Prospective trial of cryosurgical ablation of the prostate: five-year results.

OBJECTIVES: To determine in a prospective pilot study the safety and efficacy of cryosurgical ablation for localized prostate carcinoma. METHODS: A total of 87 cryosurgical procedures were performed on 76 consecutive patients between December 1994 and February 1998. All patients had histologically proved adenocarcinoma of the prostate, with prostate-specific antigen (PSA) readings of less than 30 ng/mL. Clinical evaluations, PSA determinations, and patient self-reported quality-of-life questionnaires (functional assessment of cancer treatment-prostate; FACT-P) were used to determine biochemical and clinical disease-free status and complications. Patients had a mean follow-up of 50 months (minimum 36). RESULTS: Follow-up biopsies were performed in 73 patients, and 72 were negative for malignancy after one or more treatments. Ten patients required two treatments and 1 patient required three treatments. The 5-year overall and cancer-specific survival rate was 89% (95% confidence interval, 83% to 97%) and 98.6% (95% confidence interval, 96% to 100%), respectively. The undetectable PSA rate (less than 0.3 ng/mL) for low-risk patients (n = 13) was 60% at 5 years; for moderate-risk patients (n = 23), it was 77%, and for high-risk patients (n = 40), 48%. The corresponding percentage of patients with a PSA level less than 1.0 ng/mL at 5 years was 75%, 89%, and 76%. Sloughing occurred in 3 patients (3.9%), incontinence in 1 (1.3%), and testicular abscess in 1 (1.3%). At 3 years, 18 (47%) of 38 patients capable of unassisted intercourse at the time of cryosurgery had resumed sexual intercourse, 5 spontaneously and 13 with sildenafil or prostaglandin. CONCLUSIONS: The results of this prospective evaluation show cryosurgery to be both a safe and an effective option in the treatment of localized prostate cancer.

Histological findings in the prostate two years following cryosurgical ablation.

We examined the pathological findings from prostatic whole mounts obtained at post-mortem, 2 years following cryosurgical ablation of the prostate (CSAP), to evaluate the presence or absence of residual benign or malignant tissue. Whole prostates were obtained from two patients at post-mortem, in which the cause of death was not related to prostate cancer. The patients had received CSAP 24 and 30 months earlier, as the primary treatment for prostate cancer. Complete ablation of the gland was demonstrated in one case, with some residual viable benign glands in the transitional zone in the second case. These results suggest that localized prostate cancer can be successfully eradicated by CSAP.

Extraprostatic biopsy improves the staging of localized prostate cancer.

OBJECTIVE: To evaluate the role and safety of biopsy of the seminal vesicles and neurovascular bundles in determining the pathologic stage of prostatic carcinoma. METHODS: Eighty-one consecutive patients were enrolled in a comprehensive cryosurgical biopsy protocol that included sextant intraprostatic plus extraprostatic biopsy. The pathologic stage, determined after biopsy, was compared with the clinical stage, determined by digital rectal examination (DRE) and transrectal ultrasonographic (TRUS) evaluation. As well, complication rates for these patients were compared with rates for a separate group that underwent sextant intraprostatic biopsy alone. RESULTS: Of the 81 patients, 61 (75%) were confirmed to have cancer by biopsy. None of these patients was considered to have extraprostatic extension by clinical evaluation (DRE and TRUS), but 16 of 61 (26%) were identified to have extraprostatic cancer in the seminal vesicles (8 of 61, 13%) or in the neurovascular bundles (8 of 61, 13%) by extraprostatic biopsy. There was no significant difference in the complication rates between sextant intraprostatic biopsy and sextant intraprostatic plus extraprostatic biopsy (p>0.97). CONCLUSIONS: Extraprostatic biopsy identifies extension of carcinoma in a large proportion of patients in whom clinical evaluation by DRE and TRUS indicates organ-confined disease. Extraprostatic biopsy is therefore warranted as routine evaluation before surgery in order to correctly stage prostatic carcinoma and select appropriate therapy.

Outcome and safety of transrectal US-guided percutaneous cryotherapy for localized prostate cancer.

