• The Korean Journal of Applied Statistics
• /
• v.25 no.6
• /
• pp.947-958
• /
• 2012

When modeling event times in biomedical studies, the outcome might be incompletely observed. In this paper, we assume that the outcome is recorded as current status failure time data. Despite well-developed literature the routine practical use of many current status data modeling methods remains infrequent due to the lack of specialized statistical software, the difficulty to assess model goodness-of-fit, as well as the possible loss of information caused by covariate grouping or discretization. We propose a model based on pseudo-observations that is convenient to implement and that allows for flexibility in the choice of the outcome. Parameter estimates are obtained based on generalized estimating equations. Examples from studies in bile duct hyperplasia and breast cancer in conjunction with simulated data illustrate the practical advantages of this model.

• Journal of Digestive Cancer Research
• /
• v.3 no.2
• /
• pp.101-104
• /
• 2015

A 55-year-old man was admitted to the hospital for jaundice. Computed tomography (CT) scans showed a diffuse mass in the pancreas and peripancreatic area, with infiltration to of the whole pancreas, and overall reduced enhancement compared to normal pancreas. Esophagogastroduodenoscopy revealed elevated mucosal lesion covered hyperemic mucosa at duodenal bulb and ulcerative lesion at body of stomach. Endoscopic ultrasonography revealed an irregular mass with unclear boundaries was observed within the pancreas. Abrupt narrowing of mid to distal common bile duct was seen and the stricture was caused by compression of pancreatic mass. Plastic stent was inserted and clinical improvement was achieved including resolution of jaundice. The patient is currently being treated with combination of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone. We report a case of primary pancreatic lymphoma presenting with obstructive jaundice.

• The Korean Journal of Pancreas and Biliary Tract
• /
• v.22 no.4
• /
• pp.165-171
• /
• 2017

Background/Aim: There is little data on whether plastic stents with a larger diameter are patent for longer than small stents in patients with bile duct cancer. The aim of this study was to compare the stent survival between 7-French (Fr) and 10-Fr plastic stents and evaluate the factors affecting stent survival. Methods: Patients with biliary obstruction due to biliary tract cancer were enrolled at Yonsei University Wonju College of Medicine from January 2010 to October 2014. Results: A total of 215 patients (7-Fr:10-Fr = 89:126 patients) were retrospectively enrolled. The primary tumor sites were common bile duct (n = 111), hilar (n = 45), and ampulla of Vater (n = 59). Rates of stent migration and stent obstruction were not different between the two groups. The median duration of stent survival was 3.3 months in the 7-Fr group and 5.9 months in the 10-Fr group (p = 0.543). The diameter of the stent did not have an effect on stent survival (hazard ratio 1.11, 95% confidence interval 0.71-1.73, p = 0.649). Conclusions: 7-Fr and 10-Fr stents have similar rates of stent migration and stent obstruction. The stent survival of 7-Fr was not inferior to 10-Fr stents in the management of biliary tract cancer.

• Journal of Korean Neurosurgical Society
• /
• v.65 no.1
• /
• pp.57-63
• /
• 2022

Objective : To study the factors relating to operative treatment for spinal metastasis in Thailand during 2005-2014 and to determine the hospital costs, mortality rate, and incidence of perioperative complication. Methods : Inpatient reimbursement data from 2005 to 2014 was reviewed from three national healthcare organizations, including the National Health Security Office, the Social Security Office, and the Comptroller General's Department. The search criteria were secondary malignant neoplasm of bone and bone marrow patients (International Classification of Diseases 10th revision, Thai modification codes [ICD 10-TM], C79.5 and C79.8) who underwent spinal surgical treatment (ICD 9th revision, clinical modification procedure with extension codes [ICD 9-CM], 03.0, 03.4, 03.09, and 81.0) during 2005-2014. Epidemiology, comorbidity, and perioperative complication were analyzed. Results : During the study period, the number of spinal metastasis patients who underwent operative treatment was significantly increased from 0.30 to 0.59 per 100000 (p<0.001). More males (56.14%) underwent surgical treatment for spinal metastasis than females. The most common age group was 45-64 (55.1%). The most common primary tumor sites were the unknown origin, lung, breast, prostate, and hepatocellular/bile duct. Interestingly, the proportion of hepatocellular/bile duct, breast, and lung cancer was significantly increased (p<0.001). The number of patients who had comorbidity or in-hospital complication significantly increased over time (p<0.01); however, the in-hospital mortality rate decreased. Conclusion : During the last decade, operative treatment for spinal metastasis increased in Thailand. The overall in-hospital complication rate increased; however, the in-hospital mortality rate decreased.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.1
• /
• pp.87-90
• /
• 2012

