A 3-variable prognostic score (3-PS) for overall survival prediction in metastatic castration-resistant prostate cancer treated with 223Radium-dichloride

Predictive and Prognostic 18F-Fluorocholine PET/CT Radiomics Nomogram in Patients with Castration-Resistant Prostate Cancer with Bone Metastases Treated with 223Ra

PURPOSE

We aimed to develop a nomogram able to predict treatment failure, skeletal events, and overall survival (OS) in patients with castration-resistant prostate cancer with bone metastases (CRPC-BM) treated with Radium-223 dichloride (223Ra).

PATIENTS AND METHODS

Patients from the Castilla-La Mancha Spanish region were prospectively included in the ChoPET-Rad multicenter study from January 2015 to December 2022. Patients underwent baseline, interim, and end-of-treatment bone scintigraphy (BS) and 18F-Fluorocholine PET/CT (FCH PET/CT) scans, obtaining multiple imaging radiomics as well as clinical and biochemical variables during follow-up and studying their association with the previously defined end-points. Survival analysis was performed using the Kaplan-Meier method and Cox regression. Multivariate logistic and Cox regression models were calculated, and these models were depicted by means of nomograms.

RESULTS

Median progression-free survival (PFS) and OS were 4 and 14 months (mo), respectively. The variables that showed independent and significant association with therapeutic failure were baseline alkaline phosphatase (AP) levels (p = 0.022) and the characteristics of BM on the CT portion of PET/CT (p = 0.017). In the case of OS, the significant variables were therapeutic failure (p = 0.038), the number of lines received after 223Ra (p < 0.001), average SUVmax (p = 0.002), bone marrow infiltration in FCH PET/CT (p = 0.006), and interim FCH PET/CT response (p = 0.048). Final nomograms included these variables, showing good discrimination among the 100 patients included in our study. In the study of skeletal events, only OS showed a significant association in the multivariate analysis, resulting in an inconsistent nomogram design.

CONCLUSIONS

FCH PET/CT appears to be a good tool for evaluating patients eligible for treatment with 223Ra, as well as for their follow-up. Thus, findings derived from it, such as the morphological characteristics of BM in the CT, bone marrow infiltration, or the response to 223Ra in the interim study, have proven to be solid and useful variables in the creation of nomograms for predicting therapeutic failure and OS.

Prognostic biomarkers in the use of radium-223 in patients with metastatic castration-resistent prostate cancer

OBJECTIVES

This study aimed to establish basal biomarkers in patients with bone metastatic castration-resistant prostate cancer (mCRPC) treated with 223Ra to predict better overall survival (OS), and assess hematologic toxicity and treatment response.

MATERIALS AND METHODS

This was a retrospective multicenter study including 151 patients with mCRPC between 2013 and 2020. OS was assessed according to basal hemoglobin (Hb), prostate-specific antigen (PSA), and alkaline phosphatase (AP) values, the World Health Organization pain scale, the Eastern Cooperative Oncology Group (ECOG) performance status scale, the number of metastatic lesions on bone scintigraphy (BS), and the use of protective bone agents and the dose received. The grade of hematological toxicities was evaluated as well as treatment response based on changes in AP and pre- and post-treatment pain.

RESULTS

The median OS was 24 months (95% confidence interval 16.5-31). The OS in 70% of patients who received complete (5-6 doses) versus incomplete (1-4 doses) 223Ra treatment was 34.9 vs. 5.8 months, respectively, being longer in patients with lower PSA and AP values, Hb >13 g/dl, lesser bone metastasis on bone scan and with an ECOG 0-1. 52/151 patients (34%) died during follow-up. Pain reduced in nearly 70% of patients and 66% presented a reduction in AP values. Half of the patients presented mild and 5 % severe hematological adverse effects.

CONCLUSIONS

mCRPC patients treated with 223Ra with Hb values >13 g/mL, an ECOG 0-1, low AP values, PSA < 20 ng/mL and lesser bone metastasis on BS presented a better OS with an adequate safety profile.

The DASciS Software for BSI Calculation as a Valuable Prognostic Tool in mCRPC Treated with 223RaCl2: A Multicenter Italian Study

BACKGROUND/AIM

Radium-223 dichloride (²²³RaCl₂) represents a therapeutic option for metastatic castration-resistant prostate cancer (mCRPC) patients dealing with symptomatic bone metastases. The identification of baseline variables potentially affecting the life-prolonging role of ²²³RaCl₂ is still ongoing. Bone scan index (BSI) defines the total load of bone metastatic disease detected on a bone scan (BS) and is expressed as a percentage value of the whole bone mass. The aim of this multicenter study was to assess the impact of baseline BSI on overall survival (OS) in mCRPC patients treated with ²²³RaCl₂. For this purpose, the DASciS software developed by the Sapienza University of Rome for BSI calculation was shared between six Italian Nuclear Medicine Units.

METHODS

370 pre-treatment BS were analyzed through the DASciS software. Other clinical variables relevant to OS analysis were taken into account for the statistical analysis.

RESULTS

Of a total of 370 patients, 326 subjects had died at the time of our retrospective analysis. The median OS time from the first cycle of ²²³RaCl₂ to the date of death from any cause or last contact was 13 months (95%CI 12-14 months). The mean BSI value resulted in 2.98% ± 2.42. The center-adjusted univariate analysis showed that baseline BSI was significantly associated with OS as an independent risk factor (HR 1.137, 95%CI: 1.052-1.230, p = 0.001), meaning that patients with higher BSI values had worse OS. When adjusting for other measures on multivariate analysis, in addition to Gleason score and baseline values of Hb, tALP, and PSA, baseline BSI was confirmed to be a statistically significant parameter (HR 1.054, 95%CI: 1.040-1.068, p < 0.001).

