Search

Therapeutic options for metastatic prostate cancer patients are currently limited. In this issue of Cancer Cell , Kfoury et al. characterized the tumor and immune compartments of prostate cancer bone metastasis, revealing a mechanism of immunosuppression that involves infiltration with M2 macrophages and T cell exhaustion mediated by the CCL20-CCR6 axis. [ABSTRACT FROM AUTHOR]

Sipuleucel-T, a therapeutic dendritic-cell vaccine, was Food and Drug Administration-approved for prostate cancer in 2010. No new immunotherapies for prostate cancer have been approved since. However, novel agents and combination approaches offer great promise for improving outcomes for prostate cancer patients. Here we review the latest developments in immunotherapy for prostate cancer. Sipuleucel-T has demonstrated a survival advantage of 4.1 months in metastatic castration-resistant prostate cancer. PSA-TRICOM (PROSTVAC), a prostate-specific antigen-targeted vaccine platform, showed evidence of clinical and immunologic efficacy in early-phase clinical trials, and results from a phase III trial in advanced disease are pending. While immune checkpoint inhibitors appear to have modest activity as monotherapy, preclinical and clinical data suggest that they may synergize with vaccines, poly [ADP-ribose] polymerase inhibitors, and other agents. Several clinical studies that combine these therapies are underway. Combining prostate cancer vaccines with immune checkpoint inhibitors has great potential for improving clinical outcomes in prostate cancer. Such combination approaches may create and then recruit tumor-specific T cells to tumor while also increasing their effector function. Other emerging agents may also enhance immune-mediated tumor destruction. [ABSTRACT FROM AUTHOR]

Context Prostate cancer is the most common nonskin cancer and second most common cause of cancer mortality in US men. Androgen deprivation therapy (ADT), specifically surgical or medical castration, is the first line of treatment against advanced prostate cancer and is also used as an adjuvant to local treatment of high-risk disease. Objective To review systematically the evidence on the risks and benefits of ADT for prostate cancer as well as clinical management of its adverse effects. Evidence Acquisition We performed MEDLINE searches of English-language literature (1966 to March 2005) using the terms androgen deprivation therapy, hormone treatment, and prostate cancer. We reviewed bibliographies of literature to extract other relevant articles. Studies were selected based on clinical pertinence, with an emphasis on controlled study design. Evidence Synthesis Androgen deprivation therapy is effective for palliation in many patients with advanced prostate cancer and improves outcomes for high-risk patients treated with radiation therapy for localized disease. Although patients with increasing prostate-specific antigen levels after local treatment without metastatic disease frequently undergo ADT, the benefits of this strategy are not clear. Adverse effects of ADT include decreased libido, impotence, hot flashes, osteopenia with increased fracture risk, metabolic alterations, and changes in cognition and mood. Conclusions Androgen deprivation therapy has clear roles in the management of advanced prostate cancer and high-risk localized disease. The benefits of ADT in other settings need to be weighed carefully against substantial risks and adverse effects on quality of life. [ABSTRACT FROM AUTHOR]

An editorial is presented on the clinical trials with immune checkpoint inhibitors for finding the best possible treatment for prostate cancer. Topics discussed include inhospitability to immune cells which limits the potential of immunotherapy in prostate cancer, data analysis in gene expression to improve immunotherapy development and treatment of prostate cancer patient with ipilimumab.

Abstract: There are multiple new technologies being developed for imaging of advanced prostate cancer. This Seminar article highlights several of these emerging modalities that were discussed at the Society of Urologic Oncology annual meeting in Bethesda, MD. [Copyright &y& Elsevier]

Sipuleucel-T is an autologous cellular immunotherapy approved in the US for patients with asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC). This significant advance for mCRPC treatment provides healthcare professionals with another effective therapy to extend survival. As an immunotherapy, sipuleucel-T possesses specific characteristics differentiating it from traditional therapies. At a roundtable meeting of experts, sipuleucel-T data were discussed, focusing on interpretation and clinical implications. Important differences between immunotherapies and traditional therapies were explored, e.g., mode of action, outcomes, data consistency and robustness, timing of sipuleucel-T treatment, and future perspectives in areas such as short-term markers of long-term benefit. [ABSTRACT FROM AUTHOR]

