The role of past oral contraceptive use in the development of breast cancer is unclear, particularly in postmenopausal women. The authors investigated this relationship among pre-and postmenopausal middle-aged women in a nested case-control study within the population-based DOM cohort, Utrecht, the Netherlands. Among a total population of 12,184 women followed up for an average of 7.5 years, 309 breast cancer cases aged 42 to 63 years, diagnosed from November 1982 through May 1996, and 610 controls were examined. Overall, duration of oral contraceptive use was not clearly related to breast cancer. In women older than 55 years, however, oral contraceptive use for more than 10 years was associated with a 2-fold increased risk of breast cancer (odds ratio (OR) 2.1, 95% confidence interval (CI) 1.1-4.0). We conclude that long duration of oral contraceptive use increases the risk of breast cancer in women over 55 years of age but not in younger women.

Cognitive control is a mental process, which underlies adaptive goal-directed decisions. Previous studies have linked cognitive control to electrophysiological fluctuations in the u band and u-g cross-frequency coupling (CFC) arising from the cingulate and frontal cortices. However, to date, the behavioral consequences of different forms of u-g CFC remain elusive. Here, we studied the behavioral effects of the u-g CFC via transcranial alternating current stimulation (tACS) designed to stimulate the frontal and cingulate cortices in humans. Using a double-blind, randomized, repeated measures study design, 24 healthy participants were subjected to three active and one control CFC-tACS conditions. In the active conditions, 80-Hz g tACS was coupled to 4-Hz u tACS. Specifically, in two of the active conditions, short g bursts were coupled to the delivered u cycle to coincide with either its peaks or troughs. In the third active condition, the phase of a u cycle modulated the amplitude of the g oscillation. In the fourth, control protocol, 80-Hz tACS was continuously superimposed over the 4-Hz tACS, therefore lacking any phase specificity in the CFC. During the 20 min of stimulation, the participants performed a Go/NoGo monetary reward-based and punishment-based instrumental learning task. A Bayesian hierarchical logistic regression analysis revealed that relative to the control, the peak-coupled tACS had no effects on the behavioral performance, whereas the trough-coupled tACS and, to a lesser extent, amplitude-modulated tACS reduced performance in conflicting trials. Our results suggest that cognitive control depends on the phase specificity of the u-g CFC.

Currently, there is no established occupational risk factor for prostate cancer. However, in the 1980s, a hospital-based case-control study in the greater Dortmund area showed an elevated risk for hard coal miners and, based on few cases, for painters and varnishers. Therefore, approximately 10 yr later, a similar study regarding prostate cancer was performed in this area. In total, 292 patients with prostate cancer who underwent radical prostatectomy and 313 controls who underwent transurethral resection of a benign prostatic hyperplasia were investigated by questionnaire. All of them were operated on between 1995 and 1999. This study showed a decreased risk for prostate cancer in hard coal miners (odds ratio [OR] = 0.67, 95% confidence interval [CI] = 0.44-1.03). Occupational exposures related to an elevated risk for prostate cancer were exposures to combustion products (20% cases vs. 11% controls), colorants and dyes (19 vs. 13%), and cutting fluids (8 vs. 6%). The different prostate cancer risks for underground coal miners in two studies with a time interval of approximately 10 yr are striking. Factors to be discussed are the introduction of prostate-specific antigen (PSA) screening for prostate cancer and investigation of cases that underwent radical prostatectomy, where the disease in general is locally confined. Working conditions in the local underground coal mines improved over time but did not change markedly in the period of interest. In essence, the present study does not corroborate an elevated prostate cancer risk in former underground hard coal miners from the greater Dortmund area.

This study was performed to investigate the frequency of bladder cancer in patients with an occupational history such as underground hard coal mining and/or painting after the structural change in the local industry. A total of 206 patients with bladder cancer and 207 controls were enlisted regarding occupational and nonoccupational bladder cancer risk factors by questionnaire. The phase II enzymes N-acetyltransferase 2 (NAT2), glutathione S-transferases M1 (GSTM1), and T1 (GSTT1) and the single nucleotide polymorphism (SNP) rs11892031[A/C] reported to be associated with bladder cancer in genome-wide association studies were genotyped. The bladder cancer risk in varnishers and underground hard coal miners was increased as previously shown in a study in this area performed in the 1980s. The occupation of a car mechanic was associated with a significantly elevated bladder cancer risk and higher in the case of underground hard coal miners even though the mine was closed in 1987. The frequency of GSTM1 negative genotype was comparable in cases and controls (53% versus 54%). In the case of NAT2, the slow NAT2 genotype was more frequent (62% versus 58%) and ultra-slow NAT2 genotype (NAT2*6A and/or *7B alleles only) was 23% versus 15%. An occupational history of a varnisher or an underground hard coal miner remains a risk factor for bladder cancer occurrence. Data indicate that in the case of bladder cancer, GSTM1 is a susceptibility factor related to environmental and/or occupational exposure.