the perfusion index (PI) of the lower limb before and after operating table rotation. The baseline lower limb PI before the operating table rotation was 2.376 (1.591), and the lower limb PI after the change from Trendelenburg to the horizontal position was as follows: immediately after, 2.123 (1.405); 5 minutes, 1.894 (1.138); 10 minutes, 1.915 (1.167); and 15 minutes, 1.993 (1.218). Compared with the baseline, no significant difference was noted in the change in the lower limb PI due to the Trendelenburg to horizontal positional change. The baseline lower leg pressure before the operating table rotation was 51.4 (13.4) mm Hg, and the lower leg pressure after the change from the Trendelenburg to the horizontal position was as follows: immediately after, 36.6 (10.3) mm Hg; 5 minutes, 36.5 (10.2) mm Hg; 10 minutes, 36.4 (10.0) mm Hg; and 15 minutes, 36.5 (10.2) mm Hg. Compared with the baseline, the change in lower leg pressure due to the Trendelenburg to horizontal positional change showed a significant decrease immediately afterward (P < .001). After operating table rotation from the Trendelenburg to the horizontal position, the lower limb PI did not change significantly after 15 min. However, lower leg pressure showed a significant decrease immediately after returning to the horizontal position. This result provides evidence for operating table rotation as a preventive measure for well leg compartment syndrome.

Prognostic Impact of Relative Dose Intensity of Adjuvant Chemotherapy With S-1 on Pancreatic Ductal Adenocarcinoma

BACKGROUND/AIM

Although adjuvant chemotherapy (AC) with S-1 is currently the standard treatment for pancreatic ductal adenocarcinoma (PDAC) in Japan, the associations between its relative dose intensity (RDI) and survival outcomes remain unclear.

PATIENTS AND METHODS

We reviewed 310 patients with PDAC who had undergone pancreatectomy from January 2014 to June 2020 at three institutions. Of these, patients who had received adjuvant S-1 monotherapy were analyzed. Patients who had died or developed recurrences within 6 months, or received neoadjuvant chemotherapy, were excluded from the analyses. Possible predictors of overall survival (OS), including RDI, were analyzed using Cox regression. The cutoff value for RDI was determined by receiver operating characteristic analysis.

RESULTS

Ninety-four patients with a median age of 69 years (range=39-84 years) were analyzed. In the high-RDI group (RDI≥72.3%, n=74), the OS rates were 98.5% and 80.8% at 1 and 3 years, respectively, whereas in the low-RDI group (RDI <72.3%, n=20) they were 88.9% and 51.6%, respectively (p=0.001). By multivariate analysis, lymph node metastasis [hazard ratio (HR)=3.06; p=0.020], low RDI (HR=2.95; p=0.020), and time interval from surgery to initiation of AC > 51 days (HR=2.50; p=0.046) were independently associated with inferior OS. The combination of the latter two factors clearly stratified both OS and recurrence-free survival (p<0.001 and p=0.017, respectively).

CONCLUSION

Early initiation and maintenance of RDI of S-1 monotherapy after pancreatectomy may improve the OS of PDAC patients.

Hepatocellular carcinoma with situs inversus totalis treated by caudate lobectomy: A case report

Introduction

Situs inversus totalis (SIT) is a congenital anatomical variant in which organs and vasculature are positioned in a mirror-image relationship to the normal condition. Therefore, the surgical procedures need to be carefully planned with these factors in mind.

Case presentation

A 57-year-old man with SIT was diagnosed with a hepatocellular carcinoma (HCC) and was planned for caudate lobectomy. As preoperative preparation, 3D reconstructed images were created based on the contrast-enhanced CT images, and careful simulations were performed on the vascular anomalies and location of the tumor. There was a replaced left hepatic artery forming a common trunk with a left gastric artery. In addition, using media player software, a previous caudate lobectomy video was played in right and left inverted mode to simulate the abdominal surgical field image in SIT. The operative time was 285 min, and the blood loss was 440 ml. The preoperative careful simulation allowed us to proceed with the surgery without significant discomfort.

Conclusion

Even in the case of hepatocellular carcinoma with SIT, hepatectomy for hepatocellular carcinoma can be safely performed by careful preoperative simulations.

•

This is a case of caudate lobectomy for hepatocellular carcinoma with situs inversus totalis.

•

We repeatedly watched a previous caudate lobectomy video played in right and left inverted mode prior to the surgery.

•

With careful preoperative simulations, liver resection can be safely performed in patients with SIT.

Application of laparoscopic distal pancreatectomy for normal anatomy after hiatal hernia repair: A case report

We describe a case of pancreatic tumor associated with a giant type IV hiatal hernia that had prolapsed into the posterior mediastinum. Hiatal hernia repair should be performed first because it enables laparoscopic distal pancreatectomy to be performed in the normal anatomical position.