CONCLUSIONS

Baseline BSI significantly predicts OS in mCRPC treated with ²²³RaCl₂. The DASciS software was revealed to be a valuable tool for BSI calculation, showing rapid processing time and requiring no more than a single demonstrative training for each participating center.

Real-world effectiveness, long-term safety and treatment pathway integration of radium-223 therapy in patients with metastatic castration-resistant prostate cancer

Radium-223 dichloride (223Ra) is an α-emitter approved for the treatment of metastatic castration-resistant prostate cancer (mCRPC) with bone metastases, but without visceral involvement. Despite being a life-prolonging therapy (LPT), 223Ra remains underutilized. A large body of real-world evidence (RWE) for 223Ra has been published in the decade since the pivotal phase 3 ALSYMPCA study, a period during which the treatment landscape has continued to evolve. How to optimize 223Ra use, including how to integrate it into the mCRPC management pathway amongst other current LPTs (i.e., with respect to timing and concurrent, layered, or sequential use), is therefore of considerable interest. RWE studies lack the conventional restraints of clinical trials and can therefore help to build an understanding of how treatments may be best used in routine practice. Here we review RWE studies investigating the efficacy and safety of 223Ra in mCRPC [including in sequence with the recently approved 177-Lutetium conjugated to the ligand prostate-specific membrane antigen (177Lu-PSMA)], as well as response marker development, imaging techniques, and current clinical practice recommendations.

Opportunistic skeletal muscle metrics as prognostic tools in metastatic castration-resistant prostate cancer patients candidates to receive Radium-223

OBJECTIVE

Androgen deprivation therapy alters body composition promoting a significant loss in skeletal muscle (SM) mass through inflammation and oxidative damage. We verified whether SM anthropometric composition and metabolism are associated with unfavourable overall survival (OS) in a retrospective cohort of metastatic castration-resistant prostate cancer (mCRPC) patients submitted to 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG PET/CT) imaging before receiving Radium-223.

PATIENTS AND METHODS

Low-dose CT were opportunistically analysed using a cross-sectional approach to calculate SM and adipose tissue areas at the third lumbar vertebra level. Moreover, a 3D computational method was used to extract psoas muscles to evaluate their volume, Hounsfield Units (HU) and FDG retention estimated by the standardized uptake value (SUV). Baseline established clinical, lab and imaging prognosticators were also recorded.

RESULTS

SM area predicted OS at univariate analysis. However, this capability was not additive to the power of mean HU and maximum SUV of psoas muscles volume. These factors were thus combined in the Attenuation Metabolic Index (AMI) whose power was tested in a novel uni- and multivariable model. While Prostate-Specific Antigen (PSA), Alkaline Phosphatase (ALP), Lactate Dehydrogenase and Hemoglobin, Metabolic Tumor Volume, Total Lesion Glycolysis and AMI were associated with long-term OS at the univariate analyses, only PSA, ALP and AMI resulted in independent prognosticator at the multivariate analysis.

CONCLUSION

The present data suggest that assessing individual 'patients' SM metrics through an opportunistic operator-independent computational analysis of FDG PET/CT imaging provides prognostic insights in mCRPC patients candidates to receive Radium-223.

Role of radium-223 discontinuation due to adverse events in castration-resistant prostate cancer patients. A retrospective monocentric analysis

Background:

Radium 223 (Ra-223) was approved for the treatment of metastatic castration resistant prostate cancer (mCRPC) patients with bone-only disease, following demonstration of significant improvement in overall survival (OS). To date, there are no validated prognostic factors useful in predicting outcome of mCRPC patients treated with Ra-223. Our retrospective study aims to evaluate the prognostic role of treatment discontinuation due to adverse events in mCRPC patients treated with Ra-223, and to identify which factors correlate with the toxicity onset.

Methods:

We performed a retrospective analysis of all consecutive mCRPC patients treated with Ra-223 from September 2013 to December 2019 at our institute. Patients were divided in 2 groups according to the reason of Ra-223 therapy discontinuation: toxicity versus other causes. Outcome measures were progression-free survival (PFS) and OS.

Results:

In the overall population (75 patients) median PFS and OS were 5.46 months and 11.15 months respectively. Patients who discontinued treatment due to toxicity had a lower median PFS (3.49 vs 5.89 months, HR: 1.88, 95% CI: 1.14-3.12, p = 0.014) and OS (8.59 vs 14.7 months HR: 3.33, 95% CI: 1.85-6.01, p < 0.001) than patients who discontinued therapy due to other causes. The risk of Ra-223 discontinuation due to toxicity correlates with the number of previous treatments ( p = 0.002), previous chemotherapy treatment ( p = 0.039), baseline LDH ( p = 0.012), Hb ( p = 0.021) and platelet-to-lymphocyte ratio ( p = 0.024).

Conclusions:

Discontinuation due to toxicity is associated with worse outcomes in mCRPC patients treated with Ra-223. To reduce the risk of developing toxicities that may compromise treatment efficacy, Ra-223 should be used early in mCRPC patients.

