About ASCRS Textbook of Colon and Rectal Surgery

Mahmoud N, Jafari MD, Ault G, Bordeianou L, Friel C, Hedrick T, Maykel JA, McGee MF, Wilkins K (Editors)

The ASCRS Textbook of Colon and Rectal Surgery
Copyright © 2025 American Society of Colon and Rectal Surgeons.

All rights reserved


Editors | Authors | Preface | Notices and Disclaimers


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Table of Contents

  1. Anatomy and Embryology of the Colon, Rectum, and Anus
  2. Colonic Physiology
  3. Anorectal Physiology
  4. Endoscopy
  5. Endoscopic Management of Polyps and Endolumenal Surgery
  6. Preoperative Evaluation in Colorectal Patients
  7. Optimizing Outcomes with Enhanced Recovery
  8. General Postoperative Complications
  9. Anastomotic Construction
  10. Anastomotic Complications
  11. Hemorrhoids
  12. Anal Fissure and Anal Stenosis
  13. Cryptoglandular Abscess and Fistula
  14. Rectourethral and Complex Fistulas: Evaluation and Management
  15. Rectovaginal Fistula
  16. Pilonidal Disease and Hidradenitis Suppurativa
  17. Dermatology and Pruritus Ani
  18. Sexually Transmitted Infections of the Colon and Rectum
  19. Anal Intraepithelial Neoplasia
  20. Anal Cancer
  21. Presacral Tumors
  22. Sporadic and Inherited Colorectal Cancer: How Epidemiology and Molecular Biology Guide Screening and Treatment
  23. Management of Malignant Polyps
  24. Colorectal Cancer: Preoperative Evaluation and Staging
  25. Colon Cancer Surgical Treatment: Principles of Colectomy
  26. Rectal Cancer: Neoadjuvant Therapy
  27. Rectal Cancer: Local Excision
  28. Rectal Cancer: Nonoperative Management
  29. Proctectomy for Rectal Cancer
  30. Colorectal Cancer: Postoperative Adjuvant Therapy and Surveillance
  31. Colorectal Cancer: Management of Distant Metastases
  32. Locally Recurrent Rectal Cancer
  33. Appendiceal Neoplasms
  34. Gastrointestinal Stromal Tumors, Neuroendocrine Tumors, and Lymphoma
  35. Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy
  36. Colorectal Cancer: Minimally Invasive Surgery
  37. Minimally Invasive Complete Mesocolic Excision with Extended Lymphadenectomy for Colon Cancer
  38. Colonic Diverticular Disease
  39. Large Bowel Obstruction
  40. Lower GI Hemorrhage
  41. Endometriosis
  42. Trauma of the Colon and Rectum
  43. Inflammatory Bowel Disease: Pathobiology
  44. IBD Diagnosis and Evaluation
  45. Medical Management of Ulcerative Colitis
  46. Medical Therapy for Crohn’s Disease
  47. Anorectal Crohn’s Disease
  48. Crohn’s Disease: Surgical Management
  49. Ulcerative Colitis: Surgical Management
  50. Complications of the Pelvic Pouch
  51. Infectious Colitis
  52. Clostridium difficile Infection
  53. Radiation, Microscopic, and Ischemic Colitis
  54. Intestinal Stomas
  55. Abdominal Wall Reconstruction and Parastomal Hernia Repair
  56. Functional Disorders After Colorectal Surgery/IBS
  57. Common Tests for the Pelvic Floor
  58. Evaluation of Constipation and Treatment of Abdominal Component
  59. Treatment of Difficult/Obstructive Defecation
  60. Rectal Prolapse
  61. Fecal Incontinence: Evaluation and Treatment
  62. Low Anterior Resection Syndrome (LARS)
  63. Sexual Function After Colorectal Surgery in Women
  64. Male Genitourinary Dysfunction as a Consequence of Colorectal Surgery
  65. Middle and Anterior Pelvic Compartment: Issues for the Colorectal Surgeon
  66. Pediatric Colorectal Disorders
  67. Considerations for Geriatric Patients Undergoing Colorectal Surgery
  68. Healthcare Economics
  69. Ethical Considerations (Conflict of Interest, Surgical Innovation, and End of Life)
  70. Welcome to Litigation
  71. Quality
  72. Practice Management

Editors

Najjia Mahmoud, MD
Division of Colon and Rectal Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA, USA

Mehraneh Dorna Jafari, MD
Department of Surgery, Weill Cornell Medicine, New York, NY, USA
Department of Colon and Rectal Surgery, New York Presbyterian Brooklyn Methodist Hospital, New York, NY, USA

