Oral versus intravenous ibandronic acid: a comparison of treatment options for metastatic bone disease

Review of Bone Modifying Agents in Metastatic Breast Cancer

Bone is the most common site for distant metastases in breast cancer and can cause significant morbidity and mortality. Bone modifying agents (BMAs) that include bisphosphonates (BPAs) and denosumab help in decreasing and delaying skeletal-related events (SREs) associated with metastatic breast cancer. BPAs approved for use by the Food and Drug Administration (FDA) in bone metastases (BM) in the United States are pamidronate and zolendronic acid, while clodronate and ibandronate are licensed for use in other countries. Current American Society of Clinical Oncology (ASCO) guidelines recommend denosumab 120 mg subcutaneously every four weeks, or zolendronic acid 4 mg every four weeks or every 12 weeks, or intravenous pamidronate 90 mg every four weeks. Current guidelines do not recommend one BMA over another, however, zolendronic acid and denosumab were the most commonly used BMAs in population-based studies. Side effects of BMAs include acute phase reactions, hypocalcemia, nephrotoxicity, osteonecrosis of jaw, etc. While other side effects are common with both BPAs and denosumab, the latter has less nephrotoxic potential and is preferred for use in patients with renal failure. Current ASCO guidelines recommend continuing BMAs indefinitely, however, in clinical practice, this decision needs to be individualized, especially since there is no data on the impact of long-term use of BMAs. Further studies would need to be developed to develop an algorithm of SRE risk assessment and to determine which patients would benefit from BMAs.

Bone-targeted therapy use in patients with bone metastases from lung cancer: A systematic review of randomized controlled trials

BACKGROUND

Patients with advanced lung cancer commonly have bone metastases. Compared with other malignancies, the use of bone-targeted agents (e.g. bisphosphonates and denosumab) is less common in lung cancer patients. This may be due to the perception that bone-targeted agents are less effective in this population.

OBJECTIVE

To perform a systematic review to evaluate data from randomized trials of bone-targeted agents in lung cancer patients with bone metastases.

METHODS

A systematic search of Medline, Embase and the Cochrane Register of Controlled Trials through May 2015 was performed. Randomized trials of bone-targeted therapies in lung cancer patients with bone metastases were sought. Outcomes studied included skeletal related events (SREs), pain, quality of life, progression-free survival and overall survival. Random effects meta-analyses were planned if studies were judged homogeneous.

RESULTS

Of 632 abstracts, 17 publications describing 13 studies were included. Sample sizes ranged between 50 and 1776. Of 3379 patients, 1903 had lung cancer, with subgroup data available for 8 of 13 studies. Patient demographics were comparable, but enrollment criteria and endpoints were heterogeneous across studies, precluding meta-analysis. Study-specific results suggested that bone-modifying agents reduce the incidence of SREs and bone pain in lung cancer patients. Three studies suggested a survival benefit.

CONCLUSION

Data from included trials suggests benefit of bone-targeted agents in lung cancer for the prevention of SREs and bone pain. There is a trend toward improvement in overall survival and progression-free survival, although further research is needed. Impact on quality of life and key subgroups for benefit both require future research.

Incidence and consequences of bone metastases in lung cancer patients

Background

Bone metastases (BM) are common in NSCLC patients. Despite some potential positive effects of bone-targeted therapies, their use in NSCLC is infrequent, which may relate to the overall poor prognosis of advanced lung cancer. We reviewed the literature to evaluate the incidence, consequences and use of bone-targeting agents in lung cancer patients with BM in both the trial and non-trial clinical setting.

Methods

Published prospective and retrospective papers investigating lung cancer and BM, in trial and non-trial settings, were identified and are discussed in this review.

Results

BM are common in patients with advanced lung cancer and often present symptomatically with pain and skeletal related events (SREs). Patients with high bone turnover marker levels, multiple BM, and history of pathological fractures have shorter overall survival. In randomized studies bone-targeted therapies reduced the risk of SREs and prolonged the time to first SRE. The use of bone-targeted agents may also be associated with a survival benefit.

Conclusion

BM are a common problem in advanced lung cancer. While the benefits of bone-targeted therapies have been demonstrated, their use is limited in non-trial populations. If better predictive markers of individual risk were available this might increase the appropriate use of bone-targeted agents.

External validity of the Tokuhashi score in patients with vertebral metastasis

PURPOSE

To calculate the accuracy of the Tokuhashi score (TS) in recent patients with vertebral metastasis (VM), candidates or not to surgical treatment, and thus to assess the external validity of TS.

METHODS

Retrospective analysis of prospectively collected data from 90 patients (55 men, 35 women) with VM between 2004 and 2006. For each patient, data on the primary tumor (PT), date of diagnosis, TS at the time of VM diagnosis and date of death were retrieved from the electronic medical records and civil registry. True survival time and TS survival time were estimated to calculate the accuracy rate of the TS. A Kaplan-Meier analysis was used to study the survival function by prognostic groups. A correlation study between survival time and other variables was performed.

