Prospective Assessment of Bone Metabolism Biomarkers and Survival in Metastatic Castration-resistant Prostate Cancer Patients Treated with Radium-223: The PRORADIUM Study

BACKGROUND

Radium-223 is an active therapy option for bone metastatic castration-resistant prostate cancer (mCRPC). The lack of adequate biomarkers for patient selection and response assessment are major drawbacks for its use.

OBJECTIVE

To assess the prognostic value of bone metabolism biomarkers (BMBs) in ra-223-treated mCRPC patients.

DESIGN, SETTING, AND PARTICIPANTS

A prospective cohort study of mCRPC patients treated with Ra-223 (PRORADIUM study: NCT02925702) was conducted.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The main objective of the study was to evaluate the association between high (≥median) baseline values in at least three bone formation (bone alkaline phosphatase [BAP] and C-terminal type-I collagen propeptide) and bone resorption (N-terminal telopeptide and pyridinoline) biomarkers, and survival. The independent prognostic value of each BMB was also assessed. The association with time to radiographic, clinical, and prostate-specific antigen (PSA) progression; time to skeletal-related events; and PSA response were secondary objectives. Multivariable (MV) Cox-regression models were evaluated.

RESULTS AND LIMITATIONS

A total of 169 patients were included. Of the patients, 70.4% received Ra-223 in second/third line; 144 (85.2%) were Eastern Cooperative Oncology Group 0-1, 126 (74.6%) were in pain, and 80 (47.5%) had more than ten bone metastases. Sixty-seven (39.6%) patients had elevation in at least three BMBs. The median overall survival was 12.1 mo (95% confidence interval [CI]: 10-14.7). No association was observed with other treatment-related secondary outcome parameters. Patients with high values in three or more BMBs had significantly worse survival (9.9 vs 15.2 mo; hazard ratio [HR]: 1.8 [95% CI: 1.3-2.5]; p < 0.001) in the univariate analysis, but not independent in the MV analysis (HR: 1.33; 95% CI: 0.89-2; p = 0.181). High baseline BAP was the only biomarker associated with survival in the MV model (HR: 1.89; 95% CI: 1.28-2.79; p = 0.001). Addition of BAP to the MV clinical model increased the area under the receiver operating characteristic curve 2-yr value from 0.667 to 0.755 (p = 0.003).

CONCLUSIONS

Biomarkers of bone formation, especially BAP, have prognostic value in mCRPC patients treated with radium-223. Its predictive value remains to be assessed, ideally in prospective, adequately powered, randomised clinical trials.

PATIENT SUMMARY

In this study, we evaluate the role of bone metabolism biomarkers to help improve the use of radium-223 as therapy for advanced prostate cancer. We found that bone alkaline phosphatase may be a suitable tool.

A correlative biomarker study and integrative prognostic model in chemotherapy-naïve metastatic castration-resistant prostate cancer treated with enzalutamide

BACKGROUND

There is a considerable need to incorporate biomarkers of resistance to new antiandrogen agents in the management of castration-resistant prostate cancer (CRPC).

METHODS

We conducted a phase II trial of enzalutamide in first-line chemo-naïve asymptomatic or minimally symptomatic mCRPC and analyzed the prognostic value of TMPRSS2-ERG and other biomarkers, including circulating tumor cells (CTCs), androgen receptor splice variant (AR-V7) in CTCs and plasma Androgen Receptor copy number gain (AR-gain). These biomarkers were correlated with treatment response and survival outcomes and developed a clinical-molecular prognostic model using penalized cox-proportional hazard model. This model was validated in an independent cohort.

RESULTS

Ninety-eight patients were included. TMPRSS2-ERG fusion gene was detected in 32 patients with no differences observed in efficacy outcomes. CTC detection was associated with worse outcome and AR-V7 in CTCs was associated with increased rate of progression as best response. Plasma AR gain was strongly associated with an adverse outcome, with worse median prostate specific antigen (PSA)-PFS (4.2 vs. 14.7 m; p < 0.0001), rad-PFS (4.5 vs. 27.6 m; p < 0.0001), and OS (12.7 vs. 38.1 m; p < 0.0001). The clinical prognostic model developed in PREVAIL was validated (C-Index 0.70) and the addition of plasma AR (C-Index 0.79; p < 0.001) increased its prognostic ability. We generated a parsimonious model including alkaline phosphatase (ALP); PSA and AR gain (C-index 0.78) that was validated in an independent cohort.

CONCLUSIONS

TMPRSS2-ERG detection did not correlate with differential activity of enzalutamide in first-line mCRPC. However, we observed that CTCs and plasma AR gain were the most relevant biomarkers.

Plasma androgen receptor and response to adapted and standard docetaxel regimen in castration-resistant prostate cancer: A multicenter biomarker study

BACKGROUND

Plasma AR status has been identified as a potential biomarker of response in metastatic castration-resistant prostate cancer (mCRPC) patients receiving docetaxel or AR-targeted therapies. However, the relevance of plasma AR in the overall management of CRPC patients receiving different docetaxel doses is unknown.

PATIENTS AND METHODS

This was a multi-institution study of associations between baseline plasma AR copy number status, assessed by droplet digital PCR, and outcome in 325 mCRPC patients receiving docetaxel at standard or adapted regimen at the discretion of the treating physician. Upon analysis, patients were assigned randomly to either a training (n = 217) or validation (n = 108) cohort.

RESULTS

In the training cohort, AR-gained patients treated with adapted docetaxel regimen had a significantly worse median progression-free survival (PFS) (3.8 vs 6.3 months, hazard ratio [HR] 2.58, 95% confidence interval [CI] 1.34-4.95, p < 0.0001), median overall survival (10.8 vs 20.6 months, HR 1.98, 95% CI 1.09-3.62, p = 0.0064) and PSA response (PSA > -50%: odds ratio 4.88 95%CI 1.55-14.32, p = 0.013) as compared to plasma AR normal patients. These findings were all confirmed in the validation cohort. However, in patients treated with standard docetaxel regimen, these differences were not seen. The interaction between AR CN status and dose reduction of docetaxel was considered as independent factor for PFS in both the training and validation cohort (HR 2.84, 95% CI 1.41-5.73, p = 0.003, and HR 4.79, 95% CI 1.79-12.82, p = 0.002).

CONCLUSION

Despite the retrospective non-randomised design of this study, our hypothesis-generating findings could suggest plasma AR as a potential biomarker for optimal docetaxel timing and dose in mCRPC patients. Prospective trials are warranted.

Association of androgen receptor signature and RB1, PTEN, TP53 gene expression with clinical outcome in metastatic hormone-sensitive prostate cancer treated with docetaxel and androgen deprivation therapy

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Background: Androgen deprivation therapy (ADT) with docetaxel or new antiandrogens has demonstrated a survival benefit in metastatic hormone-sensitive prostate cancer (mHSPC). However, treatment selection for individual patients (pts) remains a challenge. We propose that TMPRSS2-ERG and cell plasticity [neuroendocrine (NE), epithelial to mesenchymal transition (EMT)], immune-related, androgen receptor (AR) and tumor suppressor genes (TSG) ( RB1, PTEN and TP53) expression signatures may predict clinical outcome in mHSPC pts treated with ADT+docetaxel. Methods: This is a multicenter retrospective biomarker study performed in mHSPC pts treated with ADT+docetaxel. A customized panel of 184 genes was designed and tested in total mRNA from FFPE tumor samples by nCounter platform (Nanostring Technologies). Expression levels were correlated with castration resistance-free survival (CRPC-FS) (primary endpoint) and overall survival (OS) by Kaplan Meier and multivariate Cox modeling. A predictive modeling approach was performed with Bujar R package to develop a signature able to predict CRPC-FS. R (v.3.6.3) software was used for statistical analyses. Results: 136 pts were included, and 120 of them were eligible. Median age was 66.9 years (range 46.3-83.6). Gleason score was ≥ 8 in 80.8% of pts; 87.5% and 20.8% of pts had bone and visceral metastases, respectively. Median follow-up was 30.7 months (m) (range 5.5-70.6). 76 pts (63.3%) developed castration-resistant prostate cancer (CRPC). Median time to CRPC was 20 m (range 16.9-23.1) and median OS was not reached. High AR-signature expression independently correlated with longer CRPC-FS (HR 0.4, 95% CI 0.2-0.7, p = 0.003). Considering AR-signature individual gene expression, ARV7 was independently associated with shorter CRPC-FS (HR 1.7, 95% CI 1.2-2.4, p = 0.003). Low expression of all TSG ( PTEN, RB1 and TP53) independently correlated with shorter CRPC-FS (HR 0.3, 95% CI 0.2-0.7, p = 0.003) and OS (HR 0.2, 95% CI 0.1-0.5, p < 0.001). Similarly, low expression of 2 out of the 3 TSG genes or only RB1 plus PTEN were also independently associated with shorter CRPC-FS (HR 0.5, 95% CI 0.3-0.9, p = 0.015; HR 0.4, 95% CI 0.2-0.7, p = 0.003, respectively) and OS (HR 0.4, 95% CI 0.2-0.9, p = 0.027; HR 0.2, 95% CI 0.1-0.6, p = 0.001, respectively). TMPRSS2-ERG expression, NE, EMT and immune-related signatures were not associated with clinical outcome. Bujar analysis defined a 17-gene signature (including ARV7, RB1, PTEN, BRCA2 and ATM) that was able to discriminate pts at different risk of developing early CRPC. Conclusions: High AR-signature expression correlates with a longer CRPC-FS while ARV7 expression is associated with shorter CRPC-FS. Low expression of TSG is associated with an aggressive clinical evolution in mHSPC pts treated with ADT+taxanes.