Glenn T Ault, MD
Department of Colorectal Surgery, Keck Medicine of University of Southern Californ, Los Angeles, CA, USA

Liliana Bordeianou, MD, MPH
Pelvic Floor and Colorectal Surgery Centers, Massachusetts General Hospital, Boston, MA, USA

Charles Friel, MD
Department of Surgery, University of Virginia Medical Center, Charlottesville, VA, USA

Traci Hedrick, MD
Department of Surgery, University of Virginia Medical Center, Charlottesville, VA, USA

Justin A. Maykel, MD
Department of Surgery, University of Massachusetts Medical School, Worcester, MA, USA

Michael F. McGee, MD
Division of Colorectal Surgery, University of Michigan, Ann Arbor, MI, USA

Kirsten Wilkins, MD
Associated Colon & Rectal Surgeons, Atlantic Health System, Summit, NJ, USA

Authors

Maher A. Abbas, MD
King’s College Hospital, Dubai, UAE

Karim Alavi, MD, MPH
University of Massachusetts Medical School, Department of Surgery, Division of Colon and Rectal Surgery, Worcester, MA, USA

Dennis K. Ames , JD
Medical Malpractice Trail Attorney, Santa Ana, CA, USA

Jean H. Ashburn, MD
Wake Forest Baptist Health, Department of Surgery, Winston-Salem, NC, USA

Reza Askari, MD
Division of Trauma, Burns, Surgical Critical Care and Acute Care Surgery, Brigham and Woman’s Hospital, Harvard Medical School, Boston, MA, USA

Glenn T. Ault, MD, MSEd
University of Southern California – Keck School of Medicine, Department of Surgery, Division of Colorectal Surgery, Los Angeles, CA, USA

Kenneth S. Azarow, MD
Oregon Health Sciences University, Department of Surgery, Portland, OR, USA

Andrea Chao Bafford, MD
University of Maryland School of Medicine, Department of Surgery, Baltimore, , MD, USA

Jennifer S. Beaty, MD
Associate Dean for Graduate Medical Education, Des Moines University Medicine and Health Sciences, Des Moines, IA, USA

Willem A. Bemelman, MD, PhD
Amsterdam University Medical Centre, Location Meibergdreef, Department of Surgery, Amsterdam, Netherlands

Greta Bernier, MD
UW Medicine – Valley Medical Center, Department of Surgery, Renton, WA, USA

Anuradha R. Bhama, MD
Department of Colon and Rectal Surgery, Cleveland Clinic, Cleveland, OH, USA

Elisa Birnbaum, MD
University of Colorado Anschutz Medical Center, Department of Surgery, Aurora, CO, USA

Joshua I. S. Bleier, MD
University of Pennsylvania, Perelman School of Medicine, Department of Surgery, Philadelphia, PA, USA

Liliana Bordeianou, MD, MPH
Harvard Medical School, Colorectal Surgery Program at the Massachusetts General Hospital, Massachusetts General Hospital, Department of Surgery, Boston, MA, USA

Marylise Boutros, MD
Jewish General Hospital, Division of Colorectal Surgery, Montreal, QC, Canada

Mantaj S. Brar, MD, MSc GradStat
Mount Sinai Hospital, Department of Surgery, University of Toronto, Toronto, ON, Canada

W. Donald Buie, MD, MSc
Foothills Medical Center, Departments of Surgery and Oncology, University of Calgary, Calgary, AB, Canada

Jamie A. Cannon, MD
University of Alabama Birmingham Medical Center, Department of Surgery/Gastrointestinal Section, Birmingham, AL, USA

Lisa M. Cannon, MD
University of Rochester Medical Center, Department of Surgery, Division of Colon and Rectal Surgery, Rochester, NY, USA

Evie H. Carchman, MD
University of Wisconsin, Department of General Surgery, Madison, WI, USA

Joseph C. Carmichael, MD
Division of Colon and Rectal Surgery, University of California, Irvine, Department of Surgery, Orange, CA, USA

Peter A. Cataldo, MD
Larner College of Medicine at the University of Vermont, Department of Surgery, Burlington, VT, USA

Heidi Chua, MD
Mayo Clinic School of Medicine, Department of Colon and Rectal Surgery, Rochester, MN, USA

Daniel I. Chu, MD
University of Alabama at Birmingham, University Hospital, Department of General Surgery-Gastrointestinal Division, Birmingham, AL, USA

Jeffrey L. Cohen, MD, CPE
Hartford HealthCare, Hartford, CT, USA
University of Connecticut, Hartford, CT, USA

