Incidence of skeletal-related events over time from solid tumour bone metastases reported in randomised trials using bone-modifying agents

Review on effects and mechanisms of plant-derived natural products against breast cancer bone metastasis

Bone metastasis is the prevalent form of metastasis in breast cancer, resulting in severe pain, pathological fractures, nerve compression, hypercalcemia, and other complications that significantly impair patients' quality of life. The infiltration and colonization of breast cancer (BC) cells in bone tissue disrupt the delicate balance between osteoblasts and osteoclasts within the bone microenvironment, initiating a vicious cycle of bone metastasis. Once bone metastasis occurs, conventional medical therapy with bone-modifying agents is commonly used to alleviate bone-related complications and improve patients' quality of life. However, the utilization of bone-modifying agents may cause severe drug-related adverse effects. Plant-derived natural products such as terpenoids, alkaloids, coumarins, and phenols have anti-tumor, anti-inflammatory, and anti-angiogenic pharmacological properties with minimal side effects. Certain natural products that exhibit both anti-breast cancer and anti-bone metastasis effects are potential therapeutic agents for breast cancer bone metastasis (BCBM). This article reviewed the effects of plant-derived natural products against BCBM and their mechanisms to provide a reference for the research and development of drugs related to BCBM.

Factors associated with skeletal-related events in patients with bone metastatic melanoma: A retrospective study of 481 patients

OBJECTIVES

Metastatic bone disease is estimated to develop in up to 17% of patients with melanoma, compromising skeleton integrity resulting in skeletal-related events (SREs), which impair quality of life and reduce survival. The objective of the study was to investigate (1) the proportion of melanoma patients developing SREs following diagnosis of bone metastasis and (2) the predictors for SREs in this patient cohort.

METHODS

Four hundred and eighty-one patients with bone metastatic melanoma from two tertiary centers in the United States from 2008 to 2018 were included. The primary outcome was 90-day and 1-year occurrence of a SRE, including pathological fractures of bones, cord compression, hypercalcemia, radiotherapy, and surgery. Fine-Gray regression analysis was performed for overall SREs and pathological fracture, with death as a competing risk.

RESULTS

By 1-year, 52% (258/481) of patients experienced SREs, and 28% (137/481) had a pathological fracture. At 90-day, lytic lesions, bone pain, elevated calcium and absolute lymphocyte, and decreased albumin and hemoglobin were associated with higher SRE risk. The same factors, except for decreased hemoglobin, were shown to predict development of SREs at 1-year.

CONCLUSION

The high incidence of SREs and pathological fractures warrants vigilance using the identified factors in this study and preventative measures during clinical oncological care.

Treatment Patterns of Bone-targeting Agents Among Solid Tumor Patients With Bone Metastases: An Analysis of Electronic Health Record Data in the United States From 2014 to 2018

OBJECTIVES

This study evaluated real-world treatment patterns of approved bone-targeting agents (BTAs) with various mechanisms of action-pamidronate, zoledronic acid, and denosumab-for the prevention of skeletal-related events in patients with bone metastases (BM) from solid tumors.

METHODS

Adult patients with BM secondary to solid tumors between January 1, 2014, and December 31, 2018, were identified from the Flatiron Health Oncology Services Comprehensive Electronic Records database and categorized by BTA use and therapy type. Time from diagnosis to initiation, persistence (mean time on treatment), and compliance (≥12 administrations/year) with BTA with up to 4 years of follow-up were examined.

RESULTS

This study included 27,268 patients with BM (breast cancer, 32.7%; lung cancer, 16.5%; prostate cancer, 17.2%; and other solid tumors, 33.6%); of these, 41.4% initiated denosumab after BM diagnosis; 21.3%, zoledronic acid; 0.6%, pamidronate; and 36.7% had no treatment record. Mean (SD) time to initiation for denosumab or zoledronic acid was 68.6 (157.0) days (denosumab, 70.3 (160.4) days; zoledronic acid, 65.2 [150.2] days). Mean persistence and compliance (first year of treatment) were significantly higher for denosumab than for zoledronic acid (22.0 vs. 14.9 mo [ P <0.0001] and 42.3% vs. 34.8% [ P <0.0001], respectively). Treatment compliance was the highest in patients with breast cancer (denosumab, 48.2%; zoledronic acid, 39.1%).

