THE "NEW" PROSTATE CANCER INFOLINK

Today’s news includes information on:

• The use of markers for prognosis following first-line treatment for localized prostate cancer
• Results of a Phase II trial of neoadjuvant docetaxel + gefitinib prior to radical prostatectomy
• Results of a Phase III trial of gabapentin in management of ADT-related “hot flashes”
• MRI-directed HIFU in the treatment of localized prostate cancer

Sutcliffe et al. have conducted a systematic, evidence-based review of the prognostic value of novel and classical markers in the management of localized prostate cancer in an attempt to identify the best available prognostic model currently available. The bottom line? PSA velocity or PSA doubling time currently appear to be the best available markers for monitoring patients over time and using that data to assess prognostic risk. The authors made the important point that, “This review highlighted the poor quality and heterogeneity of studies, which render much of the results inconclusive. It also pinpointed the small proportion of models reported in the literature that are based on patient cohorts with a mean or median follow-up of at least 5 years, thus making long-term predictions unreliable.”

Vuky et al. have published the initial results of a Phase II trial designed to assess the efficacy and toxicity of docetaxel (Taxotere) and gefitinib (Iressa) in 31 patients with high-risk localized prostate cancer as neoadjuvant therapy for 2 months prior to radical prostatectomy (RP). All patients met the criteria of clinical stage T2b-3 or a serum PSA level >20 ng/ml, or a Gleason score of 8 to 10. The primary endpoint was complete pathologic response. Thirty patients (96.8 percent) received all scheduled therapies including RP. No patients demonstrated a complete pathologic response to this treatment regimen. Twenty-nine patients (94 percent) achieved a partial clinical  response, including 11 patients (35 percent) who demonstrated radiographic improvement on endorectal MRI. Grade 3 toxicities included asymptomatic liver function test elevation in 4 (13%) patients, diarrhea in 1 (3%) patient, and fatigue in 1 (3%) patient.  One patient experienced grade 4 toxicity with elevated alanine aminotransferase. Post-surgical specimen pathology demonstrated residual carcinoma in all cases.

Loprinzi et al. have published the results of a randomized, prospective, double-blind, placebo-controlled clinical trial of gabapentin (at target doses of 300, 600, or 900 mg/day) vs. placebo in 214 eligible prostate cancer patients with hot flashes on a stable androgen deprivation therapy program. Hot flash frequencies and severities were recorded daily during a baseline week and for 4 weeks while the patients took the study medication. Comparing the fourth treatment week to the baseline week, mean hot flash scores decreased in the placebo group by 4.1 units and in the three increasing dose gabapentin groups by, 3.2, 4.6, and 7.0 units respectively. The gabapentin was well tolerated in this trial. The results support the idea that (at least at a dose of 900 mg/day) gabapentin decreases hot flashes, to a moderate degree, in men with androgen ablation-related vasomotor dysfunction.

Finally, additional information is starting to become available about a new form of prostate cancer therapy (theoretically usable for complete prostate ablation or for focal therapy) that is based on a combination of high-intensity focused ultrasound (HIFU) and real-time MRI-based guidance. The basic technology has been developed by Profound Medical, Inc. The technology to synchronize the technology with MRI guidance has been provided by Johnson MedTech. For more information we suggest you visit the Profound Medical web site. Will also provide a link to today’s media release from Johnson MedTech as soon as this is available on their web site. The “New” Prostate Cancer InfoLink notes that as yet this technology has not been approved for use in the USA.

Filed under: Drugs in development, Living with Prostate Cancer, Management, Treatment | Tagged: docetaxel, doubling time, gabapentin, gefitinib, HIFU, hot flashes, PSA velocity |