Mortality following bone metastasis and skeletal-related events among men with prostate cancer: a population-based analysis of US Medicare beneficiaries, 1999-2006

Notch activation promotes bone metastasis via SPARC inhibition in adenoid cystic carcinoma

OBJECTIVES

We aimed to investigate bone metastasis induced by Notch signalling pathway dysregulation and to demonstrate that SPARC is a potential therapeutic target in adenoid cystic carcinoma (AdCC) with Notch dysregulation.

MATERIALS AND METHODS

This retrospective study enrolled 144 AdCC patients. RNA-sequencing and enrichment analyses were performed using 32 AdCC samples. Osteonectin/SPARC and the Notch activation indicator Notch intracellular domain (NICD) were detected using immunohistochemistry. Cell proliferation and migration assays were conducted using stably NICD over-expressing cells. The effect of SPARC on osteoclast differentiation in NICD cells was investigated using western blotting, quantitative reverse transcription PCR, tartrate-resistant acid phosphatase staining and resorption assays.

RESULTS

RNA-sequencing analysis showed that genes down-regulated in Notch-mutant AdCCs, such as SPARC, were enriched in ossification and osteoblast differentiation. Most (75/110, 68.2%) Notch1-wild-type AdCCs showed SPARC over-expression, whereas 30 out of 34 (88.2%) Notch1-mutant tumours showed low SPARC expression. SPARC over-expression was then found negatively to be correlated with NICD expression in 144 AdCCs. NICD over-expression promoted cell growth, migration and osteoclast differentiation, which could be partly reversed by exogenous SPARC.

CONCLUSIONS

Notch activation in AdCC contributes to bone metastasis through SPARC inhibition. The study results suggest that SPARC may represent a prognostic biomarker and potential therapeutic target.

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.

Determinants of Bone-Modifying Agent Prescribing for Metastatic Castration-Resistant Prostate Cancer in a National Health Care Delivery System

PURPOSE

Despite guidelines recommending bone-modifying agents (BMAs) to decrease skeletal-related events (SREs) in men with metastatic castration-resistant prostate cancer (mCRPC), BMAs are underutilized. In this retrospective cohort study, we report the factors associated with BMA use in a national health care delivery system.

METHODS

We used the Veterans Affairs Corporate Data Warehouse to identify men with mCRPC between 2010 and 2017. BMA prescribing frequency was evaluated, and the association between patient- and disease-specific factors with BMA use was assessed using multivariable logistic regression.

RESULTS

Among 3,980 men identified with mCRPC (mean age 73.5 years, 29% Black), 47% received a BMA; median time to BMA from start of mCRPC treatment was 102 days. Factors associated with BMA use included previous BMA use (adjusted odds ratio [aOR], 7.81 [95% CI, 6.48 to 9.47]), diagnosis code for bone metastases (aOR, 1.26 [95% CI, 1.08 to 1.46]), and concomitant corticosteroid use (aOR, 1.53 [95% CI, 1.29 to 1.82]). Decreased BMA use was associated with advancing age (aOR, 0.85 per 10 years [95% CI, 0.78 to 0.92]), Charlson comorbidity index ≥2 (aOR, 0.76 [95% CI, 0.63 to 0.93]), Black race (aOR, 0.83 [95% CI, 0.70 to 0.98]), and decreased estimated glomerular filtration rate (eGFR; aOR, 0.19 [95% CI, 0.11 to 0.32] for eGFR 0-29 mL/minutes; aOR, 0.76 [95% CI, 0.64 to 0.91] for 30-59 mL/minutes).

CONCLUSION

Patients who are older, Black, or have more comorbidities are less likely to receive guideline concordant care to prevent SREs. These observations highlight the unique challenges of caring for patients with mCRPC and the need for future studies to increase BMA use in these populations.

A retrospective study on bone metastasis in dogs with advanced-stage solid cancer

OBJECTIVES

To review clinical characteristics, treatment, outcome and prognostic factors in dogs with solid cancer-bearing bone metastases.

MATERIALS AND METHODS

Records were reviewed from dogs with histologically-proven solid cancer and bone metastases. Clinicopathologic variables, bone metastases characteristics and skeletal-related events were recorded. Endpoints were time to bone metastases and survival.

RESULTS

Fifty dogs were included, 20 of them with synchronous and 30 of them with metachronous bone metastases. In the latter group, median time to diagnosis of bone metastases was 210 days (range, 30 to 1835). Most common primary cancer locations included mammary gland (n=6), spleen (n=5) and tonsil (n=5). Most common histotypes were carcinoma (n=32) and hemangiosarcoma (n=10). Nineteen dogs had multiple bones involvement, with humeri and vertebrae more commonly affected. Twenty-four dogs received antitumoural therapy, five symptomatic treatment and 21 were not treated. Overall median survival after bone metastases diagnosis was 30 days (range, 11 to 49); 83% of dogs died because of skeletal-related events. Lack of antitumoural therapy was significantly associated with shorter survival (hazard ratio: 2.7; 95% confidence interval: 1.3 to 5.6) and with increased risk of skeletal-related death (hazard ratio: 3.3; 95% confidence interval: 1.4 to 7.4). Dogs with endocrine/neuroendocrine tumours (odds ratio: 8.8; 95% confidence interval: 1.2 to 63.9), without appendicular metastases (odds ratio: 5.1; 95% confidence interval: 1.0 to 25.8), without extra-skeletal metastases (odds ratio: 5.2; 95% confidence interval: 1.1 to 24.5) and receiving antitumoural therapy (odds ratio: 14.8; 95% confidence interval: 1.7 to 131.4) had an increased chance of surviving more than 100 days.

CLINICAL SIGNIFICANCE

Bone metastases in dogs with solid cancers are associated with poor prognosis and a high risk of skeletal-related events. Treatment appears to have an impact on survival.

Can We Predict Prostate Cancer Metastasis Based on Biomarkers? Where Are We Now?

The incidence of prostate cancer (PC) has risen annually. PC mortality is explained by the metastatic disease (mPC). There is an intermediate scenario in which patients have non-mPC but have initiated a metastatic cascade through epithelial-mesenchymal transition. There is indeed a need for more and better tools to predict which patients will progress in the future to non-localized clinical disease or already have micrometastatic disease and, therefore, will clinically progress after primary treatment. Biomarkers for the prediction of mPC are still under development; there are few studies and not much evidence of their usefulness. This review is focused on tissue-based genomic biomarkers (TBGB) for the prediction of metastatic disease. We develop four main research questions that we attempt to answer according to the current evidence. Why is it important to predict metastatic disease? Which tests are available to predict metastatic disease? What impact should there be on clinical guidelines and clinical practice in predicting metastatic disease? What are the current prostate cancer treatments? The importance of predicting metastasis is fundamental given that, once metastasis is diagnosed, quality of life (QoL) and survival drop dramatically. There is still a need and space for more cost-effective TBGB tests that predict mPC disease.

Metastatic Castration-Resistant Prostate Cancer: Insights on Current Therapy and Promising Experimental Drugs

The therapeutic landscape of metastatic hormone sensitive and metastatic castration-resistant prostate cancer (mCRPC) is rapidly changing. We reviewed the current treatment options for mCRPC, with insights on new available therapeutic strategies. Chemotherapy with docetaxel or cabazitaxel (for patients progressing on docetaxel), as well as treatment with androgen receptor axis targeted therapies, and Radium-223 are well-established treatment options for patients with mCRPC. The advent of theragnostic in prostate cancer established Lutetium-177 (177Lu)-PSMA-617 as a new standard of care for PSMA-positive mCRPC previously treated with ARAT and taxane-based chemotherapy. Olaparib, a poly-ADP-ribose polymerase (PARP) inhibitor, is approved for selected patients with mCRPC progressed on ARATs and in combination with abiraterone acetate as first-line treatment for mCRPC. Immunotherapy showed limited efficacy in unselected patients with mCRPC and novel immunotherapy strategies need to be explored. The search for biomarkers is a growing field of interest in mCRPC, and predictive biomarkers are needed to support the choice of treatment and the development of tailored strategies.

Management of bone metastasis in prostate cancer

Progression of bone metastases is the primary cause of death in prostate cancer, and skeletal-related events (SREs), including pathologic fractures, spinal cord compression, radiation, or surgery to bone can impair patients' quality of life. Over the past decade, the development of cytotoxic agents, androgen-receptor-axis-targeted therapies (ARATs), and radioligand therapies has prolonged overall survival of prostate cancer patients with bone metastases and reduced the risk of SREs. The use of bone-modifying agents has also contributed to the reduced risk of SREs. Initial use of a cytotoxic agent, docetaxel, or an ARAT agent with androgen deprivation therapy (ADT) is the current approach to metastatic castration-sensitive prostate cancer. However, there is no consensus on the optimal medication for upfront use in combination with ADT, or on specific patient selection. Recently, next-generation imaging modalities, such as whole-body magnetic resonance imaging and prostate-specific membrane antigen-positron emission tomography have been utilized to detect bone metastases at an early stage. In addition, metastasis-directed therapy, such as stereotactic body radiation therapy, has been attempted. In the future, patients with bone metastatic prostate cancer will be divided into subgroups and their treatment options will be tailored to their specific characteristics.