SEOM clinical guidelines for the treatment of advanced prostate cancer (2020)

The treatment of advanced prostate cancer has evolved due to recent advances in molecular research and new drug development. Dynamic aberrations in the androgen receptor, DNA repair genes, PTEN-PI3K, and other pathways drive the behavior of advanced prostate cancer allowing a better selection of therapies in each patient. Tumor testing for BRCA1 and BRCA2 is recommended for patients with metastatic prostate cancer, also considering a broad panel to guide decisions and genetic counseling. In symptomatic metastatic patients, castration should be stared to palliate symptoms and prolong survival. In high-risk or high-volume metastatic hormone-naïve patients, castration should be combined with docetaxel, abiraterone, enzalutamide or apalutamide. Radiotherapy to the primary tumor combined with systemic therapy is recommended in low-volume mHNPC patients. In patients with non-metastatic castration-resistant tumors, risk stratification can define the frequency of imaging. Adding enzalutamide, darolutamide or apalutamide to these patients prolongs metastasis-free and overall survival, but potential adverse events need to be taken into consideration. The choice of docetaxel, abiraterone or enzalutamide for treating metastatic castration-resistant patients depends on previous therapies, with cabazitaxel being also recommended after docetaxel. Olaparib is recommended in BRCA1/BRCA2 mutated castration-resistant patients after progression on at least one new hormonal therapy. Aggressive variants of prostate cancer respond to platinum-based chemotherapy. To optimize treatment efficiency, oncologists should incorporate all of these advances into an overall therapeutic strategy.

Survival and New Prognosticators in Metastatic Seminoma: Results From the IGCCCG-Update Consortium

The classification of the International Germ-Cell Cancer Collaborative Group (IGCCCG) has been a major advance in the management of germ-cell tumors, but relies on data of only 660 patients with seminoma treated between 1975 and 1990. We re-evaluated this classification in a database from a large international consortium.

Circulating Androgen Receptor for Prognosis and Treatment Selection in Prostate Cancer

Analysis of androgen receptor (AR) status, particularly AR copy number, in plasma DNA is a minimally invasive method with the potential to identify treatment resistance in patients with castration-resistant prostate cancer (CRPC) starting enzalutamide or abiraterone. Patients with elevated plasma AR do not have worse outcomes than patients with normal plasma AR when treated with taxanes. Consequently, circulating AR may improve clinical decision-making between AR-directed therapies versus taxanes and probably also between adapted versus standard taxane regimens. The evidence indicates that circulating AR could have a role in overall CRPC management. Promising clinical implications of plasma AR testing are measurement in earlier stages of prostate cancer, disease monitoring, and within the context of a multiplex biomarker strategy to improve treatment selection for CRPC patients. PATIENT SUMMARY: Measurement of the copy number of androgen receptor genes in plasma is a promising tool for guiding personalised treatment in patients with castration-resistant prostate cancer. However, prospective trials to validate these findings are needed.

Expert recommendations on the management of patients with metastatic castration-resistant prostate cancer who progress after CHAARTED or LATITUDE

Objective

Our aim was to provide practical recommendations on the management of patients with metastatic castration-resistant prostate cancer (mCRPC) who have progressed after docetaxel plus androgen-deprivation therapy (ADT) or abiraterone plus ADT.

Methods

Systematic literature review (SLR), nominal group meeting, and Delphi process. A panel of 12 experts was established who defined the scope, users, and sections of the document. We performed an SLR in order to assess the efficacy and safety of available drugs in patients with mCRPC. Abstracts from the American Society of Oncology and European Society for Medical Oncology meetings were also examined. The results were discussed during an expert meeting in which 14 recommendations were generated. The level of agreement with the recommendations was also tested by 13 additional experts following the Delphi process. Recommendations were voted by means of scores ranging from 0 (total disagreement) to 10 (total agreement). We defined agreement when at least 70% of the experts voted ⩾7. Next, we assigned a level of evidence and grade to the recommendation using the Oxford Centre for Evidence-based Medicine Levels of Evidence, following which the final document was drafted.

Results

The literature search did not find any articles meeting the inclusion criteria. Finally, 13 out of 14 recommendations were accepted after two Delphi rounds (two were modified after the first round). They pertain to general and individual case-based treatment recommendations.

Conclusions

In mCRPC patients who have progressed after docetaxel or abiraterone plus ADT in the metastatic hormone-sensitive prostate cancer setting, these recommendations may support treatment decision-making, due to the lack of evidence or other globally accepted sequencing algorithms.

Benefit of prophylactic anticoagulation before and during first-line chemotherapy on patients with metastatic germ cell tumors

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Background: Recent trials randomising patients (pts) receiving systemic cancer therapy showed that prophylactic anticoagulation (PAK) halves the risk of venous thromboembolic events (VTE) and doubles the risk of bleeding (Khorana et al. & Carrier et al., both NEJM 2019). In pts with metastatic germ cell tumors (mGCT) VTE is a frequent complication but it remains unclear whether PAK should be recommended because the number of mGCT pts in those trials was small. We aimed to determine the risk of VTE before, during and after chemotherapy and in mGCT pts without and with risk factors for VTE (retroperitoneal lymph nodes, Khorana score, venous access device) and to calculate the number needed to treat (NNT) and number needed to harm (NNH) of PAK. Methods: This retrospective analysis included mGCT pts treated with first-line platinum-based chemotherapy. We excluded patients who received PAK, with a known history of coagulopathy or VTE and extracted data about VTE and bleeding events. Cumulative VTE incidence was calculate for patients without and with increasing number of known risk factors for VTEs. NNT and NNH were calculated by assuming similar hazard ratios (HR) to reduce VTEs and increase bleeding as previously published (HR 0.66 and 1.96, Khorana et al., NEJM 2019). Results: Out of 1039 pts, 132 (13%) presented with VTE, 6 (1%) with bleeding. One patients died of VTE and 1 because of bleeding. Patients without any VTE risk factors experience VTE in 20/347 (5%) which translated into a NNT of 55 compared to the NNH of 84 respectively. Before start of chemotherapy 52 (5%) pts (NNT=60) presented with VTE of which 22 were reported symptomatic 21 asymptomatic/incidentally detected VTE on staging scans (9 unknowns). During chemotherapy 79 (8%) pts (NNT=40) were diagnosed with VTE whereas 19 (2%) pts (NNT=162) were diagnosed with VTE after chemotherapy. Conclusions: Our analysis revealed that even mGCT patients without risk factors for VTE show a relevant cumulative VTE incidence of 7%. Especially before and during but not after chemotherapy the benefits of PAK to prevent VTE outweighs the small increased risk of bleeding.

Large retroperitoneal lymphadenopathy and increased risk of venous thromboembolism in patients receiving first-line chemotherapy for metastatic germ cell tumors: A study by the global germ cell cancer group (G3)

Background

Metastatic germ cell tumor (mGCT) patients receiving chemotherapy have increased risk of life‐threatening venous thromboembolism (VTE). Identifying VTE risk factors may guide thromboprophylaxis in this highly curable population.

