ASCO 2015: Notable Reports on Prostate Cancer Treatment


This year’s American Society of Clinical Oncology (ASCO) annual meeting was short on any truly exciting developments in prostate cancer treatment. In stark contrast to other cancers, such as lung, breast, kidney, and melanoma, there were no reports of note on targeted and immunotherapies in prostate cancer. The two presentations summarized here offered new strategies in chemotherapy. Continue reading…


Addition of Chemotherapy Drugs to Androgen Suppression Improves Relapse-Free Survival in High-Risk Localized Prostate Cancer

“In a French phase III trial (GETUG 12) reported in The Lancet Oncology, Fizazi et al found that the addition of docetaxel and estramustine (Emcyt) to androgen-deprivation therapy (ADT) improved relapse-free survival among patients with high-risk localized prostate cancer…

“In the open-label trial, 413 patients with treatment-naive disease and at least one risk factor (stage T3-T4, Gleason score ≥ 8, prostate-specific antigen [PSA] concentration > 20 ng/mL, or pathologic node-positive disease) underwent staging pelvic lymph node dissection and were randomized to ADT (goserelin 10.8 mg every 3 months for 3 years) plus four cycles of docetaxel 70 mg/m2 on day 2 and estramustine 10 mg/kg/d on days 1 to 5 every 3 weeks (n = 207) or ADT alone (n = 206). Local treatment was administered at 3 months. The primary endpoint was relapse-free survival in the intention-to-treat population. Follow-up for other endpoints is ongoing.

“The chemotherapy and ADT alone groups were balanced for age (median 62 and 62 years), Gleason score (42% and 43% ≥ 8), pathologic node-positive status (29% in both), and serum PSA level (> 20 ng/mL in 59% in both).”


Adding ADT to RT Improved PFS After Radical Prostatectomy

“Assigning men in biological relapse after radical prostatectomy to combined salvage treatment with hormone therapy and radiation therapy significantly delayed disease progression compared with radiation therapy alone, according to the results of the GETUG-AFU 16 phase III trial (abstract 5006).

“ ‘Salvage radiotherapy combined with limited androgen deprivation therapy improves the 5-year progression-free survival rate compared to radiotherapy alone,’ said study presenter Christian Carrie, MD, of the department of radiation oncology at the University of Lyon-Centre Leon Berard. ‘There is no significant difference in overall survival, but the follow-up is still too short.’

“Between October 2006 and March 2010, 743 patients were enrolled in GETUG-AFU 16 and randomly assigned to radiation therapy alone (n = 374) or radiation plus hormone therapy with goserelin 10.8 mg for 6 months (n = 369). The primary endpoint of the trial was progression-free survival.”


Metabolic Syndrome up with ADT in Prostate Cancer

“For patients with prostate cancer treated with androgen deprivation therapy there are increases in components of metabolic syndrome and in the prevalence of full metabolic syndrome, according to a study published in the June issue of The Journal of Urology.

“Juan Morote, M.D., from Hospital Vall d’Hebron and Universitat Autónoma de Barcelona in Spain, and colleagues conducted an observational prospective study involving 539 prostate cancer patients scheduled to receive three-month depot luteinizing hormone-releasing hormone analogs for longer than 12 months. The authors examined the prevalence of full metabolic syndrome, assessed according to different definitions, and its components…

” ‘Counseling patients on the prevention, early detection, and treatment of specific metabolic alterations is recommended,’ the authors write.”


ASCO: Chemo-ADT Combo Still Winning in Prostate Cancer

“Men with advanced prostate cancer lived significantly longer if they received upfront chemotherapy in addition to androgen deprivation, results of a randomized trial showed.

“As compared with men who received only androgen deprivation therapy (ADT), those who also got docetaxel had a 10-month improvement in median overall survival (OS). The difference translated into a 24% reduction in the mortality hazard. Subgroup analysis showed that patients with metastatic disease at the start of treatment derived even greater benefit from docetaxel, a 22-month improvement in median overall survival.

“The study is at least the third reported within the past year showing a significant survival benefit with upfront docetaxel, making a strong case for standard of care, as reported during a press briefing prior to the American Society of Clinical Oncology meeting, which begins here May 29.

” ‘Our headline conclusion would be that docetaxel would be considered routine therapy for men with newly diagnosed metastatic disease,’ said Nicholas James, MD, of the University of Warwick and Queen Elizabeth Hospital in Birmingham, England.”