Anticancer Potentials of the Lignan Magnolin: A Systematic Review

Magnolin is a naturally occurring, multi-bioactive lignan molecule with inherent anticancer effects. This study aims to summarize the botanical origins and anticancer properties of magnolin. For this, a recent (as of March 2023) literature review was conducted using various academic search engines, including PubMed, Springer Link, Wiley Online, Web of Science, Science Direct, and Google Scholar. All the currently available information about this phytochemical and its role in various cancer types has been gathered and investigated. Magnolin is a compound found in many different plants. It has been demonstrated to have anticancer activity in numerous experimental models by inhibiting the cell cycle (G1 and G2/M phase); inducing apoptosis; and causing antiinvasion, antimetastasis, and antiproliferative effects via the modulation of several pathways. In conclusion, magnolin showed robust anticancer activity against many cancer cell lines by altering several cancer signaling pathways in various non- and pre-clinical experimental models, making it a promising plant-derived chemotherapeutic option for further clinical research.

Understanding what matters to metastatic castration-resistant prostate cancer (mCRPC) patients when considering treatment options: A US patient preference survey

BACKGROUND

Understanding how patients perceive the efficacy, safety, and administrative burden of treatments for metastatic castration-resistant prostate cancer (mCRPC) can facilitate shared-decision making for optimal management. This study sought to elicit patient preferences for mCRPC treatments in the US.

METHODS

We conducted a cross-sectional survey using the discrete-choice experiment method. Participants were asked to state their choices over successive sets of treatment alternatives, defined by varying levels of treatment attributes: overall survival (OS), months until patients develop a fracture or bone metastasis, likelihood of requiring radiation to control bone pain, fatigue, nausea, and administration (i.e., oral/IV injection/IV infusion). Using mixed logit models, we determined the value (i.e., preference weights) that respondents placed on each attribute. Relative attribute importance (RAI) and marginal rates of substitution (MRS) were calculated to understand patients' willingness to make tradeoffs among different attributes.

RESULTS

The final data set numbered 160 participants, with a mean age of 71.6 years old and a mean of 8.96 years since prostate cancer diagnosis. Participants' treatment preferences were as follows: OS (RAI: 31%), bone pain control (23%), nausea (16%), delaying fracture or bone metastasis (15%), fatigue (11%), and administration (3%). The MRS demonstrated that respondents were willing to trade 1.9 months of OS to eliminate moderate nausea and 3.3 months of OS for a reduction in fatigue from severe to mild.

CONCLUSIONS

Improving OS is the highest priority for patients with mCRPC, but they are willing to trade some survival to reduce the risk of requiring radiation to control bone pain, delay a fracture or bone metastasis, and experience less severe nausea and fatigue.

Risk Evaluation of Bone Metastases and a Simple Tool for Detecting Bone Metastases in Prostate Cancer: A Population-Based Study

Introduction

Population-based estimates of the incidence and prognosis of bone metastases in prostate cancer (PC) are lacking. We aimed to characterize the incidence and risk of bone metastases and develop a simple tool for the prediction of bone metastases among patients with PC.

Methods

Data were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. A total of 75698 patients with PC with confirmed presence or absence of bone metastases at diagnosis between 1975 and 2019 in the United States were used for analysis. Data were stratified by age, race, residence, median income, prostate-specific antigen (PSA) values, tumor size, distant metastatic history, and positive lymph node scores. Multivariable logistic and Cox regressions were performed to identify predictors of bone metastases and factors correlated with all-cause mortality. Classification tree analysis was performed to establish a model.

Results

After patients with PC with missing data were excluded, 75698 cases remained. Among these, 3835 patients had bone metastases. Incidence proportions were highest in patients with a high prostate-specific antigen (PSA) value (odds ratio (OR), 2.49; 95% confidence interval (CI), 1.35-4.35; p < 0.002). Multivariable Cox regression and risk analyses indicated that high PSA values (hazards ratio (HR), 19.8; 95% CI, 18.5-21.2; p < 0.001) and high positive lymph node scores (vs. score 0; HR, 8.65; 95% CI, 7.89-9.49; p < 0.001) were significant risk factors for mortality. Meanwhile, in the predication tree analysis, PSA values and lymph node scores were the most significant determining factors in two models. Median survival among the patients with PC was 78 months, but only 31 months among those with bone metastases.

Conclusion

Patients with PC with high PSA values or high positive lymph node scores were at a significantly higher risk of bone metastases. Our study may provide a simple and accurate tool to identify patients with PC at high risk of bone metastases based on population-based estimates.

Validation of Algorithms to Identify Bone Metastases Using Administrative Claims Data in a Japanese Hospital

BACKGROUND

Validated coding algorithms are essential to generate high-quality, real-world evidence from claims data studies.

OBJECTIVE

We aimed to evaluate the validity of the algorithms to identify patients with bone metastases using claims data from a Japanese hospital.

PATIENTS AND METHODS

This study used administrative claims data and electronic medical records at Juntendo University Hospital from April 2017 to March 2019. We developed two candidate claims-based algorithms to detect bone metastases, one based on diagnosis codes alone (Algorithm 1) and the other based on the combination of diagnosis and imaging test codes (Algorithm 2). Of the patients identified by Algorithm 1, 100 patients were randomly sampled. Among these 100 patients, 88 patients met the conditions of Algorithm 2; further, 12 additional patients were randomly sampled from those identified by Algorithm 2, thus obtaining a total of 100 patients for Algorithm 2. They were evaluated for their true diagnosis using the patient chart review as the gold standard. The positive predictive value (PPV) was calculated to assess the accuracy of each algorithm.

RESULTS

For Algorithm 1, 82 patients were analyzed after excluding 18 patients without diagnostic imaging reports. Of these, 69 patients were true positive by chart review, resulting in a PPV of 84.1% (95% confidence interval (CI) 74.5-90.6). For Algorithm 2, 92 patients were analyzed after excluding eight patients whose diagnoses were not judged by chart review. Of these, 76 patients were confirmed positive by chart review, yielding a PPV of 82.6% (95% CI 73.4-89.1).

CONCLUSION

Both claims-based algorithms yielded high PPVs of approximately 85%, with no improvement in PPV by adding imaging test conditions. The diagnosis code-based algorithm is sufficient and valid for identifying bone metastases in this Japanese hospital.

A Retrospective Comparative Study of Sodium Fluoride Na18F-PET/CT and 68Ga-PSMA-11 PET/CT in the Bone Metastases of Prostate Cancer Using a Volumetric 3-D Radiomic Analysis

Bone is the most common metastatic site in prostate cancer (PCa). 68Ga-PSMA-11 (or gozetotide) and sodium fluoride-18 (Na18F) are rather new radiopharmaceuticals for assessing PCa-associated bone metastases. Gozetotide uptake reflects cell membrane enzyme activity and the sodium fluoride uptake measures bone mineralization in advanced PCa. Here, we aim to characterize this difference and possibly provide a new method for patient selection in targeted therapies. Methods: The study consisted of 14 patients with advanced PCa (M group > 5 lesions), who had had routine PET/CT both with PSMA and NaF over consecutive days, and 12 PCa patients with no skeletal metastases (N). The bone regions in CT were used to coregister the two PET/CT scans. The whole skeleton volume(s) of interest (VOIs) were defined using the CT component of PET (HU > 150); similarly, the sclerotic/dense bone was defined as HU > 600. Additional VOIs were defined for PET, with pathological threshold values for PSMA (SUV > 3.0) and NaF (SUV > 10). Besides the pathological bone volumes measured with each technique (CT, NaF, and PSMA-PET) and their contemporaneous combinations, overlapping VOIs with the CT-based skeletal and sclerotic volumes were also recorded. Additionally, thresholds of 4.0, 6.0, and 10.0 were tested for SUVPSMA. Results: In group M, the skeletal VOI volumes were 8.77 ± 1.80 L, and the sclerotic bone volumes were 1.32 ± 0.50 L; in contrast, in group N, they were 8.73 ± 1.43 L (skeletal) and 1.23 ± 0.28 L (sclerosis). The total enzyme activity for PSMA was 2.21 ± 5.15 in the M group and 0.078 ± 0.053 in the N group (p < 0.0002). The total bone demineralization activity for NaF varied from 4.31 ± 6.17 in the M group and 0.24 ± 0.56 in group N (p < 0.0002). The pathological PSMA volume represented 0.44−132% of the sclerotic bone volume in group M and 0.55−2.3% in group N. The pathological NaF volume in those patients with multiple metastases represented 0.27−68% of the sclerotic bone volume, and in the control group, only 0.00−6.5% of the sclerotic bone volume (p < 0.0003). Conclusions: These results confirm our earlier findings that CT alone does not suit the evaluation of the extent of active skeletal metastases in PCa. PSMA and NaF images give complementary information about the extent of the active skeletal disease, which has a clinical impact and may change its management. The PSMA and NaF absolute volumes could be used for planning targeted therapies. A cut-off value 3.0 for SUVPSMA given here is the best correlation in the presentation of active metastatic skeletal disease.

Factors Influencing Outcome Post–Radium-223 Dichloride in Castrate Resistant Prostate Cancer: A Review of Some Real-World Challenges

Aim Radium-223 has been the first-approved targeted Alpha therapy agent. We retrospectively assessed different factors influencing the overall survival (OS) and patient management.

Setting and Design Thirty-two metastatic castration-resistant prostate cancer (mCRPC) patients' hematological parameters, number of cycles, performance status, and toxicities were evaluated for OS. Radium 223 dichloride (Radium-223) was administered every 4 weeks for a maximum of six cycles. Primary and secondary end points were OS, progression free survival (PFS), therapy toxicities, change in performance status, biochemical response, and skeletal-related events (SREs).