Methods

Data were collected from mGCT patients receiving first‐line platinum‐based chemotherapy at 22 centers. Predefined variables included International Germ Cell Cancer Collaborative Group (IGCCCG) risk classification, long‐axis diameter of largest retroperitoneal lymph node (RPLN), Khorana score, and use of indwelling vascular access device (VAD). VTE occurring at baseline, during chemotherapy and within 90 days, was analyzed.

Results

Data from 1135 patients were collected. Median age was 31 years (range 10‐74). IGCCCG risk was 64% good, 20% intermediate, and 16% poor. VTE occurred in 150 (13%) patients. RPLN >3.5 cm demonstrated highest discriminatory accuracy for VTE (AUC 0.632, P < .001) and was associated with significantly higher risk of VTE in univariable analysis (22% vs 8%, OR 3.0, P < .001) and multivariable analysis (OR 1.8, P = .02). Other significant risk factors included, Khorana score ≥3 (OR 2.6, P = .008) and VAD use (OR 2.7, P < .001).

Conclusions

Large RPLN and VAD use are independent risk factors for VTE in mGCT patients receiving chemotherapy. VAD use should be minimized in this population and thromboprophylaxis might be considered for large RPLN.

Plasma Androgen Receptor Copy Number Status at Emergence of Metastatic Castration-Resistant Prostate Cancer: A Pooled Multicohort Analysis

PURPOSE

Increases in androgen receptor (AR) copy number (CN) can be detected in plasma DNA when patients develop metastatic castration-resistant prostate cancer. We aim to evaluate the association between AR CN as a continuous variable and clinical outcome.

PATIENTS AND METHODS

PCR2023 was an international, multi-institution, open-label, phase II study of abiraterone acetate plus prednisolone (AAP) or abiraterone acetate plus dexamethasone that included plasma AR assessment as a predefined exploratory secondary end point. Plasma AR CN data (ClinicalTrials.gov identifier: NCT01867710) from this study (n = 133) were pooled with data from the following three other cohorts: cohort A, which was treated with either AAP or enzalutamide (n = 73); the PREMIERE trial (ClinicalTrials.gov identifier: NCT02288936) of biomarkers for enzalutamide (n = 94); and a phase II trial from British Columbia (ClinicalTrials.gov identifier: NCT02125357) that randomly assigned men to either AAP or enzalutamide (n = 201). The primary outcome measures for the biomarker analysis were overall survival and progression-free survival.

RESULTS

Using multivariable fractional polynomials analysis using Cox regression models, a nonlinear relationship between plasma AR CN and outcome was identified for overall survival, where initially for small incremental gains in CN there was a large added hazard ratio that plateaued at higher CN. The CN cut point associated with the highest local hazard ratio was 1.92. A similar nonlinear association was observed with progression-free survival. In an exploratory analysis of PCR2023, the time from start of long-term androgen-deprivation therapy to start of AAP or abiraterone acetate plus dexamethasone was significantly shorter in patients with plasma AR CN of 1.92 or greater than patients with plasma AR CN of less than 1.92 (43 v 130 weeks, respectively; P = .005). This was confirmed in cohort A (P = .003), the PREMIERE cohort (P = .03), and the British Colombia cohort (P = .003).

CONCLUSION

Patients with metastatic castration-resistant prostate cancer can be dichotomized by a plasma AR CN cut point of 1.92. Plasma AR CN value of 1.92 or greater identifies aggressive disease that is poorly responsive to AR targeting and is associated with a prior short response to primary androgen-deprivation therapy.

Plasma AR status and cabazitaxel in heavily treated metastatic castration-resistant prostate cancer

BACKGROUND

Plasma androgen receptor (AR) copy number status has been identified as a potential biomarker of response in patients with metastatic castration-resistant prostate cancer (mCRPC) receiving docetaxel or the AR-targeted therapies abiraterone or enzalutamide. However, the relevance of plasma AR status in the context of cabazitaxel therapy is unknown.

PATIENTS AND METHODS

Between September 2011 and January 2018, pretherapy plasma samples were collected from 155 patients treated with second- or third-line cabazitaxel at standard or reduced dose in different biomarker protocols. Droplet digital polymerase chain reaction was used to identify plasma AR gain and normal samples. The primary objective was to evaluate associations of plasma AR status with treatment outcome. In an exploratory analysis, a comparison between plasma AR and treatment type was investigated by incorporating updated data from our prior study of 85 post-docetaxel patients receiving abiraterone or enzalutamide.

RESULTS

We observed a shorter median overall survival (OS) and progression-free survival (PFS) in AR-gained compared to AR-normal patients (OS 10.5 versus 14.1 months, hazard ratio (HR) = 1.44, 95% confidence interval [CI] 0.98-2.13, P = 0.064 and PFS 4.0 versus 5.0 months, HR = 1.47, 95% CI 1.05-2.07, P = 0.024). In patients with mCRPC receiving second-line therapies, a significant treatment interaction was observed between plasma AR and cabazitaxel versus AR-directed therapies for OS (P = 0.041) but not PFS (P = 0.244). In an exploratory analysis, AR-gained patients treated with initial reduced dose of cabazitaxel had a significantly shorter median OS (7.3 versus 11.5 months, HR = 1.95, 95% CI 1.13-3.38, P = 0.016) and PFS (2.7 versus 5.0 months, HR = 2.27, 95% CI 1.39-3.71, P = 0.001).

CONCLUSION

Plasma AR status has a potential clinical utility in patients being considered for cabazitaxel. Validation of these findings in prospective trials is warranted.

Plasma Androgen Receptor and Docetaxel for Metastatic Castration-resistant Prostate Cancer

Plasma androgen receptor (AR) gain identifies metastatic castration-resistant prostate cancer (mCRPC) patients with worse outcome on abiraterone/enzalutamide, but its relevance in the context of taxane chemotherapy is unknown. We aimed to evaluate whether docetaxel is active regardless of plasma AR and to perform an exploratory analysis to compare docetaxel with abiraterone/enzalutamide. This multi-institutional study was a pooled analysis of AR status, determined by droplet digital polymerase chain reaction, on pretreatment plasma samples. We evaluated associations between plasma AR and overall/progression-free survival (OS/PFS) and prostate-specific antigen (PSA) response rate in 163 docetaxel-treated patients. OS was significantly shorter in case of AR gain (hazard ratio [HR]=1.61, 95% confidence interval [CI]=1.08-2.39, p=0.018), but not PFS (HR=1.04, 95% CI 0.74-1.46, p=0.8) or PSA response (odds ratio=1.14, 95% CI=0.65-1.99, p=0.7). We investigated the interaction between plasma AR and treatment type after incorporating updated data from our prior study of 73 chemotherapy-naïve, abiraterone/enzalutamide-treated patients, with data from 115 first-line docetaxel patients. In an exploratory analysis of mCRPC patients receiving first-line therapies, a significant interaction was observed between plasma AR and docetaxel versus abiraterone/enzalutamide for OS (HR=0.16, 95% CI=0.06-0.46, p<0.001) and PFS (HR=0.31, 95% CI=0.12-0.80, p=0.02). Specifically, we reported a significant difference for OS favoring abiraterone/enzalutamide for AR-normal patients (HR=1.93, 95% CI=1.19-3.12, p=0.008) and a suggestion favoring docetaxel for AR-gained patients (HR=0.53, 95% CI=0.24-1.16, p=0.11). These data suggest that AR-normal patients should receive abiraterone/enzalutamide and AR-gained could benefit from docetaxel. This treatment selection merits prospective evaluation in a randomized trial. PATIENT SUMMARY: We investigated whether plasma androgen receptor (AR) predicted outcome in metastatic castration-resistant prostate cancer (mCRPC) patients treated with docetaxel, and we performed an exploratory analysis in patients treated with docetaxel or AR-directed drugs as first-line mCRPC therapy. We showed that plasma AR normal favored hormonal treatment, whilst plasma AR-gained patients may have had a longer response to docetaxel, suggesting that plasma AR status could be a useful treatment selection biomarker.

