Multiple rechallenges for castration-resistant prostate cancer patients responding to first-line docetaxel: assessment of clinical outcomes and predictive factors

Significant reduction in burden of metastatic disease by intermittent docetaxel therapy in a patient with castration-resistant prostate cancer

Intermittent docetaxel therapy (IDT) is rarely used nowadays as a treatment option for men with metastatic castration-resistant prostate cancer (mCRPC) because of the widespread availability of androgen receptor axis-targeted therapy, which is less toxic. Therefore, there is limited information available on whether IDT has a clinical benefit in the treatment of men with mCRPC. This report describes the case of a 66-year-old man with a diagnosis of cT2N1M0 prostate cancer who underwent neoadjuvant combined androgen blockade and whole-pelvis radiation therapy. However, the tumor had progressed to mCRPC with metastasis to the bladder and a left pelvic lymph node within 2 years. Docetaxel had been administered as first-line chemotherapy, and the patient achieved a complete response in terms of the bladder metastasis. Docetaxel was stopped after 15 cycles. When a durable response had been maintained for more than 2 years, during which only androgen deprivation therapy was administered, the patient was switched to observation only. However, his prostate-specific antigen level gradually increased. Abiraterone was started as second-line therapy, during which there was a rapid increase in the PSA level. Computed tomography revealed further enlargement of the left pelvic lymph node, bladder metastasis, metastasis to the left common iliac lymph nodes, and several disseminated nodules around the bladder. Docetaxel was reintroduced as IDT for third-line therapy, and a complete response was achieved for all metastases, with the exception of the metastasis in the left pelvic lymph node. Thus far, the patient has survived for more than 7 years after starting docetaxel as first-line therapy for mCRPC. IDT is potentially useful in a subgroup of patients with mCRPC and could achieve long-term survival. Comprehensive genomic profiling may help physicians to select patients with mCRPC who are more likely to benefit from docetaxel than other systemic therapy.

UnCHAARTED territory: The role of docetaxel rechallenge following chemohormonal therapy for metastatic castration-sensitive prostate cancer

OBJECTIVE

To assess the effectiveness of docetaxel rechallenge (DR) for metastatic castration-resistant prostate cancer (mCRPC) following chemohormonal therapy for metastatic castrate-sensitive prostate cancer (mCSPC). Additionally, we sought to define clinical factors predicting treatment response.

PATIENTS AND METHODS

Retrospective analysis of men treated with docetaxel for mCSPC and then rechallenged in the mCRPC setting from four cancer centers in Ontario, Canada. Prostate specific antigen (PSA) response, progression-free survival (PFS), and overall survival (OS) following DR were evaluated.

RESULTS

Fifty five patients were identified between 2015 and 2020. Prior to DR, 94.5% of patients received androgen-receptor axis targeted therapy, 20% received radium-223, and 1.8% received cabazitaxel. Among 54 evaluable patients, 27.8% had a PSA decline ≥50%. Median PFS was 4.1 months (95% CI, 2.1-4.8) and median OS from androgen deprivation therapy initiation was 38.3 months (95% CI, 32.9-41.0). A Gleason Score of ≥8 was an independent predictor of prolonged PFS (HR 0.32, 95% CI, 0.12-0.81; P=0.02).

CONCLUSIONS

DR following chemohormonal therapy for mCSPC produced a meaningful PSA response in approximately one-quarter of patients, with relatively short PFS. The impact of Gleason Score on docetaxel response warrants further investigation.

Beyond cabazitaxel: Late line treatments in metastatic castration resistant prostate cancer: A retrospective multicentre analysis

AIMS

Multiple life-prolonging therapies are available for metastatic castration-resistant prostate cancer (mCRPC). However, the optimal treatment strategy following progression through standard treatment with docetaxel, androgen receptor signaling inhibitor (ARSI) and cabazitaxel, remains unclear. We aimed to describe treatment patterns in men with mCRPC following progression on standard treatments and determine whether subsequent treatment choice impacts overall survival.

METHODS

Clinicopathologic and treatment data were extracted from the electronic CRPC Australian Database (ePAD) for patients who had received docetaxel, ARSIs and cabazitaxel in any order. Data were analyzed to compare groups that did versus did not receive subsequent systemic therapy. Treatment sequences, median duration of treatment, and median overall survival (mOS) were reported for each treatment group.

RESULTS

Ninety-eight eligible patients were identified, with 51 receiving subsequent systemic therapy. Those who received further treatment were younger (68 vs. 71 years, p < .01) but did not have any other differences in clinicopathologic features compared to those who received no further treatment. Patients who received upfront docetaxel were more likely to proceed to subsequent treatment (p = .02). Subsequent systemic therapies varied, the most common being carboplatin-based regimens (n = 13, 25.5%) and many patients were rechallenged with ARSI (n = 10, 19.6%) or docetaxel (n = 6, 11.8%). There was no difference in mOS according to subsequent systemic therapy (p = .09).

CONCLUSION

This retrospective multicenter analysis demonstrates the variation in treatment sequences used for mCRPC in the real-world setting. In the absence of high quality, prospective evidence, our results suggest that subsequent treatment choice does not influence survival outcomes and the optimal choice is guided by individual patient and disease-related factors.

Multiple Docetaxel Retreatments Without Prednisone for Metastatic Castration-Resistant Prostate Cancer in the Docetaxel-Only Era: Effects on PSA Kinetics and Survival

Introduction

This study aimed to assess the effects of multiple docetaxel (DOC) treatments on prostate-specific antigen (PSA) kinetics and survival among patients with metastatic castration-resistant prostate cancer (mCRPC) who were sensitive to first-line DOC and received no other life-prolonging agents. To eliminate the effect of cortisone on serum PSA, only patients who were treated without prednisone were included.

Methods

This IRB-approved retrospective study evaluated 52 patients with mCRPC who were retreated using DOC after first-line DOC (without prednisone in both cases), based on a PSA response of > 50% and no radiographic progression. Twenty-three PSA-based factors, including static and kinetic PSA measures, were evaluate for their ability to predict overall survival (OS)

Results

The patients received 688 cycles of DOC in 143 series, including 91 courses of retreatments (1 cycle: 28 patients, 2 cycles: 14 patients, 3 cycles: 8 patients, 4 cycles: 1 patient, and 7 cycles: 1 patient). The median overall number of cycles per patient was 12 (range: 7–31). The median durations of the first, second, and third holidays were 18 weeks (6–60 weeks), 16 weeks (3–44 weeks), and 17 weeks (8–51 weeks), respectively. The median OSs were 22 months (10.5–70 months) after the first DOC treatment and 14 months (3–65 months) after the second DOC treatment. The > 50% PSA decline rate was 48% after retreatment. Short treatment holidays (< 3 months) were associated with shortened OS (p = 0.01). In the multivariate analysis, a 25% PSA increase over the nadir was the strongest predictor of survival (HR: 3.20, 95% CI: 1.47–6.99, p = 0.003).

