Supervised Exercise to Promote Infiltration of NK-cells Into the Tumor

This is a multicenter randomized controlled feasibility trial, in which 20 women with breast cancer scheduled for neoadjuvant 2 or 3 weekly AC-T(H) chemotherapy will be randomized into a combined aerobic and resistance exercise intervention group or a usual care (no exercise) control group, during the first 6 weeks (2 or 3 cycles) of chemotherapy. Patients from the control group will receive care as usual and are requested to maintain their usual daily physical activities. In order to limit contamination (increase of exercise in the control group), non-participation and prevent dropout, the control group will be offered the same 6-week exercise intervention after the tumor biopsy has been taken after 6 weeks.

Inclusion criteria

• stage I-III breast cancer
• scheduled for neoadjuvant chemotherapy with 2 or 3-weekly Adriamycin/Cyclofosfamide, followed by Paclitaxel weekly +/- trastuzumab
• willing to undergo an additional ultrasound guided biopsy
• ECOG-performance score ≤ 2 (able to perform basic activities of daily living such as walking or biking)

Exclusion criteria

• addition of immuno- or targeted therapy at start of neoadjuvant chemotherapy
• currently participating in structured vigorous aerobic exercise and/or resistance exercise

(≥2 days per week).

• cognitive disorder or severe emotional instability
• presence of other disabling co-morbidity that might hamper physical exercise e.g. heart failure (NYHA classes 3 and 4), chronic obstructive pulmonary disease (COPD, gold 3 and 4), orthopaedic conditions and neurological disorders (e.g., hernia, paresis, amputation, active rheumatoid arthritis);
• immunosuppressive medication (e.g. corticosteroids (other than used as part of standard chemotherapy premedication protocol), cyclosporine)
• immunodeficiency (primary or secondary)
• impossibility to perform an ultrasound-guided biopsy of the tumor