PARP Inhibition in Recurrent Prostate Cancer - Episode 1
Nicholas J. Vogelzang, M.D., FASCO, FACP: Prostate cancer occurs in between about 200,000 and 250,000 men a year. Prostate cancer comes in five general varieties. We have summarized those, initially in what was called the Gleason score, that was one to 10. That has been contracted down to one to five. They come in five types; one, two, three, four, and five.
There are other types, rare subtypes, and those are dealt with on a separate basis, including sarcomas and small cell carcinomas, but typically we’re dealing with the 5 types. Once a patient is diagnosed, the first thing we want to know is what type you have. The diagnosis is made based upon the PSA blood test, prostate-specific antigen. It’s a blood test that has been used for many years. It is effective for measuring the amount of prostate cancer in the blood. If the PSA is a little bit elevated, that leads to a suspicion that you may be dealing with prostate cancer.
The next step is the rectal exam. That is then followed by either an MRI [magnetic resonance imaging] of the prostate or a prostate biopsy. Based upon the biopsy, the diagnosis is made. The results can range from a little bit of cancer to a large amount of cancer. And it also is a function of your PSA number. PSA can be normal, it can be high, or it can be very high. Everyone is categorized by their PSA number, by their grade group, one through five. And usually, depending upon what the number is, we do what we call staging. This includes the bone scan, CT scan, [computed tomography] and in many patients, an MRI 3T, that’s tesla, 3T, or three tesla MRI, which is specific for the prostate tissue, in prostate cancer diagnoses. At the end of that period we categorize the patient as to what stage they are.
All patients will be categorized into where the cancer is. There are three basic categories of where the cancer is: localized; regional, that is outside of the prostate maybe in lymph nodes; or metastatic, that is spread to the bones or other organs. There is debate as to whether a lymph node should be considered metastatic. Generally, we call that metastatic, but it’s a different category. My patient today had a PSA of 84 [ng/mL], his grade group was four, and he had it in lymph nodes. He was treated with hormone treatment alone, and then today I recommended that he also have radiation to the prostate, to the lymph nodes, and hopefully will be cured. Each patient falls into those categories, and you must be careful to get it right, because a lot of the patients are curable.
And a lot of the patients, particularly those in grade group one, that have only little bits of cancer in the prostate, don’t need any treatment at all. The treatments vary by the type of cancer they have. If you’re a grade group one, relatively low PSA, good MRI findings, you may not need to be treated. On the other hand, if you’re a grade group three or four within the prostate, you should be treated with radiation or a surgery. If you’re a four and have it outside of the prostate, you’ll need to have the hormone treatment and maybe radiation or surgery.
For those that are spread outside of the prostate in the bones or other, hormone treatment, ablation of the male hormone, testosterone, antitestosterone therapy is indicated. That’s a very broad overview of the field.
Transcript Edited for Clarity