Focal Therapy in Prostate Cancer E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 278

Veröffentlichungsjahr: 2011

Beschreibung

This book comprehensively reviews the potential of focal therapy and discusses why the changing face of prostate cancer warrants a change in the way we treat men with the disease. It deals with the mechanisms by which disease can be localized within the gland and then the different technologies used for focal ablation. Bringing together eminent contributors in one accessible reference, this book introduces focal therapy to all urologists, oncologists, and radiologists who are involved in the treatment of men with prostate cancer.

Leseprobe

Contents

Cover

Title Page

Copyright

Contributor List

Preface to the first edition

Section I: Is there a role for Focal Therapy in Localised Prostate Cancer?

Chapter 1: The Rationale for Focal Therapy of Prostate Cancer

Introduction

The therapeutic dilemma

Cost

Conservative management

Minimally invasive therapies

Focal therapy—the middle way?

Conclusion

Chapter 2: Factors That Affect Patients’ Choice of Treatment

Introduction

Factors influencing patient choice

Conclusion

Chapter 3: Histological Trends and the Index Lesion in Localized Prostate Cancer

Introduction

Multifocal, unifocal, and unilateral prostate cancer

The index tumor

Genetic studies on clonal origin of prostate cancer

Conclusion

Chapter 4: Selection Criteria for Prostate Cancer Focal Therapy

Introduction

Goals of therapy

Who is the ideal candidate?

Cure versus control: the concept of index lesion

Methods of mapping

Recommendations

Section II: How can we accurately locate cancer within the gland?

Chapter 5: Localization of Cancer within the Gland: Biopsy Strategies

Introduction

Transrectal biopsy strategies

Transperineal biopsy strategies

Conclusions

Chapter 6: Localization of Cancer within the Gland: Ultrasound Imaging

Introduction

Elastography

Doppler and contrast-enhanced ultrasound

Sonohistology

Conclusion

Chapter 7: Localization of Cancer within the Prostate: Dynamic Contrast-Enhanced MRI

Introduction

Pathophysiological basis

Enhancement analysis

Acquisition techniques

Cancer detection

Conclusion

Chapter 8: Localization of Cancer within the Gland: Diffusion-Weighted Magnetic Resonance Imaging of the Prostate

Introduction

Methodology

Utility of prostate DW—MRI in the clinic

Summary

Acknowledgments

Chapter 9: The Future of Molecular and Biomolecular Imaging in Prostate Cancer

Introduction

Molecular imaging methods

Applications

Conclusions

Section III: How can we create discrete tissue necrosis?

Chapter 10: Energies for Focal Ablation: Cyroablation

Introduction

Cryobiology

Clinical reports of organ-preserving prostate cryoablation

Conclusions

Chapter 11: Focal Salvage Cryoablation in Recurrent Prostate Cancer

Introduction

Preoperative evaluation and patient selection

Operative technique

Oncological effect

Complications

Conclusions

Chapter 12: High-Intensity Focused Ultrasound

Introduction

HIFU devices

Focal therapy series

Conclusion

Chapter 13: Energies for Focal Ablation: Photodynamic Therapy

Introduction

Mechanism of action

Technique of prostate photodynamic therapy

Preclinical studies

Clinical studies of PDT for prostate cancer

Clinical work in primary prostate cancer

Use of PDT in focal treatment of prostate cancer

Chapter 14: Focal Therapy for Prostate Cancer Using Radiation

Introduction

Brachytherapy

External beam irradiation

Conclusion

Chapter 15: Image Registration and Fusion for Image-Guided Focal Ablation

Introduction

Registration versus fusion

Accuracy validation

Future work

Section IV: How can we determine the success of Focal Therapy?

Chapter 16: Determining Success of Focal Therapy: Biochemical and Biopsy Strategies

Introduction

Defining biochemical recurrence

Determining histological local recurrence

Creating a responsible and pragmatic follow-up strategy

Conclusion

Acknowledgment

Chapter 17: Determining Success of Focal Therapy: Imaging

Introduction

Real-time feedback in ablative techniques

Early assessment of necrosis: verification

Six months onward: detecting residual disease and monitoring for recurrence

Summary

Chapter 18: Evaluating Focal Therapy: Future Perspectives

Introduction

Pragmatic and adaptive trial design

Population

Intervention

Conclusion

Colour plate

Index

This edition first published 2012 © 2012 by Blackwell Publishing Ltd.