Michelle Cowan, MD
University of Washington, Department of Surgery, Seattle, WA, USA

Giovanna da Silva, MD
Cleveland Clinic Florida, Department of Colorectal Surgery, Weston, FL, USA

Jennifer S. Davids, MD
University of Massachusetts Memorial Medical Center, Department of Surgery, Worchester, MA, USA

Bradley R. Davis, MD, MBA
Department of Surgery, Atrium Health, Charlotte, NC, USA

Teresa deBeche-Adams, MD
Center for Colon & Rectal Surgery at Florida Hospital East, Orlando, FL, USA

David W. Dietz, MD
University Hospitals, Case Western Reserve University School of Medicine, Department of Surgery, Division of Colorectal Surgery, Cleveland, OH, USA

Eric J. Dozois, MD
Mayo Clinic, Division of Colon and Rectal Surgery, Rochester, MN, USA

David A. Etzioni, MD, MSHS
Mayo Clinic, Department of Surgery, Phoenix, AZ, USA

Daniel L. Feingold, MD
Division of Colorectal Surgery, Rutgers University, Department of Surgery, New Brunswick, NJ, USA

Alessandro Fichera, MD
Colon and Rectal Surgery, Baylor University Medical Center, Department of Surgery, Dallas, TX, USA

Fergal J. Fleming, MD, MPH
University of Rochester Medical Center, Department of Surgery, Rochester, NY, USA

Phillip R. Fleshner, MD
Cedars Sinai Medical Center, Department of Surgery, Los Angeles, CA, USA

Todd D. Francone, MD, MPH
Department of Surgery, Division of Colon and Rectal Surgery, Massachusetts General Hospital, Boston, MA, USA

Charles M. Friel, MD
University of Virginia Medical Center, Department of Surgery, Charlottesville, VA, USA

Wolfgang B. Gaertner, MD, MSc
Division of Colon and Rectal Surgery, University of Minnesota – M Health, Minneapolis, MN, USA

Julio Garcia-Aguilar, MD, PhD
Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA

Kelly A. Garrett, MD
Weill Cornell Medicine – New York Presbyterian Hospital, Department of General Surgery, Section of Colon and Rectal Surgery, New York, NY, USA

Susan L. Gearhart, MD, ME HP
Johns Hopkins Institutions, Department of Surgery, Baltimore, , MD, USA

Sean C. Glasgow, MD
Washington University School of Medicine, Department of Surgery, St. Louis, MO, USA

Emre Gorgun, MD
Cleveland Clinic, Department of Colorectal Surgery, Cleveland, OH, USA

Brooke H. Gurland, MD
Stanford Medical Center, Department of General Surgery, Stanford, CA, USA

Jason F. Hall, MD, MPH
Section of Colon and Rectal Surgery, Boston Medical Center, Department of Surgery, Boston, MA, USA

Karin M. Hardiman, MD, PhD
University of Alabama at Birmingham, Department of Surgery, Birmingham, AL, USA

Amanda V. Hayman, MD, MPH
Division of Gastrointestinal & Minimally Invasive Surgery, The Oregon Clinic, Portland, OR, USA

Traci L. Hedrick, MD, MSc
University of Virginia Health, Charlottesville, VA, USA

Rebecca Hoedema, MD, MS
Spectrum Health, Department of Colon and Rectal Surgery, Grand Rapids, MI, USA

Stefan David Holubar, MD, MS
Cleveland Clinic, Department of Colon and Rectal Surgery, Cleveland, OH, USA

Steven R. Hunt, MD
Washington University School of Medicine, Department of Surgery, St. Louis, MO, USA

Mehraneh D. Jafari, MD
University of California – Irvine, Department of Surgery, Orange, CA, USA

Eric K. Johnson, MD
Department of Colon and Rectal Surgery, Cleveland Clinic, Cleveland, OH, USA

William Forrest Johnston, MD
Ochsner Clinic, Department of Colon and Rectal Surgery, New Orleans, LA, USA

Matthew F. Kalady, MD
Department of Surgery, Division of Colon and Rectal Surgery, The Ohio State University, Columbus, OH, USA

Brian R. Kann, MD
Ochsner Health, Department of Colon and Rectal Surgery, New Orleans, LA, USA

Deborah S. Keller MS, , MD
University of California Davis Medical Center, Division of Colorectal Surgery, Department of Surgery, Sacramento, CA, USA

Scott R. Kelley, MD
Mayo Clinic, Division of Colon and Rectal Surgery, Rochester, MN, USA

Gregory D. Kennedy, MD, PhD
University of Alabama Medical Center, Department of Surgery, Birmingham, AL, USA