Prognostic Value of the BIO-Ra Score in Metastatic Castration-Resistant Prostate Cancer Patients Treated with Radium-223 after the European Medicines Agency Restricted Use: Secondary Investigations of the Multicentric BIO-Ra Study

The multicentric retrospective BIO-Ra study combined inflammatory indices from peripheral blood and clinical factors in a composite prognostic score for metastatic castration-resistant prostate cancer patients receiving Radium-223 (Ra-223). In the present study, we evaluated (i) the prognostic power of the BIO-Ra score in the framework of the restricted use of Ra-223 promoted by the European Medicines Agency in 2018; (ii) the treatment completion prediction of the BIO-Ra score. Four hundred ninety-four patients from the BIO-Ra cohort were divided into three risk classes according to the BIO-Ra score to predict the treatment completion rate (p < 0.001 among all the three groups). Patients receiving Ra-223 after restriction (89/494) were at later stages of the disease compared with the pre-restriction cohort (405/494), as a higher percentage of BIO-Ra high-risk classes (46.1% vs. 34.6%) and lower median Overall survival (12.4 vs. 23.7 months, p < 0.001) was observed. Despite this clinically relevant difference, BIO-Ra classes still predicted divergent treatment completion rates in the post-restriction subgroup (72%, 52.2%, and 46.3% of patients belonging to low-, intermediate-, and high-risk classes, respectively). Although the restricted use has increased patients at higher risk with unfavourable outcome after Ra-223 treatment, the BIO-Ra score maintains its prognostic value.

The prognostic power of inflammatory indices and clinical factors in metastatic castration-resistant prostate cancer patients treated with radium-223 (BIO-Ra study)

Purpose

To combine peripheral blood indices and clinical factors in a prognostic score for metastatic castration-resistant prostate cancer (mCRPC) patients treated with radium-223 dichloride ([²²³Ra]RaCl₂).

Patients and methods

Baseline neutrophil-to-lymphocyte ratio (NLR), derived NLR (donor), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), systemic inflammation index (SII), Eastern Cooperative Oncology Group performance status (ECOG PS), Gleason score (GS) group, number of bone metastases, prostate-specific antigen (PSA), alkaline phosphatase (ALP), line of therapy, previous chemotherapy, and the presence of lymphadenopathies were collected from seven Italian centers between 2013 and 2020. Lab and clinical data were assessed in correlation with the overall survival (OS). Inflammatory indices were then included separately in the multivariable analyses with the prognostic clinical factors. The model with the highest discriminative ability (c-index) was chosen to develop the BIO-Ra score.

Results

Five hundred and nineteen mCRPC patients (median OS: 19.9 months) were enrolled. Higher NLR, dNLR, PLR, and SII and lower LMR predicted worse OS (all with a p < 0.001). The multivariable model including NLR, ECOG PS, number of bone metastases, ALP, and PSA (c-index: 0.724) was chosen to develop the BIO-Ra score. Using the Schneeweiss scoring system, the BIO-Ra score identified three prognostic groups (36%, 27.3%, and 36.6% patients, respectively) with distinct median OS (31, 26.6, and 9.6 months, respectively; hazard ratio: 1.62, p = 0.008 for group 2 vs. 1 and 5.77, p < 0.001 for group 3 vs. 1).

Conclusions

The BIO-Ra score represents an easy and widely applicable tool for the prognostic stratification of mCRPC patients treated with [²²³Ra]RaCl₂ with no additional costs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05550-6.

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.

Clinicopathologic factors that influence prognosis and survival outcomes in men with metastatic castration-resistant prostate cancer treated with Radium-223

Background

In men with metastatic castration‐resistant prostate cancer (mCRPC) with primarily bone metastases, radium‐223 (²²³Ra) improves overall survival (OS). However, the selection of ²²³Ra is not guided by specific validated clinicopathologic factors, and thus outcomes are heterogeneous.

Patients and methods

This retrospective survival analysis was performed in men with mCRPC treated with ²²³Ra at our cancer center. Demographics and disease characteristics were collected. OS was calculated using the Kaplan–Meier method (log‐rank). The potential prognostic factors were determined using both univariable (UVA) and multivariable analysis (MVA) (Cox‐regression) methods.

Results

In total, 150 patients with a median age of 74 years (52–93) received ²²³Ra between May 2015 and July 2018, and 58% had 6–20 bone metastases. Ninety‐four (63%) patients received >4 ²²³Ra doses, and 56 (37%) received ≤4. The following pre‐treatment factors were analyzed (median [range]): eastern cooperative oncology group performance status (ECOG PS), (1 [0–3]); Albumin (ALB), (39 g/L [24–47]); alkaline phosphatase (ALP), (110 U/L [35–1633]); and prostate‐specific antigen (PSA), (49 µg/L [0.83–7238]). The median OS for all patients was 14.5 months (95% CI: 11.2–18). These factors were associated with poor survival outcomes in UVA and MVA: ALB <35 g/L, ALP >150 U/L, ECOG PS 2–3, and PSA >80 µg/L. By assigning one point for each of these factors, a prognostic model was developed, wherein three distinct risk groups were identified: good, 0–1 (n = 103); intermediate, 2 (n = 30); and poor risk, 3–4 points (n = 17). The median OS was 19.4, 10.0, and 3.1 months, respectively (p < 0.001).

Conclusions

Pre‐treatment ALB, ALP, ECOG, and PSA, were significantly correlated with OS and could guide treatment selection for men with mCRPC by identifying those who are most or least likely to benefit from ²²³Ra. Validation in an independent dataset is required prior to widespread clinical utilization.