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Library of Congress Cataloging-in-Publication Data

Focal therapy in prostate cancer / edited by Hashim U. Ahmed ... [et al.]. p. ; cm. Includes bibliographical references and index. ISBN-13: 978-1-4051-9649-9 (hardcover : alk. paper) ISBN-10: 1-4051-9649-1 (hardcover : alk. paper) 1. Prostate–Cancer–Surgery. 2. Cancer–Diagnosis. I. Ahmed, Hashim Uddin. [DNLM: 1. Prostatic Neoplasms–surgery. 2. Ablation Techniques. 3. Neoplasm Staging. WJ 762] RC280.P7F63 2012 616.99′463–dc23 2011015318

A catalogue record for this book is available from the British Library.

This book is published in the following electronic formats: ePDF 9781444346862; Wiley Online Library 9781444346893; ePub 9781444346879; Mobi 9781444346886

Contributor List

Hashim U. Ahmed MRCS, BM, BCh, BA (Hons) MRC Clinician Scientist in Uro-Oncology Clinical Lecturer in Urology Division of Surgery and Interventional Sciences University College London London, UK

Clare Allen MD, FRCR, BM, BCh Consultant Radiologist Department of Radiology University College London Hospitals NHS Foundation Trust London, UK

Nimalan Arumainayagam MD Specialist Registrar in Urology Division of Surgery and Interventional Sciences University College London London, UK

Dean C. Barratt PhD Senior Lecturer in Medical Image Computing UCL Centre for Medical Image Computing University College London London, UK

Al B. Barqawi MD, FRCS Associate Professor of Surgery/Urology Director of Prostate Cancer Fellowship Program Division of Urology University of Colorado Denver School of Medicine Aurora, CO, USA

Winston E. Barzell MD, FRCS, FACS Clinical Assistant Professor FSU College of Medicine Urology Treatment Center Sarasota, FL, USA

Nacim Betrouni PhD INSERM University of Lille Nord de France Lille, France

Michael D. Brundage MSc, FRCPC, MD Professor Department of Oncology and Department of Community Health and Epidemiology Queen's University; and Radiation Oncologist Cancer Centre of Southeastern Ontario Kingston, ON, Canada Director Division of Cancer Care and Epidemiology Cancer Research Institute Queen's University Kingston, ON, Canada

Peter R. Carroll MD, MPH Professor and Chair Department of Urology UCSF Helen Diller Family Comprehensive Cancer Center University of California, San Francisco San Francisco, CA, USA

Pierre Colin MD Chef de clinique Assistant Department of Urology CHRU Lille, University of Lille Nord de France Lille, France

Matthew Cooperberg MD, MPH Assistant Professor Department of Urology UCSF Helen Diller Family Comprehensive Cancer Center University of California, San Francisco San Francisco, CA, USA

E. David Crawford MD Professor of Surgery/Urology/Radiation Oncology Head Urologic Oncology E. David Crawford Endowed Chair in Urologic Oncology University of Colorado, Denver Aurora, CO, USA

Cole Davis MD Clinical Oncology Fellow Department of Urology UCSF Helen Diller Family Comprehensive Cancer Center University of California, San Francisco San Francisco, CA, USA

Nandita M. deSouza BSc, MBBS, MD, FRCP, FRCR Professor of Translational Imaging Institute of Cancer Research and Royal Marsden Hospital London, UK

Mark Emberton FRCS (Urol), FRCS, MD, MBBS, BSc Professor of Interventional Oncology and Honorary Consultant Urological Surgeon Division of Surgery and Interventional Science University College London London, UK

NIHR UCL/UCH Comprehensive Biomedical Research Centre London, UK

Deb Feldman-Stewart PhD Cognitive Psychologist Division of Cancer Care and Epidemiology Cancer Research Institute Queen's University Kingston, ON, Canada

