“In the Spanish phase III DART01/05 GICOR trial reported in Lancet Oncology, Zapatero and colleagues found that long-term androgen-deprivation therapy (ADT) increased biochemical disease-free survival and overall survival vs short-term ADT when combined with high-dose radiotherapy in men with localized prostate cancer.
“In this open-label trial, 355 patients were randomly assigned between November 2005 and December 2010 to receive 4 months of ADT (n = 178) or 24 months of ADT (n = 177) following three-dimensional conformal radiotherapy at a minimum dose of 76 Gy (range, 76–82 Gy). Patients had to have clinical stage T1c–T3b, N0, M0 prostate adenocarcinoma with intermediate or high risk based on 2005 National Comprehensive Cancer Network criteria.
“The short-term ADT group received 4 months of neoadjuvant and concomitant androgen deprivation with subcutaenous goserelin (Zoladex) 2 months before and 2 months in combination with high-dose radiotherapy, with flutamide at 750 mg/d or bicalutamide at 50 mg/d added during the first 2 months of treatment. Patients in the long-term ADT group continued with the same luteinizing hormone–releasing hormone analog every 3 months for 24 months. The primary endpoint was biochemical disease-free survival on intention-to-treat analysis.”
“Low-dose brachytherapy boosts held prostate cancer in check significantly better than dose-escalated external-beam radiation therapy (EBRT) in men with unfavorable-risk disease, a randomized trial showed.
“Patients treated with brachytherapy after androgen deprivation therapy (ADT) and whole-pelvis EBRT had an estimated 9-year relapse-free survival (RFS) of 83% compared with 63% for patients who received a conformal EBRT boost. The difference in favor of brachytherapy emerged after 5 years of follow-up, Scott Tyldesley, MD, of the British Columbia Cancer Agency in Vancouver, reported here at the Genitourinary Cancers Symposium.
” ‘In the context of 12 months of androgen deprivation therapy and whole pelvis external beam radiotherapy, treatment with a low-dose pelvic brachytherapy boost results in a 50% reduction in biochemical relapse compared to dose-escalated EBRT to 78 Gray,’ Tyldesley said. ‘At 6.5 years of follow-up, there was no difference in overall survival, prostate cancer specific survival, or metastasis-free survival.’
“However, ‘there was increased late grade 3 or higher GU toxicity with the low-dose rate boost, a 5% to 6% increase in the prevalence of late GU toxicity,’ he said.”
“A ‘home run’ in advanced prostate cancer did not clear the fence in a second evaluation of androgen deprivation therapy (ADT) with docetaxel, according to a study reported here.
“An updated analysis of a French study showed that adding chemotherapy to ADT did not significantly improve overall survival for men with hormone-sensitive, metastatic prostate cancer. However, the 13-month difference in favor of the docetaxel arm was comparable to the statistically significant 14-month improvement observed in a larger U.S. trial reported last year.
“The French study also failed to show a survival benefit in patients with high-volume disease, which accounted for two-thirds of the patients in the U.S. trial.
” ‘We are awaiting the analysis of [a third randomized trial], and we hope to come up with a common analysis of the three studies altogether in order to give the good [best] treatment for the good [best] patient,’ Gwenaelle Gravis, MD, of Institut Paoli-Calmettes in Marseilles, France, said here at the Genitourinary Cancers Symposium.
“For more than 40 years, ADT has represented standard of care for metastatic hormone-sensitive advanced prostate cancer. The emergence of effective chemotherapy for castration-resistant prostate cancer led to speculation that use of cytotoxic therapy in hormone-sensitive advanced prostate cancer might improve outcomes as compared with ADT alone.”
“Preliminary results from the phase II STAND trial have demonstrated a robust immune response with sipuleucel-T (Provenge) that continues 2 years after completing treatment in men with biochemically recurrent prostate cancer. The findings, along with data from an ongoing phase IV registry related to increasing enrollment of African Americans in prostate cancer trials, are being presented at the 2015 Genitourinary Cancers Symposium, held February 26 to 28 in Orlando…
“The STAND study (Abstract 171) is a randomized, phase II trial that consisted of two patient study groups. One group completed sipuleucel-T 2 weeks before initiation of androgen-deprivation therapy, and the second received the drug 3 months after the start of androgen-deprivation therapy. Preliminary results from STAND indicate that immune responses were observed in both study arms and suggest there may be a greater cellular immune response in patients who received sipuleucel-T prior to androgen-deprivation therapy. Humoral immune responses were observed and similar between both treatment arms.