A National Multicenter Study on overall survival in elderly metastatic castrate-resistant prostate cancer patients treated with Radium-223

BACKGROUND

Radium-223 prolongs overall survival (OS) and delays time to the first symptomatic skeletal events in patients with symptomatic metastatic castration-resistant prostate cancer (mCRPC). There is a lack of evidence on the safety and efficacy of Radium-223 treatment in the very elderly population.

AIMS

Aim of this multicentre study is to analyze mCRPC patients treated with Radium-223 in terms of OS and to assess whether there are differences between young and elderly, as well as to verify efficacy and safety in patients ≥ 75 years of age.

METHODS

430 mCRPC patients of six Italian Centres were analyzed in this multicenter retrospective study. At baseline and after each cycle were collected clinical and diagnostic patients' parameters. The whole cohort was divided into two groups based on the age of the patients (< 75 years old and ≥ 75 years old).

RESULTS

47% of the patients were < 75 years old and 53% were ≥ 75 years old. The primary outcome, OS, does not show significant differences between the two subgroups if other basal parameters are considered. Considering clinical covariates in univariate models (p < 0.05) several clinical aspects have an impact on OS, except for age (p = 0.072). Age continues to have no significant impact on the OS (p = 0.274) even in multivariate models in the two groups. The toxic effects are similar in the two groups.

CONCLUSIONS

Radium-223 prolongs survival in both younger and older patients at the same baseline condition and is a good option in the symptomatic mCRPC setting compared to other agents.

Prognostic Value of 18F-Choline PET/CT in Patients with Metastatic Castration-Resistant Prostate Cancer Treated with Radium-223

We aimed to investigate the role of positron emission computed tomography (PET/CT) with ¹⁸F-choline for predicting the outcome of metastatic castration-resistant prostate cancer (mCRPC) submitted to treatment with Radium-223 (²²³Ra-therapy). Clinical records of 20 mCRPC patients submitted to PET/CT with ¹⁸F-choline before ²²³Ra-therapy were retrospectively evaluated. The following PET-derived parameters were calculated: number of lesions, maximum and mean standardized uptake values (SUVmax, SUVmean), lean body mass corrected SUV peak (SULpeak), metabolic tumor volume (MATV), and total lesion activity (TLA). After ²²³Ra-therapy, all patients underwent regular follow-up until death. The predictive power of clinical and PET-derived parameters on overall survival (OS) was assessed by Kaplan–Meier analysis and the Cox proportional hazard method. All the patients showed ¹⁸F-choline-avid lesions at baseline PET/CT. Among the enrolled subjects, eleven (55%) completed all the six scheduled cycles of ²²³Ra-therapy; seven (35%) were responders according to imaging and biochemical parameters. Mean OS was 12.7 ± 1.4 months: by Kaplan–Meier analysis, number of lesions, PSA level and TLA were significantly correlated with OS. In multivariate Cox analysis, TLA remained the only significant predictor of survival (p = 0.003; hazard ratio = 7.6, 95% confidence interval = 1.9–29.5 months). ¹⁸F-choline PET may be useful for patients’ stratification before ²²³Ra-therapy. In particular, high metabolically active tumor burden (i.e., TLA) was predictive of poor outcome.

Overall survival in mCPRC patients treated with Radium-223 in association with bone health agents: a national multicenter study

PURPOSE

Radium-223 has demonstrated efficacy in improving overall survival (OS) and in delaying symptomatic skeletal-related events (SREs). Bone Health Agents (BHA), i.e. RANK ligand inhibitor (Denosumab) and bisphosphonate such as zoledronic acid, are indicated to prevent SREs without a clear survival benefit. SREs on patient health have a high impact and it is, therefore, important to consider the role of new therapies with BHA to better understand the involvement of combination therapy. The primary aim of this multicentric study is to assess OS in mCRPC patients treated with Radium-223 in combination with BHA.

MATERIALS AND METHODS

430 consecutive patients treated with Radium-223 alone or in combination with BHA, affected by mCRPC, from January 2015 to July 2019 in six Italian Nuclear Medicine Units, were included. Furthermore, data were collected at baseline, after every Radium-223 administration, and during follow-up, at 3 and 6 months and 1 year after the 6th cycle. Clinical data have been evaluated before starting treatment with Radium-223 and at the end of treatment and/or at progression. Patients who received target bone therapy with BHA before Radium-223 treatment together with patients who did not receive this therapy at all (NO BHA GROUP), were compared to patients treated with concomitant Radium-223 and BHA (BHA GROUP).

RESULTS

In univariate models (p < .05) several clinical aspects have an impact on OS: concomitant BHA (p = .018), BMI (p .001), ECOG PS (p = .000), Baseline Hb (p = .000), Baseline PSA (p = .000), Baseline tALP (p = .000), Baseline LDH (p = .000), and Baseline neutrophils (p = .009). Baseline Hb, Baseline tALP, and Baseline LDH have been confirmed as statistically significant parameters in multivariate models. Indeed, concomitant BHA has not a significant impact on OS (p = .244) in multivariate models.

CONCLUSIONS

At univariate analysis, our data showed that NO BHA GROUP and BHA GROUP differ in OS by 7 months (95%CI: (1-16.4), p = .02). This is not confirmed at multivariate analysis where after adjusting for other baseline factors, BHA is not significant anymore. This is clearly explained as bias by indication: patients with the same levels of tALP, Hb, and LDH receiving or not receiving BHA are expected to have a similar survival. Our results support and confirm the role of Radium-223 therapy on OS and, furthermore, appear to confirm that BHA treatment has not a survival benefit.