RESULTS

PT distribution was as follows: breast (22.2 %), lung (20 %), prostate (17.8 %), rectum (10 %), unknown (11 %), and others (18 %). Average overall survival after the VM diagnosis was 11.8 months (SD, 11 m): breast, 20 months (SD, 20 m); lung, 5.8 months (SD, 5.9 m); prostate, 14.5 months (SD, 13.4 m); rectum, 9.4 months (SD, 9.3); and unknown tumors, 2.7 months (SD, 5 m). Survival time was accurately predicted with the TS in 63 % of patients with a short life expectancy (survival, <6 months; TS, 0-8), 16 % of patients in the intermediate group (survival, 6-12 months; TS, 9-11), and 77 % of patients with a good prognosis (survival >12 months; TS, 12-15). By specific PT, the accuracy rate of the TS was low for breast cancer metastasis (35 %). The Kaplan-Meier curves show a significant separation among the prognostic groups (p < 0.05), but the log-rank test showed a statistically significant difference in survival only between short expectancy group and good prognostic group. Age at PT diagnosis and at VM diagnosis negatively correlated with survival (r = 0.22; p = 0.032 and r = 0.3, p = 0.04).

CONCLUSIONS

The TS was not highly accurate for predicting survival in patients with VM, treated or not surgically, and it was particularly imprecise in patients with an intermediate score (9-11 points) and those with breast cancer, so it is possible that the TS currently has a poor external validity.

Denosumab for treatment of bone metastases secondary to solid tumours: systematic review and network meta-analysis

AIM

To evaluate the evidence for denosumab for the treatment of bone metastases secondary to solid tumours and, using a network meta-analysis, indirectly compare denosumab with bisphosphonates and best supportive care.

DATA SOURCES

MEDLINE (1948 to April 2011), EMBASE (1980 to March 2011), Cochrane Library (all sections) (issue 1, 2011) and Web of Science with Conference Proceedings (1970 to May 2011) and additional meeting abstracts (2010 and 2011) were searched. STUDY ELIGIBILITY, PARTICIPANTS AND INTERVENTIONS: Only randomised controlled trials assessing denosumab, bisphosphonates or best supportive care in patients with bone metastases from any solid tumour were included.

SYNTHESIS

Direct evidence comparing denosumab and zoledronic acid was assessed for breast cancer, prostate cancer and other solid tumours. Denosumab was compared with pamidronate and best supportive care through a network meta-analysis for each tumour type. The primary outcomes were time to first skeletal related event (SRE) and time to first and subsequent SRE. Secondary outcomes were skeletal morbidity rate, pain, quality of life (QoL) and overall survival.

RESULTS

Denosumab was found to be more effective in delaying the time to first SRE and reducing the risk of first and subsequent SRE compared to zoledronic acid, placebo and pamidronate. In breast and prostate cancer, denosumab was effective in reducing skeletal morbidity rate compared with placebo. The lack of published data on pain and QoL meant that firm conclusions could not be made. Denosumab did not appear to have an affect on overall survival.

LIMITATIONS

Network meta-analyses are subject to uncertainties and potential biases.

CONCLUSIONS

Denosumab is effective in preventing SRE, but the effect on pain and QoL is unclear.

Patient-reported outcome instruments used to assess pain and functioning in studies of bisphosphonate treatment for bone metastases

Purpose

When treating metastatic bone disease, relief of bone pain is often a key outcome. Because pain cannot be quantified with objective clinical measures, patient-reported outcome (PRO) measures are required to assess patients' subjective experience. The goal of the current review was to examine measures used to assess pain, as well as the impact of pain on functional status and health-related quality of life (HRQL), in trials of bisphosphonates for the treatment of bone metastases.

Methods

A literature search focused on articles published from January 1999 to April 2009.

Results

A total of 49 articles were located that used PROs to assess pain-related outcomes of bisphosphonate treatment for bone metastases. The Brief Pain Inventory was the most commonly used multi-item instrument. However, the most common approach for assessing pain was to administer a single-item scale such as a visual analog scale, numerical rating scale, or verbal rating scale. Of the 49 studies, 19 included a PRO assessing functional status or HRQL.

Conclusions

Although pain is an important outcome of trials examining treatment for bone metastases, the current review suggests that there is little consistency in PRO measurement across studies. Furthermore, presentation of measures often lacked clear description, information on measurement properties, citations, clarity regarding method of administration, and consistent instrument names. Recommendations are provided for instrument validation within the target population, assessment of content validity, use of PRO instruments recently developed for patients with bone metastases, clear description of instruments, and implementation of measures consistent with recommendations from instrument developers.