Breast Cancer
Nutrition Care

Cancer Nutrition Care (CNC) oncology dietitians have found that breast cancer patients tend to have a lot of questions about what to eat, what not to eat, and what supplements to take. Many are ready to put a plan into place, and take action, but don’t always know what to do or where to start.

CNC oncology dietitians have the specialized training and experience to address breast cancer diet and nutrition questions. Having oncology nutrition experience and access to critical evidence-based cancer nutrition information is key. CNC dietitians can competently provide for the comprehensive needs of breast cancer patients throughout their cancer treatment and into post-treatment survivorship.

Cancer patients who work with dietitians that have oncology nutrition experience have improved overall outcomes, quality-of-life, and a better patient experience. *

Breast Cancer Overview

Breast cancer mainly affects women but can also affect men. It occurs when breast tissue cells grow uncontrollably. Breast cancers can be classified as either ductal carcinomas, which start in the ducts, or lobular carcinomas, which start in the lobule glands. About 80% of all breast cancers are invasive ductal carcinomas which are also referred to as infiltrating ductal carcinomas. The words “invasive” and “infiltrating” refer to the fact the cancer cells have spread to the surrounding tissue.

Breast Cancer Nutrition and Diet

There are three major breast cancer subtypes: ER-positive, HER2-positive, and Triple Negative breast cancer. Each of these subtypes play into the patient’s broader prognosis, treatment prescriptions, and nutrition care planning. ER-positive and HER2-positive are the two most common breast cancer diagnoses and where cancer cell “receptors” are involved in the growth and spread of the disease. In the third subtype, Triple Negative breast cancer, which is actually a variety of different breast cancer types, cell receptors don’t play a role in the spread of the disease. Let’s dig deeper into the three subtypes:

1. ER-positive Breast Cancer and Nutrition Care

ER-positive breast cancer, also known as hormone receptor-positive breast cancer, is the most common type of breast cancer. This type of breast cancer has receptors that bind with either estrogen or progesterone, both naturally occurring hormones in the body. It is these hormones that are responsible for the growth and spread of the cancer cells. One class of hormone therapies, also known as endocrine therapies, is designed to interfere with the ability of estrogen and progesterone to bind to cancer cells. Another class of therapies reduces the body’s ability to produce estrogen and progesterone.

ER-positive breast cancer treatments can help stop or slow the rate of cancer cell growth, but in the process of doing this could have an impact on a patient’s nutrition status. For example, some prescribed treatments can affect healthy cells in the body resulting in unwanted side effects. These are often referred to as “nutrition impact symptoms”. Some undesirable nutrition impact symptoms from ER-positive therapies include, but are not limited to:

  • Weight Changes
  • Insomnia & Irritability
  • Diarrhea/Constipation
  • Nausea/vomiting
  • Fatigue
  • Taste & Flavor Alterations
  • Mouth Sores
  • Poor Appetite & Early Satiety

Some ER-positive treatment side effects can be managed through dietary means and lifestyle changes. Cancer Nutrition Care oncology dietitians can help develop a breast cancer specific nutrition plan of action so patients and their caregivers are prepared to work through the many issues that may arise. Given the fact that some breast cancer patients are prescribed hormone therapy medications for several years, it’s important to have a well thought out, evidence-based plan.

2. HER2-Positive Breast Cancer and Nutrition Care

The second most common type of breast cancer is called “HER2-positive breast cancer”. HER2 is a protein molecule found on the surface of all breast cells. It is this protein that is directly involved in the growth of HER2+ breast cancer. Many HER2+ cancers are also ER-positive which can create more nutrition related issues as these patients receive treatments that target both receptor subtypes. For this reason, and others, HER2+ breast cancer can be more complex to manage due to the multitude of nutrition impact symptoms that may arise. Common HER2+ nutrition impact symptoms include:

  • Elevated Liver Enzymes
  • Diarrhea/Constipation
  • Nausea/Vomiting
  • Fatigue
  • Low Red Blood Cell (RBC) Count
  • Low White Blood Cell (WBC) Count- which may increase the risk of infection
  • High Blood Pressure
  • Weight Changes
  • Taste & Flavor Alterations

Some HER2+ treatment side effects can be managed through dietary means and lifestyle changes. Cancer Nutrition Care oncology dietitians can help develop a plan of action so patients and their caregivers are prepared. With a HER2+ diagnosis it is important to have a detailed, comprehensive, evidence-based nutrition plan of care to manage the variety of potential side effects that may occur.