Professor Department of Oncology Queen's University Kingston, ON, Canada

Elizabeth M. Genega MD Staff pathologist Beth Israel Deaconess Medical Center Boston, MA, USA

Assistant Professor Harvard Medical School Boston, MA, USA

Michael S. Gee MD, PhD Assistant Radiologist Abdominal Imaging and Interventional Radiology Massachusetts General Hospital Harvard Medical School Boston, MA, USA

Assistant Professor The University of Texas MD Anderson Cancer Center Houston, TX, USA

David J. Hawkes PhD, CPhys, FMedSci, FREng, FInstP, FIPEM Director of the UCL Centre for Medical Image Computing University College London London, UK

Mukesh G. Harisinghani MD Director of Abdominal MRI Associate Professor of Radiology Department of Radiology Harvard University Boston, MA, USA

Timothy K. Ito Resident in Urology Division of Urologic Oncology Department of Urology New York University Langone Medical Center New York, NY, USA

Rajat K. Jain Resident in Urology New York University Langone Medical Center School of Medicine New York, NY, USA

Irving Kaplan MD Assistant Professor Radiation Oncology Harvard Medical School Boston, MA, USA

Beth Israel Deaconess Medical Center Boston, MA, USA

Alex Kirkham BM, BCh, FRCS, FRCR, MD Consultant Radiologist Department of Radiology University College London Hospitals NHS Foundation Trust London, UK

Laurent Lemaitre MD, PhD Professor Department of Radiology University of Lille Nord de France Lille, France

Paul D. Maroni MD Assistant Professor Division of Urology Department of Surgery University of Colorado School of Medicine Aurora, CO, USA

Caroline M. Moore MD, MRCS (Ed) Clinical Lecturer in Urology University College London and University College London Hopsitals NHS Trust London, UK

Vladimir Mouraviev MD Clinical Fellow Instructor Urology Division Department of Surgery University of Cincinnati College of Medicine Cincinnati, OH

Anwar Padhani MBBS Consultant in Radiology Paul Strickland Imaging Centre Mount Vernon Cancer Centre Northwood, Middlesex, UK

Rodrigo Pinochet MD Urologic Oncology Fellow Memorial Sloan-Kettering Cancer Center New York, NY, USA

Associate Instructor Department of Urology Pontificia Universidad Catolica de Chile Santiago, Chile

Louis L. Pisters MD Professor of Urology The University of Texas MD Anderson Cancer Center Houston, TX, USA

Thomas J. Polascik MD, FACS Director of Urologic Oncology Duke Cancer Institute Duke University Medical Center Durham, NC, USA

Philippe Puech MD, PhD Associate professor of Radiology CHRU Lille University of Lille Nord de France Lille, France

INSERM University of Lille Nord de France Lille, France

Neil Rofsky MD Professor of Radiology Department of Radiology Beth Israel Deaconess Medical Center Boston, MA, USA

Sophie F. Riches MPhys Msc Clinical Physicist Institute of Cancer Research and Royal Marsden Hospital London, UK

Ulrich Scheipers PhD TomTec Imaging Systems GmbH Unterschleissheim, Germany Ruhr-University Bochum, Bochum, Germany

Katsuto Shinohara MD Helen Diller Family Chair in Clinical Urology Professor, Department of Urology and Radiation Oncology University of California, San Francisco San Francisco, CA, USA

Samir S. Taneja MD James M. Neissa and Janet Riha Neissa Associate Professor of Urologic Oncology Director, Division of Urologic Oncology Department of Urology GU Program Leader, New York University Cancer Institute New York University Langone Medical Center New York, NY, USA

Chief Urology Section Veterans Administration New York Harbor Healthcare System (Manhattan campus) New York, NY USA

Nina Tunariu MD Specialist Registrar in Radiology Institute of Cancer Research and Royal Marsden Hospital London, UK

Arnauld Villers MD, PhD Professor in Urology Department of Urology CHRU Lille, University of Lille Nord de France Lille, France

John F. Ward MD, FACS Assistant Professor Department of Urology The University of Texas MD Anderson Cancer Center Houston, TX, USA