Materials and Methods Patients' median age was 77 years (range: 57–90 years) and median follow-up was 399 days (range: 5–1,761 days). A total of 163 cycles were administered in 32 patients, with 4 or less cycles in 8 patients (25%) and 5 or more cycles in 24 patients (75%). Among eight patients with 4 or less cycles, three patients died, of which two patients died due to neutropenic sepsis.

Statistical Analysis Mann–Whitney test was used to compare the cycle groups; Spearman's correlation coefficient was used to see the relation of different variables with OS. Log rank test was used for group comparison while Kaplan–Meier survivorship was used for OS.

Results Statistical correlation was seen between the number of cycles (p=0.037) and hemoglobin (p=0.028). Kaplan–Meier OS (p=0.038) was correlated with the number of cycles (≤ 4 cycles and ≥ 5 cycles). OS was 173 days in patients with one to four cycles, 226 days in five cycles, and 493 days in six cycles. Myelosuppression leading to stopping of full six cycles was seen in 7 of 32 patients (22%) and significantly correlated to inferior OS (p=0.048).

Conclusion Higher number of Radium-223 cycles was seen to be associated with better OS. Prior myelosuppression was associated with poor OS. Patients with better hematological profile were more likely to complete the maximum number of the cycles with a better OS.

Castration-resistant prostate cancer with bone metastases: toward the best therapeutic choice

The treatment landscape for metastatic castration-resistant prostate cancer has evolved extremely in recent years and several drug classes are now available. Nonetheless, the lack of validated predictive biomarkers makes therapeutic choice and the best sequential approach difficult. The location of the metastatic site could be a valid criterion for choosing among the treatment options available. Although bone remains the most frequent metastatic site and a possible target for many drugs, recent data suggest a profound shift in the disease spectrum with visceral metastases increasing incidence. This review describes the presently available and ongoing therapies for patients with CRPC and bone metastases, focusing on the role of bone metastases as a possible driver for selecting therapies in these patients.

Appropriate Patient Status for Ra-223 Treatment in the Treatment Sequence for Castration-resistant Prostate Cancer

BACKGROUND/AIM

Radium (Ra)-223 is widely used for treating castration-resistant prostate cancer (CRPC) with bone metastasis based on evidence of increased survival and decreased skeletal-related events. However, the timing of Ra-223 use in the treatment sequence of CRPC remains controversial. Therefore, this study aimed to explore the appropriate patient status for Ra-223 use in the CRPC treatment sequence by examining patients treated with Ra-223 from the time of CRPC diagnosis until death.

PATIENTS AND METHODS

The medical records of 67 CRPC patients with bone metastasis who were treated with Ra-223 at two institutes were retrospectively analysed. The impact of 13 factors from the time of CRPC diagnosis until death was analysed using univariate and multivariate Cox hazard ratio models to evaluate the appropriate patient status for Ra-223 treatment.

RESULTS

The median survival time following CRPC diagnosis for all the patient groups was 3.82 years. Univariate analysis identified a higher-than-normal alkaline phosphatase (ALP) level, bone scan indexes ≥2, and prostate-specific antigen (PSA) doubling time <3 months before Ra-223 treatment as predominant adverse prognostic factors. Ra-223 therapy discontinuation was not a significant factor. The survival of CRPC patients with these factors was significantly worse than that of patients without these factors. In the multivariate analysis, a higher-than-normal ALP level at the start of treatment was identified as a poor prognostic factor for mortality.

CONCLUSION

The appropriate patient status for Ra-223 use includes low bone metastasis burden and well-controlled PSA levels.

Newly Diagnosed Multiple Myeloma Patients with Skeletal-Related Events and Abnormal MRI Pattern Have Poor Survival Outcomes: A Prospective Study on 370 Patients

Contemporary information is sparse on the frequency of skeletal-related events (SREs) in multiple myeloma (MM) patients at a population-based level in the era of novel agents. In this context, we conducted this single-center, prospective, observational study to determine the incidence of SREs among newly diagnosed MMs (NDMM) and to explore the possible correlations with disease characteristics, imaging finding, and patient prognosis. A total of 370 patients with available baseline MRIs were included. Among them, 208 (56%) presented with at least one SRE at diagnosis. Fractures were the most common reported SREs (48%). The incidence of SREs at diagnosis was higher in patients with osteolytic lesions, abnormal MRI pattern, hypercalcemia, and at least 60% bone marrow infiltration by plasma cells. Importantly, the patients with normal MRI pattern, who did not present with SREs at diagnosis, had statistically significant improved median OS in comparison with the patients who had abnormal MRI patterns and/or the presence of SREs at diagnosis (9.3 vs. 6.6 years, p = 0.048). Our data, which represent one of a few systematic reports on the incidence and characteristics of SREs in the era of novel agents, was indicative of a high incidence of SREs at the time of MM diagnosis. Early detection of myeloma bone disease and tailored patient management are essential to optimize patient outcomes.

The cost impact of disease progression to metastatic castration-sensitive prostate cancer

BACKGROUND: Metastatic prostate cancer (PC) is associated with declining survival rates and increased health care expenditure. However, there are few studies quantifying these increased costs. OBJECTIVE: To estimate overall health care resource utilization and costs associated with progression to metastatic disease in Medicare or commercially insured patients with nonmetastatic castration-sensitive PC (nmCSPC) or previously undiagnosed PC. METHODS: In this retrospective, observational cohort study, we used data from the IBM MarketScan Commercial and MarketScan Medicare Supplemental Databases. Included patients were aged 18 years or older, had 2 or more health care claims associated with a diagnosis of PC, and had a diagnosis of metastatic disease (index date) between January 1, 2014, and December 31, 2016. Patients with PC were identified at index as either progressing from a localized disease state (nmCSPC) without evidence of castration resistance (progressors) or de novo metastatic without a prior PC diagnosis. Unadjusted all-cause direct health care costs for the 2-year pre-index period and up to 2 years post-index were summarized. Metastasis-related incremental all-cause direct health care costs were estimated using regression modeling to adjust for patient baseline characteristics, follow-up duration, and possible selection bias. RESULTS: We identified 3,854 patients who met the criteria for CSPC at metastasis: 2,766 Medicare patients (mean age 78.8 ± 7.6 years) and 1,088 commercial patients (mean age 57.6 ± 4.3 years), with de novo patients accounting for 28.9% and 34.5% of the 2 analysis populations, respectively. Mean unadjusted total all-cause health care costs over the 24-month pre-index period among progressors were $52,661 (Medicare) and $43,111 (commercial); those among de novo patients were $39,756 (Medicare) and $22,090 (commercial). Mean unadjusted post-index costs for progressors were $100,331 (Medicare) and $127,374 (commercial) over a mean follow-up duration of 14.63 and 18.41 months, respectively, and $124,538 (Medicare) and $173,408 (commercial) over a mean follow-up duration of 14.14 and 17.29 months for patients with de novo disease. After multivariate adjustment, incremental cost increases due to metastasis in patients with CSPC pre-index were estimated at $104,051 (Medicare) and $93,334 (commercial), assuming data are available for 24 months post-index. Allowing for variation in the postindex observation period, estimates were $71,308 (Medicare) and $82,336 (commercial). Among de novo patients, cost increases due to metastasis were estimated at $180,932 (Medicare) and $215,397 (commercial), assuming all patients have data for 24 months postindex. Allowing for variable follow-up, estimates were $113,253 (Medicare) and $161,714 (commercial). CONCLUSIONS: Development of metastatic CSPC is associated with considerable costs over a 24-month follow-up period. Cost increases are greater for de novo patients than for those who progressed from localized disease. DISCLOSURES: Q.-D. Trinh received personal fees from Astellas, Bayer, and Janssen and grants from Intuitive Surgical. L. Passos Chaves, Q. Feng, J. Zhu, and T. Abbott are employees of Astellas Pharma Global Development, Inc. R. Sandin is an employee of, and holds stock in, Pfizer AB. This study was funded by Astellas Pharma Inc. (Northbrook, IL) and Pfizer Inc., the codevelopers of enzalutamide. Astellas Pharma Inc. was involved in the study design, data collection, analysis, interpretation of data, and decision to present these results.

Epidemiology of bone metastases

BACKGROUND

This study evaluated the incidence of de novo bone metastasis across all primary cancer sites and their impact on survival by primary cancer site, age, race, and sex.

QUESTIONS/PURPOSES

Our objectives were (I) characterize the epidemiology of de novo bone metastasis with respect to patient demographics, (II) characterize the incidence by primary site, age, and sex (2010-2015), and (III) compare survival of de novo metastatic cancer patients with and without bone metastasis.

METHODS

This is a retrospective, population-based study using nationally representative data from the Surveillance, Epidemiology, and End Results program, 2010-2015. Incidence rates by year of diagnosis, annual percentage changes, Kaplan-Meier, univariate and multiple Cox regression models are included in the analysis.

RESULTS

Of patients with cancer in the SEER database, 5.1% were diagnosed with metastasis to bone, equaling ~18.8 per 100,000 bone metastasis diagnoses in the US per year (2010-2015). For adults >25, lung cancer is the most common primary site (2015 rate: 8.7 per 100,000) with de novo bone metastases, then prostate and breast primaries (2015 rates: 3.19 and 2.38 per 100,000, respectively). For patients <20 years old, endocrine cancers and soft tissue sarcomas are the most common primaries. Incidence is increasing for prostate (Annual Percentage Change (APC) = 4.6%, P < 0.001) and stomach (APC = 5.0%, P = 0.001) cancers. The presence of de novo bone metastasis was associated with a limited reduction in overall survival (HR = 1.02, 95%, CI = [1.01-1.03], p < 0.001) when compared to patients with other non-bone metastases.