CONCLUSION

Real-world BTA treatment patterns in the United States suggest that over one-third of patients with BM secondary to solid tumors remain untreated and less than 50% of the patients received ≥12 administrations/year of BTA therapy.

Randomized phase II study of zoledronate dosing every four versus eight weeks in patients with bone metastasis from lung cancer (Hanshin Cancer Group0312)

BACKGROUND

Zoledronic acid (ZA) reduces the incidence of skeletal-related events (SREs) in patients with bone metastases from solid tumors. However, the optimal dosing interval of ZA for patients with lung cancer is uncertain.

METHODS

We conducted a randomized, open-label, feasibility phase 2 trial at eight Japanese hospitals. Patients with bone metastases from lung cancer were randomly assigned to receive either 4 mg of ZA every four weeks (4wk-ZA) or every eight weeks (8wk-ZA). The primary endpoint was the time to the first SRE and the rate and types of SREs after one year. SREs were defined as pathologic bone fracture, bone radiation therapy or surgery, and spinal cord compression. Secondary endpoints were the SRE incidence at six months, pain assessment, changes in analgesic consumption, serum N-telopeptide, toxicity, and overall survival.

RESULTS

Between November 2012 and October 2018, 109 patients were randomly assigned to the 4wk-ZA group (54 patients) and the 8wk-ZA group (55 patients). The number of patients who received chemotherapy or molecular-targeted agents was 30 and 23 and 18 and 16 in the 4wk-ZA and 8wk-ZA groups, respectively. The median time to the first SRE could not be calculated because of a low SRE. The time to the first SRE of all patients did not differ between the groups (P = 0.715, HR = 1.18, 95% CI = 0.48, 2.9). The SRE rate of all patients after 12 months was 17.6% (95% CI = 8.4, 30.9%) in the 4wk-ZA and 23.3% (95% CI = 11.8, 38.6%) in the 8wk-ZA group, without significant differences between the groups. There was no difference in any secondary endpoint between groups, and these endpoints did not differ among treatment modalities.

CONCLUSIONS

An eight-week ZA interval does not increase the SRE risk for patients with bone metastasis from lung cancer and could be considered clinically.

Breast Cancer Epidemiology and Contemporary Breast Cancer Care: A Review of the Literature and Clinical Applications

Substantial progress has been made in contemporary breast cancer care, resulting in a consistently declining breast cancer mortality rate and an improvement in quality of life. Advancements include deescalation of therapy in low-risk populations and refining systemic therapy options. Research into molecular biomarkers continues to evolve and holds the promise of achieving the goal of precision medicine, while guidelines for supportive care and survivorship have been created to address the needs of an ever-increasing number of breast cancer survivors. A collaborative, multidisciplinary team approach is essential for patients and survivors to achieve optimal outcomes and enjoy productive high-quality lives. Gynecologists, in particular, play a key role in screening and survivorship care.

Posterior Percutaneous Pedicle Screws Fixation Versus Open Surgical Instrumented Fusion for Thoraco-Lumbar Spinal Metastases Palliative Management: A Systematic Review and Meta-analysis

Background

Surgical palliative treatment of spinal metastases (SM) could influence the quality of life (QoL) in cancer patients, since the spine represents the most common site of secondary bony localization. Traditional open posterior instrumented fusion (OPIF) and Percutaneous pedicle screw fixation (PPSF) became the main surgical treatment alternatives for SM, but in Literature there is no evidence that describes the absolute superiority of one treatment over the other.

Materials and Methods

This is a systematic review and meta-analysis of comparative studies on PPSF versus OPIF in patients with SM, conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The outcomes of interest were: complications, blood loss, infections, mortality, pain and also the Quality of Life (QoL).

Results

There were a total of 8 studies with 448 patients included in the meta-analyses. Postoperative complications were more frequent in OPIF (odds ratio of 0.48. 95% CI, 0.27 to 0.83; p= 0.01), PPFS was associated with blood loss (odds ratio -585.70. 95% IC, -848.28 to -323.13.69; p< 0.0001) and a mean hospital stay (odds ratio -3.77. 95% IC, -5.92 to -1.61; p= 0.0006) decrease. The rate of infections was minor in PPFS (odds ratio of 0.31. 95% CI, 0.12 to 0.81; p= 0.02) whereas the occurrence of reinterventions (0.76. 95% CI, 0.25 to 2.27; p= 0.62) and the mortality rate was similar in both groups (odds ratio of 0.79. 95% CI, 0.40 to 1.58; p= 0.51). Finally, we also evaluated pre and post-operative VAS and the meta-analysis suggested that both techniques have a similar effect on pain.

