KRAS,NRAS, BRAF signatures,and MMR status in colorectal cancer patients in North China

We assessed the clinicopathological features and prognostic values of KRAS, NRAS, BRAF, and DNA mismatch repair status in colorectal cancer (CRC) to provide real-world data in developing countries. We enrolled 369 CRC patients and analyzed the correlation between RAS/BRAF mutation, mismatch repair status with clinicopathological features, and their prognostic roles. The mutation frequencies of KRAS, NRAS, and BRAF were 41.7%, 1.6%, and 3.8%, respectively. KRAS mutations and deficient mismatch repair (dMMR) status were associated with right-sided tumors, aggressive biological behaviors, and poor differentiation. BRAF (V600E) mutations are associated with well-differentiated and lymphovascular invasion. The dMMR status predominated in young and middle-aged patients and tumor node metastasis stage II patients. dMMR status predicted longer overall survival in all CRC patients. KRAS mutations indicated inferior overall survival in patients with CRC stage IV. Our study showed that KRAS mutations and dMMR status could be applied to CRC patients with different clinicopathological features.     

Guidelines for chemotherapy of biliary tract and ampullary carcinomas

Few randomized controlled trials (RCTs) with large numbers of patients have been conducted to date in patients with biliary tract cancer, and standard chemotherapy has not been established yet. In this article we review previous studies and clinical trials regarding chemotherapy for unresectable biliary tract cancer, and we present guidelines for the appropriate use of chemotherapy in patients with biliary tract cancer. According to an RCT comparing chemotherapy and best supportive care for these patients, survival was significantly longer and quality of life was significantly better in the chemotherapy group than in the control group. Thus, chemotherapy for patients with biliary tract cancer seems to be a significant treatment of choice. However, chemotherapy for patients with biliary tract cancer should be indicated for those with unresectable, locally advanced disease or distant metastasis, or for those with recurrence after resection. That is why making the diagnosis of unresectable disease should be done with greatest care. As a rule, pathological diagnosis, including cytology or histopathological diagnosis, is preferable. Chemotherapy is recommended in patients with a good general condition, because in patients with general deterioration, such as those with a performance status of 2 or 3 or those with insufficient biliary decompression, the benefit of chemotherapy is limited. As chemotherapy for unresectable biliary tract cancer, the use of gemcitabine or tegafur/gimeracil/oteracil potassium is recommended. As postoperative adjuvant chemotherapy, no effective adjuvant therapy has been established at the present time. It is recommended that further clinical trials, especially large multi-institutional RCTs (phase III studies) using novel agents such as gemcitabine should be performed as soon as possible in order to establish a standard treatment.     

Diagnosis of biliary tract and ampullary carcinomas

Diagnostic methods for biliary tract carcinoma and the efficacy of these methods are discussed. Neither definite methods for early diagnosis nor specific markers are available in this disease. When this disease is suspected on the basis of clinical symptoms and risk factors, hemato-biochemical examination and abdominal ultrasonography are performed and, where appropriate, enhanced computed tomography (CT) and/or magnetic resonance cholangiopancreatography (MRCP) is carried out. Diagnoses of extrahepatic bile duct cancer and ampullary carcinoma are often made based on the presence of obstructive jaundice. Although rare, abdominal pain and pyrexia, as well as abnormal findings of the hepatobiliary system detected by hemato-biochemical examination, serve as a clue to making a diagnosis of these diseases. On the other hand, the early diagnosis of gallbladder cancer is scarcely possible on the basis of clinical symptoms, so when this cancer is found with the onset of abdominal pain and jaundice, it is already advanced at the time of detection, thus making a cure difficult. When gallbladder cancer is suspected, enhanced CT is carried out. Multidetector computed tomography (MDCT), in particular — one of the methods of enhanced CT — is useful for decision of surgical criteria, because MDCT shows findings such as localization and extension of the tumor, and the presence or absence of remote metastasis. Procedures such as magnetic resonance imaging, endoscopic ultrasonography, bile duct biopsy, and cholangioscopy should be carried out taking into account indications for these procedures in individual patients. However, direct biliary tract imaging is necessary for making a precise diagnosis of the horizontal extension of bile duct cancer.     