A concurrent multicenter, randomized Phase II trial employing a recombinant poxviral vaccine provided evidence of enhanced median overall survival (OS) (p = 0.0061) in patients with metastatic castrate-resistant prostate cancer (mCRPC). The study reported here employed the identical vaccine in mCRPC to investigate the influence of GM-CSF with vaccine, and the influence of immunologic and prognostic factors on median OS. Thirty-two patients were vaccinated once with recombinant vaccinia containing the transgenes for prostate-specific antigen (PSA) and three costimulatory molecules. Patients received boosters with recombinant fowlpox containing the same four transgenes. Twelve of 32 patients showed declines in serum PSA post-vaccination and 2/12 showed decreases in index lesions. Median OS was 26.6 months (predicted median OS by the Halabi nomogram was 17.4 months). Patients with greater PSA-specific T-cell responses showed a trend (p = 0.055) toward enhanced survival. There was no difference in T-cell responses or survival in cohorts of patients receiving GM-CSF versus no GM-CSF. Patients with a Halabi predicted survival of <18 months (median predicted 12.3 months) had an actual median OS of 14.6 months, while those with a Halabi predicted survival of ≥18 months (median predicted survival 20.9 months) will meet or exceed 37.3 months, with 12/15 patients living longer than predicted (p = 0.035). Treg suppressive function was shown to decrease following vaccine in patients surviving longer than predicted, and increase in patients surviving less than predicted. This hypothesis-generating study provides evidence that patients with more indolent mCRPC (Halabi predicted survival ≥18 months) may best benefit from vaccine therapy. [ABSTRACT FROM AUTHOR]

Abstract: Novel strategies are emerging from preclinical and clinical investigations for combining vaccines with conventional and experimental anticancer therapies. Several lines of research show that combining either radiation or certain chemotherapeutic agents with vaccine can alter the phenotype of tumor cells, rendering them more susceptible to T cell-mediated killing. Furthermore, there is emerging data suggesting that an immune response elicited by vaccine may augment the antitumor effectiveness of subsequent therapies. This article reviews and discusses therapeutic cancer strategies that employ vaccines sequentially or in combination with conventional cytotoxic therapies such as local radiation, chemotherapy, and hormone therapy, or immunopotentiating therapies such as anti-CTLA-4 monoclonal antibodies. Preliminary results of clinical studies using these combination strategies have demonstrated a postvaccination antigen cascade, prolonged time to disease progression, and preliminary evidence of improved overall survival. Large randomized studies are currently underway to further investigate these findings. [Copyright &y& Elsevier]

Relationships between DNA-damage repair (DDR) mutations and anaplastic features, which confer poor prognosis, are unknown. Fifty-five patients with mCRPC treated with olaparib and durvalumab were classified into anaplastic and nonanaplastic groups and had similar rates of DDR mutations. Anaplastic patients had a trend toward improved progression-free survival when treated with olaparib and durvalumab compared with nonanaplastic patients. Background: Anaplastic prostate cancer has a poor prognosis with limited treatment options. Seven clinical features of anaplastic prostate cancer have been prospectively identified. In this phase II clinical trial, we identified mutations, including DNA damage repair (DDR) mutations, in patients with metastatic castration-resistant prostate cancer (mCRPC) who were treated with durvalumab and olaparib and determined how many of them can be described as anaplastic, and we examined the overlap between anaplastic features and DDR mutations. Methods: Eligible patients with mCRPC received prior enzalutamide, abiraterone, or both. Patients were treated with durvalumab 1500 mg i.v. every 28 days and olaparib 300 mg p.o. every 12 hours until disease progression or unacceptable toxicity. Patients underwent mandatory baseline biopsies of metastatic lesions. Results: Baseline characteristics were similar between anaplastic and nonanaplastic patients. Eleven patients (20%) displayed clear anaplastic features, and 43 (78.2%) lacked anaplastic features. In the anaplastic group, 2/11 (18.2%) had germline DRR mutations, and 4/11 (36.3%) had somatic DDR mutations. In the nonanaplastic group, 7/43 (16.3%) had germline mutations, and 13/43 (30.2%) had somatic mutations. Median progression-free survival (PFS) times in patients with anaplastic features (6.5 months) and without anaplastic features (5.1 months) were similar (hazard ratio 0.998, P = .996). Conclusions: Patients with and without anaplastic features appear to have similar total rates of DDR mutations and also similar rates of somatic and germline DDR mutations. Patients with anaplastic features have a trend toward improved PFS when treated with olaparib and durvalumab compared with nonanaplastic patients. [ABSTRACT FROM AUTHOR]