Discussion and Conclusion

The PPSF treatment is related with less complications, a lower rate of infections, a reduction in intraoperative blood loss and a shorter hospital stay compared to the OPIF treatment. However, further randomized clinical trials could confirm the results of this meta-analysis and provide a superior quality of scientific evidence.

Association of Osteonecrosis of the Jaw With Zoledronic Acid Treatment for Bone Metastases in Patients With Cancer

Importance

Osteonecrosis of the jaw (ONJ) affects patients with cancer and metastatic bone disease (MBD) treated with bone-modifying agents (BMAs), yet the true incidence is unknown.

Objective

To define the cumulative incidence of ONJ at 3 years in patients receiving zoledronic acid for MBD from any malignant neoplasm.

Design, Setting, and Participants

This multicenter, prospective observational cohort study (SWOG Cancer Research Network S0702) included patients with MBD with either limited or no prior exposure to BMAs and a clinical care plan that included use of zoledronic acid within 30 days of registration. Medical, dental, and patient-reported outcome forms were submitted at baseline and every 6 months. Follow-up was 3 years. Osteonecrosis of the jaw was defined using established criteria. Data were collected from January 30, 2009, to December 13, 2013, and analyzed from August 24, 2018, to August 6, 2020.

Interventions/Exposures

Cancer treatments, BMAs, and dental care were administered as clinically indicated.

Main Outcomes and Measures

Cumulative incidence of confirmed ONJ, defined as an area of exposed bone in the maxillofacial region present for more than 8 weeks with no concurrent radiotherapy to the craniofacial region. Risk factors for ONJ were also examined.

Results

The SWOG S0702 trial enrolled 3491 evaluable patients (1806 women [51.7%]; median age, 63.1 [range, 2.24-93.9] years), of whom 1120 had breast cancer; 580, myeloma; 702, prostate cancer; 666, lung cancer; and 423, other neoplasm. A baseline dental examination was performed in 2263 patients (64.8%). Overall, 90 patients developed confirmed ONJ, with cumulative incidence of 0.8% (95% CI, 0.5%-1.1%) at year 1, 2.0% (95% CI, 1.5%-2.5%) at year 2, and 2.8% (95% CI, 2.3%-3.5%) at year 3; 3-year cumulative incidence was highest in patients with myeloma (4.3%; 95% CI, 2.8%-6.4%). Patients with planned zoledronic acid dosing intervals of less than 5 weeks were more likely to experience ONJ than patients with planned dosing intervals of 5 weeks or more (hazard ratio [HR], 4.65; 95% CI, 1.46-14.81; P = .009). A higher rate of ONJ was associated with fewer total number of teeth (HR, 0.51; 95% CI, 0.31-0.83; P = .006), the presence of dentures (HR, 1.83; 95% CI, 1.10-3.03; P = .02), and current smoking (HR, 2.12; 95% CI, 1.12-4.02; P = .02).

Conclusions and Relevance

As the findings show, the cumulative incidence of ONJ after 3 years was 2.8% in patients receiving zoledronic acid for MBD. Cancer type, oral health, and frequency of dosing were associated with the risk of ONJ. These data provide information to guide stratification of risk for developing ONJ in patients with MBD receiving zoledronic acid.

Spine and Non-spine Bone Metastases - Current Controversies and Future Direction

Bone is a common site of metastases in advanced cancers. The main symptom is pain, which increases morbidity and reduces quality of life. The treatment of bone metastases needs a multidisciplinary approach, with the main aim of relieving pain and improving quality of life. Apart from systemic anticancer therapy (hormonal therapy, chemotherapy or immunotherapy), there are several therapeutic options available to achieve palliation, including analgesics, surgery, local radiotherapy, bone-seeking radioisotopes and bone-modifying agents. Long-term use of non-steroidal analgesics and opiates is associated with significant side-effects, and tachyphylaxis. Radiotherapy is effective mainly in localised disease sites. Bone-targeting radionuclides are useful in patients with multiple metastatic lesions. Bone-modifying agents are beneficial in reducing skeletal-related events. This overview focuses on the role of surgery, including minimally invasive treatments, conventional radiotherapy in spinal and non-spinal bone metastases, bone-targeting radionuclides and bone-modifying agents in achieving palliation. We present the clinical data and their associated toxicity. Recent advances are also discussed.

