New research on cancer, nutrition and walking
September 1, 2018
Daily fruit and vegetable intake matters
Eating five or more servings of fruits and vegetables a day may make a bigger difference than previously recognized. A new study has found that women who eat a high amount of fruits and vegetables each day may have a lower risk of breast cancer compared to women who eat fewer fruits and vegetables.
Researchers from Harvard T.H. Chan School of Public Health found that cruciferous vegetables such as broccoli, and yellow and orange vegetables, had a particularly significant association with lower breast cancer risk. Previous work by this research group linked reduced breast cancer risk with higher fiber intake, but the benefits of fruits and vegetables found in this study appear to be independent of their fiber content.
“Although prior studies have suggested an association, they have been limited in power, particularly for specific fruits and vegetables and aggressive subtypes of breast cancer,” said study author Maryam Farvid, who is a research scientist in the Department of Nutrition at Harvard. “This research provides the most complete picture of the importance of consuming high amounts of fruit and vegetables for breast cancer prevention.”
The researchers analyzed diet questionnaires submitted every four years by participants in the Nurses’ Health Study (88,301 women, starting in 1980) and the Nurses’ Health Study II (93,844 women, starting in 1991). They found that women who ate more than 5.5 servings of fruits and vegetables each day had an 11 percent lower risk of breast cancer than those who ate 2.5 or fewer servings. A serving is defined as one cup of raw leafy vegetables, half a cup of raw or cooked vegetables, or half a cup of chopped or cooked fruits.
To find out whether the benefits of fruit and vegetable consumption differed among various types of breast cancers, the researchers conducted an analysis by tumor hormone receptor status and molecular subtype. They found that higher consumption of fruits and vegetables was particularly associated with lower risk of more aggressive tumors including ER-negative, HER2-enriched, and basal-like tumors.
Walking away from heart disease
Adults in their early 60s, who spend less time sitting and more time engaged in light to vigorous physical activity, benefit with healthier levels of heart and vessel disease markers, according to British researchers. Physical inactivity is a well-known risk factor for cardiovascular disease and premature death from cardiovascular disease.
“The 60 to 64 age range represents an important transition between work and retirement, when lifestyle behaviors tend to change,” said study investigator Ahmed Elhakeem, who is a senior research associate in epidemiology at Bristol Medical School, University of Bristol in the United Kingdom. “It may therefore be an opportunity to promote increased physical activity.”
The researchers found it’s important to replace time spent sedentary with any intensity level of activity. They studied more than 1,600 British volunteers, age 60 to 64, who wore heart rate and movement sensors for five days. The sensors revealed how much physical activity they were doing. They measured light physical activity, such as slow walking, stretching, golfing or gardening, versus moderate-to-vigorous activity, such as brisk walking, bicycling, dancing, tennis, squash, lawn mowing or vacuuming.
New blood test may predict optimal treatment for advanced prostate cancer
Researchers at Memorial Sloan Kettering Cancer Center in New York City are reporting they have developed a blood test that can predict how men with advanced prostate cancer will respond to specific treatments. They hope this blood test will help improve survival rates.
The team has successfully tested a liquid biopsy test that examined circulating tumor cells (CTCs) in blood samples from men with advanced prostate cancer who were deciding whether to switch from hormone-targeting therapy to chemotherapy. CTCs are cancer cells that leave a tumor and enter the blood stream and invade other parts of the body.
The new test identifies whether or not a patient’s CTCs contain a protein called AR-V7 in the cell’s nucleus. The research team set out to determine whether the presence of this protein predicted which treatment would best prolong survival. They found that patients who tested positive for the protein responded best to taxane-based chemotherapy while those who tested negative for the protein responded best to hormone-targeting therapy with drugs called androgen-receptor signaling (ARS) inhibitors. These are the two most widely used drug classes to treat advanced prostate cancer.
The researchers conducted a study with 142 patients who had already undergone at least one round of hormone-targeting therapy without success and were working with their oncologist to decide whether to switch to a different hormone-targeting therapy or to chemotherapy as their next line of treatment. While this study looked at predicting the best treatment for patients who had already undergone at least one round of hormone-targeting therapy, a future goal of the team is to assess this test or similar CTC blood tests in determining optimal therapy at earlier decision points in advanced prostate cancer care. The team also plans to evaluate different versions of the CTC blood test for other types of cancer, such as lung cancer.
John Schieszer is an award-winning national journalist and radio and podcast broadcaster of The Medical Minute. He can be reached at email@example.com.