I think that is a good question IMO and one I've asked my doctors.
I had a chunk of squamous cell carcinoma taken out of my leg about 8 years ago. They believe they got it all. I asked at the time if I had the propensity for more cancer. The answer was no, yet here I am with prostate cancer.
Lower left groin hernia:
mesh and large scar: surgery early 2006
Nov/Dec 07 and March 08 and now Dec 08: Severe perineal pain (between scrotum and rectum). Septra/Bactrim for 8 months (Nov 07-Jun 08) for diagnosed prostatitis.
PSA start of 2008: 5.3..... PSA June of 2008: 7.3
14 DRE all benign or nothing felt
TRUS Biopsy Nov 08: Got copy of pathology (see below). Prostate about 40 cm sq.
General Health: pretty good, 5' 10", 180 lbs, slim.
Bone scan Dec 08: Negative
Barium enema X-ray (March 09 due to several days of blood in stool)
MRI with endorectal coil (April 09 as part of a study)
3D advanced TRUS (April 09 as part of a study)
CT (April 09 as part of a study)
Biopsy Pathology: 5 of 8 cores positive, adenocarinoma in both lobes. 30%-65%. One core perineural invasion. 2 cores "foamy" and suspicious. All +ve cores, 3+3 GS 6.
Open RP surgery: May 5/09 Surgeon spoke to my wife and was very positive. Said both nerve bundles spared and not damaged. Bilateral lymph node dissection performed. Discharged 48 hours after surgery. Staples out, catheter out and pathology sheduled for May 21.
Physical State: Home office in basement. Up and down 10-20 times a day. Walking lots of circles around inside of house and back patio. Bit sore but coping very well so far.
Mental State: Pre-surgery anxiety gone. Now waiting for path report, cath removal and staples out.