Conclusions

DOC retreatment without prednisone had anti-tumor activity in a considerable proportion of mCRPC cases that were initially sensitive to first-line DOC. A 25% PSA increase over the nadir might predict acquired DOC resistance.

2020 Korean guidelines for the management of metastatic prostate cancer

In 2017, Korean Society of Medical Oncology (KSMO) published the Korean management guideline of metastatic prostate cancer. This paper is the 2nd edition of the Korean management guideline of metastatic prostate cancer. We updated recent many changes of management in metastatic prostate cancer in this 2nd edition guideline. The present guideline consists of the three categories: management of metastatic hormone sensitive prostate cancer; management of metastatic castration resistant prostate cancer; and clinical consideration for treating patients with metastatic prostate cancer. In category 1 and 2, levels of evidence (LEs) have been mentioned according to the general principles of evidence-based medicine. And grades of recommendation (GR) was taken into account the quality of evidence, the balance between desirable and undesirable effects, the values and preferences, and the use of resources and GR were divided into strong recommendations (SR) and weak recommendations (WR). A total of 16 key questions are selected. And we proposed recommendations and described key evidence for each recommendation. The treatment landscape of metastatic prostate cancer is changing very rapid and many trials are ongoing. To verify the results of the future trials is necessary and should be applied to the treatment for metastatic prostate cancer patients in the clinical practice. Especially, many prostate cancer patients are old age, have multiple underlying medical comorbidities, clinicians should be aware of the significance of medical management as well as clinical efficacy of systemic treatment.

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.

Maintenance Long-Term Multiple Cycles Treatment with Docetaxel in Metastatic Castration-Resistant Prostate Cancer: A Report of Three Cases

Prostate cancer (PCa) is one of the most common types of malignancy, most patients with PCa will eventually progress to metastatic castration-resistant prostate cancer (mCRPC), which has a poor prognosis. Since 2004, chemotherapy has been approved by the FDA as the first-line treatment for mCRPC, and docetaxel-based regimens have been shown to improve both the patients’ symptoms and overall survival (OS). 10 cycles of docetaxel therapy are usually given to patients with mCPRC, but there is still no consensus on the optimal number of treatment cycles. Here, we present three cases of mCRPC patients that received maintenance long-term multiple-cycles docetaxel treatment. We believe that this new treatment strategy may benefit carefully selected mCRPC patients and provide several key advantages such as maximum exposure to drugs, improvements in drug efficacy, and reduce the risk of developing drug resistance.

PSA Kinetics as Prognostic Markers of Overall Survival in Patients with Metastatic Castration-Resistant Prostate Cancer Treated with Abiraterone Acetate

Background

Abiraterone acetate (AA) is widely used in the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC). However, a significant percentage of patients will still progress, highlighting the need to identify patients more likely to benefit from AA. Parameters linked to prostate-specific antigen (PSA) kinetics are promising prognostic markers. We have examined clinical and PSA-related factors potentially associated with overall survival (OS) in patients treated with AA.

Methods

Between 2011 and 2014, 104 patients with mCRPC treated with AA after progression to docetaxel at centers of the Catalan Institute of Oncology were included in this retrospective study. Patients were assessed monthly. Baseline characteristics and variables related to PSA kinetics were included in univariate and multivariate analyses of OS.

Results

Median OS was 16.4 months (range 12.4-20.6) for all patients. The univariate analysis identified the following baseline characteristics as significantly associated with OS: ECOG PS, location of metastases, time between starting androgen deprivation therapy and starting AA, time between stopping docetaxel treatment and starting AA, neutrophil-lymphocyte ratio (NLR), alkaline phosphatase levels, and PSA levels. Factors related to PSA kinetics associated with longer OS were PSA response >50%, early PSA response (>30% decline at four weeks), PSA decline >50% at week 12, PSA nadir <2.4ng/mL, time to PSA nadir >140 days, the combination of PSA nadir and time to PSA nadir, and low end-of-treatment PSA levels. The multivariate analysis identified ECOG PS (HR 37.46; p<0.001), NLR (HR 3.7; p<0.001), early PSA response (HR 1.22; p=0.002), and time to PSA nadir (HR 0.39; p=0.002) as independent prognostic markers.

Conclusion

Our results indicate an association between PSA kinetics, especially early PSA response, and outcome to AA after progression to docetaxel. Taken together with other factors, lack of an early PSA response could identify patients who are unlikely to benefit from AA and who could be closely monitored with a view to offering alternative therapies.

Docetaxel Rechallenge in Patients with Metastatic Prostate Cancer: A Comprehensive Review

BACKGROUND

Recent years have witnessed a huge shift in the management and prognosis of metastatic prostate cancer with the advent of new-generation anti-hormonal treatments. Docetaxel, which was initially approved in the castrate-resistant prostate cancer setting, has been approved in the earlier course of the disease as it is still castrate sensitive.

SUMMARY

Apart from cabazitaxel and in the absence of other effective chemotherapies, docetaxel rechallenge (DR) in patients with proved sensitivity to docetaxel in the earlier stage of the disease remains a possible option. Unfortunately, the pivotal trials rarely reported on the outcomes of docetaxel retreatment which seems a plausible option in patients initially responding to docetaxel and maintaining a minimum progression-free interval of 3-6 months. In this review, a summary of the clinical evidence and potential concerns for the use of DR in patients with metastatic prostate cancer will be presented. Key Messages: Pivotal trials of docetaxel in metastatic castrate-sensitive prostate cancer as well as metastatic castrate-resistant prostate cancer have not reported on the outcomes of DR except in the GETUG-AFU 15 trial where the outcomes were disappointing. Based on the published retrospective data, DR may be effective in patients who initially responded to docetaxel and maintained a progression-free interval exceeding 6 months.

Correlation of Prostate-specific Antigen Kinetics with Overall Survival and Radiological Progression-free Survival in Metastatic Castration-sensitive Prostate Cancer Treated with Abiraterone Acetate plus Prednisone or Placebos Added to Androgen Deprivation Therapy: Post Hoc Analysis of Phase 3 LATITUDE Study

BACKGROUND

LATITUDE, a randomized, double-blind trial, compared abiraterone acetate and prednisone (AAP) + androgen deprivation therapy (ADT) versus placebo (PBO) + ADT in high-risk metastatic castration-sensitive prostate cancer (mCSPC).