Plasma AR status and cabazitaxel in heavily-treated metastatic castration-resistant prostate cancer (mCRPC)

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Background: Plasma androgen receptor ( AR) copy number status has been identified as a potential biomarker of response in mCRPC patients receiving docetaxel or the AR-targeted therapies abiraterone or enzalutamide. However, the relevance of plasma AR status in the context of cabazitaxel therapy is unknown. Methods: Between September 2011 and January 2018, pre-therapy plasma samples were collected from 155 patients treated with second or third-line cabazitaxel at standard or reduced dose in different biomarker protocols. Droplet digital PCR was used to identify plasma AR gain and normal samples, with the primary objective to evaluate associations of plasma AR status with treatment outcome. In an exploratory analysis, a comparison between plasma AR status and treatment type was investigated by incorporating updated data from our prior study of 85 post-docetaxel patients receiving abiraterone or enzalutamide. Results: We observed a shorter median overall/progression-free survival (OS/PFS) in AR-gained compared to AR-normal patients (OS 10.5 versus 14.1 months, hazard ratio (HR) 1.44, 95% confidence interval (CI) 0.98-2.13, P = 0.064), and (PFS 4.0 versus 5.0 months, HR 1.47, 95%CI 1.05-2.07, P = 0.024). In mCRPC patients receiving second-line therapies, a significant treatment interaction was observed between plasma AR and cabazitaxel versus AR-directed therapies for OS (P = 0.041) but not PFS (P = 0.244). In an exploratory analysis, AR-gained patients treated with initial reduced-dose of cabazitaxel had a significantly shorter median OS (7.3 versus 11.5 months, HR 1.95, 95%CI 1.13-3.38, P = 0.016), and PFS (2.7 versus 5.0 months, HR 2.27, 95%CI 1.39-3.71, P = 0.001). Conclusions: Plasma AR status has a potential clinical utility in patients being considered for cabazitaxel. Validation of these findings in prospective trials are warranted.

PROREPAIR-B: A Prospective Cohort Study of the Impact of Germline DNA Repair Mutations on the Outcomes of Patients With Metastatic Castration-Resistant Prostate Cancer

PURPOSE

Germline mutations in DNA damage repair (DDR) genes are identified in a significant proportion of patients with metastatic prostate cancer, but the clinical implications of these genes remain unclear. This prospective multicenter cohort study evaluated the prevalence and effect of germline DDR (gDDR) mutations on metastatic castration-resistance prostate cancer (mCRPC) outcomes.

PATIENTS AND METHODS

Unselected patients were enrolled at diagnosis of mCRPC and were screened for gDDR mutations in 107 genes. The primary aim was to assess the impact of ATM/BRCA1/BRCA2/ PALB2 germline mutations on cause-specific survival (CSS) from diagnosis of mCRPC. Secondary aims included the association of gDDR subgroups with response outcomes for mCRPC treatments. Combined progression-free survival from the first systemic therapy (PFS) until progression on the second systemic therapy (PFS2) was also explored.

RESULTS

We identified 68 carriers (16.2%) of 419 eligible patients, including 14 with BRCA2, eight with ATM, four with BRCA1, and none with PALB2 mutations. The study did not reach its primary end point, because the difference in CSS between ATM/BRCA1/BRCA2/PALB2 carriers and noncarriers was not statistically significant (23.3 v 33.2 months; P = .264). CSS was halved in germline BRCA2 (g BRCA2) carriers (17.4 v 33.2 months; P = .027), and g BRCA2 mutations were identified as an independent prognostic factor for CCS (hazard ratio [HR], 2.11; P = .033). Significant interactions between g BRCA2 status and treatment type (androgen signaling inhibitor v taxane therapy) were observed (CSS adjusted P = .014; PFS2 adjusted P = .005). CSS (24.0 v 17.0 months) and PFS2 (18.9 v 8.6 months) were greater in g BRCA2 carriers treated in first line with abiraterone or enzalutamide compared with taxanes. Clinical outcomes did not differ by treatment type in noncarriers.

CONCLUSION

g BRCA2 mutations have a deleterious impact on mCRPC outcomes that may be affected by the first line of treatment used. Determination of g BRCA2 status may be of assistance for the selection of the initial treatment in mCRPC. Nonetheless, confirmatory studies are required before these results can support a change in clinical practice.

Angiogenic role of miR-20a in breast cancer

Background

Angiogenesis is a key process for tumor progression and a target for treatment. However, the regulation of breast cancer angiogenesis and its relevance for clinical resistance to antiangiogenic drugs is still incompletely understood. Recent developments on the contribution of microRNA to tumor angiogenesis and on the oncogenic effects of miR-17-92, a miRNA cluster, point to their potential role on breast cancer angiogenesis. The aim of this work was to establish the contribution of miR-20a, a member of miR-17-92 cluster, to tumor angiogenesis in patients with invasive breast carcinoma.

Methods

Tube-formation in vitro assays with conditioned medium from MCF7 and MDA-MB-231 breast cancer cell lines were performed after transfection with miR-20a and anti-miR20a. For clinical validation of the experimental findings, we performed a retrospective analysis of a series of consecutive breast cancer patients (n = 108) treated with neoadjuvant chemotherapy and with a full characterization of their vessel pattern and expression of angiogenic markers in pre-treatment biopsies. Expression of members of the cluster miR-17-92 and of angiogenic markers was determined by RT-qPCR after RNA purification from FFPE samples.

Results

In vitro angiogenesis assays with endothelial cells and conditioned media from breast cancer cell lines showed that transfection with anti-miR20a in MDA-MB-231 significantly decreased mean mesh size and total mesh area, while transfection with miR-20a in MCF7 cells increased mean mesh size. MiR-20a angiogenic effects were abrogated by treatment with aflibercept, a VEGF trap. These results were supported by clinical data showing that mir-20a expression was higher in tumors with no estrogen receptor or with more extensive nodal involvement (cN2-3). A higher miR-20a expression was associated with higher mean vessel size (p = 0.015) and with an angiogenic pattern consisting in larger vessels, higher VEGFA expression and presence of glomeruloid microvascular proliferations (p<0.001). This association was independent of tumor subtype and VEGFA expression.

Conclusions

Transfection of breast cancer cells with miR-20a induces vascular changes in endothelial tube-formation assays. Expression of miR-20a in breast invasive carcinomas is associated with a distinctive angiogenic pattern consisting in large vessels, anomalous glomeruloid microvascular proliferations and high VEGFA expression. Our results suggest a role for miR-20a in the regulation of breast cancer angiogenesis, and raise the possibility of its use as an angiogenic biomarker.

An aberrant SREBP-dependent lipogenic program promotes metastatic prostate cancer

Lipids, either endogenously synthesized or exogenous, have been linked to human cancer. Here we found that PML is frequently co-deleted with PTEN in metastatic human prostate cancer (CaP). We demonstrated that conditional inactivation of Pml in the mouse prostate morphs indolent Pten-null tumors into lethal metastatic disease. We identified MAPK reactivation, subsequent hyperactivation of an aberrant SREBP prometastatic lipogenic program, and a distinctive lipidomic profile as key characteristic features of metastatic Pml and Pten double-null CaP. Furthermore, targeting SREBP in vivo by fatostatin blocked both tumor growth and distant metastasis. Importantly, a high-fat diet (HFD) induced lipid accumulation in prostate tumors and was sufficient to drive metastasis in a nonmetastatic Pten-null mouse model of CaP, and an SREBP signature was highly enriched in metastatic human CaP. Thus, our findings uncover a prometastatic lipogenic program and lend direct genetic and experimental support to the notion that a Western HFD can promote metastasis.

Androgen receptor gene status in plasma DNA associates with worse outcome on enzalutamide or abiraterone for castration-resistant prostate cancer: a multi-institution correlative biomarker study

BACKGROUND

There is an urgent need to identify biomarkers to guide personalized therapy in castration-resistant prostate cancer (CRPC). We aimed to clinically qualify androgen receptor (AR) gene status measurement in plasma DNA using multiplex droplet digital PCR (ddPCR) in pre- and post-chemotherapy CRPC.

METHODS

We optimized ddPCR assays for AR copy number and mutations and retrospectively analyzed plasma DNA from patients recruited to one of the three biomarker protocols with prospectively collected clinical data. We evaluated associations between plasma AR and overall survival (OS) and progression-free survival (PFS) in 73 chemotherapy-naïve and 98 post-docetaxel CRPC patients treated with enzalutamide or abiraterone (Primary cohort) and 94 chemotherapy-naïve patients treated with enzalutamide (Secondary cohort; PREMIERE trial).

