The clinical response on bone metastasis from breast and lung cancer during treatment with zoledronic acid is inversely correlated to skeletal related events (SRE).

Current management of bone metastases involves a multimodal approach. Aminobisphosphonates (BPs) are a valid weapon in the treatment of skeletal localization of tumour disease. Patients with bone metastases from breast and lung cancer were enrolled in order to evaluate the impact of the addition of bisphosphonates therapy to standard treatments in terms of (i) pain control, (ii) quality of life (QoL) and (iii) toxicity and to evaluate (iv) any relations between clinical activity and the occurrence of SREs. A total of 60 patients were included in the study. Median age was 76 years (range 40-83). The majority of patients were treated with chemotherapy or hormonal therapy. All patients received zoledronic acid (ZOL) (4 mg) every 3-4 weeks for at least 3 cycles. No significant improvement in Performance Status of patients after 12 cycles of ZOL (p = 0.1672) was recorded. A statistically significant early and long-lasting amelioration of both pain, narcotic scores and QoL was found. Twenty-one patients (48%) experienced at least one SRE during the study. The most common SRE was radiation to bone (30% of patients). An inverse correlation between bone tumour response and SREs was also found (p = 0.019). ZOL addition induces a clinical benefit and improves QoL of patients with bone metastases. Moreover, the occurrence of bone clinical response is related to a reduced risk of SREs.