OBJECTIVE

To assess the correlation of prostate-specific antigen (PSA) kinetics with overall survival (OS) and radiological progression-free survival (rPFS).

DESIGN, SETTING, AND PARTICIPANTS

A post hoc analysis of data from 597 men receiving AAP + ADT and 602 receiving PBO + ADT.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The associations of PSA-related outcomes (rates of confirmed 50% [PSA50] and 90% [PSA90] decline from baseline PSA [Prostate Cancer Working Group 2 criteria], rates of PSA < 0.2 ng/ml, median nadir PSA, time to PSA nadir [TPN], and time to PSA progression [TPP] with long-term outcomes [OS and rPFS]) were evaluated. Hazard ratios (HRs) were estimated using Cox proportional hazard model. Correlations of TPP with coprimary endpoints rPFS and OS were evaluated using Kendall's tau (KT).

RESULTS AND LIMITATIONS

AAP + ADT significantly delayed median TPP versus PBO + ADT (33.2 vs 7.4 mo; HR: 0.3, p <  0.001). TPP correlated with rPFS (KT = 0.921) and OS (KT = 0.666). In the AAP + ADT group, 91% had PSA50 and 79% had PSA90 responses (relative risk [RR]: 1.36 and 2.30, respectively; p <  0.001 for both comparisons vs PBO + ADT). Compared with nonresponders, PSA50 and PSA90 responders had reduced risk of death (RR: 0.44 and 0.12, respectively). At 6 mo, 40% receiving AAP + ADT and 6.5% receiving PBO + ADT achieved PSA ≤0.1 ng/ml, which was significantly associated with longer rPFS and OS. Median nadir PSA was 0.09 ng/ml with AAP + ADT versus 2.36 ng/ml with PBO + ADT. Median TPN (AAP + ADT, 6.4 mo; PBO + ADT, 3.8 mo) positively correlated with rPFS and OS.

CONCLUSIONS

Superior PSA response dynamics with AAP + ADT versus ADT + PBO strongly correlated with long-term outcomes of rPFS and OS in high-risk mCSPC.

PATIENT SUMMARY

We found that low prostate-specific antigen levels (≤0.1 ng/ml) after 6 mo may indicate a good long-term response to treatment. Our results need confirmation.

Survival Outcomes From a Cumulative Analysis of Worldwide Observational Studies on Sequential Use of New Agents in Metastatic Castration-Resistant Prostate Cancer

INTRODUCTION

The sequential use of a number of new agents (NAs) have improved the overall survival (OS) of patients with metastatic castration-resistant prostate cancer whose disease progresses after docetaxel (DOC) treatment. The aim of this study was to assess the cumulative survival outcomes of different sequencing strategies by evaluating the individual data from published studies of patients treated with a post-DOC treatment sequence of 2 NAs.

PATIENTS AND METHODS

The patients' individual data were analyzed to investigate whether different sequencing strategies lead to differences in OS.

RESULTS

We analyzed the data of 1099 evaluable patients. Among the patients treated with a second-line new hormone agent (NHA), median OS from the start of third-line treatment was significantly longer in the patients treated with cabazitaxel (CABA) than in those treated with abiraterone acetate or enzalutamide. Median cumulative OS (cumOS) from the start of second-line treatment was 21.1 months in the patients who received NHA then NHA, 22.1 months in those who received NHA then CABA, and 21.0 months in those who received CABA then NHA. Among the patients with a second-line progression-free survival of ≥6 months, median cumOS was significantly longer in patients who received CABA-including sequences than in those treated with NHA then NHA sequences (29.5 vs. 24.8 months; P = .03).

CONCLUSION

Our findings suggest that the sequential use of NAs with different mechanisms of action improves cumOS regardless of the order in which they are administered, thus supporting the hypothesis of cross-resistance between the 2 NHAs.

Sequencing strategies in the new treatment landscape of prostate cancer

Over the last 10 years, a number of new agents approved for the treatment of metastatic castration-resistant prostate cancer have led to a significant improvement in overall survival. The addition of new agents to androgen deprivation therapy has also allowed a paradigmatic change in the treatment of metastatic hormone-sensitive prostate cancer by improving overall survival in comparison with androgen deprivation therapy alone. Furthermore, recent data concerning the efficacy of three different androgen receptor-targeting agents in patients with nonmetastatic castration-resistant prostate cancer have opened up new scenarios for future patients' management. Defining the best sequencing strategies for men with prostate cancer is a currently unmet medical need, and choosing treatment is often challenging for clinicians because of the lack of direct comparisons of the available agents. The aim of this paper is to provide a comprehensive review of the literature concerning current sequencing strategies for prostate cancer patients.

Management algorithms for metastatic prostate cancer

INTRODUCTION

Prostate cancer poses a significant lifetime risk to Canadian men. Treatment for metastatic prostatic cancer (mPCa) is an area of ongoing research with a lack of up-to-date clinical guidance. The multidisciplinary Canadian Genitourinary Research Consortium (GURC) determined that additional guidance focusing on management of mPCa was warranted.

METHODS

The most up-to-date guidelines, consensus statements, and emerging phase 3 trials were identified and used to inform development of algorithms by a multidisciplinary genitourinary oncology panel outlining recommendations for the management of mPCa.

RESULTS

A single pan-Canadian guideline and five national and international guidelines or consensus statements published since 2015 were identified, along with two new phase 3 trials and one additional randomized comparison. Iterative GURC discussions led to the development of two mPCa algorithms: the first addressing management of newly diagnosed metastatic castration-sensitive prostate cancer (mCSPC) patients and the second addressing treatment of patients with metastatic castration-resistant prostate cancer (mCRPC). For newly diagnosed mCSPC patients with high-volume/high-risk disease, either docetaxel or abiraterone acetate and prednisone (AAP) added to androgen-deprivation therapy (ADT) is recommended. The addition of radiotherapy to ADT is suggested for those with low-volume disease and/or AAP to ADT for low-volume or low-risk disease. For first-line mCRPC, androgen receptor-axis-targeted (ARAT) therapy is recommended for most patients, while sequencing with docetaxel, radium-223, ARAT therapy, and/or cabazitaxel is recommended for later lines of therapy.

CONCLUSIONS

Two treatment algorithms were developed for the management of mPC and can be used by multidisciplinary specialist teams to guide treatment.