Prognostic Value of RANKL/OPG Serum Levels and Disseminated Tumor Cells in Nonmetastatic Breast Cancer

PURPOSE

We assessed serum concentrations of the receptor activator of NFκB ligand (RANKL) and its decoy receptor, osteoprotegerin (OPG), two proteins implicated in the development and progression of breast cancer, in 509 patients with primary, nonmetastatic breast cancer. Then the results were evaluated with regards to the occurrence of bone metastases, the presence of disseminated tumor cells (DTC) in the bone marrow, survival, and risk of developing metastatic disease.

EXPERIMENTAL DESIGN

Before surgery, two bone marrow aspirates were analyzed for DTC using density centrifugation followed by immunocytochemistry (pan-cytokeratin antibody A45-B/B3). RANKL and OPG levels in the serum were measured by ELISA.

RESULTS

RANKL levels were significantly lower in women >60 years (P < 0.0001) and RANKL/OPG ratios higher in lymph node-positive patients (P < 0.05). High OPG serum levels were associated with a higher risk of death from breast cancer [HR 1.94; 95% confidence interval (CI) 1.23-3.07; P = 0.005] and OPG was an independent prognostic marker for breast cancer-specific survival (BCSS; multivariate analyses, P = 0.035). RANKL levels were 33% higher (P < 0.0001) in DTC^pos patients (41%), whereas high levels were associated with a significantly better BCSS in DTC^neg patients as compared with low levels (HR 0.524; 95% CI 0.30-0.95; P = 0.04). RANKL serum levels were significantly increased in patients who developed bone metastases (P = 0.01) and patients within the highest quartile of RANKL had a significantly increased risk of developing bone metastases compared with those in the lowest (HR 4.62; 95% CI 1.49-14.34; P = 0.03).

CONCLUSIONS

These findings warrant further investigation as they provide a rationale for novel diagnostic or therapeutic approaches.

Outcomes and Prognosis of Neurological Decompression and Stabilization for Spinal Metastasis: Is Assessment with the Spinal Instability Neoplastic Score Useful for Predicting Surgical Results?

Study Design

Retrospective study.

Purpose

To evaluate the efficacy of the Spinal Instability Neoplastic Score (SINS) in predicting surgical outcomes and survival. Patients were categorized into two groups according to the SINS, and their surgical outcomes and survival following decompression and stabilization were assessed.

Overview of Literature

Palliative surgery in patients with a life expectancy ≥3 months may effectively improve their overall condition in the long term. Currently, the effectiveness of the SINS for predicting surgical results and survival remains controversial.

Methods

This study included 44 patients who underwent decompression and stabilization for spinal metastases at Yokosuka Kyosai Hospital between 2008 and 2017. The patients were divided into two groups: stable (SINS ≤12) and unstable (SINS ≥13). Changes in the Frankel score and Eastern Cooperative Oncology Group Performance Status (ECOG-PS) were compared between the two groups, and patient survival was evaluated according to the SINS, Tokuhashi score, and Katagiri score.

Results

The stable group (SINS range, 7–12) included 24 patients while the unstable group (SINS range, 13–16) included 20 patients. The Frankel score significantly improved from 2.8 to 3.6 in the stable group (p <0.001) and from 2.7 to 3.9 in the unstable group (p <0.001). The ECOG-PS significantly improved from 3.2 to 2.1 in the stable group (p <0.001) and from 3.0 to 1.8 in the unstable group (p <0.001). There was a statistically significant difference in median survival between the two groups.

Conclusions

All patients treated with palliative surgery showed favorable outcomes, as indicated by improved the Frankel score and ECOG-PS following surgery. However, median survival was significantly better in the stable group. The results of this study indicate that the SINS is appropriate for surgical decision making and may be used to predict survival.

Patient survival following joint replacement due to metastatic bone disease - comparison of overall patient and prostheses survival between cohorts treated in two different time-periods

BACKGROUND

Improvements in medical treatment for cancer have increased survival of cancer patients. We hypothesize that improvement in cancer treatment is reflected in increased survival after surgical intervention for metastatic bone disease (MBD) and that subsequent revision surgery does not pose a risk for survival.

