Caan et al. Page 1260

Weight change after a breast cancer diagnosis has been linked to lower survival. To investigate this relationship, Caan and colleagues analyzed postdiagnostic weight variation and survival in breast cancer patients from the United States and China. They report that weight stability in the early years following diagnosis was associated with lower overall mortality risk. In the United States, lower survival was seen for women who lost weight after breast cancer diagnosis and had comorbid conditions. This report illuminates the importance of personalized weight control strategies for breast cancer survivors.

Demetriou et al. Page 1272

The field of cancer epidemiology has been criticized for producing false-positive associations. Demetriou and colleagues investigated the frequency of and factors contributing to false-positive findings in cancer epidemiology studies. The International Agency for Research on Cancer Monographs Group 3 agents were examined to identify potential false-positive findings, and frequency estimates for false-positive occurrences were calculated. Among 509 agents, only 37 were found to have potential false-positive associations. These results suggest that cancer epidemiology is not overwhelmed with false-positive findings. This study should help restore faith in epidemiologic procedures and validate epidemiologic findings as important tools to guide public health measures.

Kurta et al. Page 1282

Studies on the use of fertility drugs and ovarian cancer risk have produced conflicting results. Kurta and colleagues used data from the Hormones and Ovarian Cancer Prediction (HOPE) study to determine if fertility drug use has an impact on ovarian cancer risk, taking into account parity, gravidity, and cause of infertility. The authors report that ever use of fertility drugs was not significantly associated with ovarian cancer within the total HOPE population or among women who sought attention for infertility. These results suggest that fertility drug use does not significantly contribute to overall risk of ovarian cancer when adjustment is made for known confounding factors.

Koestler et al. Page 1293

Blood leukocytes from patients with solid tumors exhibit complex and distinct cancer-associated patterns of DNA methylation. Koestler and colleagues examined this by first identifying differentially methylated regions (DMR) in leukocytes from healthy control subjects. They then evaluated these leukocyte DMRs in patients with different cancers. They report that a substantial proportion of the most common leukocyte DMRs were differentially methylated to a statistically significant extent among head and neck squamous cell carcinoma cases and ovarian cancer cases, compared with cancer-free control subjects. These results suggest that leukocyte DMRs could represent powerful new diagnostic tools, applicable to a range of solid tumors.