Loading dose ibandronate versus standard oral ibandronate in patients with bone metastases from breast cancer

Development and application of a urine drug concentration method for the evaluation of oral absorption of ibandronate in clinical patients

Aim: A urine drug concentration method was developed for the evaluation of oral ibandronte absorption based on the fact that ibandronate is excreted unchanged by the kidneys. Methodology: Ibandronate was isolated from the urine matrix by coprecipitated with 2.5 M CaCl₂ and 1 M K₂HPO₄ in basic conditions. After a liquid-liquid extraction, the analytes were derivatized with trimethylsilydiazomethane prior to detection. Results: The calibration curves exhibited excellent linearity (r > 0.99) between 1 and 250 ng/ml in human urine. Ibandronate was recovered >86.5% with the inter- and intraday relative standard deviations less than 15%. Conclusion: The method is selective, accurate, practical and was successfully applied to study the influence of vitamin D₃ on the absorption of ibandronate.

The incidence and relative risk of adverse events in patients treated with bisphosphonate therapy for breast cancer: a systematic review and meta-analysis

Background:

Adjuvant bisphosphonates reduce the rate of breast cancer recurrence in the bone and improve breast cancer survival. However, the risk of adverse events associated with bisphosphonate therapy for breast cancer remains poorly defined.

Methods:

A literature search was conducted using the PubMed, EMBASE, Cochrane and Web of Science libraries. Risk ratio (RR) was calculated to evaluate the adverse events of the meta-analytic results. Osteonecrosis of the jaw (ONJ) incidence was calculated using the random effect model (D+L pooled) for meta-analysis.

Results:

A total of 47 studies comprising 20,607 patients were included; 23 randomized controlled studies (RCTs) provided data of adverse events for bisphosphonate therapy versus without bisphosphonates. Bisphosphonates were significantly associated with influenza-like illness (RR = 4.52), fatigue (RR = 1.08), fever (RR = 1.82), dyspepsia (RR = 1.25), anorexia (RR = 1.29), and urinary tract infection (RR = 1.32). No differences were observed in other adverse events. We combined the incidence of ONJ in 24 retrospective studies to analyze the incidence of ONJ using bisphosphonates. The pooled probability of ONJ toxicity in the bisphosphonates group was 2%.

Conclusions:

Bisphosphonates were significantly associated with influenza-like illness, fatigue, fever, dyspepsia, anorexia, and urinary tract infection. Furthermore, bisphosphonates increase the risk of ONJ toxicity.

Bone turnover markers and novel biomarkers in lung cancer bone metastases

CONTEXT

Lung cancer still remains the leading cause of cancer-related mortality worldwide. Bone is one of preferred metastatic sites for lung cancer cells. So far, both accurate diagnosis and effective treatment of lung cancer bone metastases are difficult.

OBJECTIVE

This review aimed to evaluate roles of bone turnover markers (BTMs), microRNAs (miRNAs), dickkopf1 (DKK1) and insulin like growth factor binding protein 3 (IGFBP-3) in lung cancer bone metastases.

METHODS

We searched articles about these four biomarkers in lung cancer bone metastases mainly in PubMed.

RESULT

The levels of bone specific alkaline phosphatase (BALP), cross-linked carboxy-terminal telopeptide of type-I collagen (ICTP) and N-terminal telopeptides of type-I collagen (NTX) were reported to be significantly increased in lung cancer patients with bone metastases. ALP, NTX and bone sialoprotein were thought to be associated with prognosis of lung cancer patients with bone metastases. MiRNA-335, miRNA-33a, miRNA-21, DKK1 and IGFBP-3 were revealed to be novel biomarkers in lung cancer bone metastases.

DISCUSSION AND CONCLUSION

Current researches have revealed that BTMs, miRNAs, DKK1 and IGFBP-3 may be useful in diagnosis, prognosis evaluation or treatment of lung cancer bone metastases. More studies about these biomarkers in lung cancer bone metastases are needed.

Bone metabolism markers: Indicators of loading dose intravenous ibandronate treatment for bone metastases from breast cancer

To investigate the changes in bone metabolism markers after second-line treatment with loading dose intravenous (i.v.) ibandronate in patients with bone metastases (BM) from breast cancer, 80 patients were enrolled in this study during January 2010 to April 2014. All the patients were treated with a second-line loading dose ibandronate for advanced breast cancer with BM and moderate-to-severe bone pain. Ibandronate (6 mg) was intravenously administered on three consecutive days followed by maintenance treatment every 3-4 weeks. Clinical data, including pain score, Karnofsky performance status (KPS) score, and changes in bone metabolism markers, were analyzed. Sixty-two patients were included in the final analysis. Compared with their pre-treatment scores, patients exhibited significantly increased KPS scores (P < .01) and a reduced dose of analgesic medication (oxycodone) (P < .01) after 3 and 6 weeks' post-treatment. The levels of serum bone alkaline phosphatase (BAP), tartrate-resistant acid phosphatase (TRACP-5b), and cross-linked carboxy-terminal telopeptide of type I collagen (ICTP) were significantly reduced after 3 and 6 weeks' post-treatment (P < .001). Aside from a few adverse events, no liver or renal toxicity was observed. Bone metabolism markers decreased by varying degrees after treatment with a loading dose of ibandronate in patients with BM from breast cancer. It might be convenient using bone metabolism markers to potentially evaluate the efficacy of bisphosphonates treatment for bone metastasis.