METHODS

We identified a retrospective consecutive cohort who received bone resection and reconstruction (BRR) with implants (including total joint replacements (with or without wide resection) or bone reconstruction with an intercalary spacer or revisions procedures for failed implants with BBR technique) due to MBD from 2003 to 2008 (early cohort) and 2009 to 2013 (late cohort) at a tertiary referral center. We registered epidemiological data, type of implant (primary or a revision implant), patient survival (Kaplan-Meier), implant survival (competing risk analysis) and complications to surgery.

RESULTS

Three hundred and eleven procedures were performed in 291 patients (289 primary BRR (270 patients, early cohort n = 130 late cohort n = 140) and 22 revision BRR (21 patients)). Overall survival was 44% (95% confidence intervals (95% CI): 39-50) and 32% (95% CI: 27-38) after 1 and 2 years. No difference in survival between the early and late cohort was found (p = .458), or between primary and revision BRR (p = .465). Time from diagnosis of cancer to surgery was shorter in the early cohort (p < .001). The cumulative incidence of failure of implant was 2% (95% CI: 0-3%) at 1 year and 3% (95% CI: 1-6%) at 2 years. One year cumulative implant failure for revision implants was 5% (95% CI: 0-13%) at 1 and 2 years. The risk of failure was not statistical significant between primary and revision implant (p = .293) in competing risk analysis.

DISCUSSION

We were not able to identify an increased survival after surgery for MBD over time, however, we found an increased interval from diagnosis to surgery for MBD. This study suggests that revision surgery for MBD does not pose a risk for survival.

FDG PET/CT Assesses the Risk of Femoral Pathological Fractures in Patients With Metastatic Breast Cancer

PURPOSE

Assessment of pathological fracture risk is critical to optimize the use of prophylactic orthopedic fixation to prevent pathological fractures. Better prediction of pathological fracture risk is needed. We evaluated if quantitative measures of FDG avidity can assess femoral pathological fracture risk in patients with metastatic breast cancer (MBC).

PATIENTS AND METHODS

A Health Insurance Portability and Accountability Act-compliant retrospective case-control study was performed under institutional review board waiver. Patients with MBC who received an FDG PET/CT from January 2008 to December 2014 and had pathological fracture of the proximal femur within 3 months of PET/CT were selected as cases. Patients with MBC who had an FDG PET/CT in 2013 were sequentially screened in reverse chronological order to identify patients with proximal femoral metastases on PET/CT but no subsequent pathological fracture to serve as a control group. The prespecified goal was to have twice the number of controls as cases. Target lesions in the proximal femur, from femoral head to 5 cm below the lesser trochanter, were analyzed on FDG PET/CT for SUVmax, SUVmean, metabolic tumor volume, and total lesion glycolysis. Wilcoxon rank sum test was used to compare continuous variables in cases and controls. A nonparametric receiver operating characteristic analysis was performed to assess the ability of quantitative FDG measurements to differentiate between cases and controls.

RESULTS

In 27 cases with pathological fracture and 55 controls without pathological fracture, all 4 quantitative measures of FDG avidity were statistically different between cases and controls (P < 0.001). A total lesion glycolysis of 81 could differentiate between fracture and nonfracture patients with accuracy, sensitivity, and specificity of 0.83, 0.85, and 0.80, respectively.

CONCLUSIONS

Quantitative measures of FDG avidity may help identify breast cancer patients at high risk of subsequent pathological fracture of the proximal femur.

Prospective Evaluation of the Relationship Between Mechanical Stability and Response to Palliative Radiotherapy for Symptomatic Spinal Metastases

BACKGROUND

A substantial number of patients with spinal metastases experience no treatment effect from palliative radiotherapy. Mechanical spinal instability, due to metastatic disease, could be associated with failed pain control following radiotherapy. This study investigates the relationship between the degree of spinal instability, as defined by the Spinal Instability Neoplastic Score (SINS), and response to radiotherapy in patients with symptomatic spinal metastases in a multi-institutional cohort.