A case of retroperitoneal abscess caused by infection of urachal remnant

Infection of urachal remnant may cause recurrent abscesses. In the current case report, we describe a urachal remnant infection leading to a retroperitoneal abscess, which is an extremely rare condition. In such cases, the recommended treatment is urachal remnant resection.

The urachal remnant infection leading to a retroperitoneal abscess is an extremely rare condition. Urachal remnant resection is the recommended treatment for radical cure.

Evaluation of Preoperative Magnetic Resonance Cholangiopancreatography in Acute Cholecystitis to Predict Technical Difficulties in Laparoscopic Cholecystectomy

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging technique that provides high-quality visualization of the biliary tree, including the gallbladder. This study aimed to evaluate the useful-ness of preoperative MRCP for acute cholecystitis in predicting technical difficulties during laparoscopic chole-cystectomy (LC). A total of 168 patients who underwent LC with preoperative MRCP were enrolled in this study. Patients were divided into two groups according to preoperative MRCP findings: the visualized group (n = 126), in which the entire gallbladder could be visualized; and the non-visualized group (n = 42), in which the entire gallbladder could not be visualized. The perioperative characteristics and postoperative complica-tions of the two groups were retrospectively analyzed. Operation time was longer in the non-visualized group (median 101.5 vs. 143.5 min; p < 0.001). The non-visualized group had significantly more intraoperative blood loss than the visualized group (median 5 vs. 10 g; p = 0.05). The rate of conversion to open cholecystectomy was significantly higher in the non-visualized group (1.6 vs. 9.5%; p = 0.03). In conclusion, patients in the non- visualized group showed higher difficulty in performance of LC. Our MRCP-based classification is a simple and effective means of predicting difficulties in performing LC for acute cholecystitis.

Validity of a model using routinely collected data for identifying infections following gastric, colorectal, and liver cancer surgeries

PURPOSE

Validating outcome measures is a prerequisite for using administrative databases for comparative effectiveness research. Although the Japanese Diagnosis Procedure Combination database is widely used in surgical studies, the outcome measure for postsurgical infection has not been validated. We developed a model to identify postsurgical infections using the routinely-collected Diagnosis Procedure Combination data.

METHODS

We retrospectively identified inpatients who underwent surgery for gastric, colorectal, or liver cancer between April 2016 and March 2018 at four hospitals. Chart reviews were conducted to identify postsurgical infections. We used bootstrap analysis with backwards variable elimination to select independent variables from routinely-collected diagnosis and procedure data. Selected variables were used to create a score predicting the chart review-identified infections, and the performance of the score was tested.

RESULTS

Among the 756 eligible patients, 102 patients (13%) had postoperative infections. Three variables were identified as predictors: diagnosis of infectious disease recorded as a complication arising after admission, addition of an intravenous antibiotic, and bacterial microscopy or culture. The prediction model had a C-statistic of 0.891 and pseudo-R² of 0.380. A cut-off of 1 point of the score showed a sensitivity of 92% and specificity of 71%, and a cut-off of 2 points showed a sensitivity of 77% and specificity of 91%.

CONCLUSIONS

Our model using routinely-collected administrative data accurately identified postoperative infections. Further external validation would lead to the application of the model for research using administrative databases. This article is protected by copyright. All rights reserved.

Increased Expression of the lncRNA NRON Along With NFATc1/PIM-1 in Labial Salivary Glands of Sjögren's Syndrome Patients

The aim of our study was to analyze the expressions of nuclear factor of activated T cells (NFAT)-related substances including long noncoding RNA NRON which participates in pathophysiology of Sjögren's syndrome (SS), and to assess the histologic findings in individuals with SS. In this study, the expressions of NRON, NFATc1, CD3/CD4, and proviral integration site for Moloney murine leukemia virus (PIM)-1 were examined by in situ hybridization, immunohistochemical analysis, and immunofluorescence in labial salivary glands (LSGs) obtained from 16 patients with SS and five controls. The microcell count method has been applied to calculate the NFATc1-positive area/infiltrating cell area in LSGs, and we compared those results to the infiltrating cell area, focus score, serum immunoglobulin G, and the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index. The NRON expression in the nuclei of cell-infiltration lesions of the SS patients were prominent. The NFATc1 expression was strong in the cytoplasm of infiltrating mononuclear cells and weak in ducts of both SS and controls. In SS, the NFATc1-positive area/infiltrating cell area was positively correlated with the infiltrating cell area and focus score. CD3/CD4 was expressed in infiltrating mononuclear cells, and PIM-1 colocalized with NFATc1 in the cytoplasm. These results suggest NRON along with NFATc1/PIM-1 in SS LSGs might participate in SS pathophysiology.

Wandering spleen with splenic arteriovenous torsion

Splenic arteriovenous torsion causes splenomegaly and ischemic necrosis of the spleen. The recommended treatment for wandering spleen with hypersplenism is considered to be splenectomy.

