It is often helpful to classify biomarker values into groups of different risk levels to facilitate evaluation of a biological, physiological, or pathological state. Stratification of patients into two risk groups is commonly seen, but there is always need for more than two groups for fine assessment. So far, there are no standard methods or tools to help decide how many cutoff points are optimal. In this study, we developed a comprehensive package that included methods to determine both the optimal number and locations of cutoff points for both survival data and dichotomized outcome. We illustrated workflow of this package with data from 797 patients with cervical cancer. By analyzing several risk factors of cervical cancer such as tumor size, body mass index (BMI), number of lymph nodes involved and depth of stromal invasion, in relation to survival and clinical outcome such as lymph nodal metastasis and lymphovascular invasion, we demonstrated that the best choice for BMI and stromal invasion was two cutoff points and one for the others. This study provided a useful tool to facilitate medical decisions and the analyses on cervical cancer may also be of interest to gynecologists. The package can be freely downloaded.

Chiang AJ, et al. J Gynecol Oncol. 2017 Dec;29:e28. https://doi.org/10.3802/jgo.2018.29.e28

Cardiovascular disease is the leading cause of morbidity and mortality in patients with end‐stage renal disease who undergo hemodialysis and endothelial dysfunction is an early key step in the development of atherosclerosis. The aim of this study was to investigate the effect of thrice‐weekly in‐center nocturnal hemodialysis (INHD, 8 h per session and three sessions per week) and conventional hemodialysis (CHD, 4 h per session and three sessions per week) on endothelial dysfunction in patients with end‐stage renal disease. 32 INHD and 58 matched CHD patients were enrolled, baseline and 12‐month measures of blood pressure (BP), serum calcium and phosphorus, serum intact PTH (iPTH) and brachial artery flow‐mediated dilation (FMD) were collected and analyzed. Baseline characteristics were similar between groups except that serum phosphorus and calcium × phosphorus were higher in the INHD group. At the 12‐month follow‐up, there was a significant increase in FMD (6.0 ± 1.5% to 7.1 ± 1.8%, P < 0.01) in INHD patients. Multivariate analysis showed that FMD was inversely correlated with systolic BP (SBP) (β = −0.485, P < 0.01), diastolic BP (DBP) (β = −0.428, P < 0.01), iPTH (β = −0.405, P < 0.01) and serum phosphorus level (β = −0.375, P < 0.01). There was no significant change in FMD in the CHD group. Compared with CHD, INHD improves endothelial function, and control of serum phosphorus is associated with the improvement of endothelial function.

Aims: To develop a new package of joint model to fit longitudinal CA125 in epithelial ovarian cancer relapse. Patients & methods: Included were 305 epithelial ovarian cancer patients who reached complete remission after cytoreductive surgery and first-line chemotherapy. Univariate and multivariate analysis with a joint model was performed to select independent risk factors, which were subsequently combined to predict recurrence. Results: Independent factors were longitudinal CA125, age, stage and residual tumor size (p < 0.05). Prediction of recurrence with these factors had an average of 80.7% accuracy, 5.6–10.7% better than kinetic factors. Conclusion: The new package of joint model fits longitudinal CA125 well. Potential application can be extended to other biomarkers.