METHODS AND MATERIALS

The SINS of 155 patients with painful thoracic, lumbar, or lumbosacral metastases from two tertiary hospitals was calculated using images from radiotherapy planning CT scans. Patient-reported pain response, available for 124 patients, was prospectively assessed. Pain response was categorized, according to international guidelines, as complete, partial, indeterminate, or progression of pain. The association between SINS and pain response was estimated by multivariable logistic regression analysis, correcting for predetermined clinical variables.

RESULTS

Of the 124 patients, 16 patients experienced a complete response and 65 patients experienced a partial response. Spinal Instability Neoplastic Score was associated with a complete pain response (adjusted odds-radio [ORadj] 0.78; 95% confidence interval [CI] 0.62-0.98), but not with an overall pain response (ORadj 0.94; 95% CI 0.81-1.10).

CONCLUSIONS

A lower SINS, indicating spinal stability, is associated with a complete pain response to radiotherapy. This supports the hypothesis that pain resulting from mechanical spinal instability responds less well to radiotherapy compared with pain from local tumor activity. No association could be determined between SINS and an overall pain response, which might indicate that this referral tool is not yet optimal for prediction of treatment outcome.

IMPLICATIONS FOR PRACTICE

Patients with stable painful spinal metastases, as indicated by a Spinal Instability Neoplastic Score (SINS) of 6 or lower, can effectively be treated with palliative external beam radiotherapy. The majority of patients with (impending) spinal instability, as indicated by a SINS score of 7 or higher, will achieve a (partial) response after palliative radiotherapy; however, some patients might require surgical intervention. Therefore, it is recommended to refer patients with a SINS score of 7 or higher to a spine surgeon to evaluate the need for surgical intervention.

Skeletal Complications and Mortality in Thyroid Cancer: A Population-Based Study

CONTEXT

Although bone is a common site for tumor metastases, the burden of bone events [bone metastases and skeletal-related events (SREs)] in patients with thyroid cancer is not well known.

OBJECTIVE

To measure the prevalence of bone events and their impact on mortality in patients with thyroid cancer.

PATIENTS, DESIGN, AND SETTING

We identified patients diagnosed with thyroid cancer between 1991 and 2011 from the linked Surveillance Epidemiology and End Results-Medicare dataset. Multivariable logistic regression was used to identify the risk factors for bone metastases and SREs. We used Cox proportional hazards regressions to assess the impact of these events on mortality, after adjusting for patient and tumor characteristics.

RESULTS

Of the 30,063 patients with thyroid cancer, 1173 (3.9%) developed bone metastases and 1661 patients (5.5%) developed an SRE. Compared with papillary thyroid cancer, the likelihood of developing bone metastases or an SRE was higher in follicular thyroid cancer [odds ratio (OR), 2.25; 95% confidence interval (CI), 1.85 to 2.74 and OR, 1.40; 95% CI, 1.15 to 1.68, respectively] and medullary thyroid cancer (OR, 2.16; 95% CI, 1.60 to 2.86 and OR, 1.62; 95% CI, 1.23 to 2.11, respectively). The occurrence of a bone event was associated with greater risk of overall and disease-specific mortality [hazard ratio (HR), 2.14; 95% CI, 1.94 to 2.36 and HR, 1.59; 95% CI, 1.48 to 1.71, respectively]. Bone events were a poor prognostic indicator even when compared with patients with other distant metastases (P < 0.001 and P < 0.001 for overall and disease-specific mortality, respectively).

CONCLUSIONS

Bone events in patients with thyroid cancer are a poor prognostic indicator. Patients with follicular and medullary thyroid cancers are at especially high risk for skeletal complications.

[Bone metastases : New aspects of pathogenesis and systemic therapy]

The occurrence of bone metastases, in particular secondary to breast and prostate cancer, represents a complex medical condition that is debilitating for affected patients. In order to provide an efficient and personalized therapy, an interdisciplinary treatment approach is mandatory; therefore, systemic pharmacological therapy represents a core element of the overall treatment concept. In terms of pathophysiology, the cancer cells cause a massive disturbance of the local bone microenvironment, which as a rule leads to activation of bone resorbing osteoclasts. In addition to bisphosphonates, which can be considered classical antiresorptive agents, the monoclonal receptor activator of nuclear factor-kappa B ligand (RANKL) antibody denosumab has been in use in clinical practice since 2011. The alpha-emitting radioisotope Alpharadin was also recently approved for the treatment of metastatic prostate cancer. This article provides a summary of the most recent knowledge on the pathogenesis of how cancer cells alter the bone microenvironment as well as a review of established and future systemic treatment options.