Patients diagnosed with high risk localized prostate cancer have variable outcomes following surgery. Trials of intense neoadjuvant androgen deprivation therapy (NADT) have shown lower rates of recurrence among patients with minimal residual disease after treatment. The molecular features that distinguish exceptional responders from poor responders are not known. To identify genomic and histologic features associated with treatment resistance at baseline. Targeted biopsies were obtained from 37 men with intermediate- to high-risk prostate cancer before receiving 6 mo of ADT plus enzalutamide. Biopsy tissues were used for whole-exome sequencing and immunohistochemistry (IHC). We assessed the relationship of molecular features with final pathologic response using a cutpoint of 0.05 cm3 for residual cancer burden to compare exceptional responders to incomplete and nonresponders. We assessed intratumoral heterogeneity at the tissue and genomic level, and compared the volume of residual disease to the Shannon diversity index for each tumor. We generated multivariate models of resistance based on three molecular features and one histologic feature, with and without multiparametric magnetic resonance imaging estimates of baseline tumor volume. Loss of chromosome 10q (containing PTEN) and alterations to TP53 were predictive of poor response, as were the expression of nuclear ERG on IHC and the presence of intraductal carcinoma of the prostate. Patients with incompletely and nonresponding tumors harbored greater tumor diversity as estimated via phylogenetic tree reconstruction from DNA sequencing and analysis of IHC staining. Our four-factor binary model (area under the receiver operating characteristic curve [AUC] 0.89) to predict poor response correlated with greater diversity in our cohort and a validation cohort of 57 Gleason score 8–10 prostate cancers from The Cancer Genome Atlas. When baseline tumor volume was added to the model, it distinguished poor response to NADT with an AUC of 0.98. Prospective use of this model requires further retrospective validation with biopsies from additional trials. A subset of prostate cancers exhibit greater histologic and genomic diversity at the time of diagnosis, and these localized tumors have greater fitness to resist therapy. Some prostate cancer tumors do not respond well to a hormonal treatment called androgen deprivation therapy (ADT). We used tumor volume and four other parameters to develop a model to identify tumors that will not respond well to ADT. Treatments other than ADT should be considered for these patients. A subset of patients present with high-risk localized prostate cancer that exhibits greater histologic and genomic diversity. These patients are less likely to respond to intense neoadjuvant androgen deprivation therapy. [ABSTRACT FROM AUTHOR]

Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies. [ABSTRACT FROM AUTHOR]

OBJECTIVE To identify patients with androgen-independent prostate cancer (AIPC) with bone metastasis and no soft-tissue metastases at the time of protocol enrolment, and analyse their disease progression by computed tomography (CT), bone scan, and prostate-specific antigen (PSA) level to determine the utility of routine interval CT in such patients. PATIENTS AND METHODS Bone is the most common metastatic site in patients with AIPC and the only site of metastatic disease for many; because some with initial bone metastasis eventually develop soft-tissue disease, many clinical trials use routine CT to monitor for the latter as a sign of disease progression, but the actual incidence of new soft-tissue metastases is unknown and the role of routine interval CT in monitoring for disease progression, especially for asymptomatic patients, is unclear. Thus we reviewed 175 cases of metastatic AIPC from three randomized phase II clinical trials (docetaxel/thalidomide, docetaxel/vaccine, and ketoconazole/alendronate) at the National Cancer Institute between 1995 and 2004. The patients’ PSA levels were assessed every 4 weeks, and CT and bone scans were done every 2–3 months. We retrospectively identified patients with bone metastasis only and examined subsequent CT for the occurrence of soft-tissue disease. For patients with progressive disease, we also examined bone scan and PSA progression. RESULTS Of 175 patients with metastatic prostate cancer, 105 (60%) had bone metastasis only, 12 (6.9%) had soft-tissue metastases only, and 58 (33.1%) had both bone and soft-tissue metastases. The median (range) follow-up was 8 (1–44) months for the 105 patients with bone metastasis only. During that time, two patients (1.9%) developed new soft-tissue disease; one developed right iliac fossa lymphadenopathy after 8 months and the other developed a perirectal mass after 12 months. The patient with new lymphadenopathy also had multiple new bone lesions identified by bone scan and PSA progression. The patient with the perirectal mass had PSA progression and a palpable abnormality. CONCLUSION This review of patients with AIPC and bone metastasis only, followed for a median of 8 months on clinical trials, shows that the incidence of asymptomatic new soft-tissue disease as the only sign of disease progression is quite low. Therefore, routine CT to exclude new soft-tissue disease in this population appears to be unwarranted. We recommend that for these patients CT is done only at the time of disease progression, as shown by bone scan, PSA level, or clinical presentation. We do not exclude the possibility that patients who remain on trial for significantly longer periods might benefit from routine interval CT. [ABSTRACT FROM AUTHOR]

