The purpose of this study is to determine if a high dose of DHA begun prior to and continued during neo-adjuvant chemotherapy (chemotherapy given prior to surgery) is likely to prevent or lessen chemotherapy induced cognitive dysfunction.

Chemotherapy is often associated with problems of cognitive functioning such as decision making, learning, and memory. These symptoms, collectively referred to here as cognitive dysfunction can appear as early as the first few months after starting chemotherapy and may persist long after chemotherapy and anti-hormone therapy, if any, is completed.

Once developed there is no satisfactory treatment for cognitive dysfunction although cognitive retraining and exercise may improve symptoms and/or function; at least for some.

Omega-3 fatty acids derived from ocean fish are a new potential preventative treatment against development of cognitive problems which can arise in some individuals during chemotherapy treatment. In doses of 1-2 grams per day it has been found to improve some aspects of cognitive function in healthy adults who have low DHA dietary intake. It has also been shown to improve some aspects of function in individuals with a mild reduction in cognitive ability but not for those with marked impairment.

Participation in this study will last about 12 months. Participants will make visits to the study site for both standard of care visits and additional study-related visits. Participants will be randomized (randomly assigned; like flipping a coin) to one of two groups. Neither the Investigator nor the participant will know the assigned treatment.

Inclusion Criteria:

• Diagnosis of invasive breast cancer (Stage I-III) and are anticipated to start neo-adjuvant chemotherapy (multiple chemotherapy regimens allowed under protocol)
• Able to read, write, and understand English and at least have a high school education.
• Able and willing to go at least 24-36 hours without narcotic pain medicine, muscle relaxants, sedatives, sleeping pills and alcohol prior to their cognitive testing. Participants should not have required chronic sedatives, sleeping aids, or narcotic pain medications on a daily basis prior to their diagnosis.
• Willing to complete required study procedures from start of study to approximately 6 months after completion of neo-adjuvant chemotherapy.

Exclusion Criteria:

• Women who are currently on omega-3 fatty acid supplements with > 500 mg of EPA plus DHA daily or 250 mg of DHA alone and or who have chronically been on more than 1 fish oil capsule per day.
• Individuals who are not willing to stop fish or krill oil supplements during the study.
• Diabetics requiring insulin treatment.
• Individuals who are not likely to be able to go for 24 hours without sleeping pills, sedatives, narcotic pain medications, or ativan
• Individuals who do not have a high school education or are not fluent in English.
• Individuals who have already started chemotherapy for breast cancer or who have previously had systemic chemotherapy for a malignancy.
• Women who have already had definitive surgery for breast cancer.

Global results will be published.