Water Man

The painting Children’s Story (Water Dreaming by Two Children) by Native Australian artist Johnny Warangkula Tjupurrula (1925-2001) and Thomas Cole comments appeared in Art of JAMA.  Life in the arid Northern Territory is difficult and is sustained on meager amounts of water found in locations well hidden and known only to the indigenous people who have survived for millennia by keeping the locations of water to themselves.  The Water Man depicted in this painting is important for survival as he knows where to find water in remote wells, caves, and soaks. He used mental maps known as songlines to find water in the desert. By repeating the words of a song or the movements of a dance, indigenous Australians could follow routes and find landmarks in the open country. Indigenous Australians believed that songlines have been existed thru eternity, a concept referred to as the dreamtime.

Breast Density should not be the Sole Criterion in Determining High Risk for Breast Cancer

Research by Kerlikowske et al published in the Annals of Internal Medicine suggests that not all women with dense breasts are at high enough risk for breast cancer after a normal mammogram to justify having more diagnostic tests such as ultrasound or MRI.

The researchers used data from Breast Cancer Surveillance Consortium (BCSC) breast imaging facilities.

Studies of 365 426 women aged 40 to 74 years who had 831 455 digital screening mammographic examinations were reviewed.

BI-RADS breast density, BCSC 5-year breast cancer risk, and interval cancer rate (invasive cancer ≤12 months after a normal mammography result) per 1000 mammography examinations. High interval cancer rate was defined as more than 1 case per 1000 examinations.

High interval cancer rates were observed for women with 5-year risk of 1.67% or greater and extremely dense breasts or 5-year risk of 2.50% or greater and heterogeneously dense breasts (24% of all women with dense breasts). The interval rate of advanced-stage disease was highest (>0.4 case per 1000 examinations) among women with 5-year risk of 2.50% or greater and heterogeneously or extremely dense breasts (21% of all women with dense breasts). Five-year risk was low to average (0% to 1.66%) for 51.0% of women with heterogeneously dense breasts and 52.5% with extremely dense breasts, with interval cancer rates of 0.58 to 0.63 and 0.72 to 0.89 case per 1000 examinations, respectively.

In this study half of women had mammograms that showed dense breasts. For most women who had a mammogram, the risk for breast cancer after a normal mammogram was low, even for those who had dense breasts and low 5-year breast cancer risk. Two groups of women had the highest risk for breast cancer after a normal mammogram: those with extremely dense breasts and an intermediate or high 5-year cancer risk, and those who had different patterns of breast density and a high or very high 5-year cancer risk.

Breast density should not be the sole criterion for deciding whether supplemental imaging is justified because not all women with dense breasts have high interval cancer rates. BCSC 5-year risk combined with BI-RADS breast density can identify women at high risk for interval cancer.

MRI Scans May Predict A Woman’s Future Risk Of Developing Breast Cancer

Research by Dontchos et al published in Radiology suggests that MRI of the breast may predict a woman’s future risk of developing breast cancer.  They looked whether qualitative magnetic resonance imaging (MRI) assessments of background parenchymal enhancement (BPE), amount of fibroglandular tissue (FGT), and mammographic density are associated with risk of developing breast cancer in women who are at high risk.

They reviewed all screening breast MRI studies obtained from January 2006 to December 2011 in women aged 18 years or older and at high risk for but without a history of breast cancer. Women in whom breast cancer was diagnosed after index MR imaging comprised the cancer cohort, and one-to-one matching (age and BRCA status) of each woman with breast cancer to a control subject was performed by using MR images obtained in women who did not develop breast cancer with follow-up time maximized. Amount of BPE, BPE pattern (peripheral vs central), amount of FGT at MR imaging, and mammographic density were assessed on index images.

Twenty-three women at high risk (mean age, 47 years ± 10 [standard deviation]; six women had BRCA mutations with no history of breast cancer underwent screening breast MR imaging; in these women, a diagnosis of breast cancer (invasive, n = 12; in situ, n = 11) was made during the follow-up interval. Women with mild, moderate, or marked BPE were nine times more likely to receive a diagnosis of breast cancer during the follow-up interval than were those with minimal BPE. BPE pattern, MR amount of FGT on MRI, and mammographic density were not significantly different between the cohorts.

Greater background parenchymal enhancement (BPE) was associated with a higher probability of developing breast cancer in women at high risk for cancer and warrants further study.

USPSTF guidelines for breast cancer screening

On April 20, 2015, the U.S. Preventive Services Task Force (USPSTF) released its draft guidelines for breast cancer screening.

The USPSTF recommends biennial screening mammography for women ages 50 to 74 years.

The decision to start screening mammography in women prior to age 50 years should be an individual one. Women who place a higher value on the potential benefit than the potential harms may choose to begin biennial screening between the ages of 40 and 49 years.

•   For women at average risk for breast cancer, most of the benefit of mammography will result from biennial screening during ages 50 to 74 years. Of all age groups, women ages 60 to 69 years are most likely to avoid a breast cancer death through mammography screening. Screening mammography in women ages 40 to 49 years may reduce the risk of dying of breast cancer, but the number of deaths averted is much smaller than in older women and the number of false-positive tests and unnecessary biopsies are larger.

•   All women undergoing regular screening mammography are at risk for the diagnosis and treatment of noninvasive and invasive breast cancer that would otherwise not have become a threat to her health, or even apparent, during her lifetime (known as “overdiagnosis”). This risk is predicted to be increased when beginning regular mammography before age 50 years.

•   Women with a parent, sibling, or child with breast cancer may benefit more than average-risk women from beginning screening between the ages of 40 and 49 years.

•    The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening mammography in women age 75 years and older.

•     The USPSTF concludes that the current evidence is insufficient to assess the benefits and harms of tomosynthesis (3-D mammography) as a screening modality for breast cancer.

This recommendation applies to asymptomatic women age 40 years and older who do not have pre-existing breast cancer or a previously diagnosed high-risk breast lesion and who are not at high risk for breast cancer because of a known underlying genetic mutation (such as a BRCA mutation or other familial breast cancer syndrome) or a history of chest radiation at a young age.