RESULTS

In the primary cohort, AR gain was observed in 10 (14%) chemotherapy-naïve and 33 (34%) post-docetaxel patients and associated with worse OS [hazard ratio (HR), 3.98; 95% CI 1.74-9.10; P < 0.001 and HR 3.81; 95% CI 2.28-6.37; P < 0.001, respectively], PFS (HR 2.18; 95% CI 1.08-4.39; P = 0.03, and HR 1.95; 95% CI 1.23-3.11; P = 0.01, respectively) and rate of PSA decline ≥50% [odds ratio (OR), 4.7; 95% CI 1.17-19.17; P = 0.035 and OR, 5.0; 95% CI 1.70-14.91; P = 0.003, respectively]. AR mutations [2105T>A (p.L702H) and 2632A>G (p.T878A)] were observed in eight (11%) post-docetaxel but no chemotherapy-naïve abiraterone-treated patients and were also associated with worse OS (HR 3.26; 95% CI 1.47-not reached; P = 0.004). There was no interaction between AR and docetaxel status (P = 0.83 for OS, P = 0.99 for PFS). In the PREMIERE trial, 11 patients (12%) with AR gain had worse PSA-PFS (sPFS) (HR 4.33; 95% CI 1.94-9.68; P < 0.001), radiographic-PFS (rPFS) (HR 8.06; 95% CI 3.26-19.93; P < 0.001) and OS (HR 11.08; 95% CI 2.16-56.95; P = 0.004). Plasma AR was an independent predictor of outcome on multivariable analyses in both cohorts.

CONCLUSION

Plasma AR status assessment using ddPCR identifies CRPC with worse outcome to enzalutamide or abiraterone. Prospective evaluation of treatment decisions based on plasma AR is now required.

CLINICAL TRIAL NUMBER

NCT02288936 (PREMIERE trial).

Circulating miR-200c-3p as a marker of metastatic disease at diagnosis in breast cancer patients

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Background: MicroRNAs are involved in cancer biology through their role in regulation of protein expression. The miR-200 family plays a dual role in breast cancer (BC), both regulating epithelial to mesenchymal transition and promoting metastatic colonization. Plasma levels of miR-200 have been previously evaluated as prognostic factors in early and metastatic BC (MBC) but its role as a potential diagnostic marker is less well established. The aim of this study was to determine the potential diagnostic value of miR-200c-3p plasmatic levels in women with locally advanced and metastatic BC. Methods: We included 73 BC patients and 14 controls. Plasma samples were obtained at diagnosis, before treatment. RNA from plasma samples was extracted with NucleoSpin miRNA plasma (Macherey-Nagel). We analyzed expression levels of miR-200c-3p, which were relativized (2-ΔΔCT method) to miR-16. Non-parametric statistical tests were used to determine the association of miR-200c levels with clinical variables. Receiver-operating curves (ROC) were constructed and diagnostic ability evaluated. Kaplan-Meier curves and Cox models were used for survival analyses. Results: 73 BC patients were included: 36 locally advanced BC (LABC) and 37 MBC (7 recurrences and 30 MBC at initial diagnosis [MBCID]). Plasma miR-200c levels were significantly higher in MBC than in controls (p = 0.001) and in LABC (p = 0.001). We found differences neither for age nor for estrogen receptors, HER2, tumor subtype or histology. Overall and disease free survival did not differ by miR-200c levels in any of the groups. Among MBC patients, higher levels were observed in MBCID (p = 0.023). In the group of women with an initial diagnosis of BC (n = 65), high miR-200c levels (over 1st tertile) identified metastatic disease with a sensitivity of 90.0% (95%CI: 72.3-97.4%) and a specificity of 51.4% (95%CI: 34.3-68.3%); negative predictive value: 85.7%; positive predictive value: 61.4%; ROC AUC: 0.79. Conclusions: MiR-200c plasma levels are higher in BC patients with metastatic disease at diagnosis, and might be clinically useful to identify them. Further research on miR200c biological role in MBC and validation in larger populations with sequential samples are warranted.

Association of androgen receptor (AR) gene status in plasma DNA with outcome on enzalutamide in chemotherapy-naive metastatic castration-resistant prostate cancer (mCRPC): Exploratory results from the PREMIERE trial—On behalf of SOGUG

5016

Background: Building on previous discoveries studying AR status in plasma (Carreira S, Sci Transl Med 2014, Romanel A, Sci Transl Med 2015) and following a road-map for biomarker development, we aimed to clinically qualify AR status in chemotherapy-naïve mCRPC using an optimized multiplex droplet digital PCR (ddPCR) assay (Condeduca et al.;ASCO2017;Abstract#). Methods: Between February and November 2015, 98 asymptomatic or oligo-symptomatic chemotherapy-naïve mCRPC patients were recruited in 16 Spanish hospitals. Tissue and blood samples were required at study entry. Although initially designed to study the predictive value of TMPRSS2-ETS, data emerging after the trial was initiated led the group to prioritize alternative predefined exploratory biomarkers, including plasma ARand CTC characterization (Grande E. ESMO 2016 & Font A. et al; ASCO2017; Abstract #). Outcome measures included PSA-progression-free survival (sPFS), radiographic progression-free survival (rPFS) and overall survival (OS). Cox regression was used for survival analyses and Fisher’s exact test for PSA response. Results: Ninety-four patients had plasma DNA available for analysis. At baseline, AR gain was present in 11 pts (12%) and CTCs in 35 (37%). AR gain in CTC-positive and negative patients was 20% and 7%, respectively. At first interim analysis and with a median follow-up of 10.6 months, detection of AR gain was associated with worse sPFS (median, 3.60 versus 15.5 m, HR, 4.33; 95% CI 1.94-9.68; P < 0.001), rPFS (median, 3.90 m versus not reached HR, 8.06; 95% CI, 3.26-19.93; P < 0.001) and OS (medians not reached, HR, 11.08; 95% CI, 2.16-56.95; P = 0.004). These results were independently associated in multivariate analysis including cfDNA and CTCs for all described endpoints. AR gain patients were less likely to have a ≥50% decline in PSA (OR, 4.93; 95% CI, 1.30-18.75; P = 0.025). Conclusions: Detection of AR gain in plasma using a robust multiplex ddPCR method predicts an adverse outcome in chemotherapy-naïve mCRPC. Further prospective randomized studies are warranted. Clinical trial information: NCT02288936.

A randomized phase II/III study of cabazitaxel versus vinflunine in metastatic or locally advanced transitional cell carcinoma of the urothelium (SECAVIN)

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Background: Despite the advent of immunotherapy in urothelial cancer, there is still a need to find effective cytotoxic agents beyond first line. Vinflunine is EMA approved and used in several European countries. Docetaxel is widely used in second line. Cabazitaxel is a taxane with clinical activity in docetaxel-refractory cancers. A randomised study was conducted to compare its efficacy vs vinflunine. Methods: This was a multicenter, randomised, open-label, phase II/III study, following a Simon’s optimal method with early stopping rules based on an interim futility analysis. The study (NCT01830231) was supported by a research grant from Sanofi. The trial was aiming at superiority of cabazitaxel compared to vinflunine in patients progressing to platinum. ECOG, anemia and liver metastases were stratification factors. The primary objective for the phase II study was overall response rate (ORR), and overall survival (OS) for the phase III. Secondary objectives included safety and progression free survival (PFS). Results: 70 patients were included in the phase II across 19 institutions in Europe. Baseline characteristics were well balanced between the two arms. Mean age 63 years; 56 (80%) were men. No statistically significant differences were detected between arms for ORR (p=0.26). Three patients (13%) obtained a partial response on cabazitazel (95% CI, 2.7–32.4) and six patients (30%) in the vinflunine arm (95% CI, 11.9–54.3). Median PFS for cabazitaxel was 1.9 months versus 2.9 months for vinflunine (p=0.039). The study did not proceed to phase III since the futility analysis showed a lack of efficacy of cabazitaxel. A trend for OS benefit was found favouring vinflunine (median 7.6 versus 5.5 months). Grade 3-4 related adverse events were seen in 41% patients with no difference between arms. The most frequent toxicities associated with cabazitaxel were asthenia, diarrhea, anemia and febrile neutropenia. Conclusions: This phase II/III second line bladder trial comparing cabazitaxel with vinflunine was closed early when the phase II showed a lack of efficacy of the cabazitaxel arm. Vinflunine results were consistent with those observed in the phase III. Clinical trial information: NCT01830231.

Prognostic Significance of Venous Thromboembolic Events in Disseminated Germ Cell Cancer Patients

Background

Disseminated germ cell cancers are at high risk of developing thromboembolic complications. We evaluated the prognostic value of venous thromboembolic events (VTE) in disseminated germ cell cancer.