Sipuleucel-T is an autologous cellular immunotherapy that induces an immune response targeted against prostatic acid phosphatase (PAP) to treat asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer. In the phase III IMPACT study, sipuleucel-T was associated with a statistically significantly increased overall survival (OS) (median = 4.1 months) vs placebo. Patients with baseline prostate-specific antigen levels in the lowest quartile (≤22.1 ng/mL) exhibited a 13-month improvement in OS with sipuleucel-T. Together, this led sipuleucel-T to be approved and recommended as first-line therapy in various guidelines for treatment of metastatic castration-resistant prostate cancer. This review discusses the varied findings about the mechanisms of action of sipuleucel-T, bringing them together to form a more coherent picture. These pieces include inducing a statistically significant increase in antigen-presenting cell activation; inducing a peripheral immune response specific to the target (PAP) and/or immunizing (PA2024) antigens; stimulating systemic cytotoxic T-lymphocyte activity; and mediating antigen spread (ie, increased antibody responses to secondary proteins in addition to PAP and PA2024). Each of these pieces individually correlates with OS. Sipuleucel-T also traffics T cells to the prostate and is associated with long-term immune memory such that a second course of treatment induces an anamnestic immune response. Prostate cancer does not have a strongly inflamed microenvironment, thus its response to immune checkpoint inhibitors is limited. Because sipuleucel-T is able to traffic T cells to the tumor, it may be an ideal combination partner with immunotherapies including immune checkpoint inhibitors or with radiation therapy. [ABSTRACT FROM AUTHOR]

PURPOSE: Despite decreased screening-based detection of clinically insignificant tumors, most diagnosed prostate cancers are still indolent, indicating a need for better strategies for detection of clinically significant disease before treatment. We hypothesized that patients with detectable circulating tumor DNA (ctDNA) were more likely to harbor aggressive disease. METHODS: We applied ultra-low-pass whole-genome sequencing to profile cell-free DNA from 112 patients diagnosed with localized prostate cancer and performed targeted resequencing of plasma DNA for somatic mutations previously identified in matched solid tumor in nine cases. We also performed similar analyses of data from patients with metastatic prostate cancer. RESULTS: In all cases of localized prostate cancer, even in clinically high-risk patients who subsequently had recurrent disease, ultra-low-pass whole-genome sequencing and targeted resequencing did not detect ctDNA in plasma acquired before surgery or before recurrence. In contrast, using both approaches, ctDNA was detected in patients with metastatic prostate cancer. CONCLUSION: Our findings demonstrate clear differences between localized and advanced prostate cancer with respect to the dissemination and detectability of ctDNA. Because allele-specific alterations in ctDNA are below the threshold for detection in localized prostate cancer, other approaches to identify cell-free nucleic acids of tumor origin may demonstrate better specificity for aggressive disease. [ABSTRACT FROM AUTHOR]

Prostate cancer is the most commonly diagnosed malignancy and second leading cause of cancer death among men in the United States. In recent years, several new agents, including cancer immunotherapies, have been approved or are currently being investigated in late-stage clinical trials for the management of advanced prostate cancer. Therefore, the Society for Immunotherapy of Cancer (SITC) convened a multidisciplinary panel, including physicians, nurses, and patient advocates, to develop consensus recommendations for the clinical application of immunotherapy for prostate cancer patients. To do so, a systematic literature search was performed to identify high-impact papers from 2006 until 2014 and was further supplemented with literature provided by the panel. Results from the consensus panel voting and discussion as well as the literature review were used to rate supporting evidence and generate recommendations for the use of immunotherapy in prostate cancer patients. Sipuleucel-T, an autologous dendritic cell vaccine, is the first and currently only immunotherapeutic agent approved for the clinical management of metastatic castrate resistant prostate cancer (mCRPC). The consensus panel utilized this model to discuss immunotherapy in the treatment of prostate cancer, issues related to patient selection, monitoring of patients during and post treatment, and sequence/combination with other anti-cancer treatments. Potential immunotherapies emerging from late-stage clinical trials are also discussed. As immunotherapy evolves as a therapeutic option for the treatment of prostate cancer, these recommendations will be updated accordingly. [ABSTRACT FROM AUTHOR]