CONCLUSION

The presence of bone metastasis versus metastasis to other sites has disease site-specific impact on survival. The incidence of de novo bone metastasis varies by age, sex, and primary disease site.

Pharmacologic management of metastatic bone disease

Bone is a common site of metastases, particularly in advanced breast and prostate cancer. Skeletal related events associated with bone metastases include pathologic fracture, need for surgery/radiation to bone and cord compression. These events cause significant morbidity and mortality. Bisphosphonates as well as denosumab act on the bone microenvironment and reduce the rate of skeletal related events by approximately 25%-40%. Hence, these therapies are an important adjunctive therapy in cancer care. Despite the established efficacy and recommendations for their use in many international guidelines, these bone modifying agents are underutilized. This review examines the currently available guidelines on bone modifying agents in metastatic bone disease and summarizes their efficacy, risk and comparative benefits.

Radiomics for detecting prostate cancer bone metastases invisible in CT: a proof-of-concept study

OBJECTIVES

To investigate, in patients with metastatic prostate cancer, whether radiomics of computed tomography (CT) image data enables the differentiation of bone metastases not visible on CT from unaffected bone using 68 Ga-PSMA PET imaging as reference standard.

METHODS

In this IRB-approved retrospective study, 67 patients (mean age 71 ± 7 years; range: 55-84 years) showing a total of 205 68 Ga-PSMA-positive prostate cancer bone metastases in the thoraco-lumbar spine and pelvic bone being invisible in CT were included. Metastases and 86 68 Ga-PSMA-negative bone volumes in the same body region were segmented and further post-processed. Intra- and inter-reader reproducibility was assessed, with ICCs < 0.90 being considered non-reproducible. To account for imbalances in the dataset, data augmentation was performed to achieve improved class balance and to avoid model overfitting. The dataset was split into training, test, and validation set. After a multi-step dimension reduction process and feature selection process, the 11 most important and independent features were selected for statistical analyses.

RESULTS

A gradient-boosted tree was trained on the selected 11 radiomic features in order to classify patients' bones into bone metastasis and normal bone using the training dataset. This trained model achieved a classification accuracy of 0.85 (95% confidence interval [CI]: 0.76-0.92, p < .001) with 78% sensitivity and 93% specificity. The tuned model was applied on the original, non-augmented dataset resulting in a classification accuracy of 0.90 (95% CI: 0.82-0.98) with 91% sensitivity and 88% specificity.

CONCLUSION

Our proof-of-concept study indicates that radiomics may accurately differentiate unaffected bone from metastatic bone, being invisible by the human eye on CT.

KEY POINTS

• This proof-of-concept study showed that radiomics applied on CT images may accurately differentiate between bone metastases and metastatic-free bone in patients with prostate cancer. • Future promising applications include automatic bone segmentation, followed by a radiomics classifier, allowing for a screening-like approach in the detection of bone metastases.

The presenting dental status of solid tumours with bone metastases requiring bone-targeting agents - part 3: prostate cancer

Introduction Metastatic prostate cancer (MPC) patients due to receive bone-targeting agents (BTAs) are expected to undertake a dental assessment before commencing. The aim of this study was to determine the dental status of this tumour group and understand the challenges the dental practitioner faces in attempting to achieve 'dental fitness'.Materials and methods Data were retrospectively collected from a dedicated pre-BTA dental assessment clinic and analysed for MPC. Statistical analysis and observational data were used to compare patient and tumour demographics.Results A total of 111 patients were included in this cohort, with the majority of patients presenting with only bone metastases (BM) and no additional metastatic sites. On average, MPC patients presented with 19.3 teeth and were below the threshold for functional dentition. The 75-84-year-old age group had the worst horizontal bone loss score and subsequently lose six teeth over a decade (p = 0.001). In addition, all MPC tumour sub-categories showed favourable survival rates.Conclusion MPC patients have a high dental burden on presentation, likely associated with their age. Favourable survival prospects and the cumulation of BTAs and dental disease would suggest a heightened risk of medication-related osteonecrosis of the jaw in this group compared to many other tumour sites.

Systemic effects of abnormal bone resorption on muscle, metabolism, and cognition

Skeletal tissue is dynamic, undergoing constant remodeling to maintain musculoskeletal integrity and balance in the human body. Recent evidence shows that apart from maintaining homeostasis in the local microenvironment, the skeleton systemically affects other tissues. Several cancer-associated and noncancer-associated bone disorders can disrupt the physiological homeostasis locally in the bone microenvironment and indirectly contribute to dysregulation of systemic body function. The systemic effects of bone on the regulation of distant organ function have not been widely explored. Recent evidence suggests that bone can interact with skeletal muscle, pancreas, and brain by releasing factors from mineralized bone matrix. Currently available bone-targeting therapies such as bisphosphonates and denosumab inhibit bone resorption, decrease morbidity associated with bone destruction, and improve survival. Bisphosphonates have been a standard treatment for bone metastases, osteoporosis, and cancer treatment-induced bone diseases. The extraskeletal effects of bisphosphonates on inhibition of tumor growth are known. However, our knowledge of the effects of bisphosphonates on muscle weakness, hyperglycemia, and cognitive defects is currently evolving. To be able to identify the molecular link between bone and distant organs during abnormal bone resorption and then treat these abnormalities and prevent their systemic effects could improve survival benefits. The current review highlights the link between bone resorption and its systemic effects on muscle, pancreas, and brain.

Detection and Segmentation of Pelvic Bones Metastases in MRI Images for Patients With Prostate Cancer Based on Deep Learning

Objective

To establish and evaluate the 3D U-Net model for automated segmentation and detection of pelvic bone metastases in patients with prostate cancer (PCa) using diffusion-weighted imaging (DWI) and T1 weighted imaging (T1WI) images.

Methods

The model consisted of two 3D U-Net algorithms. A total of 859 patients with clinically suspected or confirmed PCa between January 2017 and December 2020 were enrolled for the first 3D U-Net development of pelvic bony structure segmentation. Then, 334 PCa patients were selected for the model development of bone metastases segmentation. Additionally, 63 patients from January to May 2021 were recruited for the external evaluation of the network. The network was developed using DWI and T1WI images as input. Dice similarity coefficient (DSC), volumetric similarity (VS), and Hausdorff distance (HD) were used to evaluate the segmentation performance. Sensitivity, specificity, and area under the curve (AUC) were used to evaluate the detection performance at the patient level; recall, precision, and F1-score were assessed at the lesion level.

Results

The pelvic bony structures segmentation on DWI and T1WI images had mean DSC and VS values above 0.85, and the HD values were <15 mm. In the testing set, the AUC of the metastases detection at the patient level were 0.85 and 0.80 on DWI and T1WI images. At the lesion level, the F1-score achieved 87.6% and 87.8% concerning metastases detection on DWI and T1WI images, respectively. In the external dataset, the AUC of the model for M-staging was 0.94 and 0.89 on DWI and T1WI images.

Conclusion

The deep learning-based 3D U-Net network yields accurate detection and segmentation of pelvic bone metastases for PCa patients on DWI and T1WI images, which lays a foundation for the whole-body skeletal metastases assessment.

Mechanisms, Diagnosis and Treatment of Bone Metastases

Bone and bone marrow are among the most frequent metastatic sites of cancer. The occurrence of bone metastasis is frequently associated with a dismal disease outcome. The prevention and therapy of bone metastases is a priority in the treatment of cancer patients. However, current therapeutic options for patients with bone metastatic disease are limited in efficacy and associated with increased morbidity. Therefore, most current therapies are mainly palliative in nature. A better understanding of the underlying molecular pathways of the bone metastatic process is warranted to develop novel, well-tolerated and more successful treatments for a significant improvement of patients' quality of life and disease outcome. In this review, we provide comparative mechanistic insights into the bone metastatic process of various solid tumors, including pediatric cancers. We also highlight current and innovative approaches to biologically targeted therapy and immunotherapy. In particular, we discuss the role of the bone marrow microenvironment in the attraction, homing, dormancy and outgrowth of metastatic tumor cells and the ensuing therapeutic implications. Multiple signaling pathways have been described to contribute to metastatic spread to the bone of specific cancer entities, with most knowledge derived from the study of breast and prostate cancer. However, it is likely that similar mechanisms are involved in different types of cancer, including multiple myeloma, primary bone sarcomas and neuroblastoma. The metastatic rate-limiting interaction of tumor cells with the various cellular and noncellular components of the bone-marrow niche provides attractive therapeutic targets, which are already partially exploited by novel promising immunotherapies.