The Prognostic Role of Baseline Metabolic Tumor Burden and Systemic Inflammation Biomarkers in Metastatic Castration-Resistant Prostate Cancer Patients Treated with Radium-223: A Proof of Concept Study

Over the last years has emerged the urgent need for the identification of reliable prognostic biomarkers able to potentially identify metastatic castration-resistant prostate cancer (mCRPC) patients most likely to benefit from Radium-223 (Ra-223) since baseline. In the present monocentric retrospective study, we analyzed the prognostic power of systemic inflammation biomarkers and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET)-derived parameters and their potential interplay in this clinical setting. The following baseline laboratory parameters were collected in 59 mCRPC patients treated with Ra-223: neutrophil-to-lymphocyte ratio (NLR), derived NLR (dNLR), lymphocyte-to-monocyte ratio (LMR), platelets-to-lymphocyte ratio (PLR), and systemic inflammation index (SII), while maximum Standardized Uptake Value, Metabolic Tumor Volume (MTV), and Total Lesion Glycolysis (TLG) were calculated in the 48 of them submitted to baseline FDG-PET. At the univariate analysis, NLR, dNLR, MTV, and TLG were able to predict the overall survival (OS). However, only NLR and MTV were independent predictors of OS at the multivariate analysis. Additionally, the occurrence of both increased NLR and MTV at baseline identified mCRPC patients at higher risk for lower long-term survival after treatment with Ra-223. In conclusion, the degree of systemic inflammation, the quantification of the metabolically active tumor burden and their combination might represent potentially valuable tools for identifying mCRPC patients who are most likely to benefit from Ra-223. However, further studies are needed to reproduce these findings in larger settings.

Radium-223 in mCPRC patients: a large real-life Italian multicenter study

BACKGROUND

Radium-223 is a targeted alpha-particles therapy approved for the treatment of mCRPC patients with symptomatic bone metastases. To our knowledge we account for the largest cohort of mCRPC patients subjected to Radium-223 treatment in our country. We aim to describe in a real-life setting the largest cohort of mCRPC patients treated with Radium-223 ever taken into consideration.

METHODS

Four hundred and thirty consecutive mCRPC patients were enrolled. Clinical data have been collected at baseline and at the end of the Radium-223 treatment. Furthermore, the overall survival(OS) of our population has been provided.

RESULTS

One hundred fifty-seven patients (36.5%) were still alive at the time of data analysis. A mean number of 4.95±1.6 cycles of Radium-223 was reached by our cohort. 265 patients (61.6%) completed the whole six cycles regimen. The mean follow-up period from the first cycle of Radium-223 to the date of the analysis was 12.7 months. The analysis of patients Annual Incidence Rate (AIR) in relation to the number of Radium-223 cycles received depicting a clear advantage for those patients who completed the whole six administrations planned, with an AIR (AIR=0.32) of much lesser value compared to those that have performed five cycles (AIR =0.98). 165 patients (38.4%) dropped out of treatment for death or disease progression.

CONCLUSIONS

This study offers a cross-section of the clinical performance of Radium-223 treatment in a real-world context, confirming on a large scale the effectiveness of Radium-223 in improving the OS and quality of life, along with the preservation of an excellent safety profile.

Validation of the 3-variable prognostic score (3-PS) in mCRPC patients treated with 223Radium-dichloride: a national multicenter study

Objective

Radium-223 (²²³Ra) has been approved for treatment in patients with metastatic castration-resistant prostatic cancer (mCRPC) and bone metastasis. This α-emitting radionuclide has a beneficial effect on pain and is also capable to increase overall survival (OS). Several studies evaluated the prognostic value of different biomarkers at baseline, such as serum values, imaging parameters or pain. To date, however, clinicians lack a validated and simple system to assess which patients will most likely benefit from ²²³Ra treatment. The 3-variable prognostic score (3-PS), proposed in a single-center study in 2017 classifies patients in five prognostic groups with a specific OS. This study aims to validate the 3-PS in a larger multicenter population.

Methods

Four hundred and thirty mCRPC patients treated with ²²³Ra from six different centers were analyzed. The 3-PS score consists of the collection of baseline hemoglobin, prostatic specific antigen and Eastern cooperative oncology group performance status and was initially applied to the whole population (total group). The score was then validated on the 338 patient’s subgroup (clean group) obtained by subtracting the 92 patients enrolled for the original study of the 3-PS score. This purified group served as further validation evidence.

Results

Statistical analysis showed that the 3-PS score was valid on the total group as well as in the clean group as the AUC estimated (0.74) falls within the CI of the AUC calculated on the validation sample (95% CI 0.66–0.82).

Conclusion

This study confirms the validity of the 3-PS score for mCRPC patients. This score is simple, noninvasive and affordable and can be easily used to select patients that will most probably complete ²²³Ra treatment. In addition, this tool provides an exact estimate of life expectancy in terms of OS.

Clinical aspects of mCRPC management in patients treated with radium-223

Bone is the most common site of metastasis in metastatic castration-resistant prostate cancer (mCRPC), which is associated with pain and skeletal events. Radium-223 dichloride (Xofigo) is an alpha-emitting radioactive isotope that can specifically target bone lesions. Herein, we report the results of a retrospective analysis that documents our experience in the use of radium-223. Data from 63 patients (pts) with mCRPC who underwent radium-223 treatment from December 2015 to September 2017 were collected. Radium-223 (55 kBq/kg) was administered every 4 weeks for up to 6 cycles. The primary endpoint was OS. Radium-223 was administered as first line therapy in 11 pts, as second line in 19 pts, as third line in 16 pts and in successive lines in 17 pts; 42 pts out of 63 (67%) completed all six cycles. Within one month after the end of 6 cycles of radium-223, 15 pts out of 42 (35.7%) had achieved PR, 11 pts out of 42 (26.2%) had SD and 14 pts out of 42 (33.3%) had PD. Levels of pain decreased with progressive cycles of radium-223. After a minimum follow-up of 2 months and a maximum of 43 months, median OS was 15 months and median PFS was 8 months. The most frequent radium-223 related toxicity was low grade haematologic toxicity, predominantly G1-G2, that occurred halfway through treatment in about 75% of pts. The favourable results reported herein confirm that radium-223 can be considered well tolerated and effective in mCRPC, and is associated with significant decreases in pain.