Objective TRC105 is a chimeric immunoglobulin G1 monoclonal antibody that binds endoglin ( CD105). This phase I open-label study evaluated the safety, pharmacokinetics and pharmacodynamics of TRC105 in patients with metastatic castration-resistant prostate cancer ( mCRPC). Patients and Methods Patients with mCRPC received escalating doses of i.v. TRC105 until unacceptable toxicity or disease progression, up to a predetermined dose level, using a standard 3 + 3 phase I design. Results A total of 20 patients were treated. The top dose level studied, 20 mg/kg every 2 weeks, was the maximum tolerated dose. Common adverse effects included infusion-related reaction (90%), low grade headache (67%), anaemia (48%), epistaxis (43%) and fever (43%). Ten patients had stable disease on study and eight patients had declines in prostate specific antigen (PSA). Significant plasma CD105 reduction was observed at the higher dose levels. In an exploratory analysis, vascular endothelial growth factor ( VEGF) was increased after treatment with TRC105 and VEGF levels were associated with CD105 reduction. Conclusion TRC105 was tolerated at 20 mg/kg every other week with a safety profile distinct from that of VEGF inhibitors. A significant induction of plasma VEGF was associated with CD105 reduction, suggesting anti-angiogenic activity of TRC105. An exploratory analysis showed a tentative correlation between the reduction of CD105 and a decrease in PSA velocity, suggestive of potential activity of TRC105 in the patients with mCRPC. The data from this exploratory analysis suggest that rising VEGF level is a possible compensatory mechanism for TRC105-induced anti-angiogenic activity. [ABSTRACT FROM AUTHOR]

Background E9802 was a phase 2 multi-institution study conducted to evaluate the safety and effectiveness of vaccinia and fowlpox prostate-specific antigen (PSA) vaccine (step 1) followed by combination with androgen ablation therapy (step 2) in patients with PSA progression without visible metastasis. Objective To test the hypothesis that vaccine therapy in this early disease setting will be safe and have a biochemical effect that would support future studies of immunotherapy in patients with minimal disease burden. Design, setting, and participants Patients who had PSA progression following local therapy were treated with PROSTVAC-V (vaccinia)/TRICOM on cycle 1 followed by PROSTVAC-F (fowlpox)/TRICOM for subsequent cycles in combination with granulocyte-macrophage colony-stimulating factor (step 1). Androgen ablation was added on progression (step 2). Outcome measurements and statistical analysis Step 1 primary end points included progression at 6 mo and characterization of change in PSA velocity pretreatment to post-treatment. Step 2 end points included PSA response with combined vaccine and androgen ablation. Results and limitations In step 1, 25 of 40 eligible patients (63%) were progression free at 6 mo after registration (90% confidence interval [CI], 48–75). The median pretreatment PSA velocity was 0.13 log(PSA)/mo, in contrast to median postregistration velocity of 0.09 log(PSA)/mo ( p = 0.02), which is an increase in median PSA doubling time from 5.3 mo to 7.7 mo. No grade ≥4 treatment-related toxicity was observed. In the 27 patients eligible and treated for step 2, 20 patients achieved a complete response (CR) at 7 mo (CR rate: 74%; 90% CI, 57–87). Although supportive of larger studies in the cooperative group setting, this study is limited by the small number of patients and the absence of a control group as in a phase 3 study. Conclusions A viral PSA vaccine can be administered safely in the multi-institutional cooperative group setting to patients with minimal disease volume alone and combined with androgen ablation, supporting the feasibility of future phase 3 studies in this population. Patient summary These data support consideration of vaccine therapy earlier in the course of prostate cancer progression with minimal disease burden in future studies of vaccine approaches in earlier stages of disease. [ABSTRACT FROM AUTHOR]

