Latinas in the U.S. have lower rates of breast cancer than Caucasian women. One study reported that the rate of breast cancer is 35% lower among Latinas than in white women living in the San Francisco Bay Area. However, Latinas tend to have more aggressive disease and outcomes are less favorable. Latina breast cancer patients are approximately 20% more likely to die than white women during the first five years after diagnosis. This web page is designed to outline the differences between the two groups and how Latinas can influence their breast cancer risk and outcomes. As such, we will be focusing on risk factors that differ between the two groups. Variables such as physical activity, which appear to have similarly beneficial effects on breast cancer risk and prognosis for Latinas and non-Hispanic white women, will not be covered here.
Definition of Latina
For purposes of this website, by Latinas we mean women originating from Mexico, Central or South America, or the Caribbean who have at least some Native American, indigenous Mesoamerican, Native South American, or Native Caribbean ancestry. They may or may not retain some or all of the language, culture and traditional eating customs of their regions of origin. We will be focusing on the effects of intrinsic genetic factors and diet in this web page, rather than cultural factors and socioeconomic status. Recognizing that some Latinas identify as white, for purposes of this website, by white women we mean Caucasian women whose ancestors originated emigrated entirely or for the most part from Western Europe.
Differences in breast cancer between Latina and white women
There are genetic differences between Latinas and white women that translate into differences in breast cancer risk and survival. Generally speaking, the higher the proportion of Native American or other indigenous American ancestry, the lower the breast cancer risk. One study of women living in Mexico reported that those with 76% to 100% European ancestry had 2.4 times the risk of breast cancer as women with 0% to 25% European ancestry.
While Latinas are less likely to develop breast cancer than white women, they tend to do so at a younger age. One Mexican study of almost 700 breast cancer cases reported that 19% of the patients were 40 or younger at diagnosis compared to approximately 7% of U.S. breast cancer cases. This is one reason why screening mammograms should start at age 40 among Latinas, rather than at age 50 as has been suggested for relatively low-risk women.
Latinas are also more somewhat more likely to develop triple negative (ER-/PR-/HER2-) disease, an aggressive form of breast cancer. Various studies have reported that the prevalence of triple negative breast cancer is higher in Latinas than white women. One large joint California-Hawaii study reported that the rate of ER−/PR− breast cancer was 31% among African Americans, 25% among Latinas, and 18% among whites, Japanese and Native Hawaiians.
Latinas with triple-negative breast cancer should be tested for BRCA1 and BRCA2 mutations. One Mexican study reported that a BRCA mutation was found in 23% of patients with triple-negative breast cancer, most of which were BRCA1 mutations. Latinas are also at increased risk of second breast cancer regardless of ER/PR status of the first tumor. The presence of African ancestry also can contribute higher risk of triple negative breast cancer risk and worse outcomes. For more information, please see our article on the prognosis of African Americans and Latinas with triple negative breast cancer.
Acculturation increases breast cancer risk
U.S. acculturation tends to counteract some of the protection against breast cancer conferred by indigenous American ancestry. Hispanic immigrants typically exhibit an intermediate level of risk between those living in their birth country and those in the U.S., which is reflected in higher breast density in immigrants. This appears to be the result of adoption of dietary and lifestyle risk factors associated with acculturation.
Hormone replacement therapy (HRT)
Hormone replacement therapy (HRT) appears to be a stronger breast cancer risk factor among Latinas than white women. One large study that made the comparison reported that HRT use was associated with a 35% increase in risk in Hispanic women compared to a 20% increase in white women.
Although Latinas are less likely to drink alcoholic beverages than white women, there is evidence that Latinas are more vulnerable to alcohol's breast cancer promoting effects due to genetic factors. Alcohol intake tends to increase with acculturation. Alcohol drinking during the teenage years is a risk factor for subsequent breast cancer among white girls, especially those with a family history of breast cancer. Given the demonstrated vulnerability of Latinas to this risk factor, it is plausible that adolescent alcohol intake might also be particularly risky for Latinas.
High blood pressure
While there is some evidence that high blood pressure (hypertension) is a breast cancer risk factor in white women, the available evidence appears stronger among Latinas. One study of Chilean women reported that hypertension (define as blood pressure ≥ 140/90 mmHg) was significantly higher in women with breast cancer (37.1%) than in women without the disease (17.1%). In addition, hypertensive women had four-fold higher risk of breast cancer than non-hypertensive women. Even mild hypertension (130/85 to 140/90 mmHg) increased breast cancer risk.
Exposure to agricultural pesticides and chemicals
While pesticide residues on consumed fruits and vegetables have not been convincingly linked to risk of breast cancer, the far higher levels of exposure among farm workers or those living near farms are a risk factor. This appears to be because some currently approved pesticides possess endocrine disrupting properties, i.e., they interfere with hormone systems in the body. Girls appear to be more vulnerable than adult women.
Girls whose mothers worked in greenhouses in the first trimester of pregnancy have been found to have earlier breast development than girls without such prenatal exposure. Such early development is a breast cancer risk factor. Girls who are raised on or near farms, raised by farm workers, or who are themselves farm workers are especially vulnerable to the breast cancer-promoting effects of certain pesticides, hormones and other chemicals used in the production of food and other products. Girls should be kept out of harm's way when such chemicals are applied and should not be required to pick or process crops to which pesticides have been applied. For more information on how to protect our daughters from breast cancer, please see our articles on childhood and puberty and teenage years and young adulthood.
