Introduction:
The study investigated cardiopulmonary function in breast cancer patients versus healthy control women.

Methods:
Overall, 115 women after breast cancer surgery and 50 healthy controls were included. The outcome measures were spirographic and hemodynamic parameters.

Results:
Most of the investigated parameters in breast cancer patients were significantly lower than in healthy women. The actual vital capacity (VC) was significantly lower by 0.34 l (p < 0.001), forced vital capacity (FVC) by 0.25 l (p < 0.001), forced expiratory volume in 1 second (FEV1) by 0.26 l (p < 0.001), peak expiratory flow (PEF) by 0.95 l/s (p < 0.001), maximum expiratory flow25 (MEF25) by 0.98 l/s (p < 0.001), maximum expiratory flow50 (MEF50) by 0.65 l/s (p < 0.001), expiratory reserve volume by 0.48 l (p < 0.001), maximal voluntary ventilation by 22.73 l/min (p < 0.001). The percentage of predicted values of VC, FVC, FEV1, PEF, MEF25, and MEF50 was lower by 9.93% (p < 0.001), 7.39% (p < 0.001), 8.87% (p < 0.001), 15.7% (p < 0.001), 18.09% (p < 0.001), and 15.96% (p < 0.001), respectively. As for the cardiovascular system, the actual stroke volume was higher in the control group compared with the main group by 12.20 ml/beat (p < 0.001), stroke index by 8.85 ml/beat/m2 (p < 0.001), cardiac output by 0.87 l/min (p < 0.001), left ventricular work by 0.96 g · m/beat (p < 0.001), LVP by 0.26 W (p < 0.001).

Conclusions:
Cancer treatment negatively affected most cardiorespiratory parameters. The results support the need for physiotherapy intervention in breast cancer patients after treatment.