Prostvac is a poxviral-based vaccine designed to target prostate-specific antigen (PSA) in prostate cancer patients. Recently, the potential toxicity and immunological impact of this immunotherapy were reviewed in the context of new clinical data. Our findings suggest that Prostvac is safe and elicits anticancer immune responses, both alone and in combinatorial approaches. [ABSTRACT FROM PUBLISHER]

Prostate cancer is the second leading cause of cancer death among men in the United States. Standard-of-care chemotherapy for metastatic castration-resistant prostate cancer is associated with significant but modest survival benefit, indicating a need for alternative and/or additional approaches. The use of therapeutic cancer vaccines for the treatment of prostate cancer represents a novel targeted therapeutic approach. Whereas vaccine strategies are being developed for the treatment of various stages of prostate cancer, this article focuses on novel vaccine strategies for castration-resistant prostate cancer that have been translated into late-stage clinical studies. [ABSTRACT FROM AUTHOR]

New gene expressed in prostate (NGEP) is a prostate-specific gene encoding either a small cytoplasmic protein (NGEP-S) or a larger polytopic membrane protein (NGEP-L). NGEP-L expression is detectable only in prostate cancer, benign prostatic hyperplasia and normal prostate. We have identified an HLA-A2 binding NGEP epitope (designated P703) which was used to generate T cell lines from several patients with localized and metastatic prostate cancer. These T cell lines were able to specifically lyse HLA-A2 and NGEP-expressing human tumor cells. NGEP-P703 tetramer binding assays demonstrated that metastatic prostate cancer patients had a higher frequency of NGEP-specific T cells when compared with healthy donors. Moreover, an increased frequency of NGEP-specific T cells was detected in the peripheral blood mononuclear cells of prostate cancer patients post-vaccination with a PSA-based vaccine, further indicating the immunogenicity of NGEP. These studies thus identify NGEP as a potential target for T cell-mediated immunotherapy of prostate cancer. [ABSTRACT FROM AUTHOR]

Objectives of this study were to determine the maximum tolerated dose and to characterize the side effect profile and pharmacokinetics of lenalidomide in patients with advanced refractory solid tumors. Patients were treated on a modified Fibronacci dose escalation scheme with an oral daily dose of lenalidomide. A total of 45 patients with 8 different tumor types were accrued. Doses administered included 5, 10, and 20 mg continuous daily doses, every 28 days (n = 15), later modified to intermittent doses of 15, 20, 25, 30, 35, and 40 mg, with a 21 days-on and 7 days-off schedule, due to observed side effects. Lenalidomide exhibited a linear pharmacokinetics over a wide range of doses with the mean half-life of 3.9 hours. The renal function affected lenalidomide clearance, resulting in 50% reduction in patients with mild renal impairment compared with patients with normal function (CL/F = 243 mL/ min). Stable disease was documented in 12 of 44 evaluable patients, of whom 9 patients had prostate cancer. Most frequent grade 1 and 2 toxicities included fatigue, nausea, pruritus/rash, neutropenia, and neuropathy. Grade 3/4 events were predominantly hematologic. Lenalidomide was well tolerated up to a 35-mg/d intermittent dosing schedule at doses higher than previously indicated for hematologic malignancies. [ABSTRACT FROM AUTHOR]

ONJ is an important toxicity in cancer patients receiving bisphosphonate therapy. Here we report a higher than usual incidence of ONJ, 11 of 60 (18.3%, 95% Confidence Interval, CI: 9%-28%) patients enrolled in a phase II clinical trial combining bevacizumab, docetaxel, thalidomide, and prednisone (ATTP) in chemotherapy-naive men with metastatic castration resistant prostate cancer (mCRPC). The use of bisphosphonates was allowed at study entry. Our study suggests that anti-angiogenic and chemotherapy agents can predispose to the development of ONJ in men with mCRPC on zoledronic acid. Imaging modalities, such as bone scans, may be useful in following the clinical course of patients who develop ONJ. [ABSTRACT FROM AUTHOR]