While not all crops are grown with the assistance of carcinogens, some crops are associated with particularly high rates of breast cancer among adult workers. For example, one study found that California mushroom workers had approximately six times the expected incidence of breast cancer. It is likely that exposure is higher when workers operate in enclosed places such as green houses and indoor mushroom farms.
Diet and breast cancer risk among Latinas
While Latinas come from a wide variety of culinary traditions, there are some foods and cooking methods that are common throughout Latin America. We have organized foods often found in such cuisines for which there is adequate information into those that have been found to be associated with reduced breast cancer risk ("Recommended") or increased risk ("Limit or avoid"). There are a number of foods, such as cassava, jicama and tamarind, for which there is essentially no information available in English. Other foods, such as chocolate, plantains and cumin, have been studied, but the effect of consuming the foods on breast cancer risk is unclear.
Foods to limit or avoid
The emphasis on peppers, fresh vegetables, and fruits in Latin American cooking is very favorable from the point of view of breast cancer risk and survival. However, some foods, dietary patterns and cooking methods could contribute to breast cancer risk and recurrence. One Argentinian study that grouped women according to common dietary patterns reported that a diet emphasizing fruit and non-starchy vegetables was protective against breast cancer. The diets associated with breast cancer risk were what the authors termed "Traditional" (fat meats, bakery products, vegetable oil and mayonnaise); "Rural" (processed meat); and "Starchy" (refined grains).
One Brazilian study reported that intakes of apples, watermelon and tomatoes were associated with reduced breast cancer risk. The same study reported that the consumption of lard and fatty red meat were linked to higher breast cancer risk. A Mexican study found that a high percentage of calories from carbohydrates, especially sugars, was associated with increased breast cancer risk.
Foods sourced from a Latina's country of origin can sometimes be less safe than foods produced in the U.S. For example, one study of corn products procured from Hispanic markets in San Diego, California, reported that zearalenone, an estrogenic mycotoxin produced by fungal infection, was found in 7 of 9 masa samples, 10 of 15 tortilla samples, and 4 of 10 fresh corn samples. Zearalenone can promote early puberty in young girls and abnormal hormone levels in women. Cultured oysters from parts of the southeast Gulf of California were found to have cadmium concentrations that exceeded the maximum level allowed by the Official Mexican Standard in another study. Cadmium is a known breast cancer risk factor.
Latinas can take steps to improve their breast cancer outcomes
As noted above, Latinas are less likely to survive breast cancer than Caucasian patients. Part of the explanation is that Latinas tend to have more aggressive types of breast cancer. However, there is some evidence that Latinas have worse outcomes even when they have more indolent, hormone-responsive disease. Delays and disparities in treatment are part of the explanation. Socioeconomic status and Spanish-only speaking can be important barriers to receiving optimal breast cancer care, even taking account insurance inequalities. Nevertheless, we offer the following advice to Latinas, who can take the following concrete steps to improve their outcomes, in addition to adopting a customized breast cancer diet:
- If at all possible, have your breast cancer care at a breast cancer center of excellence or the best cancer center in your local area. Some of these centers have translators and special programs for uninsured or otherwise disadvantaged women.
- Make your breast cancer treatment a priority in your life. You have to come first during this time. Do your best to complete every aspect of your treatment. Get the help that you need to do this from family, church and friends. Bring a fully fluent relative or friend to appointments, if necessary. Some states have special financial assistance programs specifically for breast cancer patients.
- Get a referral to a medical oncologist from the surgeon who performs your breast surgery as soon as possible and make the appointment immediately. Similarly, if it looks like you are going to need radiotherapy, get a referral to a radiation oncologist from your oncologist and make the first appointment as soon as possible. If faced with a long appointment delay, call back frequently to see if an appointment has opened up. The time between phases of treatment (surgery, chemotherapy, radiation, anti-estrogen treatment) should be measured in weeks, not months.
- Ask each physician that you see what treatment is standard for your type and stage of disease so that you can compare this to the treatment that is eventually offered.
- Make sure that your oncologist is aware of your commitment to treatment. Unfortunately, studies have found that Latina patients are less likely to keep appointments and complete treatment than white patients. Therefore, there might be a tendency on the part of some oncologists to assume that Latinas, especially those of low income, will not be able to undergo extensive treatment such as radiation. It's certainly unfair and may be awkward for you, but it could be important for you to communicate your ability to undergo treatment in order to be offered the best possible care for your situation.
- If you have a lumpectomy, it should be followed by radiation treatment. If you cannot participate in up to six weeks of daily radiation treatment, a mastectomy might be a better choice. Undergoing accelerated partial breast irradiation is another option that could reduce the number of appointments.
- If you have an aggressive form of breast cancer (triple negative, inflammatory breast cancer (IBC), HER2/neu overexpressing (HER2+), large tumor size, multiple positive lymph nodes, any breast cancer under age 45), you need aggressive treatment. This is likely to include chemotherapy. Even if he or she gives you a choice, your oncologist will have an opinion as to what would be best for you and will tell you if pressed. Make the tough choice.
- Have regular mammograms after you finish treatment according to the schedule your oncologist recommends. One study that tried to determine why Latinas are less likely than white women to survive breast cancer reported that lack of consistent post-diagnosis mammograms was the strongest driver of the survival disparity.
Please see our article on how to optimize your breast cancer diet for information on what to eat during all stages of treatment and recovery. Please also click on the tag Latinas for more articles and studies concerning Latinas and breast cancer.