Thomas M. Wheeler MD Harlan J. Spjut Professor and Chair Department of Pathology and Immunology Baylor College of Medicine Houston, TX, USA

Preface to the first edition

The diagnostic and therapeutic landscape of prostate cancer is one of the most exciting areas of medical research in our modern age. Very few conditions or diseases have caused as much controversy and debate in the medical and popular literature. The manner in which we currently diagnose and treat prostate cancer seems to lead to ever increasing cost to the individual patient, to his family, and to healthcare systems in general, but with great uncertainty over the benefits. The entire pathway has come into question, based as it is on inherent inaccuracy and lack of precision in locating, targeting, and treating the malignant tumor. Almost all other solid organ cancers rely on visualizing the cancer, sampling it accurately, and delivering therapy only to that area which requires it.

Focal therapy in prostate cancer supports a similar, albeit belated, paradigm shift. Such a change relies on accurate imaging, accurate biopsy, and accurate destruction of the cancer while minimizing collateral damage and preserving as much normal tissue as possible. What are the benefits? We may have an isoeffective treatment that carries less harm to the individual man in a more cost-effective way that benefits society. The challenges are tremendous—locating cancers in a walnut-sized organ is not easy—ablating areas to millimeter accuracy and ensuring the remainder of the tissue does not develop new cancers which progress into life-threatening disease. This book is written by international experts at the forefront of imaging and focal therapy of prostate cancer and will provide the reader with a comprehensive scientific approach to the aspirations and challenges of focal therapy.

Hashim U. AhmedManit AryaPeter CarrollMark EmbertonNovember 2011

SECTION I

Is there a role for Focal Therapy in Localised Prostate Cancer?

Chapter 1

The Rationale for Focal Therapy of Prostate Cancer

Cole Davis MD, Matthew Cooperberg MD MPH, and Peter R. Carroll MD MPH

Department of Urology, UCSF Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA

Introduction

The goals of cancer therapy are either to prevent, cure, or control disease while minimizing the side effects of treatment. One must balance the number of life years gained (quantity) with the morbidity of a given treatment technique (quality). The ultimate goal is to match treatment type with the biological aggressiveness of the disease in an individual patient. A difficult initial hurdle is predicting disease aggressiveness. Nomograms and other risk-prediction instruments incorporating multiple pathologic, laboratory, and clinical measures have become the cornerstone in prostate cancer risk assessment. Accurate risk assessment guides treatment. In contemporary practice there is a continuing movement toward maximizing survival while minimizing morbidity.

This movement is seen clearly when examining the increasing use of laparoscopic and, more recently, robot-assisted laparoscopic techniques in the treatment of prostate and renal cancers as well as conformal and intensity-modulated radiation therapy (IMRT), cryotherapy, brachytherapy, and experimental modalities such as high-intensity focused ultrasound (HIFU) and photodynamic therapy in the treatment of prostate cancer. Minimally invasive techniques that deliver therapy to the cancer alone, with a margin of normal tissue, are attractive since the risks of local progression and thus metastasis are, at least in theory, decreased compared to surveillance, while the morbidity associated with radical resection or whole-organ ablation decreased.

The therapeutic dilemma

The morbidity associated with radical prostatectomy and radiotherapy is well described and is primarily a result of treatment effects on adjacent structures [1]. Overall, each of the whole-gland radical treatments can be associated with significant morbidity. Radiotherapy causes short-term moderate bowel and urinary toxicity in almost 50% with most having limited toxicity. However, 5–20% with bowel toxicity have long-term persistence. Select surgical series report as high as 27% risk of chronic urinary symptoms. Both radiotherapy and surgery have a near 50% reduction in sexual function, though the reports are widely variable. Additionally, newer techniques and increasing refinement in technology have shown very little change in the toxicity profiles [2].

