This study aims to evaluate electroacupuncture as an antiemetic treatment compared with sham acupuncture in patients with breast cancer, receiving highly emetogenic chemotherapy (HEC). Moreover, it will analyze the association between single nucleotide polymorphism and the antiemetic outcomes of electroacupuncture.

This is a parallel-group, triple-blinded (participants, evaluators and statisticians), randomized controlled study that investigates the antiemetic role of electroacupuncture combined with standard antiemetic drugs for patients with breast cancer receiving HEC. Neurokinin-1 receptor antagonists (NK-1RAs), serotonin receptor antagonists [5HT3RA] and dexamethasone will be administered prior to initiation of HEC on Day 1 in both groups. Electroacupuncture or sham acupuncture will be randomly administered to the two groups. Subjects will record all events of emesis and the use of rescue antiemetic medication for nausea and/or vomiting. Blood samples will be collected and be analyzed to whether genetic polymorphisms can be used to predict Electroacupuncture outcomes in patients with breast cancer receiving HEC. Primary and secondary outcomes and adverse events will be evaluated.

Inclusion Criteria:

1. 18 years of age or older, of any nationality;
2. Eastern Cooperative Oncology Group performance status of 0-2;
3. For patients with breast cancer, molecular typing is not limited, receiving for the first time chemotherapy with anthracyclines+ cyclophosphamide (EC or AC) or carboplatin (AUC≥4)/cisplatin -based HEC regimen. Patients with previous chemotherapy use could be enrolled if they received it >3 months;
4. Predicted life expectancy of ≥3 months;
5. Adequate bone marrow, kidney, and liver function;
6. Adequate contraception if premenopausal women;
7. Written informed consent by the patient before enrolment.

Exclusion Criteria:

1. Patients already submitted to chemotherapy;
2. Is scheduled to receive any non-HEC on Day 1;
3. Received or is scheduled to receive radiation therapy to the abdomen, pelvis, head and neck within 1 week prior to Day 1 or between Days 1 to 5 in cycle 1;
4. Has symptomatic primary or metastatic symptomatic central nervous system malignancy causing nausea and/or vomiting;
5. Have ongoing emesis or CTCAE grade 2 or greater nausea;
6. Significant mental conditions;
7. Any allergies to study drug, antiemetics or dexamethasone;
8. Significantly abnormal laboratory values (platelets, absolute neutrophils, AST, ALT, bilirubin or creatinine);
9. Patients who are pregnant or breast-feeding;
10. Inflammatory skin reaction;
11. Has lymphedema in acupuncture stimulation area;
12. Patients who are afraid of electroacupuncture stimulation or allergic to stainless steel needles;
13. Received acupuncture treatments for any conditions less than 4 weeks before HEC;
14. The current use of any drugs with antiemetic activity (e.g. 5-HT3 RA, dopamine receptor antagonist, minor tranquilizer, antihistamine);
15. Patients with concomitant severe diseases or with a predisposition to emesis such as gastrointestinal obstruction, active peptic ulcer, hypercalcemia and symptomatic brain metastasis;
16. Patients receiving other concomitant antiemetic treatments or submitted to antiemetic treatments in the 24 hours before chemotherapy;
17. Patients receiving concomitant steroids, except when administered at physiologic doses;
18. Patients receiving concomitant benzodiazepines, except when used for nocturnal sedation.