It is generally agreed that prostate cancer which is still 100% confined to the prostate gland is curable using local therapies like radiation or surgery, but when it has left the prostate gland and becomes metastatic it is no longer curable. Treatment for metastatic prostate cancer is intended to make the prostate cancer a chronic illness, allowing the man to live with the disease long enough to benefit from new and better treatments and long enough to die from another, unrelated cause. I often say that my prostate cancer treatment is designed to allow me to be killed by getting hit by a bus (actually, I can think of many more desirable ways to meet my end).
But evidence now says there might be an intermediate stage of prostate cancer where the cancer has spread outside the prostate gland but is still in small numbers and is confined to a limited area immediately surrounding the prostate gland. This intermediate stage is called oligometastatic prostate cancer.
Oligometastatic disease was first described in a paper written in 1995 by Samuel Hellman and Ralph Weichsel¬baum (Hellman, S & Weichselbaum, RR J. Clin. Oncol 12:8, 1995). This paper was not written specifically about prostate cancer, but its relevance to prostate cancer is undeniable.
The paper as well as a follow up paper they wrote stated that some patients with oligometastatic cancer can have their survival markedly prolonged when the metastatic lesions are targeted surgically or treated with radiation despite there having left the original organ site. Hellman and Weichselbaum evaluated patients with liver metastases removed by surgery who have survived long enough that they are very likely cured and among patients with lung metastases removed by surgery (between 20-30% were still alive at 15 years), not prostate cancer.
Many people in the prostate cancer community are very aware of Dr. Snuffy Myers was diagnosed with oligometastatic prostate cancer in the lymph nodes. At the time of his diagnosis statistics showed that at best he could have expected only 10 years of survival before he would succumb to the prostate cancer.
Dr. Meyers, with the help of Dr. Michael Dattoli was treated with radiation to the prostate gland and lymph nodes in the pelvis. Additionally, surgery was used to eliminate the lymph nodes in the lower abdomen that might have been involved. All of this was done after hormonal therapy had been used to reduce the total volume of cancer. As of this date, Dr. Meyers has long survived his 10 year date with death.
One person exceeding the 10 year date is not scientific proof, but Dr. Meyers and Dr.Dattoli continue to use this treatment with great success.
When Dr. Meyers was treated it was very difficult to visualize these metastatic lesions, but since then our scanning abilities have greatly improved. Not only are the scanners become more sensitive, but we now have new contrast agents that enhance the ability to visualize these lesions. We should be seeing many more Dr. Meyers type of survival stories.
In 2004 at the University of Rochester in New York, the existence of oligometastatic disease in prostate cancer was documented (Singh, D, et al O Int J Rad Onc Biol Phys 58: 3, 2004). The first observation was that men with five or fewer bone lesions had nearly the same 5-year survival as those with PSA-only recurrences.
They found that in men with five or fewer bone lesions (versus more than 5) remained stable for up to several years before the cancer started to spread widely. Those with more than five bone lesions were much more likely to spread widely.
It was proposed that stereotactic radiation to bone metastases in those with five or fewer may eliminate the bone metastatic cancer and make the patients disease-free for a prolonged period of time. After the publication of this paper there were several other papers that hinted that radiation can indeed control individual bone lesions. However, because of small patient numbers and limited follow-up, these papers can not be considered as proof.
Currently, there is one clinical trial looking at oligometastatic prostate cancer. It is entitled: Non-systemic Treatment for Patients With Low-volume Metastatic Prostate Cancer. On the web page www.clinicaltrials.com its Identifier is NCT01558427.
I have heard of another study being conducted by Dr. Patrick Cheung at Sunnybrook Health Sciences Center in Toronto, Canada (www.sunnybrook.ca) where this therapy is being evaluated. However, I have not been able to locate the actual information about this study.
This explains the story as to why it is so important to be vigilant in following your PSA post primary treatment. Catching the spread of prostate cancer while is is limited and in a nearby location to the prostate gland is vital to permit you a second swing at putting the cancer into a remission that will outlive you.
Joel T. Nowak, M.A., M.S.W.