Cholangiocarcinoma (CCA) is the most common cancer in northeastern Thailand. At present, effective diagnosis of CCA either in humans or animals is not available. Monitoring the development and progression of CCA in animal models is essential for research and development of new promising chemotherapeutics. Ultrasonography has been widely used for screening of bile duct obstruction in CCA patients. In this study, we preliminarily investigated the applicability of ultrasonography to monitor the development and progression of CCA in Syrian golden hamsters (n=8) induced by Opisthorchis viverrini (OV)/dimethylnitrosamine (DMN) administration. Ultrasonography and histopathological examination of hamsters was performed at week 0, 20, 24 and 28 of OV infection or at the start of water/Tween-80 administration to controls. The ultrasonographic images of liver parenchyma and gallbladders of OV/DMN-induced CCA hamsters showed sediments in gallbladder, thickening of gallbladder wall, and hypoechogenicity of liver parenchyma cells. The ultrasonographic images of liver tissues were found to correlate well with histopathological examination. Although ultrasonography does not directly detect the occurrence of CCA, it reflects the thickening of bile ducts and abnormality of liver tissues. It may be applied as a reliable tool for monitoring the development and progression of CCA in animal models in research and development of new promising chemotherapeutics for CCA.

• Journal of Preventive Medicine and Public Health
• /
• v.20 no.1 s.21
• /
• pp.84-96
• /
• 1987

For the purpose of preparing the basic data for further cancer epidemiologic study and cancer patients control, we conducted the analysis on the degree and structure of deaths from cancer in metropolitan areas of Korea with 7,934 certified cancer deaths records of Seoul, Pusan, Taegu and Incheon in 1982. The analyzed results were as follows: 1) The total number of cancer deaths in metropolitan areas were 7,934 (male: 4,749, female: 3,185) as 14.1% of deaths from all causes in the same area. 2) The rate of physician's certification on cancer deaths was 77.4% and most of cancer deaths (84.4%) occured at their home. 3) Cancer specific death rate was 51.7 per 100.000 population (male: 62.9, female: 41.9) and age-adjusted cancer death rate was 82.4 in male and 51.6 in female per 100,000 population. And the difference was statistically significant (p< 0.01). 4) Age-specific cancer death rate was generally increased with age and most of cancer deaths (male: 75% , female: 65%) occurred from 45 to 74 years old. 5) The first three orders of cancer site were stomach (32.7%), liver (28.8%), lung (11.7%) in male and stomach (30.6%), uterus (18.4%), liver (13.8%) in female. And the relative frequency of these three cancer sites among total cancer deaths was corresponded to 73.2% in male and 62.8% in female. 6) The ratio of male to female cancer death rate was 1.5:1. And the ratio was aboye 3.0 in esophagus, liver, larynx, bladder cancer and the ratio was similar to 1.0 in stomach, pancreas, leukemia, brain, colon cancer, but the ratio was reversed in gall bladder and bile duct, and thyroid cancer.

• Biomolecules & Therapeutics
• /
• v.25 no.5
• /
• pp.482-489
• /
• 2017

Individual differences in drug responses are associated with genetic and epigenetic variability of pharmacogene expression. We aimed to identify the relevant miRNAs which regulate pharmacogenes associated with drug responses. The miRNA and mRNA expression profiles derived from data for normal and solid tumor tissues in The Cancer Genome Atlas (TCGA) Research Network. Predicted miRNAs targeted to pharmacogenes were identified using publicly available databases. A total of 95 pharmacogenes were selected from cholangiocarcinoma and colon adenocarcinoma, as well as kidney renal clear cell, liver hepatocellular, and lung squamous cell carcinomas. Through the integration analyses of miRNA and mRNA, 35 miRNAs were found to negatively correlate with mRNA expression levels of 16 pharmacogenes in normal bile duct, liver, colon, and lung tissues (p<0.05). Additionally, 36 miRNAs were related to differential expression of 32 pharmacogene mRNAs in those normal and tumorigenic tissues (p<0.05). These results indicate that changes in expression levels of miRNAs targeted to pharmacogenes in normal and tumor tissues may play a role in determining individual variations in drug response.