OBJECTIVE To determine if patients with advanced prostate cancer carrying a polymorphism that codes for a more active testosterone transporter have less durable responses to androgen-deprivation therapy (ADT) than patients not carrying this polymorphism. PATIENTS AND METHODS We previously determined that a polymorphism in SLCO1B3 affects testosterone transport and that those men who have at least one wild-type T allele at the 334 T > G polymorphism in this gene have a shorter survival. We hypothesized that the T allele which increases testosterone transport would be associated with a shorter interval from ADT to androgen independence. We examined the association between this SLCO1B3 polymorphism and time from ADT to androgen independence, ADT to prostate-specific antigen (PSA) nadir and PSA nadir to androgen independence in 68 Caucasian patients with advanced prostate cancer who were treated with ADT with metastatic disease (D2) or biochemical failure with no metastatic disease (D0). RESULTS When examined separately, patients in the individual stages tended to have a shorter time to androgen independence with the T allele in the D0 ( P = 0.11) and D2 ( P = 0.18) groups. Combining these groups and stratifying by stage yielded a statistically significant shorter time to androgen independence with the T allele ( P = 0.048). CONCLUSION A polymorphism in a transporter that increases testosterone import is associated with a shorter time to androgen independence in patients with prostate cancer who are treated with ADT. [ABSTRACT FROM AUTHOR]

OBJECTIVE To evaluate the combination of docetaxel plus estramustine (which prolongs survival in patients with androgen-independent prostate cancer, AIPC), and thalidomide (that also adds to docetaxel activity), both pre-clinically and clinically in AIPC. PATIENTS, MATERIALS AND METHODS In the pre-clinical evaluation we injected PC3 cells subcutaneously into severely combined immunodeficient mice and started treatment after the tumour volume reached 50 mm3. We also evaluated the combination using luciferase-labelled PC3M-luc-C6 cells in nude mice. We enrolled 20 patients with metastatic progressive AIPC into a phase II clinical trial to evaluate this combination. Docetaxel (30 mg/m2) was administered every week, for 3 of 4 weeks. The dose of thalidomide was 200 mg/day and estramustine was given three times a day at 1, 2, 3, 8, 9, 10, 15, 16 and 17 days. RESULTS In the mice, thalidomide with docetaxel plus estramustine reduced tumour volume by 88% at 17 days vs the control treatment ( p = 0.001). The combination of docetaxel, estramustine and thalidomide nearly eradicated the signal from the luciferase-expressing PC3M cells in the metastasis model. Clinically, the progression-free time was 7.2 months with this combination; 18 of 20 patients had a decline of half or more in prostate-specific antigen level and two of 10 patients with soft-tissue lesions had a partial response on computed tomography. There were 24 grade 3 and two grade 4 complications associated with this combination. There was a statistically significant association between overall survival and the CYP1B1*3 genotype ( P = 0.013). CONCLUSION Docetaxel-based chemotherapy is now regarded as a standard regimen for metastatic AIPC. The combination of estramustine, docetaxel and thalidomide is an advantageous treatment in pre-clinical models of prostate cancer and is a safe, tolerable and active regimen in patients with AIPC. [ABSTRACT FROM AUTHOR]

Authors from the National Cancer Institute present a study which assessed the time to androgen independence and overall survival for patients with metastatic prostate cancer. They reported a longer than expected survival with androgen-independent prostate cancer, and make original observations on the time to metastatic disease for patients with no evidence of radiographic disease. The new wave of chemotherapeutic agents for hormone-resistant prostate cancer has generated a new interest in producing more. Dr Cora Sternberg from Rome presents information on satraplatin, a third-generation orally available platinum analogue that shares more structural similarities with cisplatin. There are several other papers in this section on prostate bladder and renal cancer, and finally a paper from London on penile cancer, asking what surgical resection margins are required to achieve oncological control, and finding that the traditional 2 cm margin may be unnecessary, with excision margins of only a few millimetres needed to give excellent control. OBJECTIVE To determine the natural history of patients with prostate cancer who start initial androgen-deprivation therapy (ADT) for biochemical failure with no radiographic evidence of disease (D0) or with radiographic metastatic disease (D2), as the history is either not well-defined or is changing, and such data are critical for guiding therapy after prostate cancer recurrence. PATIENTS AND METHODS We retrospectively assessed the time to androgen-independence (AI), defined as the first sustained rise in prostate-specific antigen (PSA) level on ADT, time to metastatic disease and overall survival for 80 patients with metastatic prostate cancer in clinical trials at the National Cancer Institute. RESULTS ADT was initiated after metastatic disease in 37 patients and before metastatic disease in 43 patients; in these 43 patients, the median time to developing metastatic disease on ADT was 37.8 months. The median time to AI from the initiation of ADT was 19.3 and 13.1 months in D0 and D2 patients, respectively. The median overall survival from the start of ADT was 89.0 and 63.0 months, and the median overall survival from the time of AI was 63.1 and 44.2 months in D0 and D2 patients, respectively. These 80 patients, which included 43 who had no metastatic disease when starting ADT, had a median survival of 54.8 months after AI prostate cancer. CONCLUSIONS We describe the natural history of AI prostate cancer in D0 patients who eventually developed metastasis, and in D2 patients. The results suggest a longer than expected survival with AI prostate cancer, and to our knowledge this is the first study to report the time to metastatic disease for D0 patients from ADT and from AI. These results can be used to help design clinical trials in patients with D0 prostate cancer. [ABSTRACT FROM AUTHOR]