Activity and safety of metronomic cyclophosphamide in the modern era of metastatic castration-resistant prostate cancer

Aim: To evaluate activity of metronomic cyclophosphamide (mCTX) in heavily pretreated metastatic castration-resistant prostate cancer (mCRPC) patients. Patients & methods: We retrospectively evaluated a consecutive series of 74 mCRPC patients treated with at least one new agent after docetaxel failure, who received once-daily oral mCTX treatment at a fixed dose of 50 mg. Results: The treatment was well tolerated. Sixteen percent of the patients experienced a major biochemical response. Median progression-free survival was 4.0 months, and median overall survival was 8.1 months. Conclusions: In the modern context of mCRPC, mCTX may represent a valuable and inexpensive alternative to new agents, which have shown similar activity in heavily pretreated patients.

Docetaxel-rechallenge in castration-resistant prostate cancer: defining clinical factors for successful treatment response and improvement in overall survival

PURPOSE

The purpose of the study was to define clinical factors for successful treatment response and re-exposure to docetaxel in metastatic castration-resistant prostate cancer (mCRPC).

METHODS

An mCRPC database of patients receiving first-line docetaxel and rechallenge courses was established. Several clinical factors were evaluated for prediction of treatment response. Multivariate cox-regression analysis was used to define pre-treatment and treatment factors for survival.

RESULTS

Between 2005 and 2013, 94 patients with mCRPC were treated with docetaxel. Full data set and follow-up were available for 62 patients. Median follow-up was 84 m [interquartile range (IQR) 64-104 m]. Median biochemical progression-free survival (bPFS) and overall survival under docetaxel were 9 m (IQR 5-16 m) and 20 m (IQR 16-26 m), respectively. Partial PSA-response at first docetaxel-sequence (n = 62), rechallenge (n = 32), and third-sequence (n = 22) docetaxel was 48.4%, 31.6%, and 34.8%, respectively. Time from start of primary androgen deprivation to CRPC > 47 m was the only independent pre-treatment parameter to predict improved overall survival (Hazard Ratio 0.48, p = 0.015). Interestingly, there was a strong trend for improved overall survival in patients with high Gleason Score (Hazard Ratio 0.58; p = 0.08). Partial PSA-response at docetaxel-rechallenge (Hazard Ratio 0.31; p = 0.008) and treatment-free interval > 3 m (Hazard Ratio 3.49; p = 0.014) were the only independent predictive factors under taxane treatment for overall survival.

CONCLUSION

Despite novel hormonal drugs, docetaxel still plays an important role in the treatment of mCRPC. Patients with partial-PSA-response at rechallenge or a treatment-free interval > 3 m benefit most from docetaxel re-exposure.

Matrix metalloproteinase 7, soluble Fas and Fas ligand serum levels for predicting docetaxel resistance and survival in castration-resistant prostate cancer

OBJECTIVE

To assess the predictive value of pre-chemotherapy matrix metalloproteinase 7 (MMP-7), soluble Fas (sFas) and Fas ligand (FasL) serum levels, as well as their changes during therapy.

PATIENTS AND METHODS

Serum levels of MMP-7, Fas and FasL were determined by ELISA in 96 patients with castration-resistant prostate cancer (CRPC): 21 docetaxel-resistant patients who received one single series and 75 docetaxel-sensitive patients who received repeated series of docetaxel. In addition to the 96 pretreatment serum samples, 987 sera collected during chemotherapy were also analysed.

RESULTS

Higher pretreatment serum MMP-7, sFas and prostate-specific antigen (PSA) levels were significantly associated with both docetaxel resistance (P = 0.007, P = 0.001, P < 0.001, respectively) and shorter cancer-specific survival (P < 0.001, P = 0.041, P < 0.001, respectively). High MMP-7 level remained an independent predictor of both docetaxel resistance (hazard ratio [HR] 2.298, 95% confidence interval [CI]: 1.354-3.899; P = 0.002) and poor cancer-specific survival (HR 2.11, 95% CI: 1.36-3.30; P = 0.001) in multivariable analyses. Greater increase in MMP-7 levels in the second treatment holiday and greater increase in PSA levels in the first and second treatment holidays were predictive of survival.

CONCLUSIONS

Pretreatment serum MMP-7 levels may help to select patients with CRPC who are likely to benefit from docetaxel chemotherapy. Furthermore, MMP-7 levels alone or in combination with PSA levels could be used for therapy monitoring. Correlative studies embedded in clinical trials are necessary to validate these biomarkers for clinical decision-making.

A randomised phase II trial of docetaxel versus docetaxel plus carboplatin in patients with castration-resistant prostate cancer who have progressed after response to prior docetaxel chemotherapy: The RECARDO trial

BACKGROUND

Docetaxel is standard first-line chemotherapy for patients with metastatic castration-resistant prostate carcinoma (mCRPC). Docetaxel re-challenge has never been tested in a prospective randomised controlled study. As some studies support the addition of carboplatin to docetaxel, we performed a phase II trial investigating the combination of docetaxel plus carboplatin versus docetaxel re-treatment in docetaxel pre-treated mCRPC patients.

METHODS

Patients with mCRPC with a progression-free interval of ≥3 months after initial docetaxel treatment were randomised between docetaxel 75 mg/m² or docetaxel 60 mg/m² plus carboplatin AUC4. The primary end-point was progression-free survival (PFS; PSA/RECIST).

RESULTS

Owing to insufficient recruitment, the study was discontinued early after inclusion of 75 patients (targeted 150) PFS and overall survival (OS) were comparable between both groups (median PFS 12.7 months (95% CI 9.9-17.5 months) with docetaxel monotherapy and 11.7 months (95% CI 8.5-21.0 months) with combination therapy (p = 0.98); OS 18.5 months (95% CI 11.8-24.5 months) versus 18.9 months (95% CI 16.0-23.7 months) (p = 0.79). An interim analysis (SEQTEST) showed that the null hypothesis could already be excepted, and no significant difference between both study arms was expected if inclusion would be completed. The incidence of grade 3-4 infections and gastrointestinal side-effects was numerical higher in the carboplatin arm (p = 0.056).

CONCLUSION

This early terminated study suggests no benefit from the addition of carboplatin to docetaxel re-treatment in patients with mCRPC, whereas the combination resulted in more toxicity. Re-treatment with docetaxel monotherapy appears to be feasible, save and effective for patients with mCRPC and an initial good response to docetaxel.

TRIAL REGISTRATION

NTR3070.