Overall survival prediction in metastatic castration-resistant prostate cancer treated with radium-223

Objective

Radium-223(223Ra) is indicated for patients (p) with metastatic castration resistant prostate cancer (mCRCP).

Objectives

The aim of this study was to evaluate the role of baseline clinical variables associated with overall survival (OS) and toxicity of 223Ra. Its purpose was to identify the factors that can predict a better response to treatment and provide information regarding the most appropriate time for the application of 223Ra.

Materials and Methods

Prospective study in 40p with mCRPC treated with 223Ra. End points were OS, progression-free survival and time to progression. The follow-up parameters were: doses received, hemoglobin (Hb), absolute neutrophil count (ANC), platelet count (PC), prostate specific antigen (PSA), alkaline phosphatase (ALP), Visual Analogue Scale for pain, Eastern Cooperative Oncology Group (ECOG) and WHO’s Cancer Pain Ladder. The use of other treatments was also evaluated.

Results

Median OS was 17.1 months(mo) (CI95%6.5-27.7); 26/40p received complete treatment of 223Ra, without reaching a median OS and 14p received incomplete treatment with a median OS 13.6mo(CI95%1.6-25.6). Median follow-up was 11.2mo (range:1.3-45.2). The univariate analysis showed that factors as VAS, ECOG, Hb and ALP values were independently associated with OS. First line treatment with 223Ra was started in 11/40p, while 19p had been heavily pre-treated and 13p received concomitant treatment.

Conclusions

223Ra therapy require an adequate selection of patients to obtain the greatest clinical benefit. Low basal Hb, hight basal ALP, bone marrow involvement and an altered ECOG were the main factors that decreased OS in our patients. 223Ra should be considered relatively early in the course of treatment.

Role of Baseline and Post-Therapy 18F-FDG PET in the Prognostic Stratification of Metastatic Castration-Resistant Prostate Cancer (mCRPC) Patients Treated with Radium-223

Radium-223 dichloride (Ra223) represents the unique bone-directed treatment option that shows an improvement in overall survival (OS) in metastatic castrate resistant prostate cancer (mCRPC). However, there is an urgent need for the identification of reliable biomarkers to non-invasively determine its efficacy (possibly improving patients’ selection or identifying responders’ after therapy completion). 18F-Fluorodeoxyglucose (FDG)-avidity is low in naïve prostate cancer, but it is enhanced in advanced and chemotherapy-refractory mCRPC, providing prognostic insights. Moreover, this tool showed high potential for the evaluation of response in cancer patients with bone involvement. For these reasons, FDG Positron Emission Tomography (FDG-PET) might represent an effective tool that is able to provide prognostic stratification (improving patients selection) at baseline and assessing the treatment response to Ra223. We conducted a retrospective analysis of 28 mCRPC patients that were treated with Ra223 and submitted to bone scan and FDG-PET/CT for prognostic purposes at baseline and within two months after therapy completion. The following parameters were measured: number of bone lesions at bone scan, SUVmax of the hottest bone lesion, metabolic tumor volume (MTV), and total lesion glycolysis (TLG). In patients who underwent post-therapy 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET/CT), (20/28), PET Response Criteria in Solid Tumors (PERCIST), and European Organization for Research and Treatment of Cancer (EORTC) criteria were applied to evaluate the metabolic treatment response. The difference between end of therapy and baseline values was also calculated for Metabolic Tumor Volume (MTV), TLG, prostate-specific antigen (PSA), alkaline phosphatase (AP), and lactate dehydrogenase (LDH) (termed deltaMTV, deltaTLG, deltaPSA, deltaAP and deltaLDH, respectively). Predictive power of baseline and post-therapy PET- and biochemical-derived parameters on OS were assessed by Kaplan–Meier, univariate and multivariate analyses. At baseline, PSA, LDH, and MTV significantly predicted OS. However, MTV (but not PSA nor LDH) was able to identify a subgroup of patients with worse prognosis, even after adjusting for the number of lesions at bone scan (which, in turn, was not an independent predictor of OS). After therapy, PERCIST criteria were able to capture the response to Ra223 by demonstrating longer OS in patients with partial metabolic response. Moreover, the biochemical parameters were outperformed by PERCIST in the post-treatment setting, as their variation after therapy was not informative on long term OS. The present study supports the role of FDG-PET as a tool for patient’s selection and response assessment in mCRPC patients undergoing Ra223 administration.

Scintigraphic load of bone disease evaluated by DASciS software as a survival predictor in metastatic castration-resistant prostate cancer patients candidates to 223RaCl treatment

Background

Aim of our study was to assess the load of bone disease at starting and during Ra-223 treatment as an overall survival (OS) predictor in metastatic castration-resistant prostate cancer (mCRPC) patients. Bone scan index (BSI) is defined as the percentage of total amount of bone metastasis on whole-body scintigraphic images. We present a specific software (DASciS) developed by an engineering team of “Sapienza” University of Rome for BSI calculation.