Introduction: Using multiparametric magnetic resonance imaging (mpMRI), we sought to preoperatively characterize prostate cancer (PCa) in the setting of antiandrogen plus androgen deprivation therapy (AA-ADT) prior to robotic-assisted radical prostatectomy (RARP). We present our preliminary findings regarding mpMRI depiction of changes of disease staging features and lesion appearance in treated prostate.Methods: Prior to RARP, men received 6 months of enzalutamide and goserelin. mpMRI consisting of T2 weighted, b = 2,000 diffusion weighted imaging, apparent diffusion coefficient mapping, and dynamic contrast enhancement sequences was acquired before and after neoadjuvant therapy. Custom MRI-based prostate molds were printed to directly compare mpMRI findings to H&E whole-mount pathology as part of a phase II clinical trial (NCT02430480).Results: Twenty men underwent imaging and RARP after a regimen of AA-ADT. Positive predictive values for post-AA-ADT mpMRI diagnosis of extraprostatic extension, seminal vesicle invasion, organ-confined disease, and biopsy-confirmed PCa lesions were 71%, 80%, 80%, and 85%, respectively. Post-treatment mpMRI correctly staged disease in 15/20 (75%) cases with 17/20 (85%) correctly identified as organ-confined or not. Of those incorrectly staged, 2 were falsely positive for higher stage features and 1 was falsely negative. Post-AA-ADT T2 weighted sequences best depicted presence of PCa lesions as compared to diffusion weighted imaging and dynamic contrast enhancement sequences.Conclusion: mpMRI proved reliable in detecting lesion changes after antiandrogen therapy corresponding to PCa pathology. Therefore, mpMRI of treated prostates may be helpful for assessing men for surgical planning and staging. [ABSTRACT FROM AUTHOR]

T-cell receptor alternate reading frame protein (TARP) is a 58-residue protein over-expressed in prostate and breast cancer. We investigated TARP peptide vaccination's impact on the rise in PSA (expressed as Slope Log(PSA) or PSA Doubling Time (PSADT)), validated tumor growth measures, and tumor growth rate in men with Stage D0 prostate cancer. HLA-A*0201 positive men were randomized to receive epitope-enhanced (29-37-9V) and wild-type (27-35) TARP peptides administered as a Montanide/GM-CSF peptide emulsion or as an autologous peptide-pulsed dendritic cell vaccine every 3 weeks for a total of five vaccinations with an optional 6th dose of vaccine at 36 weeks based on immune response or PSADT criteria with a booster dose of vaccine for all patients at 48 and 96 weeks. 41 patients enrolled with median on-study duration of 75 weeks at the time of this analysis. Seventy-two percent of patients reaching 24 weeks and 74% reaching 48 weeks had a decreased Slope Log(PSA) compared to their pre-vaccination baseline (p= 0.0012 andp= 0.0004 for comparison of overall changes in Slope Log(PSA), respectively). TARP vaccination also resulted in a 50% decrease in median tumor growth rate (g): pre-vaccineg= 0.0042/day, post-vaccineg= 0.0021/day (p= 0.003). 80% of subjects exhibited new vaccine-induced TARP-specific IFNγ ELISPOT responses but they did not correlate with decreases in Slope Log(PSA). Thus, vaccination with TARP peptides resulted in significant slowing in PSA velocity and reduction in tumor growth rate in a majority of patients with PSA biochemical recurrence. [ABSTRACT FROM PUBLISHER]