Methods

Patients with germ cell cancer receiving upfront platinum-containing chemotherapy between 2004 and 2014 were pooled from the Spanish Germ Cell Cancer Group (SGCCG) registry and reviewed for the presence of VTE. Results were validated in an independent international group of patients. We used a penalized Cox proportional hazards model including VTE as a time-varying covariate to identify and validate prognostic factors. All statistical tests were two-sided.

Results

The SGCCG registry identified 416 patients from 14 referral institutions. With a median follow-up of 49 months, VTEs were observed in 9% of patients (n = 38). Events occurred at diagnosis, during chemotherapy, and after chemotherapy in 2.6%, 5.0%, and 1.4% of patients, respectively. VTE was associated with shorter progression-free survival (PFS; hazard ratio [HR] = 2.29, 95% confidence interval [CI] = 1.18 to 4.47, P = .02) and overall survival (OS; HR = 5.14, 95% CI = 2.22 to 11.88, P < .001). In multivariable analysis, the effect was consistent in the intermediate-risk group, both for PFS (HR = 9.52 95% CI = 2.48 to 36.58, P < .001) and OS (HR = 12.84, 95% CI = 2.01 to 82.02, P = .007). VTE at diagnosis is also an adverse prognostic variable for progression-free survival (HR = 4.64, 95% CI = 2.04 to 10.54, P < .001) and for overall survival (HR = 6.28, 95% CI = 1.68 to 17.10, P = .01). These results were validated in an independent international cohort that included 241 patients from four hospitals.

Conclusions

VTE is an independent adverse prognostic factor in disseminated germ cell cancers, in particular for the intermediate prognostic group of the International Germ Cell Cancer Collaborative Group classification. The presence of VTE at diagnosis has also prognostic significance and should be further explored in future prognostic classifications.

Strategies to design clinical studies to identify predictive biomarkers in cancer research

The discovery of reliable biomarkers to predict efficacy and toxicity of anticancer drugs remains one of the key challenges in cancer research. Despite its relevance, no efficient study designs to identify promising candidate biomarkers have been established. This has led to the proliferation of a myriad of exploratory studies using dissimilar strategies, most of which fail to identify any promising targets and are seldom validated. The lack of a proper methodology also determines that many anti-cancer drugs are developed below their potential, due to failure to identify predictive biomarkers. While some drugs will be systematically administered to many patients who will not benefit from them, leading to unnecessary toxicities and costs, others will never reach registration due to our inability to identify the specific patient population in which they are active. Despite these drawbacks, a limited number of outstanding predictive biomarkers have been successfully identified and validated, and have changed the standard practice of oncology. In this manuscript, a multidisciplinary panel reviews how those key biomarkers were identified and, based on those experiences, proposes a methodological framework-the DESIGN guidelines-to standardize the clinical design of biomarker identification studies and to develop future research in this pivotal field.

Novel agents’ sequencing following first-line docetaxel in mCRPC patients: CAPRO study

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Background: Novel agents, such as abiraterone (A), cabazitaxel (CZ), and enzalutamide are currently available for the treatment of docetaxel (D)-treated metastatic castration resistant prostate cancer (mCRPC). The sequencing approach following D progression is still unknown. We now explore which factors are driving sequencing decisions in routine clinical practice in Spain. Methods: A prospective multicenter national observational descriptive study collecting data of 2nd line (L) treatments in mCRPC patients to analyze responses and progression to 1stL D. Results: 149 patients have been recruited from July 2013 to January 2015. Median age was 72 (48-89). Median D cycles was 6 (1-24), and median dose: 75 mg/m2 (30-75). 24 patients (16%) required dose reduction. The reasons for D ending were treatment completion (40%, n = 60), toxicity (15.3%, n = 23), progression (radiological, biochemical, clinical; 42%, n = 63), or others (2.7%, n = 4). 67% (n = 100) of the patients received A, 25% (n = 44) CZ, and 8% (n = 5) other treatments as 2ndL. From those who completed or progressed to D (n = 123), 2ndL initiation was mainly determined by two progression criteria (2C; biological and radiological), followed by one progression criteria (1C). This was independent of the 2ndL treatment chosen, and it was observed in similar ratios in both A (2C: 50%, n = 39; 1C: 37.2%, n = 29) and CZ (2C: 62.5%, n = 25; 1C: 27.5%, n = 11). Nevertheless, A was predominantly given when patients progressed after D ending, whereas CZ was mostly given when progressing during D (Table 1). Conclusions: A is the 2ndL treatment of choice in routine clinical practice in Spain, independent of the type and time of progression. CZ is preferentially used in patients progressing during D treatment. [Table: see text]

Abstract P5-01-08: Changes induced by neoadjuvant chemotherapy (NCT) in breast cancer tumor infiltrating lymphocytes (TIL) subpopulations are associated with chemo-sensitivity and prognosis

Background: Recent data support the modulation of immune response in breast cancer microenvironment by neoadjuvant chemotherapy. This immune modulation might favor treatment response and modify post-treatment tumor immunosurveillance. The association of TIL with outcome after breast cancer (BC) NCT has also been suggested by several studies. Thereby, the differences in NCT-induced immune changes could reflect different profiles of immune modulation and translate into diverse prognosis. The objective of our study was to evaluate the predictive and prognostic value of NCT-induced TIL changes in patients with BC.

Methods: We analyzed a series of consecutive breast cancer patients treated with sequential anthracyclines and taxanes NCT (80.4% sequential AC-docetaxel). Pre- and post-chemotherapy biopsies were included in a tissue microarray and immunohistochemical (IHC) staining was performed for CD3, CD4, CD8, CD20, FOXP3 and CD68. After slide scanning and acquisition of digital images, computerized morphometric analysis (TIL count/mm2) was performed with ImageJ (NIH) software. Variations on pre- and post-NCT TIL infiltration were quantified and expressed as the absolute difference in number of cells/mm2 (postNCT TIL – preNCT TIL); median values were used as cut-point. Association of TIL changes with pCR was evaluated by logistic regression models. Kaplan-Meier analysis and Cox proportional hazard models were used for survival

Results: 121 patients with a diagnosis of invasive BC were included. Stages: IIB (28%), IIIA-C (56.4%). Phenotype was determined by immunohistochemistry: 50.4% Her2- hormone-sensitive (HS), 13.2% Her2+ HS, 10.7% Her2+ non-HS, and 21.5% triple negative. Pathologic complete response (pCR) rate was 17.4%. NCT produced a decrease in tumor infiltration by CD4 (p = 0.01), CD20 (p = 0.04) and CD68 (p = 0.03) and an increase in CD8 infiltrating lymphocytes (p = 0.0001). NCT-induced decreases of TIL infiltration above the median level of change were associated with pCR: CD3 (p = 0.01; odds ratio [OR]: 0.12, 95% confidence interval [95%CI] 0.02-0.63), CD4 (p = 0.02; OR 0.2; 95%CI 0.05-0.85) and CD20 (p = 0.01; OR 0.15; 95%CI 0.03-0.64). With a median follow-up of 60 months, median overall survival (OS) and disease free survival (DFS) has not been reached. A NCT-induced CD3 decrease higher than the median cut-off independently predicted higher DFS (hazard ratio [HR]:6.56; 95%CI 1.3-33.2; p = 0,02) and OS (HR:9.85; 95%CI 1.03-93.7, p = 0.04).

Conclusions: TIL variations induced by chemotherapy are related to pRC and prognosis in patients with invasive BC receiving anthracyclines and taxanes. These results suggest that the degree of immune modulation by NCT has an impact on survival and might be useful for prognostic classification in the setting of BC treated with NCT [Supported by GEICAM-Beca Ana Balil].

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-01-08.

Zbtb7a suppresses prostate cancer through repression of a Sox9-dependent pathway for cellular senescence bypass and tumor invasion

Lrf has been previously described as a powerful proto-oncogene. Here we surprisingly demonstrate that Lrf plays a critical oncosuppressive role in the prostate. Prostate specific inactivation of Lrf leads to a dramatic acceleration of Pten-loss-driven prostate tumorigenesis through a bypass of Pten-loss-induced senescence (PICS). We show that LRF physically interacts with and functionally antagonizes SOX9 transcriptional activity on key target genes such as MIA, which is involved in tumor cell invasion, and H19, a long non-coding RNA precursor for an Rb-targeting miRNA. Inactivation of Lrf in vivo leads to Rb down-regulation, PICS bypass and invasive prostate cancer. Importantly, we found that LRF is genetically lost, as well as down-regulated at both the mRNA and protein levels in a subset of human advanced prostate cancers. Thus, we identify LRF as a context-dependent cancer gene that can act as an oncogene in some contexts but also displays oncosuppressive-like activity in Pten^−/− tumors.