Stenting and interventional radiology for obstructive jaundice in patients with unresectable biliary tract carcinomas

Together with biliary drainage, which is an appropriate procedure for unresectable biliary cancer, biliary stent placement is used to improve symptoms associated with jaundice. Owing to investigations comparing percutaneous transhepatic biliary drainage (PTBD), surgical drainage, and endoscopic drainage, many types of stents are now available that can be placed endoscopically. The stents used are classified roughly as plastic stents and metal stents. Compared with plastic stents, metal stents are of large diameter, and have long-term patency (although they are expensive). For this reason, the use of metal stents is preferred for patients who are expected to survive for more than 6 months, whereas for patients who are likely to survive for less than 6 months, the use of plastic stents is not considered to be improper. Obstruction in a metal stent is caused by a tumor that grows within the stent through the mesh interstices. To overcome such problems, a covered metal stent was developed, and these stents are now used in patients with malignant distal biliary obstruction. However, this type of stent has been reported to have several shortcomings, such as being associated with the development of acute cholecystitis and stent migration. In spite of these shortcomings, evidence is expected to demonstrate its superiority over other types of stent.     

Triple carcinomas of the biliary tract associated with congenital choledochal dilatation and pancreaticobiliary maljunction

We report a rare case of triple carcinomas of the biliary tract associated with congenital choledochal dilatation (CCD) and pancreaticobiliary maljunction (PBM). The patient was a 58-year-old Japanese man who complained of epigastralgia. Ultrasonography and computed tomography revealed an elevated lesion inside the markedly dilated extrahepatic bile duct, thickening of the gallbladder wall, and small polypoid lesions in the gallbladder. Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography showed CCD and PBM. With a diagnosis of carcinoma of the bile duct and cholesterol polyps in the gallbladder, pylorus-preserving pancreaticoduodenectomy was performed. The resected specimen showed two elevated lesions in the dilated bile duct, cholesterol polyps, and an area of irregular mucosa in the gallbladder. Histopathological examination showed two carcinomas in the bile duct, an adenosquamous cell carcinoma, and a moderately differentiated tubular adenocarcinoma, and a well differentiated tubular adenocarcinoma of the gallbladder. Two years and 6 months after the operation, a solitary metastatic liver tumor was detected. Left hepatic lobectomy was performed. At present, 7 months after the second operation, the patient is doing well with no signs of recurrence. Multiple carcinomas in the biliary tract associated with CCD and PBM, including the details in the present patient, were reviewed. Received: March 31, 1999 / Accepted: October 22, 1999     

High serum concentrations of sialyl Tn antigen in carcinomas of the biliary tract and pancreas

Sialyl-Tn (STn) antigen is a cancer-associated carbohydrate antigen expressed in cancers of the digestive tract. In the present study, we compared the serum level of STn antigen in 14 patients with benign diseases of the biliary tract and pancreas, 15 patients with bile duct cancers, and 9 patients with cancer of the pancreas. High levels of serum STn (>45 U/ml) were frequently detected in patients with carcinoma of the biliary tract (53.3%) or pancreas (55.6%), compared with the detection of high levels in those with benign diseases (14.3%;P < 0.05). Serum levels of STn did not correlate with the presence of jaundice, cholangitis, or pancreatitis, or with the level of carcinoembryonic antigen (CEA) or carbohydrate antigen (CA) 19–9. In cancer tissues, the expression of STn antigen detected by immunostaining correlated significantly with serum STn (P < 0.05). Our results indicate that measurement of serum STn level may be potentially useful for the diagnosis of carcinomas of the biliary tract and pancreas, particularly when combined with other tumor markers such as CEA or CA19-9.     

Poor prognosis of KRAS or BRAF mutant colorectal liver metastasis without microsatellite instability

Background

The discovery of practical biomarkers is important to realize personalized medicine for patients with malignant neoplasias, including colorectal cancer (CRC).

