Yoshikazu Yasuda

Transpapillary intraductal US prior to biliary drainage in the assessment of longitudinal spread of extrahepatic bile duct carcinoma

BACKGROUND The utility of intraductal US via the transpapillary route prior to biliary drainage in the assessment of longitudinal extension of extrahepatic bile duct carcinoma was investigated. METHODS In 19 patients with extrahepatic bile duct carcinoma who underwent surgical resection, an ultrasonic probe (diameter, 2.0 mm; frequency, 20 MHz) was inserted into the bile duct via the transpapillary route prior to biliary drainage. Longitudinal cancer extension along the bile duct was prospectively determined and compared with the histologic findings in the resected specimens. RESULTS Results on the hepatic side were as follows: Intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 9 of 19 patients with one instance of overdiagnosis. The accuracy of intraductal US in assessing the extent of spread (84%) was superior to that of cholangiography (47%) (p < 0.05). Results on the duodenal side were as follows: In patients with suprapancreatic bile duct cancer (n = 14), intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 8 of 14 patients. The accuracy of intraductal US in assessing the extent of the spread (86%) was superior to that of cholangiography (43%) (p < 0.05). CONCLUSIONS Transpapillary intraductal US prior to biliary drainage is useful in demonstrating longitudinal extension of bile duct cancer. However, the surgical margins were inaccurate in some patients.

Evaluation of venous invasion by Elastica van Gieson stain and tumor budding predicts local and distant metastases in patients with T1 stage colorectal cancer.

Evaluation of pathologic predictors of metastases in T1 stage colorectal cancer may be difficult with hematoxylin and eosin (HE) staining alone. The aim of this study was to clarify the role of pathologic predictors by using immunohistochemical staining and Elastica van Gieson (EVG) staining. One hundred and twenty-four patients who underwent bowel resection for single T1 stage colorectal cancer from 1990 to 2004 in 1 institution were studied. D2-40, EVG staining, and CAM5.2 were used to detect lymphatic invasion, venous invasion, and tumor budding, respectively. These 3 factors were separately evaluated based on HE staining. Histology was reviewed by 1 pathologist. Lymph node metastases in the surgical specimen were the standard reference, and distant metastases were identified by periodic computed tomography for 2 years or more after surgery. A logistic regression model was applied to analyze risk factors for lymph node metastases and a Cox regression model for distant metastases. In predicting lymph node metastases, univariate analysis demonstrated significance for all predictors except venous invasion by HE staining. Multivariate analysis showed that venous invasion by EVG and tumor budding by HE showed significance as predictors. In predicting distant metastases, univariate analysis showed significance for lymphatic invasion shown by D2-40, tumor budding shown by CAM5.2 and HE, and lymph node metastases. Multivariate analysis showed only venous invasion by EVG stain as being significantly associated with distant metastases (P=0.001). In conclusion, venous invasion evaluated shown by EVG staining is a useful pathologic predictor for metastases in T1 stage colorectal cancer.

Chromosome copy number analysis in screening for prognosis-related genomic regions in colorectal carcinoma

Colorectal carcinoma (CRC) remains the major cause of cancer death in humans. Although chromosomal structural anomaly is presumed to play an important role in the carcinogenesis of CRC, chromosomal copy number alterations (CNA) and loss of heterozygosity (LOH) have not yet been analyzed extensively at high resolution in CRC. Here we aim to identify recurrent CNA and LOH in human CRC with the use of single nucleotide polymorphism‐typing microarrays, and to reveal their relevance to clinical outcome. Surgically resected CRC specimens and paired normal mucosa were obtained from a consecutive series of 94 patients with CRC, and both of them were subjected to genotyping with Affymetrix Mapping 50K arrays. CNA and LOH were inferred computationally on every single nucleotide polymorphism site by integrating the array data for paired specimens. Our large dataset reveals recurrent CNA in CRC at chromosomes 7, 8, 13, 18, and 20, and recurrent LOH at chromosomes 1p, 4q, 5q, 8p, 11q, 14q, 15q, 17p, 18, and 22. Frequent uniparental disomy was also identified in chromosomes 8p, 17p, and 18q. Very common CNA and LOH were present at narrow loci of <1 Mbp containing only a few genes. In addition, we revealed a number of novel CNA and LOH that were linked statistically to the prognosis of the patients. The precise and large‐scale measurement of CNA and LOH in the CRC genome is efficient for pinpointing prognosis‐related genome regions as well as providing a list of unknown genes that are likely to be involved in CRC development. (Cancer Sci 2008; 99: 1835–1840)