OBJECTIVES: To assess the effectiveness and safety of ultrasound (US)-guided cryotherapy as a primary treatment for localized prostate cancer. MATERIALS AND METHODS: A prospective study of percutaneous transrectal US (TRUS)-guided cryotherapy was performed on 71 patients with T1-T3, N0, M0 prostatic cancer: 10 patients underwent two or more procedures. All cases were newly diagnosed and patients had no previous treatment for cancer. For all patients, TRUS biopsies were performed at 5-6 months. Patients were monitored at 6 weeks; 3, 6, 9, and 12 months; and twice yearly thereafter for prostate specific antigen (PSA) levels, complications, and clinical evidence of residual disease. RESULTS: Follow-up from 10 to 36 months was available for 70 of 71 patients; one patient died of unrelated disease. Initially, 10 of 69 patients had positive postcryotherapy biopsy results. After repeated treatment, nine of these 10 patients had negative biopsy results and one patient had no follow-up. Overall, 68 of 69 patients had negative biopsy results. At 1 year, 43 of 64 (67%) had an undetectable PSA level. Two patients had proven metastases. Complications include three cases with urethral sloughing requiring transurethral resection of the prostate (TURP). One patient had orchitis. Two patients had persistent incontinence, one as the result of a TURP. There was no death, acute serious morbidity, or fistula formation. Impotence was universal at 6 months, but many patients demonstrated late recovery. CONCLUSION: Cryoablation is an imaging-guided percutaneous intervention for prostate cancer that can safely yield disease-free status in a high percentage of patients with localized disease.

Correlation between thermosensor temperature and transrectal ultrasonography during prostate cryoablation.

OBJECTIVE: To determine if the adequacy of freezing in the neurovascular bundle region of the prostate during prostate cryotherapy can be monitored by transrectal ultrasonography (TRUS). PATIENTS AND METHODS: The study group consisted of 11 patients undergoing TRUS-guided prostate cryotherapy. The actual temperature in the gland was monitored with thermosensors placed in each prostatic neurovascular bundle. The 2 cryo-operators, working together and blinded to the actual temperature, used sonographic observations to estimate the temperature at the neurovascular bundles every 2 minutes until they believed that the gland was adequately frozen. The congruity between the estimated and measured temperatures was analyzed to determine if the operators could accurately monitor the progress of cryoablation by ultrasonography. RESULTS: There were a total of 85 data points for which the operators thought tumoricidal cryo-injury had been achieved at the neurovascular bundles (temperature -20 degrees C or below). For these points the measured temperature was on average 6.0 degrees C warmer than the estimated temperature (standard deviation, 22). For operator estimates of -20 degrees C or below, the measured temperature was -20 degrees C or below for 37 (44%) data points, between -19 degrees C and 0 degree C for 32 (38%) and greater than 0 degree C for 16 (19%). CONCLUSIONS: The operators were not able to accurately predict subzero temperatures at the neurovascular bundle region by TRUS evaluation. Moreover, the bias and magnitude of the error were significant and might lead to inadequate freezing of the prostate during attempted cryoablation.

Prostatic cryosurgery: use of MR imaging in evaluation of success and technical modifications.

PURPOSE: To evaluate the usefulness of contrast material-enhanced magnetic resonance (MR) imaging in objective assessment of prostatic cryosurgery and the role of MR imaging in the modification of prostatic cryosurgical technique. MATERIALS AND METHODS: Thirty-eight consecutive patients with localized (T1-3, N0, M0) prostatic adenocarcinoma treated with prostatic cryosurgery underwent MR imaging without contrast enhancement before cryosurgery and unenhanced and gadolinium-enhanced MR imaging within 1-3 weeks after cryosurgery. The first 20 patients also underwent MR imaging at 3 months after cryosurgery. MR imaging findings were correlated with those from transrectal ultrasound-directed prostatic staging biopsy. RESULTS: Cryonecrotic prostate was identified as avascular regions characterized by absolute signal void on contrast-enhanced images. With progressive modification of cryosurgical technique, complete cryoablation of the prostate was achieved in the latter nine of the 38 patients. When cryoablation was considered complete according to MR imaging criteria, findings invariably correlated with those at biopsy, with no residual prostate tissue or tumor. CONCLUSION: Gadolinium-enhanced MR imaging of the prostate after cryosurgery provides a highly accurate means of monitoring success. Objective MR imaging findings allow modifications to the technology and technique, resulting in optimal therapeutic results with prostatic cryosurgery.

Prognostic factors in colorectal carcinoma of young adults.

To determine why the prognosis for colorectal cancer in young adults is poor, survival and prognostic factors in patients under 40 years of age were compared with those in patients between 40 and 50 years of age. In a 10-year period, 122 patients less than 50 years of age (88 between 40 and 50 years) presented at the Victoria General Hospital in Halifax, NS, with colorectal cancer. Their charts were retrospectively reviewed. Follow-up was obtained for all patients. Of the 34 patients younger than 40 years, 71% (24) were men compared with 38% (33) of older patients. Symptoms, their duration and the location of primary tumours were similar in the two groups. Patients younger than 40 years presented with advanced lesions (Dukes' stages C and D) in 67% of cases compared with 52% of the older group. Mucinous tumours were twice as common in patients less than 40 years old (p = 0.036) and actuarial survival rates were lower at all stages for the same group. The authors conclude that the poorer prognosis in patients less than 40 years of age is not due to late symptom reporting or delay in diagnosis, but to more aggressive disease.