Active Surveillance with Selective Delayed Intervention for Favourable Risk Prostate Cancer: Clinical Experience and a “Number Needed to Treat” Analysis

Active surveillance for favorable-risk prostate cancer: a short review

Active surveillance is becoming a more widely accepted management strategy in men with low-risk localized prostate cancer. This is in recognition of the knowledge that most men with such cancer are likely to die from other causes. The obvious benefits of active surveillance are reduced morbidity by delaying or avoiding radical gland therapy. These advantages should be balanced against appropriate selection criteria and triggers for moving to radical therapy while on active surveillance. The optimal method by which to identify the small number of men who will progress by use of clinical, biopsy, and imaging data is yet to be defined. Nevertheless, active surveillance is an appealing management option in selected men with prostate cancer and represents a solution to the significant problem of the overdiagnosis of clinically insignificant disease that accompanies prostate-specific antigen (PSA) screening.

Development of a new method for monitoring prostate-specific antigen changes in men with localised prostate cancer: a comparison of observational cohorts

BACKGROUND

Prostate-specific antigen (PSA) measurements are increasingly used to monitor men with localised prostate cancer (PCa), but there is little consensus about the method to use.

OBJECTIVE

To apply age-specific predictions of PSA level (developed in men without cancer) to one cohort of men with clinically identified PCa and one cohort of men with PSA-detected PCa. We hypothesise that among men with clinically identified cancer, the annual increase in PSA level would be steeper than in men with PSA-detected cancer.

DESIGN, SETTING, AND PARTICIPANTS

The Scandinavian Prostate Cancer Group 4 (SPCG-4) cohort consisted of 321 men assigned to the watchful waiting arm of the SPCG-4 trial. The UK cohort consisted of 320 men with PSA-detected PCa in the Prostate testing for cancer and Treatment (ProtecT) study who opted for monitoring. Multilevel models describing changes in PSA level were fitted to the two cohorts, and average PSA level at age 50, change in PSA level with age, and predicted PSA values were derived.

MEASUREMENTS

PSA level.

RESULTS AND LIMITATIONS

In the SPCG-4 cohort, mean PSA at age 50 was similar to the cancer-free cohort but with a steeper yearly increase in PSA level (16.4% vs 4.0%). In the UK cohort, mean PSA level was higher than that in the cancer-free cohort (due to a PSA biopsy threshold of 3.0 ng/ml) but with a similar yearly increase in PSA level (4.1%). Predictions were less accurate for the SPCG-4 cohort (median difference between observed and predicted PSA level: -2.0 ng/ml; interquartile range [IQR]: -7.6-0.7 ng/ml) than for the UK cohort (median difference between observed and predicted PSA level: -0.8 ng/ml; IQR: -2.1-0.1 ng/ml).

CONCLUSIONS

In PSA-detected men, yearly change in PSA was similar to that in cancer-free men, whereas in men with symptomatic PCa, the yearly change in PSA level was considerably higher. Our method needs further evaluation but has promise for refining active monitoring protocols.

Uncertainty and quality of life among men undergoing active surveillance for prostate cancer in the United States and Ireland

BACKGROUND

Prostate cancer continues to be the most common site of male cancers, particularly among older men in Europe and the United States, and the second most common male cancer worldwide. Active surveillance involves the use of no local or systemic therapy once prostate cancer has been diagnosed. A description of uncertainty and quality of life among men undergoing active surveillance in samples from both the United States and Ireland has the potential to enhance global health care delivery.

METHODS

The specific aim of this study is to enhance the understanding of the experience of active surveillance for prostate cancer among Irish and American men by measuring quality of life and levels of uncertainty among men over the age of 65 in receipt of the active surveillance management option for prostate cancer. A quantitative, descriptive survey design was used.

RESULTS

Twenty-nine men completed questionnaires. The results reveal that men undergoing active surveillance in the United States have slightly higher levels of uncertainty. Primary appraisal, opportunity, and danger appraisal were consistent between samples from both countries. Total affective and health-related quality-of-life scores were similar among active surveillance participants in both countries, but subscale scores identified both similarities and differences. Irish men had lower mean role and social function than U.S. men, and higher general health and energy. Irish men reported more urine bother and less sexual bother than U.S. men.

CONCLUSION

To assist men with prostate cancer who are treated with the active surveillance management option, health care professionals must develop an awareness of how prostate cancer affects the man's physical and psychological health care outcomes.

Energy-based ablative therapy of prostate cancer: high-intensity focused ultrasound and cryoablation

PURPOSE OF REVIEW

This review is an update on the role of the two minimally invasive techniques in primary therapy of organ-confined prostate cancer: as a salvage option after standard-therapy failure and for focal ablation of index tumors.

RECENT FINDINGS

Energy-based ablative techniques are of growing interest for today's heterogeneous spectrum of prostate cancer. At present, primary high-intensity focused ultrasound appears to be a valid alternative to active surveillance protocols in low-risk cancers and, in older patients, to standard therapy. Morbidity is low, although postoperative impotence occurs frequently. Cryoablation has higher morbidity, even with third-generation conformal technology. With radiorecurrent cancer the potential radiation damage of the rectal wall renders transrectal high-intensity focused ultrasound more hazardous. Third-generation cryoablation seems to give better cancer control with lower morbidity in this situation. Unfortunately, long-term outcome data from controlled trials are not available.

SUMMARY

These minimally invasive techniques are not magic bullets, and patients must be informed accordingly. Focal ablation of the prostate segment with the index cancer would minimize morbidity and therefore appears highly appealing. Its success depends on correct localization of the lesion. Until this is achieved with sufficient reliability by appropriate biopsy or imaging techniques it remains strictly experimental.