Docetaxel Rechallenge in a Heavily Pretreated Patient With Castration-Resistant Prostate Cancer: A Case Report and Review of Literature

Chemotherapy agents for patients with metastatic castration-resistant prostate cancer (mCRPC) include docetaxel and cabazitaxel. Although docetaxel is approved in the first-line treatment setting, a few studies have shown that selected patients can benefit from docetaxel rechallenge.We, here, report the case of a heavily pretreated mCRPC patient who reported clinical benefit from receiving docetaxel after previous exposure to docetaxel, cabazitaxel, abiraterone, and enzalutamide.After 4 cycles of treatment, patient's performance status had improved to 1, the hemoglobin level was 12.9 g/dL and his serum prostate specific antigen levels were reduced by >70%, with no treatment-related adverse events.Although docetaxel rechallenge is a therapeutic option for selected patients, the risk of cumulative toxicity described in literature must be carefully considered.As the risk of cabazitaxel-related cumulative toxicity is probably lower, retreatment with cabazitaxel rather than docetaxel may also be an option in the setting of heavily pretreated mCRPC patients.

Novel non-AR therapeutic targets in castrate resistant prostate cancer

Castrate resistant prostate cancer (CRPC) remains a disease with significant morbidity and mortality. The recent approval of abiraterone and enzalutamide highlight the improvements which can be made targeting the androgen receptor (AR) axis. Nonetheless, resistance inevitably develops and there is continued interest in targeting alternate pathways which cause disease resistance and progression. Here, we review non-AR targets in CRPC, with an emphasis on novel agents now in development. This includes therapeutics which target the tumour microenvironment, the bone metastatic environment, microtubules, cellular energetics, angiogenesis, the stress response, survival proteins, intracellular signal transduction, DNA damage repair and dendritic cells. Understanding the hallmarks of prostate cancer resistance in CRPC has led to the identification and development of these new targets. We review the molecular rationale, as well at the clinical experience for each of these different classes of agents which are in clinical development.

Systemic Medical Treatment in Men with Metastatic Castration-Resistant Prostate Cancer: Recommendations for Daily Routine

The approval or clinical evaluation of several new agents - cabazitaxel, abiraterone acetate, enzalutamide, sipuleucel-T, and radium-223 - has significantly changed the management of patients with metastatic castration-resistant prostate cancer (mCRPC) prior to or after docetaxel-based chemotherapy. All of these agents have resulted in a significant survival benefit as compared to their control group. However, treatment responses might differ depending on the associated comorbidities and the extent and biological aggressiveness of the disease. Furthermore, treatment-associated side effects differ between the various drugs. As new drugs become approved, new treatment strategies and markers to best select which patients will best respond to which drug are needed. It is the aim of the current article to i) summarize the data of established treatment options in mCRPC, ii) highlight new developments in medical treatment, iii) provide clinically useful algorithms for the daily routine, and iv) point out future developments in medical treatment.

Intermittent docetaxel chemotherapy as first-line treatment for metastatic castration-resistant prostate cancer patients

AIMS

The intermittent administration of chemotherapy is a means of preserving patients' quality of life (QL). The aim of this study was to verify whether the intermittent administration of docetaxel (DOC) improves the patients' QL.

PATIENTS & METHODS

All patients received DOC 70 mg/m(2) every 3 weeks for eight cycles. The patients were randomized to receive DOC continuously or with a fixed 3-month interval after the first four DOC courses.

RESULTS

The study involved 148 patients. There was no difference in QL between the groups receiving intermittent or continuous treatment. Intermittence had no detrimental effects on disease control.

CONCLUSION

Although feasible and not detrimental, our results showed that true intermittent chemotherapy in metastatic castration-resistant prostate cancer patients failed to improve the patients' QL.

Is there still a place for docetaxel rechallenge in prostate cancer?

Three-weekly docetaxel plus prednisone is the standard first-line cytotoxic treatment for patients with metastatic castrate-resistant prostate cancer (mCRPC). Today, several new treatment options are available for patients with tumor progression after first-line docetaxel: Abiraterone, enzalutamide, cabazitaxel, sipuleucel-T immunotherapy, and the radionuclide radium-223. However, despite the evolving scenario in CRPC treatment, the optimal sequencing of the innovative therapies remains unclear. The reintroduction of docetaxel at the occurrence of disease progression after a drug holiday (docetaxel rechallenge) was often proposed, and this chemotherapeutic agent showed to maintain antitumor activity in mCRPC patients. Docetaxel rechallenge may still constitute a valid treatment option mainly for patients with favorable response to first-line docetaxel, at least > 3 mo progression-free interval, age less than 75 years, good performance status, and acceptable docetaxel toxicity. The risk of cumulative toxicity must be evaluated, since sensory neuropathy, nail disorders and fatigue might occur on docetaxel rechallenge.

Docetaxel rechallenge in metastatic castration-resistant prostate cancer: any place in the modern treatment scenario? An intention to treat evaluation

BACKGROUND

We evaluated the possible advantages of a docetaxel (DCT) rechallenge strategy in metastatic castration-resistant prostate cancer (mCRPC) patients, also given the possible earlier positioning of this treatment option in the modern scenario.

PATIENTS & METHODS

All mCRPC patients planned for DCT chemotherapy rechallenge in our institutions were evaluated.

RESULTS

Of 128 patients, 98 achieved disease control on the initial DCT round. After a treatment holiday of 8.3 months, the 98 responsive patients underwent a second DCT round, with 56 cases achieving again disease control. After a 5.7-month off-treatment period, 32 of these cases underwent a third DCT round, and 16 responded. Lastly, after a further 4.2-month treatment holiday, eight patients underwent a fourth DCT round and two responded. Median time to definitive disease progression for the whole population was 16.4 months.

CONCLUSIONS

Rechallenge with DCT may be considered a suitable treatment option for mCRPC patients recurring after a successful DCT chemotherapy. The interest in this strategy may be increased because of the showed efficacy of early DCT chemotherapy in patients with bulky disease (CHAARTED study) and the potential lower efficacy of the new hormonal agents abiraterone acetate and enzalutamide when used in a immediate sequencing.

Metastatic castration-resistant prostate cancer: time for innovation

Androgen deprivation is the mainstay of advanced prostate cancer treatment. Despite initial responses, almost all patients progress to castration-resistant prostate cancer (CRPC). The understanding of the biology of CRPC and the evidence that CRPC still remains driven by androgen receptor signaling led to the discovery of new therapeutic targets. In the last few years, large Phase III trials showed improvements in survival and outcomes and led to the approval of a CYP17 inhibitor (abiraterone), an androgen receptor antagonist (enzalutamide), the taxane cabazitaxel, an α-emitter (radium-223), the bone resorption-targeting drug denosumab and an immunotherapy (sipuleucel-T). This article describes the molecular mechanisms underlying castration resistance, discusses recent and ongoing trials and offers some insights into identifying the best sequence of new drugs.