Purpose

The aim of this study was to determine reliable prognostic biomarkers by the analysis of patients with resectable colorectal liver metastases (CRLM).

Methods

Genomic DNA was obtained from the CRLM tissues of a cohort of 126 patients with CRLM with curative hepatic resection. The KRAS/BRAF mutation spectrum and microsatellite instability (MSI) status were successfully analyzed in 100 of the 126 CRLM tissues and these findings were examined in relation to the patients’ clinical outcomes.

Results

The cohort of 100 CRLM patients consisted of 46 with synchronous and 54 with metachronous liver metastasis. Overall survival and disease-free survival at 5 years were 57.4 and 24.9 %, respectively. MSI analysis revealed that none of the 100 CRLM specimens showed any evidence of MSI. By KRAS/BRAF mutation analysis, the analyzed CRLM patients were divided into 3 groups; KRAS-mutant (KRAS-Mt; n = 27), BRAF-mutant (BRAF-Mt; n = 3), and wild-types of both genes (Wild-type; n = 70). In the survival analysis, both KRAS-Mt and BRAF-Mt patients showed significantly poorer prognoses compared with Wild-type patients. Furthermore, although the population with the BRAF mutation was small, this mutation had a significant negative impact on disease-free survival.

Conclusions

In this study, all tumors in the cohort of CRLM patients were non-MSI tumors, suggesting MSI cancer in primary CRC would rarely reveal metastatic potential. KRAS and BRAF mutations are suggested to be poor prognostic factors in CRLM. Genetic information has an essential role as a prognostic marker and could contribute to the decisions on treatment strategy for CRLM.     

Flowcharts for the management of biliary tract and ampullary carcinomas

No strategies for the diagnosis and treatment of biliary tract carcinoma have been clearly described. We developed flowcharts for the diagnosis and treatment of biliary tract carcinoma on the basis of the best clinical evidence. Risk factors for bile duct carcinoma are a dilated type of pancreaticobiliary maljunction (PBM) and primary sclerosing cholangitis. A nondilated type of PBM is a risk factor for gallbladder carcinoma. Symptoms that may indicate biliary tract carcinoma are jaundice and pain in the upper right area of the abdomen. The first step of diagnosis is to carry out blood biochemistry tests and ultrasonography (US) of the abdomen. The second step of diagnosis is to find the local extension of the carcinoma by means of computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), percutaneous transhepatic cholangiography (PTC), and endoscopic retrograde cholangiopancreatography (ERCP). Because resection is the only way to completely cure biliary tract carcinoma, the indications for resection are determined first. In patients with resectable disease, the indications for biliary drainage or portal vein embolization (PVE) are checked. In those with nonresectable disease, biliary stenting, chemotherapy, radiotherapy, and/or best supportive care is selected.     

CD98 is a promising prognostic biomarker in biliary tract cancer

CD98 has been described to play a crucial role in tumor progression and survival. However, the role of CD98 in biliary tract cancer remains unclear. We found that 36.7% of all patients with biliary tract cancer had a high CD98 expression. Statistical analysis using Spearman's rank correlation showed that CD98 was significantly correlated with L-type amino acid transporter 1 (LAT1, r=0.562, P<0.001), Ki-67 (r=0.230, P=0.006) and CD34 (r=0.290, P=0.005). Multivariate analysis confirmed that a high CD98 expression was an independent prognostic factor for predicting poor outcome. CD98 is closely associated with tumor growth, biological aggressiveness, and survival of patients. With these data we proposed that CD98 expression is necessary for the development and pathogenesis of biliary tract cancer.(Hepatobiliary Pancreat Dis Int 2014;13:654-657)     

Long-term survival of patients with biliary tract cancers with lymph node involvement

