Increased serum total creatine kinase and creatine kinase isoenzyme MB after cryosurgical ablation of the prostate.

Purpose: Several reports have documented that the MB isoenzyme of creatine kinase is present in prostatic tissue. However, since it has been shown that lower urinary tract manipulations, including transurethral prostatectomy, do not significantly increase serum creatine kinase isoenzyme MB levels, such elevations, which are found in patients after prostatic surgery, are believed to be specific for myocardial infarction. We examined whether cryosurgical ablation of the prostate altered serum creatine kinase or isoenzyme MB levels.

Materials And Methods: In 81 consecutive patients undergoing routine cryosurgical ablation of the prostate serum levels of creatine kinase and creatine kinase isoenzyme MB were measured from peripheral blood specimens drawn preoperatively, in the recovery room and at 8 and 24 hours postoperatively. Postoperative electrocardiograms were compared to the preoperative study.

Results: In 72 of 81 patients (89%) significant elevations in creatine kinase and creatine kinase isoenzyme MB levels were noted at all time points after cryosurgical ablation of the prostate and appeared to reach a peak at 16 hours postoperatively. The mean increases within the first 8 hours after cryosurgical ablation of the prostate were 1,355 units per 1. for creatine kinase and 46.6 ng./ml. for creatine kinase isoenzyme MB. No patient had any significant changes on the postoperative electrocardiogram. All 9 patients (11%) who did not have significant creatine kinase or creatine kinase isoenzyme MB levels after cryosurgery had undergone prior cryosurgery or combined radiation and hormonal therapy.

Conclusions: Cryosurgical ablation of the prostate appears to produce elevations in serum creatine kinase and creatine kinase isoenzyme MB, which are specific to the procedure. Assays for creatine kinase isoenzyme MB are unreliable to render a diagnosis of myocardial infarction after cryosurgical ablation of the prostate.