Therefore, minimally invasive techniques applied to discreet tumor areas, rather than the whole gland, stand to modify treatment impact the most with regard to urethral, rectal, and cavernosal nerve injury. Additional advantages could include reduced hospital stay and earlier return to work. Prostate cancer is biologically unique given the indolent nature and protracted natural history of many lesions. This demands individualized treatment decisions that include active surveillance or active treatment currently in the form of whole-gland therapy. Although the trend is changing in recent years as more compelling data becomes available, few patients elect to defer initial treatment. Between 1989 and 2008, 11,892 men with localized prostate cancer were registered in the CaPSURE multi-institutional database, and of those, only 810 (6.8%) elected to defer treatment and be managed with watchful waiting or active surveillance [3]. The rationale for use of minimally invasive therapies must be based on the following principles:

1. The technique offers similar disease control compared to the current options.

2. It is less morbid.

3. It offers improved outcomes compared to patients managed conservatively.

4. The technique is cost effective.

Prostate cancer has significant mortality worldwide, yet has an incidence-to-mortality ratio of 8.6 in the United States, 3.0 in the United Kingdom, and 1.2 in Africa [4]. Such differences may reflect many factors, one of which is screening rates. This is supported by multiple autopsy series showing that 30–40% of men suffering nonprostate cancer related deaths harbor prostate cancer [5]. Additionally, incidental prostate cancer is found in 23–45% of men undergoing cystoprostatectomy for the management of bladder cancer.

The difficult choices faced by men who have localized prostate cancer are further confounded by the findings from the recent publication of the third interim analysis from the European Randomized Study of Screening for Prostate Cancer (ERSPC). This demonstrated a reduction in prostate cancer specific mortality from PSA screening and treatment [6]. However, the healthcare policy implications of screening need to be tempered. First, a randomized controlled study in the United States has shown no difference between PSA screening and control [7], although the control arm had a high degree of contamination since many men had already undergone a PSA test prior to enrolment. Second, there are considerable harms associated with a screening strategy. These include overtreatment and treatment-related harms. The ERSPC showed that 1410 men need to be screened and 48 diagnosed and treated in order that one prostate cancer related death is avoided over a 9-year interval. Overtreatment becomes less of a problem if the treatment is cost effective and associated with very low rates of harm, while eliminating potentially high-risk disease.

Cost

The cancer-attributable costs associated with the first 6 months of treatment in 1999 demonstrated that radical prostatectomy cost $8113, external beam radiotherapy cost $6116, and brachytherapy cost $7596 [8]. Another study from the same time period found mean hospital charges of $5660 for radical prostatectomy compared to $4150 for cryotherapy. Most of the cost savings for cryotherapy arise from hospitalization costs of $2348 for radical prostatectomy and $682 for cryotherapy [9]. Most cost analyses do not take into account lost productivity from multiple treatment visits required for radiation therapy or postoperative visits and urethral catheter time associated with surgery. Costs for newer forms of radiation such as IMRT and proton therapy are higher. Insurers and public interest groups are paying more attention to the costs of care in conjunction with their utility and wide variation in application [10,11]. Minimally invasive interventional techniques delivering focal therapy may have the advantage of being performed in a single, outpatient setting with fewer downstream costs of dealing with side effects, but this may need to be balanced with the rate of salvage therapies in the event of failure.

Conservative management

Active surveillance with the potential for delayed therapy must incorporate several elements:

1. Markers for disease progression are reliable.

2. Patients are compliant.

3. The cancer will not progress at a speed exceeding follow-up windows.

4. Treatment at the time of progression is effective.

5. Patients accept the potential anxiety associated with untreated cancer.

A meta-analysis including 828 patients on surveillance protocols found the risk of metastasis at 10 years after diagnosis in those with well-differentiated tumors to be 19% and cancer-specific mortality 13% [12]. Albertsen and colleagues have shown that many men with prostate cancer die of other diseases. Further, those with low-risk disease (well-differentiated tumors) managed conservatively can expect 10-year prostate cancer specific mortality of 8.3% [13]. Other studies suggest that men with prostate cancer may be at higher risk. Johansson et al. showed that cancer-specific survival dropped from 79% to 54%, as patients managed conservatively were followed past 15 years [14]. In addition, the Scandinavian prostate cancer group randomized trial of patients with localized prostate cancer in the pre-PSA era treated by radical prostatectomy or watchful waiting, revealed significant relative risk reductions in overall mortality, prostate cancer specific mortality, metastasis, and local progression in the former group. However, the benefit to treatment was seen in those less than 65 years of age. In addition, the patients in this trial were notably different than those currently detected with aggressive screening in the United States. For instance, only 12% had T1c disease and 20% had an initial PSA ≥20 ng/mL [15].