Carcinosarcoma of the Thoracic Esophagus That Presented as Focal Ulcerative Lesion

Esophageal carcinosarcoma is a rare malignant tumor composed of both carcinomatous and sarcomatous elements. We report a case of esophageal carcinosarcoma in a 56-year-old woman with dysphagia. Esophageal ulcerative tumors were detected by endoscopy and resected by thoracoscopic esophagectomy. Carcinosarcoma was confirmed by the presence of both carcinomatous and sarcomatous tumor components. On immunohistochemistry, the sarcomatous area was positive for keratin staining, while the sarcomatous area was positive for vimentin staining. The tumor reportedly had a better prognosis than SCC of the esophagus, especially in terms of survival rate. The patient's disease was classified as ypT3N0M0, ypStage II. No definitive diagnosis was made preoperatively. We report this case along with a review of the literature.

Synchronous Total Occlusion of the Celiac Axis and Superior Mesenteric Artery: An Autopsy Case

Acute mesenteric ischemia (AMI) is often caused by superior mesenteric artery (SMA) embolization. We report a rare case of synchronous celiac axis and SMA embolization in an elderly woman with initially mild abdominal pain. Ultimately, a second contrast-enhanced computed tomography revealed extensive necrosis from the stomach to the transverse colon together with liver ischemia due to hours of occlusion. Multiorgan failure made palliation the only option, and she died the following evening. Autopsy revealed a fragile atherosclerosis-asso-ciated thrombus. Careful examination and repeat diagnostic tests should be performed in patients with mild abdominal symptoms at risk for AMI.

Pretreatment Absolute Lymphocyte Count and Neutrophil-to-lymphocyte Ratio Are Prognostic Factors for Stage III Breast Cancer

BACKGROUND/AIM

Stage III breast cancer comprises a broad spectrum of disease, including the extent of supraclavicular/internal mammary lymph node metastasis. In this study, we evaluated the usefulness of the absolute lymphocyte count (ALC) and neutrophil-to-lymphocyte ratio (NLR) in predicting the prognosis of patients with stage III breast cancer.

PATIENTS AND METHODS

Seventy-five patients with stage III breast cancer who underwent surgery were included. We compared their clinicopathological factors according to the presence or not of supraclavicular/internal mammary lymph node metastasis, and pretreatment ALC or NLR.

RESULTS

Patients with metastasis of the studied lymph nodes had a poorer prognosis in comparison to those without metastasis. In patients without these types of lymph node metastasis, both the ALC and NLR were predictive factors for relapse-free and overall survival. Among these patients, those with a low ALC or high NLR had recurrence-free and overall survival comparable to those of patients with supraclavicular/internal mammary lymph node metastasis.

CONCLUSION

Pretreatment ALC and NLR were prognostic factors for patients with stage III breast cancer.

A case of cystic duct syndrome

In the diagnosis of gallbladder induced pain without gallstones, drip-infusion cholangiographic computed tomography, and endoscopic retrograde cholangiography are useful in differentiating cystic duct syndrome.

Immunotherapeutic advances in gastric cancer

Advanced gastric cancers are responsible for overwhelming human suffering and death. Despite the development of combination chemotherapies, the survival rates of patients with gastric cancer remain unsatisfactory. Given the growing evidence of the benefits of immunotherapy as an alternative treatment for other cancers such as advanced melanoma, non-small cell lung cancer, renal cell carcinoma, and refractory Hodgkin's lymphoma, researchers have begun to explore its application in the treatment of gastric cancer. Three types of immunotherapy have shown promising effects against gastric cancer: immune checkpoint inhibitors, chimeric antigen rector (CAR)-T cells, and tumor vaccines. Clinical trials have used either immuno-oncology monotherapies or combination immuno-chemotherapies to improve the overall survival times and objective response rates of patients with gastric cancer. We review the clinical efficacy of immunotherapy including checkpoint inhibitors, CAR‑T, and tumor vaccines, in the treatment of gastric cancer. Based on initial evidence, we believe that immunotherapy could positively impact the natural history and improve the outcomes of a subgroup of patients with gastric cancer.

Aberrant common hepatic artery from the left gastric artery and with no connection to the gastroduodenal artery: Risky vascular anomaly in gastrectomy

Knowledge of anatomical variations of the celiac axis is important in upper abdominal surgery. Aberrant common hepatic artery originating from the left gastric artery without connecting the gastroduodenal artery is extremely rare. Preoperative vascular anatomy assessment using reconstructions of CT images may be useful for safe surgical procedure.

Serum kynurenine levels are a novel biomarker to predict the prognosis of patients with hepatocellular carcinoma

BACKGROUND

We examined serum kynurenine levels in patients with chronic hepatitis C virus infection, and the relationship between serum kynurenine and prognosis in patients with hepatocellular carcinoma (HCC) and chronic hepatitis C.