Influences of the 3D microenvironment on cancer cell behaviour and treatment responsiveness: A recent update on lung, breast and prostate cancer models

The majority of in vitro studies assessing cancer treatments are performed in two-dimensional (2D) monolayers and are subsequently validated in in vivo animal models. However, 2D models fail to accurately model the tumour microenvironment. Furthermore, animal models are not directly applicable to mimic the human scenario. Three-dimensional (3D) culture models may help to address the discrepancies of 2D and animal models. When cancer cells escape the primary tumour, they can invade at distant organs building secondary tumours, called metastasis. The development of metastasis leads to a dramatic decrease in the life expectancy of patients. Therefore, 3D systems to model the microenvironment of metastasis have also been developed. Several studies have demonstrated changes in cell behaviour and gene expression when cells are cultured in 3D compared to 2D and concluded a better comparability to cells in vivo. Of special importance is the effect seen in response to anti-cancer treatments as models are built primarily to serve as drug-testing platforms. This review highlights these changes between cancer cells grown in 2D and 3D models for some of the most common cancers including lung, breast and prostate tumours. In addition to models aiming to mimic the primary tumour site, the effects of 3D cell culturing in bone metastasis models are also described. STATEMENT OF SIGNIFICANCE: Most in vitro studies in cancer research are performed in 2D and are subsequently validated in in vivo animal models. However, both models possess numerous limitations: 2D models fail to accurately model the tumour microenvironment while animal models are expensive, time-consuming and can differ considerably from humans. It is accepted that the cancer microenvironment plays a critical role in the disease, thus, 3D models have been proposed as a potential solution to address the discrepancies of 2D and animal models. This review highlights changes in cell behaviour, including proliferation, gene expression and chemosensitivity, between cancer cells grown in 2D and 3D models for some of the most common cancers including lung, breast and prostate cancer as well as bone metastasis.

Suppression of cancer-associated bone loss through dynamic mechanical loading

Patients afflicted with or being treated for cancer constitute a distinct and alarming subpopulation who exhibit elevated fracture risk and heightened susceptibility to developing secondary osteoporosis. Cancer cells uncouple the regulatory processes central for the adequate regulation of musculoskeletal tissue. Systemically taxing treatments to target tumors or disrupt the molecular elements driving tumor growth place considerable strain on recovery efforts. Skeletal tissue is inherently sensitive to mechanical forces, therefore attention to exercise and mechanical loading as non-pharmacological means to preserve bone during treatment and in post-treatment rehabilitative efforts have been topics of recent focus. This review discusses the dysregulation that cancers and the ensuing metabolic dysfunction that confer adverse effects on musculoskeletal tissues. Additionally, we describe foundational mechanotransduction pathways and the mechanisms by which they influence both musculoskeletal and cancerous cells. Functional and biological implications of mechanical loading at the tissue and cellular levels will be discussed, highlighting the current understanding in the field. Herein, in vitro, translational, and clinical data are summarized to consider the positive impact of exercise and low magnitude mechanical loading on tumor-bearing skeletal tissue.

Risk Scoring System for Ra-223 Discontinuation and Its Effect on Prognosis: A Retrospective Study

BACKGROUND/AIM

Radium-223 therapy prolongs overall survival in castration-resistant prostate cancer (CRPC) patients with bone metastasis. Patients who are unable to complete six courses of radium-223 therapy reportedly have a poor prognosis. This study aimed to develop a risk score using the discontinuation factors of the above therapy modality.

PATIENTS AND METHODS

Seventy patients who received radium-223 therapy for metastatic CRPC at two Japanese Institutions were evaluated. Univariate and multivariate analyses were performed to identify the discontinuation factors and determine the risk scores.

RESULTS

The median survival time was 24.3 and 9.5 months in patients who did and did not complete the therapy, respectively. Multivariate analysis revealed haemoglobin and prostate-specific antigen as key factors. A risk score was developed using these factors, and patients were stratified into three groups. The discontinuation rate and survival after radium-223 therapy were significantly different.

CONCLUSION

Our risk score may help evaluate the suitability of radium-223 in CRPC patients.

Bone health management in the continuum of prostate cancer disease: a review of the evidence with an expert panel opinion

Bone health impairment is a frequent detrimental consequence of the high bone tropism of prostate cancer (PCa) cells. It is further worsened by administration of androgen-deprivation therapy (ADT), the current standard of care in the management of advanced PCa, through a rapid and dramatic increase in bone turnover and body mass changes. As a result, patients may experience substantial pain and poor quality of life (QoL) and have an increased risk of death. Notwithstanding the importance of this issue, however, bone health preservation is not yet a widespread clinical goal in daily practice.

To address this urgent unmet need, following a thorough discussion of available data and sharing of their clinical practice experience, a panel of Italian experts in the field of bone health and metabolism formulated a number of practical advices for optimising the monitoring and treatment of bone health in men undergoing ADT during all phases of the disease. The rationale behind the venture was to raise awareness on the importance of bone preservation in this complex setting, while providing an instrument to support physicians and facilitate the management of bone health.

Current evidence regarding the effects on bone health of ADT, of novel hormone therapies (which improve progression delay, pain control and QoL while consistently carrying the risk of non-pathological fractures in both non-metastatic and metastatic PCa) and of bone turnover inhibitors (whose use is frequently suboptimal) is reviewed. Finally, the expert opinion to optimise bone health preservation is given.

Association of Concomitant Bone Resorption Inhibitors With Overall Survival Among Patients With Metastatic Castration-Resistant Prostate Cancer and Bone Metastases Receiving Abiraterone Acetate With Prednisone as First-Line Therapy

IMPORTANCE

Bone resorption inhibitors (BRIs) are recommended by international guidelines to prevent skeletal-related events (SREs) among patients with metastatic castration-resistant prostate cancer (mCRPC) and bone metastases. Abiraterone acetate with prednisone is currently the most common first-line therapy for the treatment of patients with mCRPC; however, the clinical impact of the addition of BRIs to abiraterone acetate with prednisone in this disease setting is unknown.

OBJECTIVE

To evaluate the association of the use of concomitant BRIs with overall survival (OS) and time to first SRE among patients with mCRPC and bone metastases receiving abiraterone acetate with prednisone as first-line therapy.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study collected data from 745 consecutive patients who began receiving abiraterone acetate with prednisone as first-line therapy for mCRPC with bone metastases between January 1, 2013, and December 31, 2016. Data were collected from 8 hospitals in Canada, Europe, and the US from June 15 to September 15, 2019.

EXPOSURES

Patients were classified by receipt vs nonreceipt of concomitant BRIs and subclassified by volume of disease (high volume or low volume, using definitions from the Chemohormonal Therapy Vs Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer [CHAARTED] E3805 study) at the initiation of abiraterone acetate with prednisone therapy.

MAIN OUTCOMES AND MEASURES

The primary end point was OS. The secondary end point was time to first SRE. The Kaplan-Meier method and Cox proportional hazards models were used.

RESULTS

Of the 745 men (median age, 77.6 years [interquartile range, 68.1-83.6 years]; 699 White individuals [93.8%]) included in the analysis, 529 men (71.0%) received abiraterone acetate with prednisone alone (abiraterone acetate cohort), and 216 men (29.0%) received abiraterone acetate with prednisone plus BRIs (BRI cohort). A total of 420 men (56.4%) had high-volume disease, and 276 men (37.0%) had low-volume disease. The median follow-up was 23.5 months (95% CI, 19.8-24.9 months). Patients in the BRI cohort experienced significantly longer OS compared with those in the abiraterone acetate cohort (31.8 vs 23.0 months; hazard ratio [HR], 0.65; 95% CI, 0.54-0.79; P < .001). The OS benefit in the BRI cohort was greater for patients with high-volume vs low-volume disease (33.6 vs 19.7 months; HR, 0.51; 95% CI, 0.38-0.68; P < .001). The BRI cohort also had a significantly shorter time to first SRE compared with the abiraterone acetate cohort (32.4 vs 42.7 months; HR, 1.27; 95% CI, 1.00-1.60; P = .04), and the risk of a first SRE was more than double in the subgroup with low-volume disease (HR, 2.29; 95% CI, 1.57-3.35; P < .001). In the multivariable analysis, concomitant BRIs use was independently associated with longer OS (HR, 0.64; 95% CI, 0.52-0.79; P < .001).

CONCLUSIONS AND RELEVANCE

In this study, the addition of BRIs to abiraterone acetate with prednisone as first-line therapy for the treatment of patients with mCRPC and bone metastases was associated with longer OS, particularly in patients with high-volume disease. These results suggest that the use of BRIs in combination with abiraterone acetate with prednisone as first-line therapy for the treatment of mCRPC with bone metastases could be beneficial.

An automatic framework for evaluating the vascular permeability of bone metastases from prostate cancer

Objectives.Vascular permeability can reflect tumorigenesis and metastasis. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can assess microvascular permeability by pharmacokinetic parameter estimation. Most estimation methods require manually selected arterial input function (AIF) or reference regions. However, the result will be unstable due to the annotation, which relies on personal experience. In this study, we propose an automatic framework for evaluating vascular permeability of bone metastases from prostate cancer without selecting AIF.Materials and methods.This retrospective study comprised of 15 prostate cancer patients with bone metastases. Based on clinical consensus for three typical DCE-MRI curve patterns, three characteristic curves as regularization constraints were introduced to the extended Tofts model (ETM) using clustering strategy, and the clustering-based blind identification of multichannel (CBM) framework was then proposed for pharmacokinetic parameter estimation. With automatic segmentation of the whole bone area, we obtained the estimation of the pharmacokinetic parameters in the bone area and quantified for bone metastases. Two experienced radiologists compared the CBM estimations with the diagnostic results and we compared the estimations with those of the ETM in bone metastasis regions to evaluate the feasibility of the CBM framework.Results.The higher signal regions ofK^transandK_epindicated the metastasis of prostate cancer, which is consistent with the cancer area marked by the radiologists. In addition, theK^transandK_epin bone metastasis regions were significantly higher than in normal bone regions (P < 0.001,P < 0.001). The consistency of estimation by using the CBM framework and conventional ETM method was confirmed by Bland-Altman analysis.Conclusion.The proposed CBM framework can provide a fully automatic and reliable quantitative estimation of vascular permeability for bone metastases in prostate cancer patients.