Patients and methods

127 mCRPC patients bone scan images were processed with DASciS software, and BSI was tested as OS predictor.

Results

546 bone scans were analyzed revealing that the extension of disease is a predictor of OS (0–3% = 28 months of median survival (MoMS]; 3%–5% = 11 MoMS, > 5% = 5 MoMS). BSI has been analyzed as a single parameter for OS, determining an 88% AUC. Moreover, the composition between the BSI and the 3-PS (3-variable prognostic score) determines a remarkable improvement of the AUC (91%), defining these two parameters as the best OS predictors.

Conclusions

This study suggests that OS is inversely correlated with the load of bone disease in mCRPC Ra-223-treated subjects. DASciS software appears a promising tool in identifying mCRPC patients that more likely take advantage from Ra-223 treatment. BSI is proposed as a predictive variable for OS and included to a multidimensional clinical evaluation permits to approach the patients’ enrollment in a rational way, allowing to enhance the treatment effectiveness together with cost optimization.

Circulating tumor cells and γH2AX as biomarkers for responsiveness to radium-223 in advanced prostate cancer patients

Aim

Radium-223 improves overall survival in patients with metastatic castration-resistant prostate cancer to the bone. Radium-223 causes double-strand DNA breaks and produces γH2AX, a potential biomarker for response. We examined the feasibility of tracking γH2AX positivity and numeration in circulating tumor cells.

Patients & methods

Ten patients with biopsy-confirmed symptomatic M1b castration-resistant prostate cancer received radium-223 as standard of care and were assessed for γH2AX level changes following doses 1, 3 and 6.

Results

Trend tests confirmed that patients with ≥50% increase in circulating tumor cells positive for γH2AX postradium-223 therapy had a lower risk of death (p = 0.035).

Conclusion

Regular interval measurements of γH2AX are feasible. The potential correlation between γH2AX changes and overall survival warrants further investigation.

Primary Radical Prostatectomy or Ablative Radiotherapy as Protective Factors for Patients With mCRPC Treated With Radium-223 Dichloride: An Italian Multicenter Study

BACKGROUND

We investigated, in a real-life setting, the prognostic relevance of previous primary treatment (radical prostatectomy [RP] or external beam radiotherapy [EBRT]) on overall survival for patients with metastatic castration-resistant prostate cancer (mCRPC) treated with radium-223 (²²³Ra).

MATERIALS AND METHODS

In the present multicenter retrospective study, we enrolled 275 consecutive patients. The demographic and clinical data and mCRPC characteristics were recorded and evaluated at baseline and at the end of treatment or progression. ²²³Ra was administered according to the current label authorization until disease progression or unacceptable toxicity. We divided the whole cohort into 2 groups: those who had undergone primary radical prostatectomy or ablative radiotherapy (RP/EBRT) and those who had not received previous primary treatment (NO).

RESULTS

Of the 275 patients, 128 (46.5%) were alive and undergoing monitoring at the last follow-up examination, 103 (37.4%) had stopped treatment because of disease progression or the onset of comorbidities, and 147 (53.5%) had died during the study period. Of the 275 patients, 132 were in the RP/EBRT group (48%), of whom 93 had undergone RP and 76 had undergone ablative EBRT, and 143 patients were in the NO group (52%). The data showed a clear advantage for the patients in the RP/EBRT group compared with those in the NO group, with an estimated median survival of 18 versus 11 months, respectively (P < .001). The results from the multivariate analysis corroborated this trend, with a hazard ratio of 0.7 (P = .0443), confirming the better outcome for the RP/EBRT group.

CONCLUSIONS

Previous radical treatment provides a protective role for patients with mCRPC undergoing ²²³Ra treatment.

Analysis of Unusual Adverse Effects After Radium-223 Dichloride Administration

BACKGROUND

To our knowledge, no previous study or literature review has been performed about the effects of the extravasation of therapeutic radiopharmaceutical agents and its potential consequences, especially regarding alpha-particle emitting radiopharmaceuticals.

METHODS

Even if Radium-223 dichloride is known to be a relatively safe drug to manage, despite the correctness of the procedures applied , unexpected delayed adverse effects can occur. In our vast experience, we rarely observed lymphedema, even after some time, at the site of administration.

RESULTS

Management of lymphedema caused by radiopharmaceuticals administration has been addressed through clinical examples. The sudden intervention allowed a fast remission of the signs and symptoms complained by patients treated with Radium-223 dichloride.

CONCLUSION

The management of adverse effects after radiopharmaceuticals administration as in case of lymphedema onset, is extremely simple. These data confirm the safety of Radium-223 treatment.