METHODS

We retrospectively analyzed 604 patients with HCC diagnosed between January 1999 and December 2015, and 288 patients without HCC who were seen at the National Hospital Organization Nagasaki Medical Center between October 2014 and November 2017. The association between serum kynurenine and prognosis was evaluated using the Cox's proportional hazards regression analysis.

RESULTS

Patients with HCC had significantly higher values of serum kynurenine than patients without HCC (median: 557.1 vs. 464.2 ng/mL, p<0.001). Five-year survival rates of HCC patients with serum kynurenine ≥900 (n = 65), 600-899 (n = 194), and <600 ng/mL (n = 345) were 30.6%, 47.4%, and 61.4%, respectively (p = 0.001, log-rank test). Multivariate analysis identified serum kynurenine as an independent predictor for prognosis of HCC patients. The hazard ratio of serum kynurenine ≥900, and 600-899 compared with serum kynurenine <600 ng/mL were 1.91 (p<0.001) and 1.37 (p = 0.015), respectively.

CONCLUSIONS

A high level of serum kynurenine correlated with poor prognosis of HCC. Serum kynurenine levels may be a novel biomarker to predict the prognosis of patients with HCC. The development of drugs that inhibit kynurenine production is expected to help improve the prognosis of patients with HCC.

Cricopharyngeal myotomy for cricopharyngeus muscle dysfunction after esophagectomy

Background

Pharyngoesophageal dysphagia sometimes develops after esophagectomy. However, severe dysphagia after esophagectomy due to cricopharyngeus muscle dysfunction is a rare complication. There are no recommended clinical treatments for cricopharyngeus muscle dysfunction after esophagectomy. We report a case of myotomy for cricopharyngeus muscle dysfunction after esophagectomy.

Case presentation

A 75-year-old man with mild dysphagia diagnosed with advanced esophageal cancer by esophagogastroduodenoscopy at a clinic was admitted to our hospital. He had occasional mild dysphagia when he swallowed solid foods. After chemotherapy, the patient underwent minimally invasive esophagectomy with regional lymph node dissection and was reconstructed with a gastric conduit and cervical anastomosis by the retrosternal route. Aspiration pneumonia developed after esophagectomy without paralysis of the vocal cords. In esophagoscopy, there was no stricture around the anastomosis. However, severe pharyngoesophageal dysphagia with cricopharyngeus muscle dysfunction was revealed by videofluoroscopic examination. Bilateral cricopharyngeal myotomy was performed because balloon dilations had failed. The histological findings revealed atrophy and fibrosis of the cricopharyngeus muscle fibers. Pharyngoesophageal dysphagia improved immediately after myotomy. The patient swallowed solid food easily without dysphagia 12 months after myotomy.

Conclusion

Dysphagia after esophagectomy was worsened by cricopharyngeus muscle dysfunction. Cricopharyngeus myotomy may lead to long improvement of pharyngo-oesophageal dysphagia after esophagetomy.

Clinicopathological characteristics of combined hepatocellular cholangiocarcinoma from the viewpoint of patient prognosis after hepatic resection: High rate of early recurrence and its predictors

AIM

Combined hepatocellular cholangiocarcinoma (cHCC-CCA) is a very rare subtype of primary liver carcinoma; therefore, its clinicopathological characteristics have not yet been elucidated in detail. The aim of the study was to reveal the clinicopathological characteristics and prognostic factors of cHCC-CCA after hepatic resection (HR) METHODS: A total of 124 patients who underwent curative HR for cHCC-CCA between 2000 and 2016 were enrolled in this multi-institutional study conducted by the Kyushu Study Group of Liver Surgery. Clinicopathological analysis was performed from the viewpoint of patient prognosis.

RESULTS

A total of 62 patients (50%) had early recurrence within 1.5 years after HR, including 36 patients (58%) with extrahepatic recurrence. In contrast, just four patients (3%) had late recurrence occurring >3 years after HR. The independent predictors of early recurrence were as follows: des-gamma carboxyprothrombin >40 mAU/mL (odds ratio 26.2, P = 0.0117), carbohydrate antigen 19-9>37 IU/l (odds ratio 18.0, P = 0.0200), and poorly differentiated HCC or CCA (odds ratio 11.2, P = 0.0259).

CONCLUSIONS

Half of the patients with cHCC-CCA had early recurrence after HR. Preoperative elevation of des-gamma carboxyprothrombin or carbohydrate antigen 19-9 and the existence of poorly differentiated components of HCC or CCA in resected specimens are predictors of its early recurrence.

