THE "NEW" PROSTATE CANCER INFOLINK

Recent reports have addressed the following issues related to prostate cancer:

• How many biopsy cores is the right number?
• How “open” surgeons have adapted to laparoscopic surgery
• Hypoxia, the tumor environment, and how it affects treatment
• Gefitinib + radiation therapy in intermediate- and high-risk prostate cancer
• Fractures, prostate cancer, and androgen deprivation

Jiang et al. have proposed that the volume to biopsy core ratio (VBR) — i.e., the volume of the prostate divided by the number of biopsy cores taken — can be used to define the appropriate number of biopsy cores to be taken from a specific patient in order to optimize the probability of identifying prostate cancer in that patient while minimizing the need for unnecessary biopsy samples. They state that a VBR of 4 offers a 50 percent probability of prostate cancer detection (compared to a 42 percent detection rate with a VBR of 2 and a 59 percent detection rate with a VBR of 5) and “maintains high cancer detection rates without taking an excessive number of biopsy specimens.” What does this mean for a patient? It implies that a man with an estimated prostate volume of 60 cm³ should have 15 cores taken on biopsy.

Acharya et al. have reported on the ways in which specialized urologic surgeons who were initially trained to carry out “open” retropubic or perineal radical prostatectomies have adapted to the increasing use of minimally invasive forms of these operations.

Stewart et al. have reviewed available data on the roles of hypoxia and the tumor microenvironment in the treatment of prostate cancer. To put this into simple English, they have reviewed available information on whether low oxygen levels in the tissues immediately surrounding prostate cancer cells can impact the effects of specific prostate cancer treatments (such as radiation therapy). They note that while this field is intellectually interesting, it is currently extremely difficult to actually measure oxygen levels in prostate tissue in a patient undergoing treatment, so applying current knowledge into the clinic is all but impossible at present.

A Finnish research team has reported that it is possible to give chemotherapy with gefitinib (Iressa) in combination with external beam radiation for first-line treatment of patients with clinical stage T2b-T3NoM0 disease and a PSA of < 20 ng/ml. Patients have been followed for a median of 38 months, with no prostate cancer-specific deaths. However, there was a notable toxicity level in 38 percent of the patients in this trial, and it is probably too small to be able to make any decisions about effectiveness as a first-line treatment for intermediate and high-risk patients.

An article by Lau et al., based on a review of data from nearly 20,000 Canadian men, has reported that there is no association between a diagnosis of prostate cancer and an increased risk for fractures of the hip, the vertebrae, or the wrist. However, they confirm that there is a clear association between treatment with androgen deprivation (ADT) and an increased risk for fractures of the same bones.

Filed under: Diagnosis, Management, Risk, Treatment, Uncategorized | Tagged: ADT, androgen deprivation therapy, biopsy, fractures, gefitinib, hypoxia, Iressa, microenvironment, radical prostatectomy, tumor |