Key Role of Obesity in Genitourinary Tumors with Emphasis on Urothelial and Prostate Cancers

Background: In human populations, a certain amount of data correlate obesity/body mass index (BMI) with urothelial cancer (UC) and prostate cancer (PCa) occurrence, however this is not fully elucidated at all stages of disease. In an attempt to shed light on uncertain areas in such field, in the present review we illustrate the main molecular mechanisms linking obesity and cancer, focusing on the correlation between obesity and tumor risk, disease progression and response to chemo- and immunotherapy in patients with UC and the predictive/prognostic role of obesity in PCa patients treated with the currently available therapeutic approaches. Methods: We did a large-scale literature search on existing scientific websites focusing on keywords "obesity", "body mass index (BMI)", "urothelial cancer", "prostate cancer", "docetaxel", "cabazitaxel", "abiraterone acetate", "enzalutamide", and "radium223". Results: Many adipocytes-induced molecules support tumor proliferation through activation of various cellular pathways. The available evidence in the postoperative setting do the role of BMI in oncological outcomes prediction still not completely clear. Likewise, in metastatic UC patients controversial results link the role of obesity/BMI with clinical outcomes of tumor response to chemotherapy. Adipose stromal cells recruitment, induced by PCa cells, from white adipose tissue to the tumor sites inducing cell invasiveness was associated with poor survival. Conflicting data, although more oriented towards a better survival outcome, resulted in obese patients treated with docetaxel. In PCa cell-lines a certain cabazitaxel chemo resistance adipose stromal cells (ASC)-mediated was demonstrated. In metastatic castration-resistant PCa patients with high BMI (>25 kg/m2) receiving abiraterone acetate there were significant worse survival outcomes, while in enzalutamide patients BMI did not affect survival outcome. In radium 223 patients higher BMI significantly correlated with favorable overall survival. Conclusions: The main focus of this review was to understand the interplay between obesity/BMI and UC/PCa. Several pathogenic cellular pathways exploring the issue are discussed, opening the way to challenging tailored treatments on the basis of BMI. Improving the knowledge of molecular connections between obesity and UC and PCa could favor the development of new therapies likely reducing chemo- and immunotherapy drug resistance.

No evidence of association between psychological distress and pain relief in patients with bone metastases from castration-resistant prostate cancer treated with 223Radium

OBJECTIVE

Painful bone metastases cause reduced quality of life (QoL) in patients with castration-resistant prostate cancer (CRPC). Alpha-emitter 223Radium is associated with a clear survival benefit and significant bone pain palliation in CRPC patients with symptomatic bone metastases. The aim of this study was to evaluate the association between pain relief and psychological distress during the time course of therapy in patients treated with 223Radium.

METHODS

A total of 63 patients with mCRPC undergoing 223Radium treatment in our Nuclear Medicine Unit, carefully instructed on the possibility of improving the pain and increasing the survival by the treatment, were retrospectively evaluated. Pain response during treatment was assessed with the Brief Pain Inventory Numeric Rating Scale. Psychological distress was evaluated through the analysis of specific items from EORTC QoL questionnaires C30 and BM22, submitted to patients at baseline and after each 223Radium cycle.

RESULTS

Pain intensity showed a significant decrease after first 223Radium administration (-1.03 points, p = 0.0032), with a subsequent stability through the course of treatment (-1.30 points, p = <0.001). Psychological status did not show significant variations during 223Radium treatment, and no association was found between psychological status and pain relief in our population.

CONCLUSIONS

In our experience, bone pain palliation provided by 223Radium do not correlate with an improved psychological status in patients with advanced PC. This observation emphasises the role of the psychological aspect in the evaluation of the QoL and the necessity of a multidisciplinary approach in which the emotional aspect of the patient is carefully evaluated.

Reversibility of castration resistance status after Radium-223 dichloride treatment: clinical evidence and review of the literature

In the history of prostate cancer, some of the patients progressed to castration-resistant prostate cancer (CRPC) stage and, although new drugs and treatment protocols have been introduced, CRPC presents poor prognosis. This review is focused on biological mechanisms, underlying CRPC described in scientific literature in order to explain the reversion of resistance to castration. We present the case of a 73-year-old man, affected by bone metastatic CRPC, early treated with Radium-223 with a complete response. After 15 months from Radium-223 treatment, prostate-specific antigen increased with radiological progression. Androgen deprivation therapy was again performed and was effective, despite previous CRPC condition and no known mechanisms that may explain the reversion of this condition. Therefore, to our knowledge, he is the unique described case of the reversion of resistance to castration. Nevertheless, promising aspects may be lack of intrametastatic production of androgen or the suppression of bypass androgen receptor signaling pathways. Furthermore, the cytotoxic action of Radium-223 on cancer stem cell (CSC), due to surrounding clones with high-bone turnover, or the immune response that underlying the abscopal effect, may also modulate the reversion of CRPC after Radium-223. If confirmed by multicenter trials, the reversion of CRPC may impact on the management of prostate cancer.

Patient Selection for Radium-223 Therapy in Patients With Bone Metastatic Castration-Resistant Prostate Cancer: New Recommendations and Future Perspectives

Radium-223 therapy was registered in 2013 as a new life-prolonging therapeutic option for patients with symptomatic bone metastatic castration-resistant prostate cancer after the phase 3 ALSYMPCA study. Postregistration reports on the use of radium-223 in real-world populations demonstrate that appropriate selection of patients for radium-223 therapy is challenging. While primarily retrospective and post hoc studies identified prognostic variables associated with overall survival, validated predictive biomarkers are still lacking. Important pretherapeutic prognostic variables include the number of prior therapies, baseline Eastern Cooperative Oncology Group performance status, baseline extent of bone metastatic disease, and baseline alkaline phosphatase, prostate-specific antigen, and lactate dehydrogenase levels. We reviewed the currently available literature to provide recommendations on patient selection for radium-223 therapy in patients with bone metastatic castration-resistant prostate cancer. In addition, the recent evidence from the report of the European Medicines Agency's Pharmacovigilance Risk Assessment Committee regarding the restricted use of radium-223 after interim data analysis of the ERA-223 trial has been incorporated into our recommendations. Future perspectives are also discussed, including radium-223 re-treatment, the use of concomitant therapies, and the implementation of pretherapeutic molecular analysis for treatment stratification.