NLRP3 Regulates Neutrophil Functions and Contributes to Hepatic Ischemia–Reperfusion Injury Independently of Inflammasomes

Inflammation plays a key role in the pathophysiology of hepatic ischemia–reperfusion (I/R) injury. However, the mechanism by which hepatic I/R induces inflammatory responses remains unclear. Recent evidence indicates that a sterile inflammatory response triggered by I/R is mediated through a multiple-protein complex called the inflammasome. Therefore, we investigated the role of the inflammasome in hepatic I/R injury and found that hepatic I/R stimuli upregulated the inflammasome-component molecule, nucleotide-binding oligomerization domain–like receptor (NLR) family pyrin domain–containing 3 (NLRP3), but not apoptosis-associated speck–like protein containing a caspase recruitment domain (ASC). NLRP3−/− mice, but not ASC−/− and caspase-1−/− mice, had significantly less liver injury after hepatic I/R. NLRP3−/− mice showed reduced inflammatory responses, reactive oxygen species production, and apoptosis in I/R liver. Notably, infiltration of neutrophils, but not macrophages, was markedly inhibited in the I/R liver of NLRP3−/− mice. Bone marrow transplantation experiments showed that NLRP3 not only in bone marrow–derived cells, but also in non-bone marrow–derived cells contributed to liver injury after I/R. In vitro experiments revealed that keratinocyte-derived chemokine–induced activation of heterotrimeric G proteins was markedly diminished. Furthermore, NLRP3−/− neutrophils decreased keratinocyte-derived chemokine–induced concentrations of intracellular calcium elevation, Rac activation, and actin assembly formation, thereby resulting in impaired migration activity. Taken together, NLRP3 regulates chemokine-mediated functions and recruitment of neutrophils, and thereby contributes to hepatic I/R injury independently of inflammasomes. These findings identify a novel role of NLRP3 in the pathophysiology of hepatic I/R injury.

Pathological Predictors for Lymph Node Metastasis in T1 Colorectal Cancer

PurposeTo clarify pathological predictor for lymph node metastasis in T1 colorectal cancer.MethodsOne hundred and sixty-four patients who underwent surgery for single T1 colorectal cancer were reviewed. The pathological differentiations of non-well differentiation, invasion depth (≥2 000 μm), lymphatic channel involvement, venous invasion, and tumor budding were selected as candidate predictors. Tumor budding was estimated according to the definition proposed by Ueno et al. (Gastroenterology 2004; 127:385–394). The lymph node status was set for the endpoint. Logistic regression model was applied to analyze the predictors.ResultsLymph node involvement was observed in 9.8%. The positive rates were 13.4% for the pathological differentiations of non-well differentiation, 51.8% for invasion depth (≥2 000 μm), 6.1% for lymphatic channel involvement, 8.5% for venous invasion, and 14.6% for tumor budding. The pathological differentiations of non-well differentiation (P < 0.001) and tumor budding (P = 0.002) were significantly associated with lymph node metastasis in multivariate analysis. When either two significant factors was adopted for the prediction of the lymph node metastasis, the sensitivity, specificity, positive predictive value, and negative predictive value were 94%, 82%, 36%, and 99%, respectively.ConclusionThe pathological differentiations of non-well differentiation and tumor budding are useful predictors for lymph node metastasis in T1 colorectal cancer.

Limitation of cholangiography in assessing longitudinal spread of extrahepatic bile duct carcinoma to the hepatic side.

Background: Preoperative assessment of longitudinal spread of bile duct carcinoma (BDC) to the hepatic side remains a difficult problem for diagnostic imaging.