Incidence of bone metastases in patients with organ-specific cancers: A nationwide population-based cohort study

BACKGROUND

Bones are the third most common site of metastasis, although bone metastasis (BM) incidence varies widely. This study investigated the incidence of BM in the most common cancers in Taiwan to present the recent treatment landscape in patients with organ-specific cancers.

METHODS

Data from the National Health Insurance Research Database of Taiwan were used to identify adult patients diagnosed with organ-specific cancers between January 1, 2000 and December 31, 2015. Kaplan-Meier analysis was used to quantify cumulative BM incidence at follow-up. BM incidences associated with different cancers were calculated comprehensively and stratified by sex, age group and follow-up periods, and age- and sex-adjusted hazard ratios (HRs) of BM were calculated using multivariate Cox regression analysis.

RESULTS

Among 938 776 participants (mean follow-up, 9.2 years), liver (19.6%), colorectal (17.1%) and lung (15.1%) cancers were most commonly associated with BM. The mean interval between a primary cancer diagnosis and BM was 2 years. BM incidence varied widely among cancers; lung cancer (3213 per 10⁵ person-years) was associated with the highest BM risk, followed by oesophageal, prostate and breast cancer. HRs of BM were significantly higher for lung cancer (HR = 8.1) than for other cancers.

CONCLUSION

The estimated BM incidence provided insight into oncological clinical practice trends in the Asia-Pacific region. BM incidence may vary among populations. Understanding the principles of clinical evaluation in patients with cancer of unknown primary origin can facilitate appropriate treatment recommendations.

Which Way to Choose for the Treatment of Metastatic Prostate Cancer: A Case Report and Literature Review

Background

Prostate cancer (PCa) is the second most common cancer among males in the world and the majority of patients will eventually progress to the metastatic phase. How to choose an effective way for the treatment of metastatic PCa, especially in the later stage of the disease is still confusing. Herein we reported the case of a patient diagnosed with metastatic PCa and conducted a literature review on this issue.

Case Presentation

A 57-year-old man with metastatic PCa had been managed by Dr. J.P. since April 2012 when the patient was admitted to the Third Affiliated Hospital of Sun Yat-sen University by aggravating frequent urination and dysuria. The prostate-specific antigen (PSA) concentration was 140 ng/ml, and the diagnosis of PCa was confirmed by prostate biopsy, with Gleason score 4 + 5 = 9. Chest CT and bone scan indicated multiple metastases in the lungs and bones. Triptorelin, bicalutamide, zoledronic acid, and docetaxel were then administered, six cycles later, the metastatic tumors in the lungs disappeared and those in the bones lessened significantly, along with a remarkable reduction in PSA level (< 2 ng/ml). Intermittent androgen deprivation was subsequently conducted until August 2018, when the serum PSA level was found to be 250 ng/ml, again docetaxel 75 mg/m² was administered immediately but the patient was intolerant this time. Instead, abiraterone was administered until March 2019 because of intolerable gastrointestinal side-effects and increasing PSA level. In October 2019, the patient came to our center, a modified approach of docetaxel (day 1 40 mg/m² + day 8 35 mg/m²) was administered. Luckily, the PSA level decreased rapidly, the bone pain was greatly relieved, and no obvious side effects occurred. However, four cycles later, docetaxel failed to work anymore, the metastatic tumor in the liver progressed. We proposed several regimens as alternatives, but they were soon denied due to the high prices or unavailability or uncertain effect of the drugs. In addition, the patient’s condition deteriorated speedily and can no longer bear any aggressive treatment. Finally, the patient died of multiple organ failure in August 2020.

Conclusion

The experiences of this case provide valuable evidence and reference for the treatment choices of metastatic PCa, in some circumstances modified and advanced regimens may produce unexpected effects.

Real-world safety and effectiveness of radium-223 in Japanese patients with castration-resistant prostate cancer (CRPC) and bone metastasis: exploratory analysis, based on the results of post-marketing surveillance, according to prior chemotherapy status and in patients without concomitant use of second-generation androgen-receptor axis-targeted agents

BACKGROUND

Based on results from Japanese post-marketing surveillance, exploratory analyses were performed to investigate real-world outcomes of radium-223 for metastatic CRPC (mCRPC) according to patient characteristics.

METHODS

This non-interventional, prospective study enrolled mCRPC patients selected for radium-223 treatment in clinical practice. Six-month safety and effectiveness were evaluated in subgroups who had/had not received prior chemotherapy (prior-chemo/no prior-chemo groups), and a subgroup who had not received concomitant androgen-receptor axis-targeted agents (ARATs).

RESULTS

In the overall population (n = 296), the prior-chemo group (n = 126) tended to have more bone metastases, more analgesic use, and higher prostate-specific antigen values than the no prior-chemo group (n = 170). Incidences of treatment-emergent adverse events (TEAEs), drug-related TEAEs, and ≥ grade 3 drug-related hematological TEAEs were 47% vs. 53%, 25% vs. 29%, and 4% vs. 7% in the no prior-chemo and prior-chemo groups, respectively. Incidences of TEAEs (61%), drug-related TEAEs (36%), and ≥ grade 3 drug-related hematological events (12%) were numerically higher in 33 patients who had received two lines of prior chemotherapy. Multivariate analysis showed that two lines of prior chemotherapy, and hemoglobin, platelet, and lactate dehydrogenase values were baseline factors significantly related to ≥ grade 2 platelet count decreased. Safety and effectiveness in patients without concomitant ARATs (n = 201) were similar to those in the overall population.

CONCLUSION

In a real-life setting, radium-223 was well tolerated irrespective of prior chemotherapy, but relatively higher incidences of TEAEs and hematotoxicities were suggested in patients with two lines of prior chemotherapy, possibly reflecting more advanced disease. Radium-223 safety and effectiveness in patients without concomitant ARATs were favorable.

Identification of Key Gene Signatures Associated With Bone Metastasis in Castration-Resistant Prostate Cancer Using Co-Expression Analysis

About 80–90% of castration-resistant prostate cancer (CRPC) patients would develop bone metastasis. However, the molecular mechanisms of bone metastasis are still not clear. This study aimed to detect the differences between the tumor and normal samples in bone after metastatic colonization. Four transcriptional datasets (GSE32269, GSE101607, GSE29650, and GSE74685) were obtained from the GEO database. 1983 differentially expressed genes (DEGs) were first identified between tumor and normal marrow samples in GSE32269. Most of the top 10 up-regulated DEGs are related with prostate cancer, and the top 10 down-regulated DEGs are mainly related with bone development. Seven co-expression modules were then detected based on the 1469 DEGs shared by the four datasets. Three of them were found highly preserved among the four datasets. Enrichment analysis showed that the three modules were respectively enriched in Cell adhesion molecules (CAMs), Leukocyte transendothelial migration and cell cycle, which might play significantly important roles in the tumor development in bone marrow. Ten, 17, and 99 hub genes for each module were then identified. And four genes (C3AR1, IL10RA, LY86, and MS4A6A) were detect to be tightly related to progression of bone metastatic CRPC. ROC curve was plotted and AUC was calculated to distinguish tumor and normal bone marrow samples as well as bone and non-bone metastatic CRPCs. The present study identified key genes and modules involved in bone metastatic CRPCs, which may provide new insights and biomarkers for understanding of the molecular mechanisms of bone metastatic CRPC.

State-of-the-art imaging for diagnosis of metastatic bone disease

Metastatic bone disease (MBD) is common—it is detected in up to 65–75% of patients with breast or prostate cancer, in over 35% of patients with lung cancer; and almost all patients with symptomatic multiple myeloma have focal lesions or a diffuse bone marrow infiltration. Metastatic bone disease can cause a variety of symptoms and is often associated with a poorer prognosis, with high social and health-care costs. Population-based cohort studies confirm significantly increased health-care utilization costs in patients presenting with cancer with MBD compared with those without MBD. The prolonged survival of patients with bone metastasis thanks to advances in therapy presents an opportunity for better treatments for this patient cohort. Early and accurate diagnosis of bone metastases is therefore crucial. The patterns and presentation of MBD are quite heterogeneous and necessitate good knowledge of the possibilities and limitations of each imaging modality. Here, we review the state-of-the-art imaging techniques, assess the need for evidence-based and cost-effective patient care pathways, and advocate multidisciplinary management based on collaborations between orthopedic surgeons, pathologists, oncologists, radiotherapists, and radiologists aimed at improving patient outcomes. Radiologists play a key role in this multidisciplinary approach to decision-making through correlating the tumor entity, the tumor biology, the impact on the surrounding tissues and progression, as well as the overall condition of the patient. This approach helps to choose the best patient-tailored imaging plan advocating a “choose wisely” strategy throughout the initial diagnosis, minimally invasive treatment procedures, as well as follow-up care plans.