“ ‘It is very encouraging to observe that [sipuleucel-T] provides an immune response in men with biochemical-recurrent prostate cancer long after the course of androgen deprivation therapy has ended,’ said Neal Shore, MD, Medical Director at the Carolina Urologic Research Center. ‘This study may also provide guidance on the optimal sequencing of immunotherapy and androgen-deprivation therapy in biochemical-recurrent prostate cancer.’ ”
“An 8-year analysis confirmed that adding radiotherapy to androgen deprivation therapy (ADT) in men with locally advanced prostate cancer improved overall survival and reduced the risk of prostate cancer–specific death. The median overall survival was 10.9 years in the combination arm compared with 9.7 years in the ADT-alone arm.
“This final analysis is published in the Journal of Clinical Oncology.
“The original results of this international NCIC Clinical Trials Group PR.3 trial were published in the Lancet in 2011. This prior interim analysis showed a significant improvement in overall survival for those in the ADT plus radiotherapy treatment arm (hazard ratio [HR] = 0.77; P = .033). Based on the results, radiotherapy was recommended as part of the standard therapy for prostate cancer.
“The NCIC trial is the largest study investigating the addition of radiotherapy to ADT.”
Androgen deprivation therapy (ADT) has long been a mainstay in the management of prostate cancer. Indeed, the vast majority of prostate cancers depend on androgens (hormones like testosterone) for their growth. Lowering testosterone levels with ADT is a reasonable approach. But it comes with two sets of problems. Continue reading…
The gist: Recent research found that prostate cancer patients have similar survival rates whether they have androgen deprivation therapy (ADT) before or after tumor-removal surgery. The study focused on men with intermediate- or high-risk prostate cancer who were treated between 1995 and 2002.
“Patients with intermediate- or high-risk prostate cancer demonstrated similar biochemical relapse-free survival, distant metastasis-free survival and OS regardless of whether they received androgen deprivation in the neoadjuvant or adjuvant settings, according to study results.
“Patients with localized prostate cancer typically undergo androgen deprivation therapy (ADT) in the neoadjuvant setting, concurrent with radiation therapy.
“Michael A. Weller, MD,of Cleveland Clinic, and colleagues assessed whether patients who underwent ADT in the adjuvant setting experienced different outcomes.
“The analysis included 515 patients treated with radiation therapy and ADT from 1995 to 2002. Of these patients, 311 underwent ADT in the neoadjuvant setting, beginning 2 to 3 months before the start of radiation therapy. The other 204 patients underwent ADT in the adjuvant setting, immediately after the completion of radiation therapy.”
The gist: The drug sipuleucel-T (Provenge) may be no better than watchful waiting and standard androgen deprivation therapy for certain prostate cancer patients. That was the conclusion of the German Institute for Quality and Efficiency in Health Care (IQWiG). The IQWiG analyzed data on men with metastatic prostate cancer who had few or no symptoms and did not yet need chemotherapy.
“Sipuleucel-T (trade name Provenge) has been approved since September 2014 for men with metastatic prostate cancer who have few or no symptoms and do not yet require chemotherapy. The German Institute for Quality and Efficiency in Health Care (IQWiG) examined in a dossier assessment whether the drug offers patients an added benefit over one of the appropriate comparator therapies.
“According to the findings, an added benefit is not proven: The data on mortality were not evaluable because differences between the treatment groups might have been caused by the circumstances of the subsequent therapies. At the same time, certain side effects such as fever occur more frequently.
“Treatment with sipuleucel-T aims to stimulate the immune system to kill cancer cells. Immune cells are extracted from the patient’s blood and treated with a protein in a laboratory. These treated cells are then injected back into the patient’s blood where they are supposed to better recognize cancer cells and stimulate the immune system to fight the prostate cancer.
“Sipuleucel-T is an option for patients whose cancer has already formed metastases and can also no longer be influenced by blocking the hormone testosterone (hormone refractory).”
“A common prostate cancer therapy should not be used in men whose cancer has not spread beyond the prostate, according to a new study led by researchers at Henry Ford Hospital.
“The findings are particularly important for men with longer life expectancies because the therapy exposes them to more adverse side effects, and it is associated with increased risk of death and deprives men of the opportunity for a cure by other methods.
“The research study has been published online in European Urology.
“The focus of the new study is androgen deprivation therapy (ADT), in which an injectable or implanted medication is used to disrupt the body’s ability to make testosterone. ADT is known to have significant side effects such as heart disease, diabetes, increased weight gain and impotence; however a growing body of evidence suggests ADT may in fact lead to earlier death.
“Since the 1940s, the therapy has been a mainstay of treatment for prostate cancer that has metastasized, or spread beyond the prostate gland. Still other studies support the use of ADT when it is used as an adjuvant, or in addition to, radiation therapy for higher risk prostate cancer. No evidence exists to support the exclusive use of ADT for low risk or localized prostate cancer.”