Rechallenge of docetaxel combined with epirubicin given on a weekly schedule in advanced castration-resistant prostate cancer patients previously exposed to docetaxel and abiraterone acetate: a single-institution experience

The aim of this paper was to evaluate the activity and tolerability of weekly docetaxel (D) combined with weekly epirubicin (EPI) in patients with advanced castrate-resistant prostate cancer (CRPC) previously exposed to D and abiraterone acetate (AA). Locally advanced or metastatic CRPC patients with 0-2 performance status, who had progressed after D and AA therapy, were included in the study. Previous treatment with chemotherapy agent cabazitaxel was also admitted. Treatment consisted of D 30 mg/m(2) intravenously (i.v.) and EPI 30 mg/m(2) i.v., every week (D/EPI). Chemotherapy was administered until disease progression or unacceptable toxicity. In our institution, twenty-six patients received D/EPI: their median age was 72 years (range 59-83 years). Twenty-three (88.5%) patients had bone metastases. A decrease in PSA levels ≥50% was observed in seven patients (26.9%, 95% CI: 0.11-0.47); of these, five had achieved a ≥50% PSA response during prior first-line D and six had achieved a PSA response during prior AA Among the subjects who were symptomatic at baseline, pain was reduced in nine patients (38.1%) with a significant decrease in analgesic use. Median progression-free survival was 4.4 months (95% CI, 3-5.2), and median overall survival was 10.7 months (95% CI, 8.9-18.4). Treatment was well tolerated and no grade 4 toxicities were observed. Our findings suggest that weekly D/EPI is feasible and active in heavily pretreated advanced CRPC patients and seem to support the hypothesis that the addition of EPI to D may lead to overcome the resistance to D in a subgroup of patients.

Rechallenge of docetaxel combined with epirubicin given on a weekly schedule in advanced castration-resistant prostate cancer patients previously exposed to docetaxel and abiraterone acetate: a single-institution experience

The aim of this paper was to evaluate the activity and tolerability of weekly docetaxel (D) combined with weekly epirubicin (EPI) in patients with advanced castrate-resistant prostate cancer (CRPC) previously exposed to D and abiraterone acetate (AA). Locally advanced or metastatic CRPC patients with 0-2 performance status, who had progressed after D and AA therapy, were included in the study. Previous treatment with chemotherapy agent cabazitaxel was also admitted. Treatment consisted of D 30 mg/m(2) intravenously (i.v.) and EPI 30 mg/m(2) i.v., every week (D/EPI). Chemotherapy was administered until disease progression or unacceptable toxicity. In our institution, twenty-six patients received D/EPI: their median age was 72 years (range 59-83 years). Twenty-three (88.5%) patients had bone metastases. A decrease in PSA levels ≥50% was observed in seven patients (26.9%, 95% CI: 0.11-0.47); of these, five had achieved a ≥50% PSA response during prior first-line D and six had achieved a PSA response during prior AA Among the subjects who were symptomatic at baseline, pain was reduced in nine patients (38.1%) with a significant decrease in analgesic use. Median progression-free survival was 4.4 months (95% CI, 3-5.2), and median overall survival was 10.7 months (95% CI, 8.9-18.4). Treatment was well tolerated and no grade 4 toxicities were observed. Our findings suggest that weekly D/EPI is feasible and active in heavily pretreated advanced CRPC patients and seem to support the hypothesis that the addition of EPI to D may lead to overcome the resistance to D in a subgroup of patients.

Real-World Treatment Patterns in Men with Castration- Resistant Prostate Cancer Receiving Docetaxel

Background: Docetaxel has been a standard of care for castration-resistant prostate cancer (CRPC) in the United States since 2004, yet little has been reported on its patterns of use in routine practice. To help understand these patterns, a retrospective study was conducted and is reported here. Methods: Medical records from 394 patients treated in the United States were reviewed. Data were collected by 48 physicians from oncology (patient N=344) and 8 physicians from urology (patient N=50) practices. Inclusion criteria were: CRPC diagnosed between 2004 and 2010; received docetaxel; discontinued docetaxel due to rising prostate-specific antigen (PSA), progression of bone lesions, or progression of nodal or visceral metastases. Data were collected from physicians using an internet-based case report form. We evaluated patient demographics, characteristics of the docetaxel regimen, and other treatments used until docetaxel discontinuation. Results: Patients had a mean [±SD] age of 66.5 [8.9] years, the majority (63%) were white, and geographic dispersion was similar to the US population. The majority of patients initiated docetaxel between 2008 and 2010. After CRPC diagnosis, 8% of patients had initiated another cancer-directed therapy before starting docetaxel. Most (78.9%) patients initiated docetaxel with prednisone, while 18.5% initiated docetaxel alone and 2.6% initiated with other medications. Half of patients initiated docetaxel within 1 month after CRPC diagnosis, while 25% started ≥6 months later. Other non-chemotherapy treatments used with docetaxel were hormonal therapy (22.8%), radiotherapy (17.3%), and surgery (4.1%). Most patients (75%) received ≥4 docetaxel cycles, half received ≥6 cycles, 25% received ≥8 cycles and 10% received ≥10 cycles. Increased tumor mass, with/without new bone lesions or rising PSA, was the most common reason for docetaxel discontinuation (74% of patients). Conclusions: Concordant with guidelines, docetaxel and prednisone was the preferred first-line chemotherapy regimen in CRPC patients reviewed for this study. However, one quarter of patients did not initiate docetaxel until ≥6 months after CRPC diagnosis and total exposure varied considerably, with only 10% receiving ≥10 cycles. Future studies are needed to describe specific reasons explaining timing of docetaxel initiation and duration of exposure in some CRPC patients.

Docetaxel rechallenge after an initial good response in patients with metastatic castration-resistant prostate cancer

OBJECTIVE

To evaluate the benefit of docetaxel rechallenge in patients with metastatic castration-resistant prostate cancer (mCRPC) relapsing after an initial good response to first-line docetaxel.

PATIENTS AND METHODS

We retrospectively reviewed the records of consecutive patients with mCRPC with a good response to first-line docetaxel [serum prostate specific antigen (PSA) decrease ≥50%; no clinical/radiological progression]. We analysed the impact of management at relapse (docetaxel rechallenge or non-taxane-based therapy) on PSA response, symptomatic response (performance status/pain/analgesic consumption), and overall survival (OS). We used multivariate stepwise logistic regression to analyse potential predictors of a favourable outcome.