In extrahepatic biliary tract malignancies, the prognostic value of lymph node involvement remains unclear. For a total of 161 tumors of the gallbladder (GBC) and bile duct (BDC) resected between 1982 and 1992, the number and extent of metastatic nodes were investigated according to the location of the primary tumor. In GBCs and upper two-third BDCs, more than half of node-positive tumors involved multiple nodes (58% and 63%), and node-positive tumors were associated with a significantly poorer rate of patient survival compared with node-negative tumors. However, GBCs with one or two nodes involved resulted in a longer survival time than those with three or greater (P = 0.0045). In lower one-third BDCs, even patients with node-positive tumors showed a 60% 5-year survival rate. There were 15 long-term survivors (i.e., survived for more than 5 years after surgery) with node-positive tumors in the GBC group, 4 in the upper BDC group, and 6 in the lower BDC group. Thirteen GBCs had one or two involved nodes, and 12 of the 13 GBCs positive nodes were located within the hepatoduodenal ligament. In upper and lower BDCs, pericholedocal nodes and nodes around the pancreatic head respectively, were most frequently involved. We concluded that lymphatic spread is an important prognostic determinant in both GBCs and upper BDCs. The prognosis of GBCs is especially influenced by the number of nodes involved. In lower BDCs, lymphatic metastasis does not necessarily preclude long-term survival.     

Preoperative biliary drainage for biliary tract and ampullary carcinomas

We posed six clinical questions (CQ) on preoperative biliary drainage and organized all pertinent evidence regarding these questions. CQ 1. Is preoperative biliary drainage necessary for patients with jaundice? The indications for preoperative drainage for jaundiced patients are changing greatly. Many reports state that, excluding conditions such as cholangitis and liver dysfunction, biliary drainage is not necessary before pancreatoduodenectomy or less invasive surgery. However, the morbidity and mortality of extended hepatectomy for biliary cancer is still high, and the most common cause of death is hepatic failure; therefore, preoperative biliary drainage is desirable in patients who are to undergo extended hepatectomy. CQ 2. What procedures are appropriate for preoperative biliary drainage? There are three methods of biliary drainage: percutaneous transhepatic biliary drainage (PTBD), endoscopic nasobiliary drainage (ENBD) or endoscopic retrograde biliary drainage (ERBD), and surgical drainage. ERBD is an internal drainage method, and PTBD and ENBD are external methods. However, there are no reports of comparisons of preoperative biliary drainage methods using randomized controlled trials (RCTs). Thus, at this point, a method should be used that can be safely performed with the equipment and techniques available at each facility. CQ 3. Which is better, unilateral or bilateral biliary drainage, in malignant hilar obstruction? Unilateral biliary drainage of the future remnant hepatic lobe is usually enough even when intrahepatic bile ducts are separated into multiple units due to hilar malignancy. Bilateral biliary drainage should be considered in the following cases: those in which the operative procedure is difficult to determine before biliary drainage; those in which cholangitis has developed after unilateral drainage; and those in which the decrease in serum bilirubin after unilateral drainage is very slow. CQ 4. What is the best treatment for postdrainage fever? The most likely cause of high fever in patients with biliary drainage is cholangitis due to problems with the existing drainage catheter or segmental cholangitis if an undrained segment is left. In the latter case, urgent drainage is required. CQ 5. Is bile culture necessary in patients with biliary drainage who are to undergo surgery? Monitoring of bile cultures is necessary for patients with biliary drainage to determine the appropriate use of antibiotics during the perioperative period. CQ 6. Is bile replacement useful for patients with external biliary drainage? Maintenance of the enterohepatic bile circulation is vitally important. Thus, preoperative bile replacement in patients with external biliary drainage is very likely to be effective when highly invasive surgery (e.g., extended hepatectomy for hilar cholangiocarcinoma) is planned.     

