Prostate Cancer

SOUTH SAN FRANCISCO-Cell Genesys terminated VITAL-2, the second of two phase III clinical trials of Gvax immunotherapy for prostate cancer.

In the article entitled "Interstitial Brachytherapy Should Be Standard of Care for Treatment of High-Risk Prostate Cancer," Merrick, Wallner, and Butler once again make the case for interstitial brachytherapy as a primary treatment for prostate cancer (see their earlier article, "Permanent Prostate Brachytherapy: Is Supplemental External-Beam Radiation Therapy Necessary?" in ONCOLOGY, April 2006).[1] This time Nathan Bittner has joined as the lead author.

In this issue of ONCOLOGY, Bittner et al provide a thoughtful review of the literature to advocate for the viewpoint that interstitial brachytherapy should be standard of care for the treatment of high-risk prostate cancer.

In the realm of general oncology, patients who present with aggressive, poorly differentiated malignancies are usually at high risk for disseminated disease, and systemic therapy often supersedes local therapy in importance. It is not surprising, then, that a similar systemic approach to therapy is often considered for patients who present with high-risk prostate cancer. This recommendation is often supported by much of the surgical literature that cites discouraging outcomes in these patients when treated by radical prostatectomy alone.

The magnitude of the role surgical exploration and extirpation play in the contemporary management of patients with advanced ovarian cancer is hard to overstate. Beyond diagnostic confirmation, the aggressive posture taken to remove bulk disease provides-among other benefits-symptomatic relief, theoretically enhanced immunologic integrity, chemosensitivity, and improved survival characteristics.

Given the poor outcomes observed with radical prostatectomy (RP) and external-beam radiation therapy (EBRT), some in the urologic community contend that high-risk disease is not curable with currently available treatment strategies.[1,2] In fact, there is a growing contingent of clinicians who advocate the use of chemotherapy in conjunction with RP. With the established efficacy of brachytherapy, these efforts are likely excessive.

The standard management for advanced-stage ovarian cancer was established in the mid-1970s. At a 1974 National Cancer Institute Consensus Conference on Ovarian Cancer, Griffiths presented data supporting the role for aggressive cytoreductive surgery as the first step in the management of this disease, followed by cytotoxic chemotherapy.

A combination of two antiangiogenic agents-bevacizumab (Avastin) and thalidomide (Thalomid)-with docetaxel (Taxotere) is associated with a median progression-free survival of about a year and a half among men with metastatic, hormone-refractory prostate cancer, finds a phase II trial presented at ASCO 2008 (abstract 5000).

Treatment inside a 2-year window and a PSA doubling time of less than 6 months may be the key factors for optimizing salvage radiotherapy results for recurrent prostate cancer, according to investigators from the Brady Urological Institute at Johns Hopkins School of Medicine in Baltimore.

Mice that are prone to develop prostate tumors because they lack the PTEN tumor-suppressor protein remained cancer free when researchers disabled the growth-stimulating p110-beta protein, suggesting that this protein could be a promising prostate cancer drug target (Nature doi:10.1038/nature07091).

This is an expertly written summary of the experience with cryotherapy as primary treatment of prostate cancer and the rationale for proceeding toward more limited, organ-sparing approaches with this procedure as focal treatment for low-risk cancers. Growing evidence of overdetection and overtreatment in many men with low-risk tumors has resulted in the recognition that alternatives to conventional treatment strategies are needed. Observation, a laudable and appropriate approach, appeals to relatively few patients.

The article by Polascik and coauthors provides a timely synopsis of modern technologic advances in prostate cryoablation and a review of the rationale for and experience with targeted prostate treatments. Prostate cryoablation has a storied past, which can be briefly summarized as high excitement followed by near-complete abandonment. Fortunately, a few practitioners improved the technique and incorporated new technologies allowing for its resurrection.