RESULTS

We identified 270 good responders to first-line docetaxel. The median progression-free interval (PFI) was 6 months from the last docetaxel dose. At relapse, 223 patients were rechallenged with docetaxel (82.5%) and 47 received non-taxane-based therapy. There was no significant difference in median OS {18.2 [95% confidence interval (CI) 16.1-22.00] and 16.8 [95%CI 13.4-21.5] months, respectively, P = 0.35}. However, good PSA response and symptom relief/stable disease were more frequent on docetaxel rechallenge (40.4% vs 10.6%, P < 0.001 for PSA). A PFI of >6 months and added estramustine predicted a good PSA response and symptomatic response on docetaxel rechallenge but only a PFI of >6 months predicted longer OS. Haemoglobin (<13 g/dL) and pain were associated with reduced OS. Docetaxel rechallenge increased the incidence of grade ≥3 sensory neuropathy, nail disorders and asthenia/fatigue.

CONCLUSIONS

Docetaxel rechallenge is a management option for responders to docetaxel with a PFI of >6 months, but did not prolong survival. Potential benefits should be weighed against the risk of cumulative toxicity.

Bioclinical parameters driving decision-making of subsequent lines of treatment in metastatic castration-resistant prostate cancer

Different options are available as second-line treatment of metastatic castrate-resistant prostate cancer: cabazitaxel, abiraterone, and enzalutamide. Phase III studies evaluating cabazitaxel and the two hormonal agents have been shown to significantly prolong overall survival compared to mitoxantrone and placebo, respectively. Several studies have also demonstrated feasibility and activity of docetaxel rechallenge in case of a sufficient progression-free interval (3-6 months), good performance status, and previous acceptable safety profile, thus providing an additional treatment option in clinical practice. Clinical and biological parameters should be considered to tailor II line treatment. In clinical practice, we can primarily evaluate patients' fitness according to age, performance status, symptomatic disease, comorbidities, and expected safety profile of each drug. Different prognostic/predictive factors may be considered, such as presence of bone-limited or visceral metastases, length of androgen deprivation therapy (ADT) before chemotherapy, time to progression after docetaxel, Gleason score, PSA doubling time, and serum testosterone, even if their clinical relevance is still debated. This review will discuss current options of innovative drugs sequencing and selection according to bioclinical parameters.

EAU guidelines on prostate cancer. Part II: Treatment of advanced, relapsing, and castration-resistant prostate cancer

OBJECTIVE

To present a summary of the 2013 version of the European Association of Urology (EAU) guidelines on the treatment of advanced, relapsing, and castration-resistant prostate cancer (CRPC).

EVIDENCE ACQUISITION

The working panel performed a literature review of the new data (2011-2013). The guidelines were updated, and levels of evidence and/or grades of recommendation were added to the text based on a systematic review of the literature that included a search of online databases and bibliographic reviews.

EVIDENCE SYNTHESIS

Luteinising hormone-releasing hormone (LHRH) agonists are the standard of care in metastatic prostate cancer (PCa). LHRH antagonists decrease testosterone without any testosterone surge, and they may be associated with an oncologic benefit compared with LHRH analogues. Complete androgen blockade has a small survival benefit of about 5%. Intermittent androgen deprivation results in noninferior oncologic efficacy when compared with continuous androgen-deprivation therapy (ADT) in well-selected populations. In locally advanced and metastatic PCa, early ADT does not result in a significant survival advantage when compared with delayed ADT. Relapse after local therapy is defined by prostate-specific antigen (PSA) values >0.2 ng/ml following radical prostatectomy (RP) and >2 ng/ml above the nadir and after radiation therapy (RT). Therapy for PSA relapse after RP includes salvage RT (SRT) at PSA levels <0.5 ng/ml and SRP or cryosurgical ablation of the prostate in radiation failures. Endorectal magnetic resonance imaging and 11C-choline positron emission tomography/computed tomography (PET/CT) are of limited importance if the PSA is <1.0 ng/ml; bone scans and CT can be omitted unless PSA is >20 ng/ml. Follow-up after ADT should include analysis of PSA and testosterone levels, and screening for cardiovascular disease and metabolic syndrome. Treatment of CRPC includes sipuleucel-T, abiraterone acetate plus prednisone (AA/P), or chemotherapy with docetaxel at 75mg/m(2) every 3 wk. Cabazitaxel, AA/P, enzalutamide, and radium-223 are available for second-line treatment of CRPC following docetaxel. Zoledronic acid and denosumab can be used in men with CRPC and osseous metastases to prevent skeletal-related complications.

CONCLUSIONS

The knowledge in the field of advanced, metastatic, and castration-resistant PCa is rapidly changing. These EAU guidelines on PCa summarise the most recent findings and put them into clinical practice. A full version is available at the EAU office or at www.uroweb.org.

PATIENT SUMMARY

We present a summary of the 2013 version of the European Association of Urology guidelines on treatment of advanced, relapsing, and castration-resistant prostate cancer (CRPC). Luteinising hormone-releasing hormone (LHRH) agonists are the standard of care in metastatic prostate cancer (PCa). LHRH antagonists decrease testosterone without any testosterone surge, and they might be associated with an oncologic benefit compared with LHRH analogues. Complete androgen blockade has a small survival benefit of about 5%. Intermittent androgen deprivation results in noninferior oncologic efficacy when compared with continuous androgen-deprivation therapy (ADT) in well-selected populations. In locally advanced and metastatic PCa, early ADT does not result in a significant survival advantage when compared with delayed ADT. Relapse after local therapy is defined by prostate-specific antigen (PSA) values >0.2 ng/ml following radical prostatectomy (RP) and >2 ng/ml above the nadir and after radiation therapy. Therapy for PSA relapse after RP includes salvage radiation therapy at PSA levels <0.5 ng/ml and salvage RP or cryosurgical ablation of the prostate in radiation failures. Multiparametric magnetic resonance imaging and 11C-choline positron emission tomography/computed tomography (PET/CT) are of limited importance if the PSA is <1.0 ng/ml; bone scans, and CT can be omitted unless PSA is >20 ng/ml. Follow-up after ADT should include analysis of PSA and testosterone levels, and screening for cardiovascular disease and metabolic syndrome. Treatment of castration-resistant CRPC includes sipuleucel-T, abiraterone acetate plus prednisone (AA/P), or chemotherapy with docetaxel 75 mg/m(2) every 3 wk. Cabazitaxel, AA/P, enzalutamide, and radium-223 are available for second-line treatment of CRPC following docetaxel. Zoledronic acid and denosumab can be used in men with CRPC and osseous metastases to prevent skeletal-related complications. The guidelines reported should be adhered to in daily routine to improve the quality of care in PCa patients. As we have shown recently, guideline compliance is only in the area of 30-40%.