In the Toronto active surveillance cohort of 450 men overall survival was 78.6%. The 10-year prostate cancer actuarial survival was 97.2%. Overall, 30% had been reclassified as higher risk and offered definitive therapy [16]. The UCSF active surveillance series used stricter criteria and reflected a secondary treatment rate of 24% at 3-year median follow-up, although 37% met criteria for progression and 12% elected treatment without evidence of disease progression [17]. None have died in the UCSF series at a median follow-up of 3.6 years.

Minimally invasive therapies

Minimally invasive interventional techniques have been applied to whole-gland therapy for many years in order to find a middle ground between active surveillance and radical surgery or radiotherapy. The earliest such technique introduced for prostate cancer was radium brachytherapy in 1915. Another percutaneous technique is whole-gland cryotherapy. It shares many similar advantages with brachytherapy. Early outcomes using cryotherapy were worrisome with major complications reported such as urethrocutaneous and rectourethral fistula. Refinements in monitoring, urethral warming, and probe technology have brought about resurgence in interest in cryotherapy. A prospective randomized trial comparing cryoablation to external beam radiotherapy found near equivalent disease-free survival at 8 years and a significantly higher negative biopsy rate in those managed with cryoablation [18]. Katz et al. reviewed 5-year biochemical-free survival among patients treated with brachytherapy, conformal radiotherapy, radical prostatectomy, and whole-gland cryoablation in different series. When stratified according to low-, medium-, and high-risk disease, cryotherapy was equivalent to other modalities for low- and medium-risk patients and superior for high-risk patients [19]. The major disadvantage to whole-gland cryotherapy is the morbidity profile, most notably with regard to erectile dysfunction (approaching 100% in the whole-gland setting). Third generation, prostate cryoablation techniques have been in use since 2000 and have shown lower complication rates compared to previous techniques except for impotence. Reported complications include bladder outlet obstruction 3–21%, tissue sloughing 4–15%, and impotence 40–100% [20].

Other whole-gland techniques include HIFU and vascular-targeted photodynamic therapy (VTP). Early studies have yielded mixed results regarding efficacy and morbidity for these modalities [21]. For instance, HIFU whole-gland therapy seems to have incontinence rates (requiring pad usage) of less than 1%, impotence rates are still 20–50% [22]. However, application in a focal setting for well-selected patients may prove highly beneficial.

Focal therapy—the middle way?

Currently, minimally invasive modalities are receiving considerable interest applied as focal, rather than whole-gland, therapy [23,24]. Focal therapy involves the local application of therapy to a specific focus with a margin of normal tissue. Therapy can be applied ranging from a small focus to subtotal ablation thereby theoretically decreasing morbidity [25]. Several factors must be considered before focal therapy can be implemented as a routine option for early-stage prostate cancer. First, prostate cancer is often a multifocal disease. However, large studies have shown that between 10% and 44% of radical prostatectomy (RP) specimens harbor unilateral or unifocal cancers [26]. There is growing evidence that the majority of progression is driven by the size (>0.5 mL) and grade (Gleason ≥7) of the index tumor [27], and that most multifocal tumors outside the index lesion have a volume of <0.5 mL, making their clinical significance questionable. Some have argued that tumors <0.5 mL may not need immediate treatment [28], thus creating a large population of patients that may benefit from focal ablation of the index or unifocal tumor with subsequent surveillance of the smaller “clinically insignificant” lesions if present. (Figures 1.1a–h).

Figure 1.1 (a) Standard whole-gland strategies treat the entire prostate regardless of the risk category, volume, or disposition of cancer. (b–h) These figures illustrate the different strategies that could be employed using focal therapy to ablate either all areas of cancer or just the index lesion.

