Female Breast Cancer Is Now the No. 1 Cancer Diagnosis Worldwide
What’s New For the first time, female breast cancer has surpassed lung cancer as the most commonly diagnosed cancer type in the world, according to a report published in the February 4 issue of CA: A Cancer Journal for Clinicians. Research Details The American Cancer Society and the International Agency for Research on Cancer investigators examined incidence and mortality data for 36 cancers across 185 countries based on age and sex. Findings showed female breast cancer topping the list as the most commonly diagnosed cancer, representing 11.7 percent of all cancers (2.3 million new cases), followed by lung (11.4 percent), colorectal (10.0 percent), prostate (7.3 percent), and stomach (5.6 percent) cancer. Although lung cancer remained the leading cause of cancer deaths (18 percent, or approximately 1.8 million deaths), breast cancer accounted for 6.9 percent of cancer deaths in women. Why It Matters Report findings highlight that without major preventive efforts, cancer incidence is expected to rise in developed nations by as much as 56 percent by 2040. While some of this increase is due to a growing and aging population, researchers say that rates might be “further exacerbated by an increasing prevalence of risk factors in many parts of the world.” Some breast cancer risk factors (family history and age, for example) can’t be changed, but certain steps can be taken to lower risk, including weight control, limiting alcohol intake, regular exercise, and breast cancer screening. RELATED: New Treatment for Aggressive Breast Cancer Announced at ESMO 2020
Study Links Increased Thyroid Cancer Risk to Outdoor Lighting
What’s New Greater exposure to outdoor artificial lighting (lighting at night, or LAN) appears to be associated with higher incidence of thyroid cancer in middle-aged to older U.S. adults, according to a study published online in February’s Cancer journal. Research Details Study findings were based on data from 464,371 adults enrolled in the National Institutes of Health-AARP Diet and Health Study, plus satellite imagery of estimated LAN levels at each participant’s home address. Participants exposed to the highest LAN levels had a 55 percent greater risk for developing thyroid cancer. This link was more than threefold stronger for the most common type of thyroid cancer (papillary) and almost fivefold stronger in women compared with men. Women were also more likely to develop localized cancer versus more advanced disease. Why It Matters The link between light pollution and health is due to its effect on melatonin, according to a report issued by the National Optical Astronomy Observatory. Study researchers concur and write that LAN in particular “suppresses melatonin.” Disruptions in melatonin can disturb the body’s circadian rhythm (i.e., the body’s internal clock) as well as the balance of hormones that influence and maintain normal thyroid function (e.g., estrogen). Previous studies have also linked these factors to elevated thyroid cancer risk. RELATED: Cancer News Update: Acupuncture Helps Cancer-Related Pain, Thyroid Cancer on the Decline, and More
Novel Breast Cancer Screening Strategy Focuses on Dense Breasts
What’s New Researchers propose a breast cancer screening strategy that establishes a baseline breast density at age 40 and then uses this measure to determine how often women should undergo mammography. The findings, which were published in the February 9 online edition of Annals of Internal Medicine, suggest that this approach may help reduce breast cancer deaths. Research Details Researchers compared outcomes of seven breast cancer screening strategies using a mathematical model. Establishing a baseline breast density at age 40, followed by annual mammography between ages 40 and 75 for women with dense breasts, and biennially (every two years) starting at age 50 for women with non-dense breasts would reduce deaths from breast cancer by roughly 35 percent. On the flip side, it also increased the likelihood for false-positive results (incorrectly diagnosing breast cancer when it’s not present) by roughly fourfold, as well as overdiagnosis rates by roughly 6 percent. Why It Matters Dense breast tissue affects about half of women under age 50 and can make it difficult to spot cancers on mammograms. It also increases the risk for developing cancer, namely because the cells in the glands making up the dense breast tissue tend to divide frequently, leading to mistakes or mutations. Women who’ve been told that they have dense breasts might wish to speak to their doctors about the best screening strategy for their needs, especially since other factors, like age or medical history, may also influence overall risk. RELATED: Dense Breasts 101: What You Need to Know if You Have This Type of Breast Tissue
New Drug Class Increases Survival in Bladder Cancer
What’s New A new drug class known as ADC (antibody-drug conjugate) appears to significantly increase survival in patients with advanced bladder cancer, according to a study published in The New England Journal of Medicine. Research Details Six hundred and eight patients across 19 countries with locally advanced or metastatic bladder cancer received the ADC drug Padcev or chemotherapy for roughly five months. All had previously received chemotherapy and immunotherapy. The findings showed that ADC reduced the risk of death by 30 percent, adding roughly 13 months to overall survival time. What’s more, participants taking the ADC agent experienced 5.6 months without progression of their cancer versus 3.7 months for patients on chemotherapy. Why It Matters ADCs represent a new, targeted bladder cancer treatment that attaches to cancer cells to deliver a chemotherapy-like drug while ignoring normal, healthy cells. Study findings add to the evolving information about ADCs and are welcome news for patients who have had limited options and survival. RELATED: Kidney and Bladder Cancer Breakthroughs Among Top ESMO 2020 News
Test Helps to Determine if Breast, Ovarian Cancer Genes Predict Malignant Disease
What’s New Mayo Clinic researchers have developed a method that determines the clinical importance of BRCA2 gene variants of uncertain significance (VUS), according to study findings published in the February 19 issue of the American Journal of Human Genetics. Research Details Some mutations on the BRCA genes are known to increase the risk for cancer, while other variations of the mutations have yet to be tied to certain risk. The study team, in this case, was the first to be able to discriminate between BRCA2 variants that were known to cause cancer and those that were known to be benign, using a functional test. The test allowed researchers to reclassify 86 percent of VUS with uncertain outcomes as likely to progress to cancer (pathogenic) or as benign in 1,900 participants. Why It Matters Until now, the ability to detect variants has outpaced the ability to assess their clinical relevance, challenging counseling and management of patients and their relatives, note the researchers. With this new approach, patients will be able to learn if their breast or ovarian cancer VUS are benign or pathogenic. In an accompanying press release, coauthor Fergus Couch, PhD, said that women whose VUS are benign will “now be evaluated on personal/family history and not on the basis of genetic testing,” while “patients who are classified as having pathogenic variants will be able to benefit from more frequent cancer screenings or prophylactic mastectomy” to reduce breast cancer risk. He also said that the approach will allow women with ovarian cancer to learn if they qualify for targeted therapy. RELATED: Is There Sex After Ovarian Cancer?