Recently, third-generation cryosurgery has been widely introduced into clinical practice using argon-driven, ultrathin 17-gauge cryoprobes in accordance with the Joule-Thompson principle.[1-3] Contemporary cryosurgery includes these technologic advances along with the routine utilization of ultrathin needles incorporating a thermal monitoring system (TMS) for temperature surveillance, transrectal ultrasound (TRUS) imaging, and a urethral warming catheter to minimize morbidity associated with the procedure.[4-7]

CHICAGO-The combination of custir-sen sodium (OGX-011, OncoGenex Technologies Inc), an investigational agent, with docetaxel (Taxotere) or mitoxantrone has acceptable toxicity in patients with hormone-refractory prostate cancer who have experienced a failure of first-line docetaxel-based chemotherapy, investigators reported at ASCO 2008 (abstract 5002). Efficacy outcomes were somewhat better with the custirsen/docetaxel combination.

High-intensity focused ultrasonic (HIFU) ablation is used to manage localized prostate cancer after external beam radiation therapy. But post-treatment alterations to prostate zonal anatomy hamper the assessment of local tumor progression in order to make decisions about second-line treatment. An interdisciplinary group from South Korea tested two MRI techniques for predicting local tumor progression.

External-beam radiation is a highly effective curative treatment option for men with localized prostate cancer.[1,2] Over the past several decades, efforts have been made to improve the “therapeutic ratio” of radiation by increasing dose to improve cure rates without causing a substantial increase in side effects. Due to its potential to create superior dose distributions, proton therapy is considered by many to be the best available form of external radiation therapy. Here we will critically examine the evidence supporting the use of protons in the treatment of prostate cancer.

Financial pressures from Medicare reimbursement changes may have caused physicians to switch from providing hormonal-induced castration to providing surgical castration for men with prostate cancer. That is the finding of a new study published in the May 15 issue of CANCER. The study suggests that factors other than evidence-based medicine may have a significant influence on treatment decisions.

A drug proven effective in a large randomized prostate cancer prevention trial is rarely used for that indication. ONI explores the economic and clinical reasons underlying the agent's lack of use.

Medical castration has lost some ground as the preferred androgen deprivation treatment for prostate cancer, while use of surgical castration has increased slightly, according to researchers from the Cleveland Clinic.

Justifying the huge capital investment in proton beam therapy centers requires a strategic model, in other words, a high-volume disease, such as prostate cancer.

The patient is a 74-year-old male in generally good health. He reported having several episodes of prostatitis over the past 5–10 years. His prostate-specific antigen (PSA) levels rose to 5 ng/mL from an initial value of 2.6 ng/mL. Biopsies at this time were positive for malignancy in both lobes, clinical stage T2. His Gleason score was 6, suggesting that he had a favorable prognosis with a low risk of recurrence.

Most older men with early-stage prostate cancer will not require treatment or will die of other causes before their cancer progresses significantly, according to a retrospective study of 9,018 men from the SEER database. The men had been diagnosed with stage I-II disease between 1992 and 2002 and did not receive local therapy initially or hormonal therapy within 6 months of diagnosis.

Toremifene citrate (Acapodene) 80 mg reduced the occurrence of vertebral fractures and met other key endpoints in a phase III trial of 1,389 men receiving androgen deprivation therapy for advanced prostate cancer, GTx, Inc. said in a press release. Based on these findings, the company plans to file a New Drug Application with FDA by the summer of this year for the treatment of multiple side effects of ADT.

Compared with conventional intensity-modulated radiation therapy for prostate cancer, hypofractionated IMRT is not associated with any increase in sexual adverse effects, finds a randomized trial.

Researchers have reported finding a blood biomarker that enables close to 98% accuracy in predicting the spread of prostate cancer to regional lymph nodes. Their study is published in the March 1 issue of Clinical Cancer Research, a journal of the American Association for Cancer Research. The new blood test measures levels of endoglin, a plasma biomarker that has been previously shown to predict the spread of colon and breast cancer.