• Radiation Oncology Journal
• /
• v.10 no.1
• /
• pp.49-58
• /
• 1992

From January 1985 to September 1990, 7 patients with carcinoma of the extrahepatic biliary system received external radiaiton therapy combined with hyperthermia. Of the 3 patients with extrahepatic bile duct cancer, two were primary cholangiocarcinoma and one was metastatic peripancreatic carcinoma. Of the 4 patients with carcinoma of the gallbladder, two were locor-egionally advanced and unresectable carcinoma and the remaining two were local-regional recurrence after cholecystectomy. They were all pathologicallly proven adenocarcinoma. The radiation dose received ranged from 3000 cGy/2weeks to 5040 cGy/7 weeks. The hyperthermia was done once or twice a week and 4 to 12 sessions in total. The tumor response was confirmed by T-tube cholangiography, percutaneous transhepatic cholangiography and CT scan. 6 out of 7 ($86\%$) showed partial regression of the tumor. The median survival time was 7 months (range $4\~11$ months).6 out of 7 patients were dead: one died of septicemia, 4 of primary disease, one of distant metastases. Only one out of 7 patients is still alive but new metastatic lesion was found. There was not any treatment related deaths. There was also no evidence of treatment related problems with liver, stomach and duodenum, although the observation period was short.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.11
• /
• pp.5381-5384
• /
• 2012

Background and Aim: Cholangiocarcinoma (CCA) is an uncommon malignancy of the bile duct, occurring in nearly 2 out of 100,000 people. It is a type of adenocarcinoma that originates in the mucous glands of the epithelium, or surface layers of the bile ducts. The aim of this study was to evaluate the clinical features, diagnostic results and factors associated with survival, morbidity and mortalityof cholangiocarcinoma cases in Iranian patients. Method: In this retrospective study the hospital medical records of 283 patients with a primary or final diagnosis of cholangiocarcinoma who had been admitted to gastroenterology ward of our hospital from 2004 to 2011 were retrospectively reviewed. Results: 283 patients (180 male, 63%, and 103 female, 38.6%) with a mean age of $59.7{\pm}14.4$ years were studied. The most frequent symptoms were painless jaundice (190, 66.9%), abdominal pain (77, 27%), pruritus 133 (46.8%) and weight loss (169, 59.5%). The most frequent associated risk factors and diseases were as follows: gallstones (72, 25.4%), diabetes (70, 24.6%), HBV infection (52 (18.3%), HCV infection 43 (15%), primary sclerosing cholangitis (16, 5.6%) and smoking (120, 42.3%). The most frequent type of cholangiocarcinoma in ERCP and MRCP was hilar. The mean survival time was $7.42{\pm}5.76$ months. Conclusion: The mean survival time in our study was lower than one year. Moreover the most frequent risk factors and associated diseases were smoking, gallstones and diabetes. Painless jaundice, abdominal pain and weight loss were the most clinical features related to cholangiocarcinoma. Additionally survival time did not correlate with risk factors, associated diseases and clinical presentations, but was linked to biliary metallic stenting and surgery.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.5
• /
• pp.1737-1742
• /
• 2015

Background: Mitochondrial DNA (mtDNA) mutations have been shown to be associated with cancer. This study explored whether mtDNA mutations enhance cholangiocarcinoma (CCA) development in individuals. Materials and Methods: The whole mitochondrial genome sequences of 25 CCA patient tissues were determined and compared to those of white blood cells from the corresponding individuals and 12 healthy controls. The mitochondrial genome was amplified using primers from Mitoseq and compared with the Cambridge Reference Sequence. Results: A total of 161 mutations were identified in CCA tissues and the corresponding white blood cells, indicating germline origins. Sixty-five (40%) were new. Nine mutations, representing those most frequently observed in CCA were tested on the larger cohort of 60 CCA patients and 55 controls. Similar occurrence frequencies were observed in both groups. Conclusions: While the correspondence between the cancer and mitochondrial genome mutation was low, it is of interest to explore the functions of the missense mutations in a larger cohort, given the possibility of targeting mitochondria for cancer markers and therapy in the future.