Comparing diagnosis, management, and outcomes of synchronous versus metacrhonus brain metastases from testicular germ cell tumors (TGCT): Multinstitutional experience from the Spanish Germ Cell Cancer Group (SGCCG)

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Background: Metastases of testicular germ cell tumors (TGCT) to brain are a rare event. Prognostic is poor and there is little evidence on optimal management of these patients. Methods: A retrospective review of case records of germ cell tumor patients within the Spanish Germ Cell Cancer Group from 1994 to 2012 was conducted. Results: Thirty-tree cases of testicular germ cell tumors from 17 institutions were reported. Nineteen patients (57%) presented with brain metastases at primary diagnosis (group 1: synchronous), thirteen (40%) developed brain metastases at relapse (group 2: metachronous) and only one patient developed brain metastasis during cisplatin based-chemotherapy (3%) (excluded from the analysis). Main demographics and comparison between series are shown on table. Median serum BHCG levels at initial diagnosis were higher in group 1(279.083 versus 175.873), whereas those of AFP were higher in group 2(1320 versus 4181). The most common histology in the primary tumor was choriocarcinoma for group; versus embryonal carcinoma for group 2. Patients had neurological symptoms at diagnosis of brain metastases (63% synchronic/93% metachronus). Performance status was also poor (PS 2-3: 52,6%group 1-62,2% group 2). Four patients (21%) in group 1 had a solitary brain lesion vs seven (54%) on group 2. Median time since last dose of cisplatin to development of brain metastases on group 2 was 6 months (3-22).Median overall survival was 16 months (95% CI 5,3-26,6): group 1: 16 (95% CI 13,9-18);23 group 2 (95% CI 0-165). We have not found significant differences in survival between both groups. Overall 37,5% of patients achieved long-term survival (38,9% in group 1 versus 38,5% in group 2). Patients achieving complete response of brain metastases had a better survival (log rank p:0,003). Conclusions: Long term survival can be achieved in approximately 1/3 of patients with brain metastases. Chemotherapy remains the cornerstone of treatment. Selection bias because of the retrospective nature of review should make us be careful with the conclusions.

Circulating endothelial microparticles (EMP) modifications as predictive biomarkers of resistance to chemotherapy for breast cancer (BC)

3042

Background: Growing evidence indicates that EMP may both modulate angiogenesis and endothelial injury in cancer and cardiovascular disease. However, it has not been shown whether in vivo release of EMP might reflect the tumor response or the antiangiogenic effects of chemotherapy (CT). The aim of this work was to evaluate the relationship between the levels of small-size EMP (sEMP) and resistance to CT in locally advanced and metastatic BC. Methods: Citrated platelet-free plasma was obtained from BC patients before and after 3-4 cycles of chemotherapy. Small-size CD144+ sEMP (0.1-0.5 μm diameter) were prospectively quantified using a high resolution Apogee A50 flow cytometer. Association of EMP with clinical variables, response to CT and survival was analyzed. Response (partial or complete) was defined by RECIST criteria. Results: 45 BC patients were included (20, metastatic; 25, locally advanced). Treatment included anthracyclines in 66.7% of patients and taxanes in 15.5%. Small-size EMP baseline counts were higher in premenopausal women (p=0.008), but no association with other clinical or pathological characteristic was found. A significant decrease of circulating sEMP was observed after treatment with CT in the whole group of patients with paired samples available (n=33): pre-CT: 416.2 ± 365 vs. post-CT: 340.7 ± 458 (p=0.005). Lower chemotherapy-induced sEMP decrease was associated to treatment resistance: ROC analysis demonstrated a 66.7% sensitivity and 72.2% specificity of lower sEMP decrease for lack of response to CT using a decline cut-point of -40 sEMP (close to median decrease: -47). With the same cut-point of low sEMP decrease, odds ratio for treatment resistance was 5.2 (95% confidence interval, 1.17-23.04; p=0.03). No clear association of the degree of sEMP decrease was found for disease or progression free survival in the neoadjuvant or in the metastatic setting. Conclusions: This study suggests that circulating sEMP decrease after CT and are tightly associated with treatment resistance in BC patients. These findings indicate pathophysiological roles for sEMP in BC and support their potential role as treatment resistance biomarkers.

Predictive value of tumor infiltrating lymphocytes (TIL) for response to breast cancer neoadjuvant chemotherapy (NCT)

585

Background: The association of tumor microenvironment immune response with outcome after breast cancer (BC) NCT has been suggested by several studies. However, the relevance of each TIL subpopulation is still controversial. The objective of this study was to evaluate the predictive and prognostic value of TIL before and after NCT in patients with BC. Methods: We analyzed TIL and CD68 cells in pre- and post-chemotherapy biopsies of BC patients treated with NCT (80.4% sequential AC-docetaxel). A tissue microarray with paired pre- and post-NCT biopsies was built, and stained with immunohistochemistry (IHC) for CD3, CD4, CD8, CD20, FOXP3 and CD68. Morphometric analysis (TIL count/mm2) was performed after slide scanning and digitalization. Results: We included 121 consecutive patients with invasive BC, most of them with stages IIB (28%) or IIIA-C (56.4%). IHC phenotype: 50.4% Her2- hormone-sensitive (HS), 13.2% Her2+ HS, 10.7% Her2+ non-HS, and 21.5% triple negative. Pathologic complete response (pCR): 17.4%. Median overall survival (OS) and disease free survival (DFS) has not been reached (median follow-up: 60 months). Higher than median pre-NCT TIL infiltration was predictive of pCR to NCT: CD3 > 172/mm2 (p=0.001; Hazard Ratio [HR]: 9,61, 95% confidence interval [95%CI] 2.49–37.02); CD4 > 67/mm2 (p=0.001; HR: 8.82, 95%CI 2.43–31.96); CD20 > 42/mm2 (p=0.001; HR: 8.71, 95%CI 2.31–32.74). Logistic regression multivariate models including grade and IHC phenotype confirmed the independent predictive value of higher pre-NCT CD3, CD4, and CD20 for pCR. In the group of patients with HS Her2- BC without pCR (n=44), higher infiltration (cut-point: median value) by some TIL subpopulations and by CD68 cells in post-NCT residual tumor associated to lower DFS: CD8 > 37/mm2 (log-rank; p=0.04), CD20 > 14/mm2 (p=0.07) and CD68> 39/mm2 (p=0.06). Conclusions: Higher pre-treatment CD3, CD4 and CD20 TIL predicted pRC in patients with invasive BC receiving anthracyclines and taxanes NCT, while higher infiltration of residual tumor by CD8 associated to worse DFS in patients with HS Her2- BC without pCR after NCT. TIL might be useful as predictive factors in the setting of NCT for BC [Supported by GEICAM-Beca Ana Balil].

