The Impact of Breast-Conserving Therapy and Radiotherapy on Respiratory Parameters and Quality of Life in Women with Breast Cancer in Terms of Rehabilitation

<b>Objectives</b>: The aim of the study was to assess the impact of oncological treatment including surgery and radiotherapy on the respiratory function and quality of life of women treated for breast cancer, considering the effects of physiotherapy and additional inspiratory muscle training. <b>Methods</b>: A quantitative, repeated-measures study included 26 women (aged 30-69) with breast cancer who had undergone breast-conserving surgery and radiotherapy, randomly assigned to an IMT group or a sham IMT group. The following tests were performed on each patient: respiratory function, respiratory muscle strength, the WHOQOL-Bref questionnaire. The tests were performed five times as follows: before surgery, after surgery (4-6 days), before the start of radiotherapy (4-5 weeks after surgery), after the end of radiotherapy, and follow-up 4 weeks after the end of radiotherapy. Group I-IMT: patients underwent physiotherapy according to hospital rehabilitation standards and inspiratory muscle strength training at 15-60% PI_max. Group II-sham-IMT: patients underwent physiotherapy according to hospital rehabilitation standards and inspiratory muscle strength training at 15% PI_max. <b>Results</b>: After the surgery, a reduction in all parameters was observed, which improved gradually and depending on the group after physiotherapy and inspiratory muscle training. The PI_max value decreased significantly after the procedure in both groups (<i>p</i> = 0.00), but its significant increase after 4 weeks and radiotherapy (<i>p</i> = 0.00) was noted only in the I-IMT group. The quality of life assessed by women (WHO1) was significantly higher (<i>p</i> = 0.009) only in the group using IMT training with a load of 60% PI_max. <b>Conclusions</b>: Radical breast cancer treatment, including surgery and radiotherapy, significantly impairs respiratory function and quality of life in women, with the greatest deterioration observed after surgery. The use of prehabilitation and postoperative physiotherapy reduces the adverse effects of radical treatment, while additional inspiratory muscle training supports the improvement of respiratory function and the subjective assessment of quality of life in patients.