Identification of EGFR and KRAS mutations in Chinese patients with esophageal squamous cell carcinoma

The prognosis of esophageal squamous cell carcinoma (ESCC) is poor. It is urgent to improve this situation. Epidermal growth factor receptor (EGFR)‐targeted therapy possesses a promising clinical efficacy. Mutations of EGFR and V‐Ki‐ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) have been identified in esophageal carcinoma, but corresponding Chinese data are limited. So we investigated the mutation status of EGFR and KRAS in Chinese patients with ESCC, and explored their correlations with clinicopathological features. Formalin‐fixed paraffin‐embedded surgically resected tumor samples were obtained from 50 randomly selected Chinese patients with ESCC. EGFR mutations in exons 18–21 were detected by Scorpions amplification refractory mutation system technology. KRAS mutations in codons 12, 13 were detected by direct sequencing of polymerase chain reaction products. The correlations between clinicopathological features and the mutation status of EGFR and KRAS were analyzed using the Statistical Package for the Social Sciences. In the present study, EGFR mutations were found in 7 (14%) out of 50 patients, including G719X missense mutation (n= 1), in‐frame deletion (n= 2), and L858R missense mutation (n= 5). Six (12%) out of 50 patients had KRAS mutations in codon 12. Concurrent EGFR and KRAS mutations were detected in one sample. The presences of EGFR and KRAS mutations were not associated with gender, age, smoking history, cell differentiation, or cancer stage. In conclusion, the incidence of EGFR mutations in Chinese patients with ESCC was higher than that of previous reports, and the incidence of KRAS mutations was not low. EGFR and KRAS mutations were mainly located in exons 19 and 21 and codon 12, respectively. Unlike in NSCLC, concurrent EGFR and KRAS mutations existed.     

Guidelines for the management of biliary tract and ampullary carcinomas: surgical treatment

The only curative treatment in biliary tract cancer is surgical treatment. Therefore, the suitability of curative resection should be investigated in the first place. In the presence of metastasis to the liver, lung, peritoneum, or distant lymph nodes, curative resection is not suitable. No definite consensus has been reached on local extension factors and curability. Measures of hepatic functional reserve in the jaundiced liver include future liver remnant volume and the indocyanine green (ICG) clearance test. Preoperative portal vein embolization may be considered in patients in whom right hepatectomy or more, or hepatectomy with a resection rate exceeding 50%–60% is planned. Postoperative complications and surgery-related mortality may be reduced with the use of portal vein embolization. Although hepatectomy and/or pancreaticoduodenectomy are preferable for the curative resection of bile duct cancer, extrahepatic bile duct resection alone is also considered in patients for whom it is judged that curative resection would be achieved after a strict diagnosis of its local extension. Also, combined caudate lobe resection is recommended for hilar cholangiocarcinoma. Because the prognosis of patients treated with combined portal vein resection is significantly better than that of unresected patients, combined portal vein resection may be carried out. Prognostic factors after resection for bile duct cancer include positive surgical margins, especially in the ductal stump; lymph node metastasis; perineural invasion; and combined vascular resection due to portal vein and/or hepatic artery invasion. For patients with suspected gallbladder cancer, laparoscopic cholecystectomy is not recommended, and open cholecystectomy should be performed as a rule. When gallbladder cancer invading the subserosal layer or deeper has been detected after simple cholecystectomy, additional resection should be considered. Prognostic factors after resection for gallbladder cancer include the depth of mural invasion; lymph node metastasis; extramural extension, especially into the hepatoduodenal ligament; perineural invasion; and the degree of curability. Pancreaticoduodenectomy is indicated for ampullary carcinoma, and limited operation is also indicated for carcinoma in adenoma. The prognostic factors after resection for ampullary carcinoma include lymph node metastasis, pancreatic invasion, and perineural invasion.     

循环 microRNAs 在肝胆胰肿瘤发生发展中的作用

微小 RNA（miRNAs）参与机体的生长发育及疾病的病理生理过程,尤其在肿瘤性疾病的发生发展过程中起到致瘤基因或抑瘤基因的作用,另外全身血液循环中存在与特定肿瘤组织相应的循环 miRNAs。总结了近年来国内外研究发现的与肝胆胰肿瘤相关的循环 miRNAs,并分别阐述了 miRNAs 在肝胆胰肿瘤的诊断、临床病理分型、治疗及预后方面的应用价值。提出循环 miRNAs有望成为临床肿瘤筛查、诊断、治疗以及预后评价的新的生物标志物。