The disease presents a variety of disease spectrums from asymptomatic disease state to full-blown cirrhosis. The survival of PBC patients is long because of slow progression and early detection of the disease. Several studies have indicated that PBC may be associated with increased risks of some cancers, such as hepatocellular carcinoma (HCC), breast cancer, pancreatic cancer, and so forth.1-13 CP-673451 chemical structure If an increased risk for some malignancies can be proved, clinical management, surveillance, and follow-up issues will be carefully addressed. However, the results of

previous studies are controversial. The differences noted between the studies may be explained partially by the methodology, sample sizes, and so forth. To date, no published meta-analyses have successfully established the association of PBC with cancer risk. The aim of the present study was to perform a systematic review and meta-analysis to derive a better estimation of the association. CI, confidence interval; HCC, hepatocellular carcinoma; NOS, Newcastle-Ottawa Scale; PBC, primary NVP-BGJ398 ic50 biliary cirrhosis; PIR, proportional incidence ratio; RR, rate ratio; SIR, standardized incidence ratio. A literature search of the PubMed and EMBASE databases was conducted for English-language studies published before

November 2011 using combinations of the following terms: primary biliary cirrhosis and cancer; malignancy; malignancies; neoplasm; tumor; carcinoma; and lymphoma. All eligible articles MCE were retrieved, and their references were checked for other relevant studies. Studies were included in the meta-analysis if they fulfilled the following inclusion criteria: (1) cohort or case-control design;

(2) PBC as one of the exposure interests; (3) cancer as one of the outcome of interests; (4) rate ratio, hazard ratio, or standardized incidence ratio with 95% confidence intervals (CIs) (or with data to calculate them) available; and (5) independent study. In case of multiple reports on the same population or subpopulation, we included only data from the latest or complete studies with the largest numbers of cases and controls. Studies were excluded if the effect size could not be calculated according to these studies. When studies provided more than one rate ratio (RR) according to the duration of PBC before malignancy was diagnosed, the RRs for individuals diagnosed with PBC more than 1 year prior to the diagnosis of malignancy were extracted and combined. Quality assessment was performed using the Newcastle-Ottawa Scale (NOS).14 There are a total of eight items in the NOS categorized into three dimensions: selection, comparability, and—depending on the study type—outcome (cohort) or exposure (case-control). A star system of the NOS has been developed for the assessment.