Kim SH, et al. J Gastric Cancer. 2010 Dec;10(4):149-154. http://dx.doi.org/10.5230/jgc.2010.10.4.149

The prevalence of hemorrhoids has been reported to be 7-14%. However, there have been no large-scale studies. This study aims to investigate the incidence of hemorrhoids in Korea by analyzing big data and to find the associated risk factors. This was a retrospective analysis using the Health Insurance Cohort database of the National Health Insurance Corporation of Korea in 2002-2015. The study was divided into two models: the diagnostic (DM) and surgical model (SM). Socio-demographic and lifestyle behavioral characteristics were analyzed as risk factors. Overall, 467,567 participants were included. The incidence density of hemorrhoids was 13.9 and 5.7 per 1000 person-years in the DM and SM, respectively. Hemorrhoids occurred more frequently in men and metropolitan areas in both models. The incidence was highest in the 40s. The incidence rates were highest in the high income, smoking, alcohol and the exercise group of 1-4 times a week in both models. The adjusted hazard ratio (HR) was higher in men and decreased with increasing age. It was higher in the metropolitan area. The high-income level and alcohol consumption were risk factors in the DM and SM, respectively. The HR of the exercise group was higher than that of the non-exercise group in both models. The diagnostic and surgical incidence density was 13.9 and 5.7 per 1000 person-years, respectively. Hemorrhoids occurred most frequently in men in their 40s. The metropolitan area, high income level and alcohol consumption were associated with an increased frequency of hemorrhoids.

Loss of Smad4 function is associated with the acquisition of advanced colorectal cancer phenotypes. We investigated the role of Smad4 as a prognostic marker after curative therapy. Four hundred and twenty nine consecutive colorectal cancers were analyzed by tissue microarray-based immunohistochemical assay. Smad4 protein was expressed in 61.5% (24/39), 53.1% (77/145), 41.3% (78/189) and 34.8% (16/46) of stage I, II, III and IV cancers, respectively. Lymphovascular invasion and lymph node metastasis were strongly correlated with the loss of Smad4 expression (p<0.0001 and p=0.002, respectively). Disease-free survival did not differ between Smad4-positive and Smad4-negative cancers. In stage III disease, time to recurrence after curative therapy was shorter in the Smad4-negative than in the Smad4- positive cancers (20.1±15.1 vs. 34.6 ± 34.1 months, p=0.035). Smad4 protein is of no value in predicting recurrence after curative therapy in colorectal cancer, but it may be helpful in identifying a subset of patients with early recurrence after curative therapy.