Little is known about the risk of multiple events, while the time to first event is well documented.
PCBaSe Sweden is based on the National Prostate Cancer Register, which covers >96% of CaP cases in Sweden. The number of fracture, stroke, CVD, and TED events that occurred after CaP diagnosis stratified by treatment group (ADT, curative treatment, or surveillance) and history of previous event(s) was assessed.
The analysis included 76,000 men diagnosed between 1997 and 2007, of whom 30,642 men received primary ADT, 26,432 curative treatment, and 19,526 surveillance. Mean follow up time was 4.1 years. 75% of all men did not have any event during follow-up, 17% had one event and 9% had more than one event. The incidence of any event was 10/100 person-years. The proportion of men with an event was largest among men on ADT treated patients and men on surveillance. Patients having an adverse event prior to diagnosis correlated with greater likelihood to develop another event after diagnosis. Of men who had a fracture (n=3,959) after CaP diagnosis, 64% had one fracture, 8% had several fractures, and 28% had one fracture combined with other events. Among men who had a stroke (n=4,879) 63% had one stroke, 9% developed several strokes, and 28% had one stroke combined with other events. Of men who had a CVD (n=10,589) 58% had one CVD (58%), 29% had several CVDs, and 13% had one CVD combined with other events. Of men who had a TED (n=1,589) 64% had one TED, 5% had several TEDs, and 31% had one TED combined with other events. When comparing demographic and tumor characteristics between those with 1, 2, or 3+ events after CaP diagnosis, there were no clear differences between patients. Multiple events occurred after all types of primary events, but more men had a HD prior to CaP diagnosis in the group with 2 or 3+ events than those with 1 event (36, 48, and 28%, respectively).
They conclude that among the 25% of men having one event, about one-third have a second event. Apart from a history of similar adverse events prior to CaP diagnosis, no particular variables were found for men who experienced multiple events.
Presented by Jan Adolfsson, MD, et al. at the 26th Annual European Association of Urology (EAU) Congress - March 18 - 21, 2011 - Austria Centre Vienna, Vienna, Austria