Men Receiving Androgen Deprivation Therapy may Experience Cognitive Impairment

“Cognitive impairment can occur in cancer patients who are treated with a variety of therapies, including radiation therapy, hormone therapy, and chemotherapy. After chemotherapy treatment it is commonly called ‘chemo brain.’ Signs of cognitive impairment include forgetfulness, inability to concentrate, problems recalling information, trouble multi-tasking and becoming slower at processing information. The number of people who experience cognitive problems following cancer therapy is broad, with an estimate range of 15 to 70 percent.

“There have been several studies analyzing this side effect in breast cancer patients, but few have investigated cognitive impairment following androgen deprivation therapy (ADT) for men being treated prostate cancer. A new Moffitt Cancer Center study indicated that men who are on androgen deprivation therapy have greater odds of experiencing impaired cognitive function.

“Androgen deprivation therapy is commonly used to treat prostate cancer, often on an open-ended basis for therapy of advanced prostate cancer. It is estimated that 44 percent of men with prostate cancer undergo ADT at some point. The goal of this type of therapy is to block the male hormones, including testosterone, from stimulating the growth of the prostate cancer cells. However, the side effect of ADT on cognitive function in men with prostate cancer has not been measured as much.”


Statin Drugs Can Delay Prostate Cancer Progression in Patients Receiving Androgen Deprivation Therapy, Study Shows

“Men who went on cholesterol-lowering statin drugs when they began androgen deprivation therapy for prostate cancer had a longer time in which their disease was under control than did men who didn’t take statins, a clinical trial led by Dana-Farber Cancer Institute investigators shows.

“In a study published online today by JAMA Oncology, the researchers report that men who had been taking statins since the start of androgen deprivation therapy (ADT) went a median of 27.5 months before their disease began to worsen, compared to 17.4 months for men who didn’t take statins. The trial involved 926 patients, 70 percent of whom had their disease progress during a six-year period.

“ ‘This median 10-month benefit in delaying disease progression suggests that statins could be a valuable addition to our current therapies for prostate cancer,’ says the study’s first author, Lauren Harshman, MD, medical oncologist at the Lank Center for Genitourinary Oncology at Dana-Farber. ‘These results are supported by multiple prior epidemiologic studies demonstrating that statin use may be associated with improved outcomes in prostate cancer, but require validation.’ “


Cixutumumab Shows No Effect in Metastatic Castration-Resistant Prostate Cancer

“In a randomized phase II trial (SWOG S0925) reported in the Journal of Clinical Oncology, Yu et al found that the addition of cixutumumab to androgen-deprivation therapy did not significantly increase the rate of undetectable prostate-specific antigen (PSA) in patients with newly diagnosed metastatic hormone-sensitive prostate cancer. Cixutumumab inhibits the insulin-like growth factor I receptor (IGF-IR).

“In the study, 210 patients from SWOG institutions were randomly assigned between February 2011 and December 2012 within 30 days of starting androgen deprivation to receive bicalutamide daily with a luteinizing hormone-releasing hormone agonist alone (n = 105) or with cixutumumab at 10 mg/kg given intravenously over 1 hour every 2 weeks for seven 28-day cycles. The primary endpoint was rate of undetectable PSA (≤ 0.2 ng/mL) at 28 weeks.

“The cixutumumab and control groups were generally balanced for baseline characteristics, including age (median, 65 and 66 years), PSA level (median, 31 and 37 ng/mL), Gleason score (≥7 in 60% and 78%), race (89% and 84% white), metastasis site (lymph node only in 14% and 9%, bone only in 53% and 60%, both in 18% and 16%, visceral in 14% and 15%), and early-induction androgen deprivation (56% and 62%).”


Radioactive Implants Improve Survival in High-Risk Prostate Cancer

“Results from a randomised controlled trial to compare the use of permanent radioactive implants (brachytherapy) with dose-escalated external beam radiotherapy in patients with prostate cancer show that the men who received brachytherapy were twice as likely to be cancer-free five years later.

“Presenting these results at the 3rd ESTRO Forum in Barcelona, Spain, today (Monday) Professor James Morris, from the Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency (BCCA), Vancouver, Canada, will say that the ASCENDE-RT trial is the first and only existing trial comparing low-dose-rate prostate brachytherapy (LDR-PB) for the curative treatment of prostate cancer with any other method of radiation therapy delivery.

“The trial enrolled 398 men with cancer that had not spread outside the prostate gland who were judged to be at high risk of treatment failure, based on standard tests for a number of features of the cancer. The patients initially received androgen deprivation therapy (ADT), aimed at reducing levels of the male hormones that stimulate prostate cancer cells to grow. After eight months of ADT, all patients received 46 Gy of external beam radiotherapy to the prostate and regional lymph nodes.”