3. Triple-Negative Breast Cancer & Nutrition Care

The third subtype is called “Triple-negative breast cancer”. Triple Negative breast cancer does not involve molecular receptors, like the other two subtypes. “Triple Negative” is not a clinical diagnosis, per se, but more of a determination that the cancer cells have not responded to lab tests for estrogen receptors (ER), progesterone receptors (PR), or the hormone epidermal receptor 2 (HER2). About 10% to 20% of breast cancers fall into this third subtype, which is more likely to occur in younger people (and those with a BRCA1 gene mutation). Without the receptor proteins playing a role, Triple-Negative breast cancer can not only be more difficult to treat, but also more aggressive making the overall prognosis worse compared to the two other subtypes. Some common Triple Negative nutrition impact symptoms from treatment regimen(s) may include:

  • Elevated Liver Enzymes
  • Diarrhea/Constipation
  • Nausea/Vomiting
  • Fatigue
  • Low Red Blood Cell (RBC) Count
  • Low White Blood Cell (WBC) Count- which may increase the risk of infection
  • High Blood Pressure
  • Weight Changes
  • Taste & Flavor Alterations

Although treatments may be limited at this time, researchers are continuing to investigate new medications and therapies through a variety of clinical trials to address this particular type of breast cancer. No matter what the course of therapy, staying adequately nourished and hydrated will provide your body the best chance to tolerate treatments, heal, and recover.

4. Other Types of Breast Cancer

Cancer Nutrition Care Dietitians can support all breast cancer tumor types and diagnoses, even rare types. Rare forms of breast cancer include ductal carcinoma in situ, inflammatory and metaplastic breast cancer, and Paget disease.

Breast Cancer & Dietary Supplements

The American Institute for Cancer Research, and other well-regarded, evidence-based cancer organizations, do not support the use of supplements for breast cancer patients for treatment prevention or survivorship. Instead, it is advisable to focus on optimizing one’s diet to ensure adequate nutrient intake is consumed as opposed to relying on high dose, single nutrient, dietary supplements. However, there may be times when dietary supplements could play a valuable role in a patient’s care plan if they’re being prescribed to target a specific medical condition, such as a nutrient deficiency.

One of the concerns is that various supplements may actually interfere with chemotherapy regimens, radiation, and hormonal therapy treatments or simply be unsafe. Always make sure your medical team is aware of any supplements you may be using, or plan to take. Cancer Nutrition Care (CNC) Oncology Dietitians are Board Certified Specialists and have access to reliable information sources to help you learn more about supplement safety, benefit claims, and potential interactions with your prescribed treatment regimen. Take the first step by going to www.cancernutritioncare.com and completing the CNC Supplement Review. Once completed, please read through the CNC Supplement ToolBox resource to learn more regarding the use and safety of supplements within the oncology space.

Breast Cancer: In-Treatment Nutrition Support

Breast Cancer treatment consists of both “local” and “systemic” therapies. Local treatments target tumors directly and consist of surgery and radiation therapy. Systemic treatments look to impact cancer cells anywhere in the body. The main categories of systemic breast cancer treatments are chemotherapy, hormone therapy and immunotherapy. An oncologist may recommend one or multiple therapies to treat and/or manage a breast cancer diagnosis.

Treatment recommendations often take the patient’s condition into consideration since higher treatment doses can be more difficult to tolerate. This is what makes nutrition status so critically important.