Sentinel lymph node biopsy in patients with breast cancer using superparamagnetic iron oxide and a magnetometer

BackgroundSome hospitals lack facilities for radioisotopes in sentinel node biopsy. A novel method is used with a superparamagnetic tracer and a magnetometer instead of a radioisotope.MethodsThirty patients were included in the study after obtaining IRB approval. Superparamagnetic iron oxide and patent blue dye were injected in the subareolar breast tissue. Following a few minutes of massage to promote migration of the iron tracer and blue dye throughout the lymphatic vessels, the axillary lymph nodes were detected transdermally using a handheld magnetometer and followed by standard axillary dissection in all patients.ResultsOf 30 patients evaluated, sentinel lymph nodes were identified in 90% (27/30) using both blue dye and magnetic tracer. Sentinel lymph nodes were identified using the magnetic method in 23/30 (77%) and blue dye in 24/30 (80%). There was one false-negative sentinel node, resulting in an overall sensitivity of 6/7 (86%).ConclusionsThis is the first study to use a magnetic tracer to identify sentinel lymph nodes in patients with breast cancer. This new technique may alter the role of radioisotopes with further refinement and experience.

Pancreatic Complications in Choledochal Cyst and Their Surgical Outcomes

AbstractFollow-up results were analyzed to evaluate the surgical managements of pancreatic complications such as pancreatitis and protein plug formation in patients with choledochal cysts. Sixty-two patients with choledochal cysts treated between 1976 and 1999 were reviewed. Twenty-four were children and 38 were adults. Fifty-four patients showed primary cases. Cyst excision and hepaticoenterostomy were finally performed in 56 patients. Surgical sphincteroplasty or endoscopic sphincterotomy was performed to prevent recurrent protein plugs in six patients. The follow-up period was 8.1 ± 6.1 years. Acute pancreatitis and protein plug formation was observed in 18 (33.3%) and 11 (20.4%) of 54 patients showing primary cases, respectively. Both acute pancreatitis and protein plug formation were observed more frequently in children from 1 to 15 years of age (70.6% and 41.2%, respectively) than in adults (18.6% and 12.5%, respectively). Acute pancreatitis and/or protein plug formation developed in four (57.1%) of seven patients who underwent cystenterostomy. Protein plug formation in the residual cyst after cyst excision was observed in two patients, one of whom had undergone sphincteroplasty. Diabetes mellitus due to chronic pancreatitis developed in one patient who was diagnosed late. No other pancreatitis or protein plug recurred postoperatively in this series. Our results suggested that cystenterostomy did not resolve pancreatic complications of choledochal cysts, and that surgical sphincteroplasty was ineffective in preventing the recurrent protein plug formation in the residual duct. In conclusion, complete cyst excision and an early diagnosis are necessary to prevent the development of chronic or recurrent pancreatitis after surgery.

Prevalence of Synchronous Colorectal Neoplasms Detected by Colonoscopy in Patients with Gastric Cancer

PurposeOur purpose was to study the characteristics of colorectal neoplasms in patients with gastric cancer (GC).MethodsThe study group comprised GC patients who underwent colonoscopy before resection of their GC. We examined the prevalence, site, and histology of colorectal neoplasms, as well as the clinicopathological features and treatment of the patients who had synchronous colorectal cancers (CRC). The logistic regression model was applied to investigate the features of the GC patients with concurrent CRC.ResultsWe studied 466 GC patients (mean age 64.5 years; 147 women, 319 men), 143 (31%) of whom had a family history of gastrointestinal cancer. Synchronous colorectal adenoma and cancer were detected in 182 (39%) and 18 (4%) patients, respectively. Among the 18 synchronous CRCs, 11 were in the early stages and 10 of these were resected endoscopically. The other eight required simultaneous open radical surgery. All the GC patients with synchronous CRC were older than 50 years. Statistical analysis did not show a significant difference between the features of the patients with and those without concurrent CRC.ConclusionsThe possibility of synchronous colorectal neoplasms in GC patients cannot be disregarded in clinical practice; however, screening of the large bowel may not be necessary in GC patients younger than 50 years.

Diagnosis and treatment of pediatric patients with late-onset portal vein stenosis after living donor liver transplantation.

Portal vein stenosis (PVS) after living donor liver transplantation (LDLT) is a serious complication that can lead to graft failure. Few studies of the diagnosis and treatment of late‐onset (≥3 months after liver transplantation) PVS have been reported. One hundred thirty‐three pediatric (median age 7.6 years, range 1.3–26.8 years) LDLT recipients were studied. The patients were followed by Doppler ultrasound (every 3 months) and multidetector helical computed tomography (once a year). Twelve patients were diagnosed with late‐onset PVS 0.5–6.9 years after LDLT. All cases were successfully treated with balloon dilatation. Five cases required multiple treatments. Early diagnosis of late‐onset PVS and interventional radiology therapy treatment may prevent graft loss.