THE "NEW" PROSTATE CANCER INFOLINK

There are a number of additional reports in today’s news (above and beyond the reports on risks associated with disseminated tumor cells and a new review of PSA and PCA3 testing as aids to diagnosis):

It has been widely suggested that ideal candidates for focal therapy are likely those with unilateral prostate cancer (i.e., prostate cancer in just one of the two prostate cancer lobes). Tareen et al. set out to validate this hypothesis by reviewing the charts of 1,458 consecutive patients who underwent open radical prostatectomy, as performed by a single surgeon. Patients were divided into a unilateral group (n =  311) and a bilateral group (n = 1,147) based on their final surgical pathology. They were also stratified into low risk (PSA < 10 ng/ml, clinical stage < T2b or Gleason score < 7) and high risk groups. Compared to patients with bilateral disease, those with unilateral disease had a lower rate of extracapsular extension (p = 0.004), less seminal vesical invasion (p = 0.003),  less tumor involvement ≥ 10 percent (p < 0.001), and a higher incidence of Gleason scores ≥ 7  (p < 0.001). At a median follow-up of 36 months, 8.3 and 16.7 percent of the men in the unilateral and bilateral groups, respectively, experienced biochemical recurrence (p = 0.001). Low risk disease was more prevalent in those with unilateral disease than in those with bilateral disease. Of men with low risk disease the risk of adverse pathological features/biochemical recurrence did not differ between the two groups. The authors conclude that, “Although men with unilateral prostate cancer have more favorable oncological outcomes than those with bilateral prostate cancer, this appears to be due to the higher prevalence of low risk disease. While focality/laterality may direct the method of subtotal gland treatment, clinical risk features may be adequate to select candidates for focal therapy.”

A very small Phase II pilot trial by Schwenke et al. in men with hormone refractory prostate cancer has provided no evidence that lycopene (an active agent found naturally in tomatoes) has any “clinically relevant benefits … for patients with advanced stages of the disease.”

Using the CellSearch™ system, Okegawa et al. have investigated whether circulating tumor cells (CTCs) predict survival in 64 patients with hormone refractory prostate cancer. They conclude that 5 or more CTCs in 7.5 ml blood was associated with survival in patients with hormone refractory prostate cancer, and go on to state that CTCs “may be an independent predictor of overall survival in patients with hormone refractory prostate cancer but they may also complement prostate specific antigen.”

An agent known as silibinin has recently completed a Phase II clinical trial in prostate cancer patients; however, its antitumor effects and mechanisms are not well understood. Singh et al. have reported that silibinin appears to have multiple targeted effects on prostate cancer cells in a mouse model that “provide evidence for antitumor efficacy … and support its clinical investigation in prostate cancer.”

Filed under: Diagnosis, Drugs in development, Management, Risk, Treatment | Tagged: circulating tumor cells, CTC, focal therapy, lycopene, silibinin, unilateral |