A Retrospective Comparative Study of Sodium Fluoride (NaF-18)-PET/CT and Fluorocholine (F-18-CH) PET/CT in the Evaluation of Skeletal Metastases in Metastatic Prostate Cancer Using a Volumetric 3-D Radiomics Analysis

Bone metastases are common in prostate cancer (PCa). Fluorocholine-18 (FCH) and sodium fluoride-18 (NaF) have been used to assess PCa associated skeletal disease in thousands of patients by demonstrating different mechanism of uptake-cell membrane (lipid) synthesis and bone mineralization. Here, this difference is characterized quantitatively in detail. Our study cohort consisted of 12 patients with advanced disease (> 5 lesions) (M) and of five PCa patients with no skeletal disease (N). They had routine PET/CT with FCH and NaF on consecutive days. Skeletal regions in CT were used to co-register the two PET/CT scans. Bone 3-D volume of interest (VOI) was defined on the CT of PET with a threshold of HU > 150, and sclerotic/dense bone as HU > 600, respectively. Additional VOIs were defined on PET uptake with the threshold values on both FCH (SUV > 3.5) and NaF (SUV > 10). The pathologic skeletal volumes for each technique (CT, HU > 600), NaF (SUV > 10) and FCH (SUV > 3.5) were developed and analyzed. The skeletal VOIs varied from 5.03 L to 7.31 L, whereas sclerotic bone VOIs were from 0.88 L to 2.99 L. Total choline kinase (cell membrane synthesis) activity for FCH (TCA) varied from 0.008 to 4.85 [kg] in M group and from 0.0006 to 0.085 [kg] in N group. Total accelerated osteoblastic (bone demineralization) activity for NaF (TBA varied from 0.25 to 13.6 [kg] in M group and varied from 0.000 to 1.09 [kg] in N group. The sclerotic bone volume represented only 1.86 ± 1.71% of the pathologic FCH volume and 4.07 ± 3.21% of the pathologic NaF volume in M group, and only 0.08 ± 0.09% and 0.18 ± 0.19% in N group, respectively. Our results suggest that CT alone cannot be used for the assessment of the extent of active metastatic skeletal disease in PCa. NaF and FCH give complementary information about the activity of the skeletal disease, improving diagnosis and disease staging.

A Retrospective Observational Analysis of Overall Survival with Sipuleucel-T in Medicare Beneficiaries Treated for Advanced Prostate Cancer

INTRODUCTION

Since sipuleucel-T approval in 2010, the treatment landscape for metastatic castration-resistant prostate cancer (mCRPC) now includes the androgen-receptor signaling pathway inhibitors (ASPIs) abiraterone acetate or enzalutamide. In 2013 and 2014, these oral agents were approved for use in men with metastatic prostate cancer who had minimal to no symptoms. We compared overall survival (OS) in men who received their first mCRPC treatment using the Medicare Fee-for-Service 100% administrative claims research dataset with patient-level linkage to the National Death Index.

METHODS

This retrospective cohort analysis (January 2013 to December 2017) included men who were chemo-naïve at treatment start in 2014 and who had continuous Medicare Parts A, B, and D eligibility during the 3-year observation period. We compared: first-line sipuleucel-T vs. first-line ASPIs and any-line sipuleucel-T vs. any-line ASPIs (without sipuleucel-T). We used a multivariable regression model to help control for potentially confounding factors while assessing survival outcomes.

RESULTS

The model included 6044 eligible men (average age 75-78 years) with similar disease severity; > 80% were white. Median OS, presented as sipuleucel-T vs. ASPI, was 35.2 vs. 20.7 months (n, 906 vs. 5092; any-line cohort) and 34.9 vs. 21.0 months (n, 647 vs. 4810; first-line cohort). Model outcomes indicated sipuleucel-T was associated with significantly prolonged OS compared with ASPIs: adjusted hazard ratio, 0.59 (95% CI 0.527-0.651) and 0.56 (0.494-0.627) for the any-line and first-line cohorts, respectively.

CONCLUSION

This analysis suggests use of sipuleucel-T at any time was associated with improved OS compared with ASPI use alone. Of note, these analyses are intended as descriptive rather than definitive as this dataset contains limited data on key clinical factors. While selection bias is a risk in secondary claims data, this research provides important insight into real-world treatment outcomes.

Revealing Prognostic Value of Skeletal-Related Parameters in Metastatic Castration-Resistant Prostate Cancer on Overall Survival: A Systematic Review and Meta-Analysis of Randomized Controlled Trial

BACKGROUND

The skeleton is a preferred site for prostate cancer metastasis, and once metastases occur, the disease becomes incurable. Increasing evidence indicates the prognostic value of skeletal-related parameters, but remains controversial.

OBJECTIVE

To perform a systematic review of the existing literature on assessing the prognostic value of alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BSAP), urinary N-telopeptide (uNTx), bone scan index (BSI), and Brief Pain Inventory Short Form (BPI-SF) score in castration-resistant prostate cancer (CRPC) patients with skeleton metastasis.

EVIDENCE ACQUISITION

PubMed, Web of Science, Cochrane Library, Medline, OVID, and Embase between 2010 and 2019 were reviewed. Key terms included randomized trials, prostate cancer, alkaline phosphatase, bone-specific alkaline phosphatase, urinary N-telopeptide, bone scan index, and Brief Pain Inventory Short Form. Data were collected, checked, and analyzed from December 2019 to March 2020. Hazard ratios (HRs) and overall survival (OS) were extracted to estimate the relationship between the above parameters and OS in patients with metastatic prostate cancer (mPCa).

EVIDENCE SYNTHESIS

A total of 1,055 studies were identified via initial screening, including 1,032 from database research and 23 from other sources. After deduplication, 164 records were further excluded according to titles and abstracts. The remaining 36 potential articles were carefully screened. In the end, 15 eligible studies syntheses, which were published between 2010 and 2019, comprised data for a total of 11,378 patients, whose mean age ranged from 66 to 72 years. The sample size ranged from 82 to 1,901 patients. And the median follow-up time ranged from 24 to 55 months. Based on 15 randomized controlled trials published between 2010 and 2019, higher ALP levels (HR = 1.60, 95% CI: 1.38-1.87 P < 0.001), higher BSAP levels (HR = 1.31, 95% CI: 1.11-1.54 P = 0.001), higher uNTx levels (HR = 1.40, 95% CI: 1.29-1.52 P < 0.001), BSI progression (HR = 1.18, 95% CI: 1.08-1.29 P < 0.001), and higher BPI-SF score (HR = 1.47, 95% CI: 1.35-1.61 P < 0.001) had an association with inferior OS.

CONCLUSIONS

Higher levels of ALP/BSAP and uNTx, a higher BPI-SF score, and progression of BSI predict inferior OS in patients with mCRPC. More randomized control trials are needed to investigate the promising value of these parameters.

Functional results and survival after surgery for peripheral skeletal metastasis: A 434-case multicenter retrospective series

INTRODUCTION

Peripheral skeletal metastasis (PSM) has a negative impact on quality of life. New treatments for the primary tumor or the osteolysis hold out hope of improved survival. The few published French series were small, and we therefore undertook a multicenter retrospective analysis of PSM surgery between 2005 and December 2016, with the aim of assessing: 1) rate and type of complications, 2) functional results, and 3) overall survival and corresponding risk factors.

HYPOTHESIS

The French data for clinical results, survival and complications are in agreement with the international literature.

MATERIALS AND METHOD

The series comprised 391 patients with 434 metastatic locations. There was female predominance: 247 women (63%). Two sites were treated in 46 patients (12%), and three in 5. The main etiologies were breast cancer (151/391: 39%), lung cancer (103/391: 26%) and kidney cancer (52/391: 13%). There was synchronous visceral metastasis in 166 patients (42.5%), other peripheral locations in 137 (35%) and spinal location in 142 (39%). One hundred (27%) had ASA score>3; 61 (16%) had WHO score>3. The reason for surgery was pathologic fracture (n=137: 35%). Locations were femoral (274: 70%), acetabular (58: 15%), humeral (40: 0%), tibial (12: 3%) or other (7: 2%).

RESULTS

There were surgery site complications in 41 patients (9.4%), including 13 surgery site infections, and general complications in 47 patients (11%), including 11 cases of thromboembolism, 6 of blood loss, 9 pulmonary complications and 6 perioperative deaths. Overall survival, taking all etiologies and sites together, was 10 months (range, 5 days to 9 years; 95% CI, 8-13 months), and significantly better in females (14 versus 6 months; p=0.01), under-65 year-olds (p=0.001), and in preventive surgery versus fractured PSM (p=0.001). Median survival was 22 months (95% CI, 17-28 months) after breast cancer, 3 months (95% CI, 2-5 months) after lung cancer, and 17 months (95% CI, 8-58 months) after kidney cancer. Preoperatively, walking was impossible for 143 patients (38%), versus 23 (6.5%) postoperatively; 229 patients (63.5%) could walk normally or nearly normally after surgery, versus 110 (28%) before. After surgery, 3 patients (6%) were not using their operated upper limb, versus 27 (45%) before; 30 patients (54%) had normal upper limb use after surgery, versus 8 (5%) before.

CONCLUSION

The study hypothesis was on the whole confirmed in terms of survival according to type of primary and whether surgery was indicated preventively or for fracture.

LEVEL OF EVIDENCE

IV, retrospective study without control group.

Dynamic changes of bone metastasis predict bone-predominant status to benefit from radium-223 dichloride for patients with castration-resistant prostate cancer

Background

To best employ radium‐223 dichloride (Ra‐223) for patients with castration‐resistant prostate cancer (CRPC) and bone metastasis, we investigated the bone‐predominant status in patients treated with Ra‐223.

Methods

We retrospectively evaluated 127 CRPC patients who underwent treatment with Ra‐223. The patients were divided into three groups based on the types of dynamic changes of bone metastasis between diagnosis and just before Ra‐223: (a) only known lesions; (b) de novo lesions; (c) new progressive lesions. We developed the risk assessment using predictive factors based on progression‐free survival (PFS).