S-1 and CPT-11 Plus Ramucirumab (IRIS+Rmab) as Second-Line Chemotherapy for Patients with Oxaliplatin-Refractory Metastatic Colorectal Cancer (mCRC): A Multicenter Phase II Study in Japan (N-DOCC-F-C-1701)

This multicenter phase II N-DOCC-F-C-1701 trial is being planned in order to investigate the efficacy and safety of CPT-11+S-1 +Ramucirumab (IRIS+Rmab), which is anticipated to have a stronger anti-tumor effect than IRIS+Bmab in patients with metastatic colorectal cancer (mCRC) previously treated with oxaliplatin (L-OHP) containing regimen, in consideration of the result of RAISE, FIRIS and some phase II trials of IRIS+Bevacicizumab (Bmab). The number of patients is set at 38 for the statistical analysis, assuming an expected median PFS of 5.0 months (threshold: 3.0 months). The primary endpoint of the study is the progression free survival (PFS), and the secondary endpoints are the overall response rate (ORR), overall survival (OS), adverse events (AE), quality of life (QOL) and review of nausea and vomiting. This trial is registered in the UMIN Clinical Trials Registry as UMIN000028170. We intend to start conducting the trial in September 1, 2017. If this trial meets the endpoint, IRIS+Rmab might be supported as a new optional standard regimen for mCRC.

Nondegenerated cystic neuroendocrine tumor of the pancreas: a case report

Background

Pancreatic neuroendocrine tumors (PNETs) are typically solid neoplasms but, in very rare cases, present as cystic lesions. We describe a case of a cystic neuroendocrine tumor that developed as a small cystic lesion.

Case presentation

In 2011, a 66-year-old Japanese woman underwent computed tomography (CT) that revealed a cystic lesion in the tail of the pancreas measuring 9 mm. She did not have any symptoms. She underwent a CT scan every year thereafter. The cystic lesion gradually increased and was 40 mm in 2019; endoscopic retrograde pancreatography (ERP) was then performed. Cytological examination demonstrated class IIIb adenocarcinoma, and we conducted laparoscopic distal pancreatectomy. Pathological examination showed PNET.

Conclusion

Although cystic change of PNET is generally caused by ischemia or necrosis inside the tumor, in our case, PNET occurred as a small cyst that increased without changing form.

Asymptomatic versus symptomatic metastatic breast cancer: Potential effects on prognosis and quality adjusted life years (QALYs)

e13073

Background: After radical surgery for breast cancer, routine laboratory or imaging studies for metastases screening are not indicated in the absence of clinical signs and symptoms suggestive of recurrence. While the goal of therapy is the extension of survival and maintenance of quality of life (QOL), therapies themselves could induce adverse events, resulting in deterioration of QOL. We evaluated quality adjusted life years (QALYs), which is survival adjusted by QOL, of the patients with recurrent breast cancer retrospectively and adequate follow-up measures. Methods: Fifty seven patients with recurrent breast cancer who died already were included. Survival curves were partitioned into two health states: time with ≥ grade 2 chemotherapy-related toxicity (TOX) and time without toxicity (TWiST). QALYs were acquired as follows: QALYs = TWiST + 0.7 * TOX. We compared clinical factors in the patients between with (symptomatic group, n = 32) and without symptoms (asymptomatic group, n = 25). Results: The median age of the patient at diagnosis of recurrence was 57 years. Luminal (hormone receptors (HR) - and human epidermal growth factor receptor-2 (HER2) -), HER2 (HER2 +), triple negative (TN) (HR - and HER2 -), and unknown were 29, 7, 15, and 6 cases, respectively. The proportion of HER2 and TN was significantly higher in the symptomatic group than that in the asymptomatic group (58.6, 21.7 %, p < 0.05). 44.6 % of the patients had visceral metastases at diagnosis of recurrence and the proportions were not different between the groups. Although post recurrent survival (PRS) was shorter significantly in the symptomatic group (22.5, 42,0 months, p < 0.01), overall survival from diagnosis of primary breast cancer (OS) was identical (60.5, 91.0 months). Additionally, QALYs after recurrence was shorter in the symptomatic group (23.0, 41.1 months, p < 0.01) and QALYs from diagnosis of primary breast cancer was identical (58.7, 91.0 months). Conclusions: Although there was no significant difference in OS between the both groups, the duration of therapy received was longer in the symptomatic group. In the present study, we acquired limited information due to retrospective manner. Prospective evaluation of QALYs, including patient reported outcome and symptoms derived from cancer itself, would turn out adequate measures of follow-up after radical surgery for primary breast cancer.