Prostate-specific antigen response rate of sequential chemotherapy in castration-resistant prostate cancer: the results of real life practice

Purpose:

Prostate-specific antigen (PSA) response rate (>50% PSA decline in pretreatment PSA following chemotherapy) carries a significant survival advantage in castration-resistant prostate cancer (CRPC). We compared PSA response rates in first-, second- and third-line chemotherapy after failure of previous chemotherapy according to chemotherapeutic agents.

Methods:

We retrospectively evaluated the oncological outcomes and PSA response rates of 384 patients with CRPC, who were treated with chemotherapy and had histologically proven adenocarcinoma of the prostate with failure after androgen ablation therapy between 1991 and 2012, at Asan Medical Center.

Results:

In 384 eligible patients, the median age was 67.5 years. The median pretreatment PSA and initial Gleason scores at baseline were 92.4 ng/mL (range, 2.0 to 6,370 ng/mL) and 9 (range, 6 to 10), respectively. The time from first diagnosis of prostate cancer to CRPC was 23 months (range, 1 to 164 months). As first-line chemotherapy, 245 patients (63.8%) received estramustine, 91 (23.7%) received docetaxel, and 39 (10.2%) received mitoxantrone. The PSA response rates were 39.6%, 51.6%, and 46.2%, respectively. Of 169 patients with second-line chemotherapy, estramustine was 15 (8.9%), docetaxel was 84 (49.7%), and mitoxantrone was 52 (30.8%). PSA response rates were 57.1%, 52%, and 28.0%, respectively. Of 81 patients with third-line chemotherapy, estramustine was 18 (22.2%), docetaxel was 16 (19.8%), and mitoxantrone was 28 (34.6%). The PSA response rates were 41.2%, 53.8%, and 11.1%, respectively. Declines in serum PSA levels of at least 50% occurred more frequently after treatment with docetaxel than with other chemo-agents regardless of second-and third-line chemotherapy. Even in third-line chemothrapy, docetaxel maintained the PSA response rate, whereas the PSA response rate of other agents, including mitoxantrone, decreased in patients in whom prior therapy failed.

Conclusions:

Docetacel was the most effective chemotherapeutic agent in second- and third-line trials of chemotherapy in Korean CRPC patients. Although docetaxel is not used as first-line chemotherapy, and new agents are not available for therapy in CRPC patients, we can consider docetaxel a second- or third-line chemotherapy in CRPC.

Role of the EpCAM (CD326) in prostate cancer metastasis and progression

Despite significant advances in surgery, radiotherapy and chemotherapy to treat prostate cancer (CaP), many patients die of secondary disease (metastases). Current therapeutic approaches are limited, and there is no cure for metastatic castration-resistant prostate cancer (CRPC). Epithelial cell adhesion molecule (EpCAM, also known as CD326) is a transmembrane glycoprotein that is highly expressed in rapidly proliferating carcinomas and plays an important role in the prevention of cell-cell adhesion, cell signalling, migration, proliferation and differentiation. Stably and highly expressed EpCAM has been found in primary CaP tissues, effusions and CaP metastases, making it an ideal candidate of tumour-associated antigen to detect metastasis of CaP cells in the circulation as well as a promising therapeutic target to control metastatic CRPC disease. In this review, we discuss the implications of the newly identified roles of EpCAM in terms of its diagnostic and metastatic relevance to CaP. We also summarize EpCAM expression in human CaP and EpCAM-mediated signalling pathways in cancer metastasis. Finally, emerging and innovative approaches to the management of the disease and expanding potential therapeutic applications of EpCAM for targeted strategies in future CaP therapy will be explored.

Perspectives on treatment of metastatic castration-resistant prostate cancer

The arrival of several new agents--cabazitaxel, abiraterone acetate, enzalutamide, and radium-223--is changing the treatment options and management of patients with metastatic castration-resistant prostate cancer (mCRPC). Many other novel agents are also being investigated. As new drugs become approved, new treatment strategies and markers to best select which patients will best respond to which drug are needed. This review article is a summary of a European Treatment Practices Meeting, which was convened to discuss these latest data on novel agents and current treatment strategies in the mCRPC setting.

Evolving landscape and novel treatments in metastatic castrate-resistant prostate cancer

Treatment options for castrate-resistant prostate cancer (CRPC) have advanced in recent years and significantly improved the outlook for patients with this aggressive and lethal disease. Further understanding of the biology of CRPC has led to several new targeted therapies and continues to emphasize the importance of androgen receptor (AR) directed therapy. The treatment landscape is rapidly changing and further biologically rationale, biomarker-based ongoing clinical trials are needed. We review the recent results of major clinical trials in CRPC. New and investigational agents now in clinical evaluation are reviewed including inhibitors of angiogenesis, microtubules, chaperones, AR and intracellular kinases, as well as immunotherapy, radiopharmaceuticals and bone-targeted agents. The recent improvement in prognosis for CRPC brings continued optimism for further improvements. Thoughtful planning of clinical trials and further understanding of the mechanisms of resistance to therapies will allow for continued progress in patient care.

Docetaxel: a review of its use for the first-line treatment of advanced castration-resistant prostate cancer

Docetaxel (Taxotere®) is a well established anti-mitotic chemotherapy agent. Among other therapeutic indications, docetaxel plus prednisone is indicated for first-line chemotherapy in patients with castration-resistant prostate cancer (CRPC). Docetaxel every 3 weeks plus continuous prednisone has been standard first-line chemotherapy in CRPC since demonstrating improved survival compared with the previous standard regimen, mitoxantrone plus prednisone, in the phase III TAX 327 trial in 2004. Since that time, docetaxel has been combined with various agents that demonstrated additive or synergistic activity in preclinical studies in an effort to further improve outcomes, but to date, overall survival has not been extended compared with docetaxel plus prednisone. However, several promising agents are emerging with a potential role in docetaxel-based combinations based on efficacy and manageable toxicity, including bevacizumab, dasatinib and atrasentan. In the TAX 327 trial, neutropenia was relatively common in the group receiving 3-weekly docetaxel plus prednisone, but infection was rare. The tolerability of a weekly docetaxel regimen also administered in this trial was not significantly different to that of the 3-weekly regimen, except for a lower incidence of grade 3 or 4 neutropenia. However, weekly or 2-weekly docetaxel administration schedules may have a place in very elderly or frail patients in order to improve tolerability compared with the 3-weekly regimen. In conclusion, docetaxel every 3 weeks plus prednisone remains the optimum first-line chemotherapy for most patients with advanced CRPC until such time that ongoing research with docetaxel and emerging therapeutic agents can demonstrate improved survival.