pROSTAE CANCER AND BLADDER CANCER

[CRACKERJIM]

Is there any definitive data that relates non-invasive Prostate cancer and Bladder cancer? I have both. I have seen several boards where there seems to be a significant number of patients who have both. Would also be interested in any studies that relate radiation therapy (i.e., brachytherapy) to potential cause of Bladder Cancer.

[riley180]

I can’t give you direct data from a patient series or registry but since the prostate is non-invasive (uncertain if the description applies to the bladder) the two cancers are likely independent events. From ACS 2007 data, of 1.4 million new cases, 767,000 are in men, of which 29% have prostate cancer and 7% have bladder. The odds of having both (from extrapolation) is 1/33 of these new cases, that comes to about 6000 men. These numbers however, involve all prostate cancers (including the invasive) so the actual figure we could expect to be smaller.
The incidence of secondary bladder cancer from radiation is roughly 1% for conventional RT (I don’t have data for brachytherapy). The incidence is expected to increase (to about 1.75%) with higher doses of radiation as those employed in IMRT. However, it must be remembered that the development of the secondary malignancy may take up to ten years, so life expectancy of patients plays a factor with a higher incidence for those who are younger when treatment was received.
Int J Radiat Oncol Biol Phys. 2003 May 1;56(1):83-8

[riley180]

I repeated my calculations, and the more accurate figure for the prostate and bladder cancer comes to 1/50, of the 767000 new cancers in men, about 15000 may have the aforementioned sites involved.