Increased favorability of small breast cancers

e12576

Background: Breast cancer is classified into three prognostic groups based on the following biologic factors: estrogen-receptor (ER) status, progesterone-receptor (PR) status, and nuclear grade (NG). According to this classification, we determined the biological behavior in order to understand if a small breast cancer is biologically more favorable than a large one (T1-2 breast cancers). Methods: The inclusion criteria for this study were (1) presence of T1-2 breast cancer measurable by magnetic resonance imaging (MRI) or ultrasound(US), and (2) availability for determination of ER, PR, and NG histological status. Inflammatory breast cancer, male breast cancer, tumors of unknown size on MRI or US, and complications due to other cancers were excluded from this study. From April 2007 to December 2019, 1173 patients with surgically proven breast cancer presented at National Hospital Organization Nagasaki Medical Center, and 1080 patients were retrospectively analyzed. The favorable (F), intermediate (I), and unfavorable (UF) groups were defined as follows. F: NG1 (ER+PR+, ER+PR-, ER-PR+), UF: NG2 (ER-PR-) or NG3 (ER-PR-, ER+PR-, ER-PR+). IF: all other types of F and UF. Overall survival (OS) was calculated using the Kaplan-Meier method. All statistical analyses were performed using JMP 9.0.2, and probability values of <0.05 were considered statistically significant. Results: Number (%), age (year), size (cm), and 10-year OS (%) in the F, I, and UF groups are presented in the table. The tumor size in F group was significantly smaller than that in the other groups and had better prognoses. The F, I, and UF distribution of tumors less than 1 cm in size were 66%, 29%, and 5%, respectively. On the other hand, the F, I, and UF distribution of tumors 1-2 cm, 2-3 cm, 3-4 cm, 4-5 cm in sizes were (42%, 41%, 17%), (34%, 46%, 20%), (31%, 39%, 30%), and (27%, 45%, 28%), respectively. The 10-year OS of F group stage I, I group stage I, F group stage II, and UF group stage I were 99%, 94%, 93%, and 80%, respectively. Conclusions: Small breast cancers, especially those less than 1 cm in size, were shown to be significantly biologically favorable. Small breast cancers are candidates for de-escalation of treatment. [Table: see text]

Integrated GWAS and mRNA Microarray Analysis Identified IFNG and CD40L as the Central Upstream Regulators in Primary Biliary Cholangitis

Genome‐wide association studies (GWASs) in European and East Asian populations have identified more than 40 disease‐susceptibility genes in primary biliary cholangitis (PBC). The aim of this study is to computationally identify disease pathways, upstream regulators, and therapeutic targets in PBC through integrated GWAS and messenger RNA (mRNA) microarray analysis. Disease pathways and upstream regulators were analyzed with ingenuity pathway analysis in data set 1 for GWASs (1,920 patients with PBC and 1,770 controls), which included 261 annotated genes derived from 6,760 single‐nucleotide polymorphisms (P < 0.00001), and data set 2 for mRNA microarray analysis of liver biopsy specimens (36 patients with PBC and 5 normal controls), which included 1,574 genes with fold change >2 versus controls (P < 0.05). Hierarchical cluster analysis and categorization of cell type–specific genes were performed for data set 2. There were 27 genes, 10 pathways, and 149 upstream regulators that overlapped between data sets 1 and 2. All 10 pathways were immune‐related. The most significant common upstream regulators associated with PBC disease susceptibility identified were interferon‐gamma (IFNG) and CD40 ligand (CD40L). Hierarchical cluster analysis of data set 2 revealed two distinct groups of patients with PBC by disease activity. The most significant upstream regulators associated with disease activity were IFNG and CD40L. Several molecules expressed in B cells, T cells, Kupffer cells, and natural killer–like cells were identified as potential therapeutic targets in PBC with reference to a recently reported list of cell type–specific gene expression in the liver. Conclusion: Our integrated analysis using GWAS and mRNA microarray data sets predicted that IFNG and CD40L are the central upstream regulators in both disease susceptibility and activity of PBC and identified potential downstream therapeutic targets.

COMPARATIVE STUDY ON PERFORMANCE OF VARIOUS ENVIRONMENTAL RADIATION MONITORS

After the Fukushima Daiichi Nuclear Power Plant accident, the radiation dose for first responders was not evaluated accurately due to lack of the monitoring data. It has been important to evaluate a radiation dose for workers in emergency response at a nuclear accident. In this study, a new device which can evaluate both of external and internal exposure doses was developed and the performance of various environmental radiation monitors including commercially available monitors were tested and compared from the viewpoint of an environmental monitoring at emergency situation. Background counts of the monitors and the ambient dose equivalent rate were measured in Fukushima Prefecture. The detection limit for beta particles was evaluated by the method of ISO11929. The sensitivity for gamma-rays of the dust monitor using a ZnS(Ag) and a plastic scintillator was high, but that of the external exposure monitor using a silicon photodiode with CsI(Tl) crystal was relatively low. The detection limit ranged 190-280 Bq m-3 at 100 μSv h-1, exceeding the detection limit of 100 Bq m-3 in the minimum requirement by the National Regulation Authority in Japan. Use of the shielding with lead is necessary to achieve the minimum requirement. These results indicate that the dust monitor using a ZnS(Ag) scintillator and a plastic scintillator is suitable for the external exposure monitor and the developed internal exposure monitor is for the internal exposure monitor at emergency situation among the evaluated monitors. In the future study, the counting efficiency, the relative uncertainty and the performance of the detection for alpha particles will be evaluated, and it will be considered which type of a monitor is suitable after taking the portability into account.