The Effect of Introducing the Spinal Instability Neoplastic Score in Routine Clinical Practice for Patients With Spinal Metastases

BACKGROUND

Stable spinal metastases are effectively treated with radiotherapy, whereas unstable spinal metastases often need surgical fixation followed by radiotherapy for local control. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic related instability with the goal of helping to guide referrals among oncology specialists. We compare the average degree of spinal instability between patients with spinal metastases referred for surgery or for radiotherapy and evaluate whether this difference changed after introduction of the SINS in clinical practice.

METHODS

All patients with spinal metastases treated with palliative surgery or radiotherapy in the period 2009-2013 were identified in two spine centers. For all patients, the SINS was scored on pretreatment imaging. The SINS before and after introduction of the SINS in 2011 were compared within the surgical and radiotherapy group. Furthermore, the overall SINS was compared between the two groups.

RESULTS

The overall SINS was significantly higher in the surgical group, with a mean SINS of 10.7 (median 11) versus 7.2 (median 8) for the radiotherapy group. The mean SINS decreased significantly for both groups after introduction of the SINS in clinical practice from 11.2 to 10.3 in the surgical group and from 8.4 to 7.2 in the radiotherapy group.

CONCLUSION

The SINS differed significantly between patients treated with surgery or radiotherapy. The introduction of SINS led to a decrease in SINS score for both groups, suggesting that using SINS in metastatic spinal disease increases awareness for instability and may subsequently result in earlier referrals for surgical intervention.

IMPLICATIONS FOR PRACTICE

Spinal metastases can present with varying degrees of mechanical instability. Because unstable spinal metastases may respond insufficiently to palliative radiotherapy and can lead to loss of ambulation, timely detection and appropriate referral are important. The Spinal Instability Neoplastic Score (SINS) may help physicians caring for patients with metastasized disease to identify spinal instability before the onset of neurological deficits. In this study, it was shown that the introduction of SINS in routine practice led to a decrease in spinal instability in radiotherapy and surgical cohorts. The use of SINS may increase awareness of instability and subsequently result in earlier referrals.

Survival and PSA-markers for mortality and metastasis in nonmetastatic prostate cancer treated with androgen deprivation therapy

BACKGROUND

Few studies have examined the risk of developing castration-resistant prostate cancer (CRPC), metastasis, and mortality among nonmetastatic prostate cancer (M0-PC) patients treated with androgen deprivation therapy (ADT). We estimated the incidence of these outcomes among M0-PC patients on ADT and identified prostate-specific antigen (PSA) based biomarkers for mortality and metastasis.

METHODS

This population-based cohort study included all nonmetastatic prostate cancer patients in Northern and Central Denmark Regions during 1997-2010, identified through registry data. Primary outcomes were metastasis, overall survival, and bone metastasis-free survival (BMFS). We estimated relative risks (RR) associated with PSA and PSA doubling-time (PSA-DT), measured as time-varying variables beginning at ADT treatment start.

RESULTS

We included 2494 M0-PC patients treated with ADT, of whom 1617 (80%) developed CRPC during follow-up. One-fourth of the patients developed metastases within 5 years; bone metastases (BM) accounted for 81% of all metastases. Median survival time was 4.4 years. Compared with PSA <8 ng/mL, PSA ≥8 ng/mL was associated with an adjusted RR of 14.0 (95% confidence interval [CI]: 10.2, 19.0) for BM, 4.4 (CI: 3.9, 5.0) for all-cause mortality, and RR of 4.8 (CI: 4.3, 5.4) for the inverse of BMFS. PSA-DT ≤6 months was associated with an adjusted RR of 7.6 (95% CI: 6.1, 9.5) for BM, RR of 5.9 (CI: 5.2, 6.6) for all-cause mortality, and RR 6.6 (CI: 5.9, 7.4) for the inverse of BMFS.

CONCLUSIONS

PSA ≥8 ng/mL and PSA-DT ≤6 months are strong predictors of mortality and bone metastasis. The poor prognosis observed in this study may reflect inclusion of patients with severe prostate cancer by requiring repeated PSA measurements.