If focal therapy is to be considered, accurate localization of the index tumor is critical. Both improved biopsy as well as imaging techniques may allow for clearer and more accurate localization. Small prostate cancers have in the past proven to be very difficult to accurately detect radiographically, forcing most clinicians to rely on prostate biopsy to derive location and volume information. This trend is rapidly changing with improved imaging [29] and biopsy techniques such as transperineal template prostate mapping [30]. Given that benign PSA-producing tissue is spared with focal therapy, what constitutes appropriate cancer control measures (other than mortality) to be used in clinical trials is yet to be established. Composite definitions incorporating biochemical, histological, and imaging outcomes are likely to be needed until mature datasets demonstrate whether efficacy is maintained with respect to metastases and mortality [31].

Conclusion

Due to widespread screening, many contemporary prostate malignancies are small and focal in nature. Given the stage and tumor volume migration that has occurred, functional as well as cancer-specific outcomes are being critically assessed. Evidence is growing that novel techniques may offer similar disease control as the current “gold standards” while the treatment morbidity may be considerably less. Refinement and long-term assessment of the techniques described are critical if we are to better understand the role of such therapy in the management of prostate cancer.

References

1. Sandra MG, et al. Quality of life and satisfaction with outcome among prostate-cancer survivors. NEJM 2008;358: 1250.

2. Hu JC, et al. Comparative effectiveness of minimally invasive vs open radical prostatectomy. JAMA 2009;302(14): 1557–1564.

3. Cooperberg MR, Broering JM, Carroll PR. Time trends and local variation in primary treatment of localized prostate cancer. JCO 2010;28(7): 1117.

4. Kamangar F, et al. Patterns of cancer incidence, mortality, and prevalence across five continents: defining priorities to reduce cancer disparities in different geographic regions of the world. JCO 2006;24: 2137.

5. Konety BR, et al. Comparison of the incidence of latent prostate cancer detected at autopsy before and after the prostate specific antigen era. J Urol 2005;174: 1785.

6. Schröder FH, et al. ERSPC Investigators. Screening and prostate-cancer mortality in a randomized European study. NEJM 2009;360(13): 1320–1328.

7. Andriole GL, et al. PLCO Project Team. Mortality results from a randomized prostate-cancer screening trial. NEJM 2009;360(13): 1310–1319.

8. Zeliadt SB, et al. Trends in treatment costs for localized prostate cancer: the healthy screenee effect. Med Care 2007;45: 154.

9. Benoit RM, et al. Comparison of the hospital costs for radical prostatectomy and cryosurgical ablation of the prostate. Urology 1998;52(5): 820.

10. Greenberg D, et al. When is cancer care cost effective? JNCI 2010;102(2): 82–88.

11. Zietman A. Evidence-based medicine, conscience-based medicine, and the management of low-risk prostate cancer. JCO 2009;27(30): 4935–4936.

12. Chodak GW, et al. Results of conservative management of clinically localized prostate cancer. NEJM 1994;330(4): 242.

13. Lu-Yao GL, et al. Outcomes of localized prostate cancer following conservative treatment. JAMA 2009; 302: 1202.

14. Johansson JE, et al. Natural history of early, localized prostate cancer. JAMA 2004;291: 2713.

15. Bill-Axelson A, et al. Scandinavian Prostate Cancer Group Study Number 4. Radical prostatectomy versus watchful waiting in localized prostate cancer: the Scandinavian prostate cancer group-4 randomized trial. JNCI 2008;100(16): 1144–1154.

16. Klotz L. Active surveillance for prostate cancer: for whom? JCO 2005;23: 8165.

17. Dall’Era MA, et al. Active surveillance for the management of prostate cancer in a contemporary cohort. Cancer 2008; 112(12): 2664.

18. Donnelly BJ, et al. A randomized trial of external beam radiotherapy versus cryoablation in patients with localized prostate cancer. Cancer 2010;116(2): 323–330.

19. Katz A, Rewcastle JC. The current and potential role of cryoablation as a primary treatment for prostate cancer. Current reports. Oncol Rep 2003;5: 231.

20. Wilt TJ, et al. Systematic review: Comparative effectiveness and harms of treatments for clinically localized prostate cancer. Ann Intern Med 2008;148: 435.