Difficulty scoring system in laparoscopic distal pancreatectomy

BACKGROUND

Several factors affect the level of difficulty of laparoscopic distal pancreatectomy (LDP). The purpose of this study was to develop a difficulty scoring (DS) system to quantify the degree of difficulty in LDP.

METHODS

We collected clinical data for 80 patients who underwent LDP. A 10-level difficulty index was developed and subcategorized into a three-level difficulty index; 1-3 as low, 4-6 as intermediate, and 7-10 as high index. The automatic linear modeling (LINEAR) statistical tool was used to identify factors that significantly increase level of difficulty in LDP.

RESULTS

The operator's 10-level DS concordance between the 10-level DS by the reviewers, LINEAR index DS, and clinical index DS systems were analyzed, and the weighted Cohen's kappa statistic were at 0.869, 0.729, and 0.648, respectively, showing good to excellent inter-rater agreement. We identified five factors significantly affecting level of difficulty in LDP; type of operation, resection line, proximity of tumor to major vessel, tumor extension to peripancreatic tissue, and left-sided portal hypertension/splenomegaly.

CONCLUSIONS

This novel DS for LDP adequately quantified the degree of difficulty, and can be useful for selecting patients for LDP, in conjunction with fitness for surgery and prognosis.

Predictors of portal and splenic vein thrombosis after laparoscopic splenectomy: a retrospective analysis of a single-center experience

PURPOSE

Laparoscopic splenectomy (LS) has become the standard operative approach for splenectomy. Portal or splenic vein thrombosis (PSVT) is a serious and common complication after LS, and lethal complications of PSVT can occur when the portal vein is completely occluded by portal vein thrombosis (PVT). We aimed to clarify the predictors of PSVT after LS and to determine which of them were also predictors of PVT.

METHODS

A total of 56 consecutive patients who underwent elective LS were enrolled in this study. The patients were divided into two groups based on the presence or absence of PSVT after LS. In addition, patients with PSVT were divided into two groups: a PVT group and a non-PVT group. The preoperative and intraoperative clinical data were compared among the groups.

RESULTS

Thirty (53.6%) patients developed PSVT. The splenic vein diameter was the most useful predictor for the development of PSVT, and 10 mm was an accurate splenic vein diameter cut-off value for use as a predictive factor for PSVT. In addition, the splenic vein diameter was the most useful predictor of the development of PVT from splenic vein thrombosis (SVT), and 14 mm was found to be an accurate cut-off value.

CONCLUSION

PSVT is a common postoperative complication that is identified on enhanced computed tomography. The splenic vein diameter is not only a predictor of PSVT but also of the development of PVT from SVT.

The long-term survival in primary retroperitoneal mucinous cystadenocarcinoma: a case report

Background

Primary retroperitoneal mucinous cystadenocarcinoma (PRMC) is extremely rare, and its biological behavior, pathogenesis, optimum treatments, and prognosis remain to be elucidated. We herein report a case of PRMC with an 80-month follow-up.

Case presentation

A 29-year-old woman was diagnosed with unknown retroperitoneal tumor with benign right ovarian cyst and uterine fibroids, and she underwent laparotomy. The tumor was completely resected with a subsequent histopathological diagnosis of primary retroperitoneal mucinous cystadenocarcinoma (PRMC). Eighty months after surgery, she remains recurrence-free.

Conclusion

PRMC is an extremely rare tumor. Only around 60 cases have so far been published in the literature. The preoperative diagnosis of PRMC is difficult, and a definitive diagnosis can usually only be made based on the findings of histopathological examinations after surgery. Presently, only radical resection is useful for both diagnostic and therapeutic purposes. The optimal long-term management after surgery is still not well established. Further studies on PRMC are therefore needed to elucidate the etiology and establish effective treatments.

In vivo construction of liver tissue by implantation of a hepatic non-parenchymal/adipose-derived stem cell sheet

Subcutaneous hepatocyte sheet implantation is an attractive therapeutic option for various liver diseases. However, this technique is limited by the availability of hepatocytes. Thus, the use of hepatic non-parenchymal cells (NPCs) containing small hepatocytes, which have the ability to proliferate more rapidly than mature hepatocytes, for transplantation has been suggested. The aim of our study was to construct liver tissue subcutaneously in rats by implanting NPC sheets co-cultivated with adipose-derived stem cells (ADSCs), which produce certain angiogenic factors. We crafted NPC-ADSC sheets on temperature-responsive culture dishes. NPCs formed functioning bile canaliculi and stored glycogen. In addition, their ability to produce albumin was not inferior to that of hepatocytes. Albumin production increased over time when co-cultivated with ADSCs. We then implanted the co-cultivated cell sheets subcutaneously. The co-cultivated sheets retained glycogen, formed bile canaliculi, showed signs of vascularization and survived subcutaneously without pre-vascularization. These results suggest that NPCs can be a viable option in cell therapy for liver diseases. This technique using co-cultivated cell sheets may be useful in the field of regenerative medicine. Copyright © 2017 John Wiley & Sons, Ltd.

