Study of the Utility of the BOMET-QOL Questionnaire Patients With Breast Cancer and Bone Metastasis

Impact on the HRQoL of patients with BC and BM will be measured by the BOMET-QoL questionnaire in the context of normal clinical practice. The questionnaire will be administered to patients in each study visit from baseline visit to the final visit at 24 months. The score of the questionnaire will be measured as: Score: 0 - Always, 1 - Nearly always, 2 - Sometimes, 3 - Rarely, 4 - Never, were never is the best option and always means patient has a bad health condition.

Its cross-sectional validity will be evaluated by analysing the relationship between the BOMET-QoL scores and different clinical variables (presence of Skeleton-Related Event (SREs), symptoms and Eastern Cooperative Oncology Group (ECOG) index). The relationship between the pain VAS score and the question about state of health perceived by patient with HRQoL according to BOMET-QoL will be analysed.

BOMET-QoL will be considered rapidly completed if patients complete questionnaire in less than 10 minutes.

Sensitivity to change can be evaluated by calculating the effect size or the Minimum Clinically Important Difference, as statistics based on effect size provide direct information about the magnitude of the change, expressed as a variation, also used to calculate the Minimum Clinically Important Difference.

The impact of skeletal-related events (SREs) on HRQoL (BOMET-QoL scores) will be measured by comparing patients who presented SREs with patients with without SREs.

ECOG: This scale consists of 5 levels (0 = No restrictions to carry out the activities normal, 1 = Restrictions to perform vigorous physical activities. It has the capacity to perform ambulation and light work, 2 = Ability to ambulate and perform personal care but not able to work. Capacity for standing and walking for> 50% of waking hours, 3 = Able to perform care limited personal; Incarcerated or restrained to be in a chair for> 50% of the hours of vigil, 4 = complete disability; he can not perform any personal care; it remains in bed or in a chair all the time, 5 = Death). In it the observer assesses the state of symptoms and the level of functioning in relation to ambulatory status and need for care. Patients with an Eastern Cooperative Oncology Group (ECOG) functional scale between 0-1 will obtain a higher score (better HRQoL) in the BOMET-QoL questionnaire.

At the baseline visit, patients who obtain higher scores on the Analogue Visual Pain Scale will obtain a lower score (worse HRQOL) in the BOMET-QoL questionnaire. Correlation between the BOMET-QoL scores and the pain VAS scores regarding whether it improves, stays the same or gets worse between the different study visits. VAS: 0 no pain - 10 unbearable pain