21. Warmuth M, et al. Systematic review of the efficacy and safety of high-intensity focussed ultrasound for the primary and salvage treatment of prostate cancer. Eur Urol 2010;58(6): 803–815.

22. Ahmed HU, et al. Minimally-invasive technologies in uro-oncology: the role of cryotherapy, HIFU and photodynamic therapy in whole gland and focal therapy of localised prostate cancer. Surg Oncol 2009; 18(3): 219–232.

23. Ahmed HU, et al. Will focal therapy become a standard of care for men with localized prostate cancer? Nat Rev Clin Onc 2007;4(11): 632–642.

24. Lazzeri M, Guazzoni G. Focal therapy meets prostate cancer. Lancet 2010;376(9746): 1036–1037.

25. Ward JF, Jones JS. Classification system: organ preserving treatment for prostate cancer. Urology 2010;75(6): 1258–1260.

26. Karavitakis M, et al. Tumor focality in prostate cancer: implications for focal therapy. Nat Rev Clin Onc 2011;8(1): 48–55.

27. Wise AM, et al. Morphologic and clinical significance of multiple prostate cancers in radical prostatectomy specimens. Urology 2002; 60: 264.

28. Ahmed HU. The index lesion and the origin of prostate cancer. NEJM 2009;361(17): 1704–1706.

29. Ahmed HU, et al. Is it time to consider a role for MRI before prostate biopsy? Nat Rev Clin Oncol 2009; 6(4): 197–206.

30. Onik G, Barzell W. Transperineal 3D mapping biopsy of the prostate: an essential tool in selecting patients for focal prostate cancer therapy. Urol Oncol 2008;26(5): 506–510.

31. Ahmed HU, Emberton M. Benchmarks for success in focal therapy of prostate cancer: cure or control? World J Urol 2010;28(5): 577–582.

Chapter 2

Factors That Affect Patients’ Choice of Treatment

Deb Feldman-Stewart PhD1,2 and Michael D. Brundage MSc FRCPC MD1,2,3,4

1Division of Cancer Care and Epidemiology, Cancer Research Institute, Queen's University, Kingston, ON, Canada

2Department of Oncology, Queen's University, Kingston, ON, Canada

3Department of Community Health and Epidemiology, Queen’s University, Kingston, ON, Canada

4Cancer Centre of Southeastern Ontario, Kingston, ON, Canada

Introduction

Choosing a treatment for early-stage prostate cancer often presents a very complicated decision for men. There are many standard therapies available, including radical prostatectomy, external beam radiation, brachytherapy, and watchful waiting (instituting palliative treatment if required) or active surveillance (instituting radical treatment only if specific indications appear). The situation is further complicated by the poor quality of evidence around the relative efficacy and the relevant outcomes of each treatment option (Figure 2.1).

Figure 2.1 A diagram to illustrate how men choose between different therapies when diagnosed with localized prostate cancer.

Factors influencing patient choice

In this chapter, we are referring to information “factors,” the facts and opinions that may affect a patient's choice.

Side effects versus efficacy

Clinicians have an intuitive understanding that the chances of cure, balanced against the risks to bladder, bowel, and sexual function, are powerful factors influencing treatment choices of both patients and clinicians. In this chapter, we review this common medical paradigm of factors that relate to balancing potential benefit against potential harm, and highlight complexities related to this seemingly straight-forward consideration of competing outcomes. We then go on to show that this common paradigm (even acknowledging the complexities) is too limited in its approach to the decision, by identifying additional factors that patients often consider in making their choices.

Reviews of previous research on what factors influence patients choices in this decision agree that patients are motivated to have treatment to eradicate the cancer [1,2]. The reviews also report that patients do balance the potential benefit against possible harms, and consistent with clinicians’ intuitive understanding, the treatment's potential impact on bladder, bowel functioning, and sexual functions is central to their discussion. However, in their review, Zeliadt et al. suggest that there appears to be a disconnect between what side effects patients say are important and what actually influences their decisions. The reviewers note that data on the issue come from different types of studies, including qualitative and quantitative, prospective and retrospective studies. Sorting out how data from these different studies fit together is a challenge, but it does reveal that the factors that affect men's treatment decisions are not just a simple list that is suggested earlier.