Results

During the median follow‐up period of 10.4 months, the median PFS in the only known lesions group was 11.3 months compared to 8.1 months in the de novo lesions group and 5.1 months in the new progressive lesions group (P < .001). In multivariate analysis, the type of the new progressive lesions in bone metastasis (HR 1.45, 95% CI 1.13‐1.66, P = .003), performance status of >1 (HR 1.74, 95% CI 1.04‐2.89, P = .034), PSA value of >100 ng/mL (HR 1.59, 95% CI 1.02‐2.50, P = .043), and PSA doubling time (PSADT) of <3 months (HR 1.53, 95% CI 1.11‐2.03, P = .007) were independent unfavorable predictive factors for PFS. The risk assessment for PFS was highlighted when the type of dynamic changes of bone metastasis was combined with PSADT just before Ra‐223 treatment. This was associated with non‐bone metastasis progression, especially visceral metastasis, and overall survival.

Conclusions

Risk assessment in combination with dynamic changes of bone metastasis and PSADT determines the bone‐predominant metastasis type to benefit from Ra‐223.

[Effectiveness of Topical NSAIDs in a Gastric Cancer Patient with Bone Metastasis Pain during Therapy with Opioids and Oral NSAIDs]

Cancer patients often suffer from severe pain related to bone metastasis. We encountered a patient in whom the addition of topical non-steroidal anti-inflammatory drugs (NSAIDs) for persistent pain related to bone metastasis during therapy with opioids and oral NSAIDs reduced pain, improving activities of daily living (ADL). Fentanyl patches, celecoxib, denosumab, and topical NSAIDs (loxoprofen tape, felbinac) were administered to a 72-year-old patient with gastric cancer and pain related to bone metastasis. Pain control was favorable, with a numerical rating scale (NRS) score of 2 and Japanese version Support Team Assessment Schedule (STAS-J) score of 1. Intervention by pharmacists for the use of topical NSAIDs decreased both the NRS and STAS-J scores to zero, improving ADL. The results suggest that topical NSAIDs relieve bone-metastasis-related pain, improving ADL. When bone-metastasis-related pain is localized, the prescription of topical NSAIDs should be considered, and positive intervention by pharmacists regarding their usage should be promoted.

Targeting anti-cancer agents to bone using bisphosphonates

The skeleton is affected by numerous primary and metastatic solid and hematopoietic malignant tumors, which can cause localized sites of osteolysis or osteosclerosis that can weaken bones and increase the risk of fractures in affected patients. Chemotherapeutic drugs can eliminate some tumors in bones or reduce their volume and skeletal-related events, but adverse effects on non-target organs can significantly limit the amount of drug that can be administered to patients. In these circumstances, it may be impossible to deliver therapeutic drug concentrations to tumor sites in bones. One attractive mechanism to approach this challenge is to conjugate drugs to bisphosphonates, which can target them to bone where they can be released at diseased sites. Multiple attempts have been made to do this since the 1990s with limited degrees of success. Here, we review the results of pre-clinical and clinical studies made to target FDA-approved drugs and other antineoplastic small molecules to bone to treat diseases affecting the skeleton, including osteoporosis, metastatic bone disease, multiple myeloma and osteosarcoma. Results to date are encouraging and indicate that drug efficacy can be increased and side effects reduced using these approaches. Despite these successes, challenges remain: no drugs have gone beyond small phase 2 clinical trials, and major pharmaceutical companies have shown little interest in the approach to repurpose any of their drugs or to embrace the technology. Nevertheless, interest shown by smaller biotechnology companies in the technology suggests that bone-targeting of drugs with bisphosphonates has a viable future.

ACK1-AR and AR-HOXB13 signaling axes: epigenetic regulation of lethal prostate cancers

The androgen receptor (AR) is a critical transcription factor in prostate cancer (PC) pathogenesis. Its activity in malignant cells is dependent on interactions with a diverse set of co-regulators. These interactions fluctuate depending on androgen availability. For example, the androgen depletion increases the dependence of castration-resistant PCs (CRPCs) on the ACK1 and HOXB13 cell survival pathways. Activated ACK1, an oncogenic tyrosine kinase, phosphorylates cytosolic and nuclear proteins, thereby avoiding the inhibitory growth consequences of androgen depletion. Notably, ACK1-mediated phosphorylation of histone H4, which leads to epigenetic upregulation of AR expression, has emerged as a critical mechanism of CRPC resistance to anti-androgens. This resistance can be targeted using the ACK1-selective small-molecule kinase inhibitor (R)- 9b. CRPCs also deploy the bromodomain and extra-terminal domain protein BRD4 to epigenetically increase HOXB13 gene expression, which in turn activates the MYC target genes AURKA/AURKB. HOXB13 also facilitates ligand-independent recruitment of the AR splice variant AR-V7 to chromatin, compensating for the loss of the chromatin remodeling protein, CHD1, and restricting expression of the mitosis control gene HSPB8. These studies highlight the crosstalk between AR-ACK1 and AR-HOXB13 pathways as key mediators of CRPC recurrence.

Prostate cancer-derived exosomes promote osteoblast differentiation and activity through phospholipase D2

Prostate cancer (PCa) is the most frequent cancer in men aged 65 and over. PCa mainly metastasizes in the bone, forming osteosclerotic lesions, inducing pain, fractures, and nerve compression. Cancer cell-derived exosomes participate in the metastatic spread, ranging from oncogenic reprogramming to the formation of pre-metastatic niches. Moreover, exosomes were recently involved in the dialog between PCa cells and the bone metastasis microenvironment. Phospholipase D (PLD) isoforms PLD1/2 catalyze the hydrolysis of phosphatidylcholine to yield phosphatidic acid (PA), regulating tumor progression and metastasis. PLD is suspected to play a role in exosomes biogenesis. We aimed to determine whether PCa-derived exosomes, through PLD, interact with the bone microenvironment, especially osteoblasts, during the metastatic process. Here we demonstrate for the first time that PLD2 is present in exosomes of C4-2B and PC-3 cells. C4-2B-derived exosomes activate proliferation and differentiation of osteoblasts models, by stimulating ERK 1/2 phosphorylation, by increasing the tissue-nonspecific alkaline phosphatase activity and the expression of osteogenic differentiation markers. Contrariwise, when C4-2B exosomes are generated in the presence of halopemide, a PLD pan-inhibitor, they lose their ability to stimulate osteoblasts. Furthermore, the number of released exosomes diminishes significantly (-40%). When the PLD product PA is combined with halopemide, exosome secretion is fully restored. Taken together, our results indicate that PLD2 stimulates exosome secretion in PCa cell models as well as their ability to increase osteoblast activity. Thus, PLD2 could be considered as a potent player in the establishment of PCa bone metastasis acting through tumor cell derived-exosomes.

An agent-based model of prostate Cancer bone metastasis progression and response to Radium223

BACKGROUND

Bone metastasis is the most frequent complication in prostate cancer patients and associated outcome remains fatal. Radium223 (Rad223), a bone targeting radioisotope improves overall survival in patients (3.6 months vs. placebo). However, clinical response is often followed by relapse and disease progression, and associated mechanisms of efficacy and resistance are poorly understood. Research efforts to overcome this gap require a substantial investment of time and resources. Computational models, integrated with experimental data, can overcome this limitation and drive research in a more effective fashion.

METHODS

Accordingly, we developed a predictive agent-based model of prostate cancer bone metastasis progression and response to Rad223 as an agile platform to maximize its efficacy. The driving coefficients were calibrated on ad hoc experimental observations retrieved from intravital microscopy and the outcome further validated, in vivo.

RESULTS

In this work we offered a detailed description of our data-integrated computational infrastructure, tested its accuracy and robustness, quantified the uncertainty of its driving coefficients, and showed the role of tumor size and distance from bone on Rad223 efficacy. In silico tumor growth, which is strongly driven by its mitotic character as identified by sensitivity analysis, matched in vivo trend with 98.3% confidence. Tumor size determined efficacy of Rad223, with larger lesions insensitive to therapy, while medium- and micro-sized tumors displayed up to 5.02 and 152.28-fold size decrease compared to control-treated tumors, respectively. Eradication events occurred in 65 ± 2% of cases in micro-tumors only. In addition, Rad223 lost any therapeutic effect, also on micro-tumors, for distances bigger than 400 μm from the bone interface.

CONCLUSIONS

This model has the potential to be further developed to test additional bone targeting agents such as other radiopharmaceuticals or bisphosphonates.

Perspectives on Spinal Precautions in Patients Who Have Cancer and Spinal Metastasis

Bones are the third most common site for cancer metastases, and the axial skeleton is the most frequent skeletal location. In a postmortem study, bone metastases were reported in 70% of breast and prostate cancer patients. Bone metastases from breast, lung, prostate, thyroid, and kidney cancers account for 80% of all bone metastases. Bone lesions exist in 60% of newly diagnosed multiple myeloma patients. With increasing numbers of people who have survived cancer, many patients with cancer and axial skeletal bony metastases will be seen by physical and occupational therapists. Guidelines are lacking on how to perform physical examinations and provide exercise programs for these patients without compromising the diseased spine. In this article, we discuss the available evidence for similar spinal conditions, the biomechanics of spinal load, and changes associated with posture and weight load. We provide recommendations on how to assess a patient's strength, how to strengthen without compromising the diseased spine, and how to teach patients to use correct body mechanics during mobility and activities of daily living.