ABEL trial: A phase II randomized trial adding bemiparin (B) to chemo-radiotherapy (CT-RT) in limited-stage small cell lung cancer (SCLC)—Final results

7095

Background: Low molecular weight heparins (LMWH) could improve therapeutic outcomes in patients with advanced cancer. Heparin binding growth associated molecule is a member of growth factors involved in proliferation, angiogenesis and metastases in SCLC. LMWH associated with CT increase survival in cancer patients (Cochrane DB Systematic Reviews 2011). LMWH do not increase hemorrhagic events when used in neoplastic patients. Methods: Open randomized phase II multicentric trial to assess efficacy and safety of adding bemiparin to standard CT-RT in patients with SCLC with limited disease. CT: Cis/carboplatin + etoposide x 4-6 cycles. Concurrent early thoracic RT (45-50 Gy) and prophylactic cranial irradiation in case of response. Patients (p) were randomly allocated to addition of B at daily subcutaneous dose of 3.500 UI during 26 weeks. Primary end-point: progression free survival (PFS). Secondary end-points: response (RECIST), safety profile (CTC), venours thromboembolic (VTE) and hemorrhagic events incidence and overall survival (OS). Sample size 130 p. Preplanned interim analysis after inclusion 30 p. Results: From October-05 to January/10 39 p were included. Study was closed after interim analysis due to poor recruitment. 38 evaluable p. ITT analysis: 20 CR-RT + B vs 18 CT-RT. No significant disbalance in patient characteristics and prognostic factors. Median PFS 58.6 weeks (CT-RT+B) vs 38.8 w (CT-RT) (HR 2.576; Log-rank p=0,018). RR: 65% (CT-RT+B) vs 55% (CT-RT) (NS); Median OS 161.8 w (CT-RT+B) vs 49.3 w (CT-RT) (HR 2.96; Log-rank p=0,012). 2-year survival rate: 68.6% (CT-RT+B) vs 29.4% (CT-RT) (p=0,0042). Safety: G3-4 AE: 50% vs 67%; bleeding events: 10% vs 27% (NS); thrombocytopenia 15% vs 50% (p=0.024); VTE: 0 vs 22% (p=0.041). Conclusions: Addition of B (3.500 u/daily s.c. during 26 w) to CT-RT in SCLC with LD significantly increases PFS and OS. B does not increase hemorragic events and significantly reduces VTE. In spite of early closure of the trial due to poor accrual, these results warrants further research in this approach trying to improve current outcomes of SCLC. ClinicalTrials.gov Id: NCT00324558.

Long-term progression-free survival (PFS) and overall survival (OS) to pemetrexed (P) as single agent in metastatic urothelial carcinoma (MUC): A Spanish Oncology Genitourinary Group (SOGUG) systematic review

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Background: The effect of pemetrexed in MUC is not well characterized. Vinflunine is the standar second-line in MUC with adjusted benefits and no more drugs have been aproved. SOGUG reports a systematic review of MUC patient series with high activity of P in monotherapy. Methods: Patients with locally advanced urothelial carcinoma and/or MUC whom received P 500 mg/m(2) every 21 days with folic acid and vitamin B12 supplementation, were elected. These patients received P in second, third or fourth-line of chemotherapy. Results: 44 patients have been reported (39males), median age 62 [41-82]. Of all 44 patients; 21, 22, and 1 patients received P as second-line, third and fourth-line respectively. A median of 4 courses were administered [1-12] and disease control (SD+PR+CR) was achieved in 19 patients for an overall control rate of 43.2%. Four groups with significant differences in PFS (p=.033) were established (1.bone-metastasis, 2.visceral-metastasis, 3. nodal-visceral-metastasis and 4.nodal-metastasis). OS was significant between 2nd and 4th group (p=.036) . Mean PFS and OS were 125days [17-606] and 219days [17-1168] respectively for all 44 patients. Mean PFS and OS of 8 patients with bone metastasis were 75 days and 134 days. Mean PFS and OS of 10 patients with visceral metastasis were 65 days and 144 days. Mean PFS and OS of 8 patiens with nodal+visceral metastasis were 154 and 228 days. Mean PFS and OS of 18 patients with nodal metastasis were 166 days and 299 days. Conclusions: Our longer and multicenter follow-up shows that single agent P in monotherapy as second, third and fourth line in MUC is associated with high activity and long-time survival specially in metastatic nodal MUC. These results suggest that P as monotherapy requires to be further studied, more patients are being collected.

Prognostic value of decrease on blood lymphocytes in breast cancer patients undergoing primary chemotherapy

e11537

Background: There is evidence about chemotherapy creating a better tumor control by inmune system. Neoadjuvant treatment is an excellent situation to study tumor behaviour. The aim of this study is to determine whether decreases on blood lymphocytes (BL) absolute number have a prognostic significance on women with breast cancer receiving primary chemotherapy (PC). Methods: A retrospective analysis was performed of 105 breast cancer patients who underwent PC. Doxorubicin (60mg/m2q3w) - Cyclophosphamide (600mg/m2q3w) x4c followed docetaxel (100 mg/m2q3w) x4c was PC regimen in 73,4%. We collected data on BL before the first cycle of PC (basal BL), just before second doxorubicin- cyclophosphamide (AC) cycle (BLa), and three weeks from the end of PC (BLb). The median decrease (MD) in blood lymphocytes has been calculated: MDa = BLa - basal BL; MDb = BLb - basal BL. Results: Of 105 patients with breast cancer 16,2% were clinical stage IIA, 19% IIB, 30,5% IIIA, 14,3% IIIB, 15,2% IIIC. The mean age was 50 years. The complete pathologic response (pCR) rate was 14,9% in primary tumor, and 37,9% in axillary nodes. The median follow up is 25 months (mo). Overall survival: (OS) 25,3 mo (range 4 - 89.3). Disease-free survival: (DFS) 21,8 mo (range 5 - 80.3). The median decrease on blood lymphocytes is MDa=300 106/L(2400, -1000), MDb=700 106/L(3900, -400). A decrease on BL just before second AC cycle (> MDa=300 106/L) is correlated with worse DFS, in univariant and multivariant analysis (HR =4.022; 95% CI:1.105–14.63; p 0.035 at first; HR=5.36; 95% CI:1.1–25.82; p 0.037 at former). Patients with BL decrease three weeks after finishing PC (>MDb=700 106/L) have worse DFS in univariant as multivariant analysis (HR=5.9 95% CI:1.2–27.5; p0.022 at first; HR=9.7 95% CI:1.11- 85.07; p 0.04 at former). We have not found significant differences in OS. Conclusions: A decrease on blood lymphocyte number in women with breast cancer undergoing primary chemotherapy is correlated with worse DFS.

No significant financial relationships to disclose.

Predictive value for thrombosis of pre-chemotherapy D-Dimer in ambulatory cancer patients

e20601

Background: Elevated D-Dimer (DD) is related with activated coagulation system. We pretended to assess if high DD is predictive of thrombosis in ambulatory cancer patients. Methods: We prospectively determined DD in plasma specimens from ambulatory cancer patients, without previous thromboembolic events (TE), before chemotherapy initiation. DD was determined with an immunological test in an automated coagulometer (IL D-Dimer test, Instrumentations laboratory). The selected cut-off point for DD was 1.5 x UNL, as it was the nearest point to the median DD. All thromboembolic events were recorded. Results: Between June 2007 and December 2008 eighty four patients were included, 66% with advanced and 34% with early disease. The most frequent tumours were colorectal 31%, breast 27% and genitourinary cancers 30% (12% HR prostate and 28% non prostate cancers). Antiangiogenic drugs were included in 24% of treatments (16% Bevacizumab and 8% Sunitinib). Median ECOG was 1. With a median follow-up of 6.5 months, 12 thromboembolic events were observed (5 PE, 3 DVT and 4 Arterial thrombosis). The following variables were included in the univariate analysis: high DD (>1.5 x UNL), low haemoglobin (Hb <10 mg/dL), high leukocyte, high platelet, high BMI and tumour location. High DD (HR = 6,25, 95% CI: 1,34–29,25; p= 0,02) and low Hb (HR= 6,17, 95% CI: 1,77- 21,53; p=0,004) were associated with increased TE. The high risk group in the Khorana index was also significant (p=0.02). In multivariate analysis both high DD (HR= 5,06, 95%CI: 1,05–24,48; p=0,044) and low Hb (HR=3,77, 95%CI: 1,02–13,97; p=0,047) remained significant. Conclusions: High pre-chemotherapy DD is associated with increased risk of thrombosis in ambulatory cancer patients.

No significant financial relationships to disclose.

Impact of whole-body 18F-FDG PET on diagnostic and therapeutic management of Medical Oncology patients

AIM

Most studies evaluating positron-emission tomography (PET) impact on decision making are based on questionnaires sent to referring physicians, with low response rates and potential bias. Studies directly evaluating influence of PET on routine management of Medical Oncology patients are scarce.

PATIENTS AND METHODS

We retrospectively studied all patients evaluated by whole-body (18)F-FDG PET during 1 year in a Haematology/Oncology Department. We collected information regarding indication, PET results, modification of diagnostic and therapeutic management and adequacy of therapeutic changes.

RESULTS

One hundred consecutive patients having PET were evaluated. Diagnostic strategy was modified in 63% of patients (30% avoiding biopsy). Therapeutic management was modified by PET in 34% of cases: changes were classified as adequate in 30% and as inadequate in 4% of patients.

CONCLUSIONS

Our study shows a major impact of PET in the diagnostic and therapeutic management of cancer patients and supports its introduction as a routine diagnostic tool in Medical Oncology.