(223)Ra and other bone-targeting radiopharmaceuticals-the translation of radiation biology into clinical practice

Osseous metastases are a source of significant morbidity for patients with a variety of cancers. Radiotherapy is well established as an effective means of palliating symptoms associated with such metastases. The role of external beam radiotherapy is limited where sites of metastases are numerous and widespread. Low linear energy transfer (LET) radionuclides have been utilized to allow targeted delivery of radiotherapy to disparate sites of disease, with evidence of palliative benefit. More recently, the bone targeting, high LET radionuclide (223)Ra has been shown to not only have a palliative effect but also a survival prolonging effect in metastatic, castration-resistant prostate cancer with bone metastases. This article reviews the different radionuclide-based approaches for targeting bone metastases, with an emphasis on (223)Ra, and key elements of the underlying radiobiology of these that will impact their clinical effectiveness. Consideration is given to the remaining unknowns of both the basic radiobiological and applied clinical effects of (223)Ra as targets for future research.

Metastatic tumors to the jaws and mouth

Metastatic dissemination to the oral cavity is rare and is usually the evidence of a wide spread disease with an average survival rate of 7 months. In almost a quarter of the cases, oral metastasis was found to be the first indication of an occult malignancy at a distant site. Metastatic lesions can be found anywhere in the oral cavity, however, the jaw bones with the molar area is the most frequently involved site. In the oral soft tissues, the gingiva is the most common site, suggesting the possible role of inflammation in the attraction of metastatic deposits. The most common primary malignancies presenting oral metastases were the lung, kidney, liver, and prostate for men, and breast, female genital organs, kidney, and colo-rectum for women. Most patients with jawbone metastasis complain of swelling, pain, and paresthesia. An exophytic lesion is the most common clinical presentation of metastatic lesions in the oral soft tissues. Early lesions, mainly those located in the gingiva, may resemble a hyperplastic or reactive lesion. Once a lesion is recognized as metastasis, the primary tumor site should be identified following clinical, radiological and histopathological investigations. If standardized diagnostic workup fails to detect the site of origin, then the term carcinoma of unknown primary is applied. Personalized medicine tools such as tissue-of-origin assays should be applied, either by immunohistochemical testing or by molecular-profiling methods as these may lead to a more favorable outcome.

Clinical and economic burden of bone metastasis and skeletal-related events in prostate cancer

PURPOSE OF REVIEW

We review the clinical trials and observational studies literature regarding the clinical and economic burden of bone metastasis and skeletal-related events (SREs) in prostate cancer, and discuss current gaps in understanding the impact of bone metastasis in this disease.

RECENT FINDINGS

Trial data indicate that SREs occur in half of prostate cancer patients with bone metastasis in the absence of treatment, and 30-45% among those who receive bone-modifying agents. In the United States, the cost of SRE ranged from $7553 per radiation episode to $88 838 per bone surgery episode. Prevalence of SRE, time to SRE occurrence, and cost of SRE varied across studies because of differences in study populations, follow-up period, and the algorithm used to measure SRE. There is limited evidence on the clinical and economic impact by SRE subtype. Information regarding patient-reported outcomes and costs from the patient's perspective is lacking.

SUMMARY

Bone metastasis and SREs in prostate cancer patients are associated with considerable morbidity, reduced survival, and substantial economic burden. Consistent study methodology, particularly the measurement of SREs, is necessary to allow comparison of estimates across studies. The inclusion of patient-centered clinical and economic outcomes in future research will provide pertinent information regarding the burden of bone metastasis and SREs.

Endocrine aspects of bone metastases

Skeletal lesions are a frequent complication of breast and prostate cancer and a hallmark of multiple myeloma. Endocrine and paracrine factors modulate various aspects of bone metastases, including tumour proliferation, skeletal susceptibility to tumour homing, the microenvironment needed to support tumour persistence, and the initiation of a vicious cycle between tumour and bone-resident cells that further promotes tumour growth. Endocrine changes, such as oestrogen or vitamin D deficiency, contribute to a fertile bone microenvironment that might promote bone metastases. Bone health could be impaired further by existing cancer treatments, especially sex hormone deprivation. In this Review, we discuss the effect of hormones and associated local factors on cross-talk between bone metabolism and tumour biology. We review the biology of osteolytic and osteosclerotic lesions, with a focus on endocrine aspects, and outline potential therapeutic targets. We also summarise endocrine aspects of the pathogenesis and clinical presentation of bone metastases and provide an update on existing and future treatments.