Breast Cancer Surgery & Nutrition Care
Surgical options can include procedures such as lumpectomies, mastectomies, and lymph node dissections. There may also be breast reconstruction surgery to consider. Breast cancer surgery may be recommended as the only treatment or in conjunction with other therapies. Like any treatment intervention, patients preparing for (and coming out of) surgery should anticipate greater nutrition needs. In most cases, a temporary increase in calorie and protein intake is required to help in the healing and recovery processes. The additional calories could come from foods high in heart-healthy fats like nuts, seeds, and avocados. Additional protein requirements could come from some of those same foods (nuts & seeds) as well as healthy plant-based protein sources like beans and lentils.
Breast Cancer Radiation Therapy & Nutrition Care
Radiation therapy may be recommended as an accompaniment to other treatments like surgery or chemotherapy, or as the sole treatment. One of the most common side effects from breast cancer radiation is fatigue. There may also be an increased risk of esophagitis if the patient’s tumor is located close to the midline of the body. Esophagitis is inflammation of the esophagus which can cause painful swallowing as food & fluids pass from the mouth to the stomach. Dietary modifications to help with this may include eating softer, moister foods and relying on more liquid-based meals such as smoothies, pureed soups, and meals softened with sauces, broths, and gravies.
Breast Cancer Chemotherapy & Nutrition Care
Chemotherapy treatment leverages pharmaceutical products that are typically given in cycles. They are administered intravenously and/or orally. The toxicity of various chemotherapy agents not only destroys cancer cells but, unfortunately, healthy cells too. For this reason, it is imperative to increase one’s nutritional intake in preparation for treatment, during treatment and for post-treatment healing. The additional nutrient demand supports the critical bodily processes involved in healing and recovery. As with other therapies, chemotherapy patients should anticipate an increased energy demand and plan to consume more calories and protein to prevent any unintentional loss in weight. Weight loss can be problematic and lead to more serious conditions such as malnutrition.

Chemotherapy regimens are also notorious for causing a variety of nutrition related side effects. These can include nausea, vomiting, diarrhea, mouth sores, taste changes, poor appetite, and early satiety. CNC oncology dietitians can assist in preparing for an upcoming course of chemotherapy as well as healing from prior cycles. CNC dietitians can also help create a personalized nutrition care plan to help manage current, and potential, nutrition related side effects.

Breast Cancer Hormone Therapy, Immunotherapy, and Nutrition Care
Hormone therapy and immunotherapy, unlike the breast cancer therapies mentioned above, normally don’t require added calories and protein in the diet. These therapies can still come with their own potential list of nutrition-related side effects however. As always, it’s highly recommended that oncology patients work with their healthcare team to manage any nutrition impact symptoms in order to optimize treatment outcomes. CNC oncology dietitians have experience working with cancer care teams and can help create personalized cancer nutrition care plans to minimize the impact of side effects.

Breast Cancer: Post-Treatment Nutrition Support

Following the completion of treatment, breast cancer survivors’ emphasis on healthy eating, regular physical activity, and adoption of other healthy lifestyle factors could help reduce the chances of cancer recurrence and other cancers from forming. Developing post-treatment goals and a plan of action is advisable and highly recommended by organizations like the Commission on Cancer. CNC oncology dietitians recommend patients prioritize the following three areas following cancer treatment:

1. Healthy Weight Management

As per the American Institute for Cancer Research (AICR), maintaining a healthy weight is an important goal for breast cancer survivors. Proper weight management may help lower one’s risk for cancer recurrence, progression, and the development of other types of cancer. Excess amounts of fatty tissue can cause an inflammatory state for the body which could promote cancer in otherwise healthy cells. Additionally, being overweight or obese can increase certain hormone levels and encourage the growth of various hormone related cancers, such as breast cancer. Emerging research suggests that metabolic changes associated with weight gain may also promote breast cancer progression.

2. Plant Based Diet

Oncology nutrition research suggests that consuming whole plant-based foods can lower your cancer risk. This appears to be due to the regular intake of fiber, antioxidants, and phytochemicals. Nutrition research continues to evolve but findings to date suggest that consuming a whole food, plant-based diet can be an effective approach to maintaining a healthy weight. Dietary elements that should be limited, or eliminated completely, include red meat, processed meats, and alcohol. Cancer Nutrition Care oncology dietitians can review your specific dietary goals and develop an individualized nutrition plan of action to best meet your needs. Take the first step today by going to www.cancernutritioncare.com and completing the CNC Quality of Diet Screening to evaluate the current quality of your diet.

3. Routine Physical Activity

Cancer research in the area of physical activity indicates that exercise may reduce breast cancer risk.
Studies have found that physically inactive women are more likely to develop breast cancer, compared with active women. Physical activity may also decrease breast cancer recurrence, improve cancer‐specific (and overall) survival rates, quicken recovery from treatment side effects, and prevent long‐term side effects. Other exercise related intervention studies that looked at the impact of physical activity among cancer survivors show that exercise can improve fatigue, anxiety, depression symptoms, self‐esteem, happiness, and overall quality of life. Cancer Nutrition Care can refer you to an oncology fitness specialist to help you set goals and put together an action plan.

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