Improvement of Anal Function by Adipose-Derived Stem Cell Sheets

AIM

One of the most troublesome complications of anal preserving surgery is anal sphincter dysfunction. The aim of this study was to evaluate functional recovery after implantation of adipose-derived stem cell (ADSC) sheets, novel biotechnology, for an anal sphincter resection animal model.

METHODS

Eighteen female Sprague-Dawley rats underwent removal of the nearest half of the internal and external anal sphincter muscle. Nine rats received transplantation with ADSC sheets to the resected area while the remaining rats received no transplantation. The rats were evaluated for the anal function by measuring their resting pressure before surgery and on postoperative days 1, 7, 14, 28, and 56. In addition, the rats were examined for the presence of smooth muscle and also to determine its origin.

RESULTS

The improvement of the anal pressure was significantly greater in the ADSC sheet transplantation group compared with the control group. Histologically, at the vicinity of the remaining smooth muscle, reproduction of smooth muscle was detected. Using in fluorescence in situ hybridization, the cells were shown to be from the recipient.

CONCLUSION

Regenerative therapy using ADSC sheet has the potential to recover anal sphincter dysfunction due to anorectal surgery.

A Modified Method for Purifying Gallbladder Epithelial Cells Using Fluorescence-activated Cell Sorting

BACKGROUND

We have previously reported a procedure for isolating and culturing biliary epithelial cells (BECs). The aim of this study was to reconsider the method for obtaining pure BECs using the mouse gallbladder.

MATERIALS AND METHODS

Cells that were obtained from the gallbladder alone were sorted by fluorescence-activated cell sorting (FACS) for purifying based on the expression of the epithelial cell adhesion molecule (EpCAM). The viability rate was measured based on the negative expression of 7-aminoactinomycin D (7-AAD).

RESULTS

More than 75% of cells from the gallbladder were determined to be pure BECs. An analysis of the EpCAM revealed that 73.3% of the cells were 7-AAD-negative. Finally, the 0.82×10⁶ pure BECs that survived were obtained and seeded on a collagen gel plate. However, these pure BECs showed almost no proliferation.

CONCLUSION

Pure BECs could be accumulated using FACS. However, the number of BECs was insufficient for the culturing process.

Analysis of early relaparotomy following living donor liver transplantation

We retrospectively analyzed the causes, risk factors, and impact of early relaparotomy after adult-to-adult living donor liver transplantation (LDLT) on the posttransplant outcome. Adult recipients who underwent initial LDLT at our institution between August 1997 and August 2015 (n = 196) were included. Any patients who required early retransplantation were excluded. Early relaparotomy was defined as surgical treatment within 30 days after LDLT. Relaparotomy was performed 66 times in 52 recipients (a maximum of 4 times in 1 patient). The reasons for relaparotomy comprised postoperative bleeding (39.4%), vascular complications (27.3%), suspicion of abdominal sepsis or bile leakage (25.8%), and others (7.6%). A multivariate analysis revealed that previous upper abdominal surgery and prolonged operative time were independent risk factors for early relaparotomy. The overall survival rate in the relaparotomy group was worse than that in the nonrelaparotomy group (6 months, 67.3% versus 90.1%, P < 0.001; 1 year, 67.3% versus 88.6%, P < 0.001; and 5 years, 62.6% versus 70.6%, P = 0.06). The outcome of patients who underwent 2 or more relaparotomies was worse compared with patients who underwent only 1 relaparotomy. In a subgroup analysis according to the cause of initial relaparotomy, the survival rate of the postoperative bleeding group was comparable with the nonrelaparotomy group (P = 0.96). On the other hand, the survival rate of the vascular complication group was significantly worse than that of the nonrelaparotomy group (P = 0.001). Previous upper abdominal surgery is a risk factor for early relaparotomy after LDLT. A favorable longterm outcome is expected in patients who undergo early relaparotomy due to postoperative bleeding. Liver Transplantation 22 1519-1525 2016 AASLD.

Generating tissue-engineered intestinal epithelium from cultured Lgr5 stem cells in vivo

Introduction

Generating tissue-engineered small intestine (TESI) from mature intestinal cells has been established in a mouse model. The purpose of this study was to generate TESI from Lgr5 stem cells in vivo.

Methods

We used Lgr5-EGFP mice for intestinal crypt isolation. After seven days, cultured crypts with Lgr5 stem cells were seeded onto a biodegradable polymer and implanted into omentum of NOD/SCID mice.

Results

Engineered intestinal epithelium was generated from Lgr5 stem cells after four weeks of in vivo implantation. Intestinal epithelium was immunohistochemically positive for Paneth cells, enteroendocrine cells, goblet cells, microvilli of the absorptive enterocytes and Ki67.

Conclusion

Our observations suggest that transplanted Lgr5 stem cells can differentiate into the intestinal epithelium in vivo with further proliferative activity.