Cindy Kin, MD, MS
Stanford University, Department of Surgery, Stanford, CA, USA

Pokala Ravi Kiran, MBBS, MS (Gen Surg), MSc (EBM)
Division of Colorectal Surgery, New Presbyterian Hospital/Columbia University Medical Center, New York, NY, USA

David A. Kleiman, MD, MSc
Lahey Hospital and Medical Center, Department of Colon and Rectal Surgery, Burlington, MA, USA

Mukta K. Krane, MD
University of Washington, Department of Surgery, Seattle, WA, USA

Hiroko Kunitake, MD, MPH
Department of General and Gastrointestinal Surgery, Massachusetts General Hospital, Boston, MA, USA

Jenny Alex Ky-Miyasaka, MD, PhD
Mount Sinai Hospital, Department of Surgery, New York, NY, USA

Ron G. Landmann, MD
Section of Colon and Rectal Surgery, Baptist , MD Anderson Medical Center, Department of Surgery, Jacksonville, FL, USA

David W. Larson, MD, MBA
Mayo Clinic, Department of Surgery, Rochester, MN, USA

Amy L. Lightner, MD
Cleveland Clinic, Department of Colorectal Surgery, Cleveland, OH, USA

Anthony R. MacLean, MD
Foothills Medical Center, Department of Surgery, University of Calgary, Calgary, AB, Canada

Helen MacRaeMA, , MD
Mount Sinai Hospital, Department of Surgery, University of Toronto, Toronto, ON, Canada

Najjia N. Mahmoud, MD
Division of Colon and Rectal Surgery, University of Pennsylvania, Department of Surgery, Philadelphia, PA, USA

Nathalie Mantilla, MD
Rush University, Cook County Health, Department of Colon and Rectal Surgery, Chicago, IL, USA

Slawomir Marecik, MD
Advocate Lutheran General Hospital, Park Ridge, IL, USA
University of Illinois at Chicago, Chicago, IL, USA

David A. Margolin, MD
Ochsner Clinic Foundation, Ochsner Clinical School, University of Queensland, Department of Colon and Rectal Surgery, New Orleans, LA, USA

David J. Maron, MD, MBA
Cleveland Clinic Florida, Department of Colorectal Surgery, Weston, FL, USA

Matthew Martin, MD
Scripps Mercy Hospital, Uniformed Services University of the Health Sciences, San Diego, CA, USA

Michael F. McGee, MD
Northwestern University Feinberg School of Medicine, Department of Surgery, Division of Gastrointestinal Surgery, Chicago, IL, USA

Shane McNevin, MD
Providence Sacred Heart, Spokane, WA, USA

Anders Mellgren, MD, PhD
Division of Colon & Rectal Surgery, University of Illinois Chicago, Chicago, IL, USA

Evangelos Messaris, MD, PhD
Beth Israel Deaconess Medical Center, Harvard Medical School, Department of Surgery, Boston, MA, USA

Craig A. Messick, MD
The University of Texas , MD Anderson Cancer Center, Department Surgical Oncology, Houston, TX, USA

John Migaly, MD
Division of Surgical Oncology, Section of Colorectal Surgery, Duke University School of Medicine, Durham, NC, USA

Steven Mills, MD
Division of Colon and Rectal Surgery, University of California, Irvine, Department of Surgery, Orange, CA, USA

John R. T. Monson, MD
Digestive Health and Surgery Institute, AdventHealth, Center for Colon and Rectal Surgery, Orlando, FL, USA

Brendan John Moran, MCh, FRCS, FRCSI (Gen)
Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Department of General and Colorectal Surgery, Basingstoke, UK

Nancy Morin, MD
S, MDB Jewish General Hospital, McGill University, Department of Surgery, Division of Colorectal Surgery, Montreal, QC, Canada

Margarita Murphy, MD
East Cooper Medical Center, Department of Surgery, Mount Pleasant, SC, USA

Matthew G. Mutch, MD
Washington University School of Medicine, Department of Surgery, St. Louis, MO, USA

James W. OgilvieJr, MD, MS
Spectrum Health, Michigan State University, Department of Colorectal Surgery, Grand Rapids, MI, USA

Lucia Camara Castro Oliveira, MD, PhD
Anorectal Physiology Department and Colorectal Surgery, Hospital Casa de Saude Sao Jose and CEPEMED, Department of Colorectal Surgery, Rio de Janeiro, Brazil

Ian M. Paquette, MD
University of Cincinnati College of Medicine, Department of Surgery – Colon and Rectal Surgery, Cincinnati, OH, USA

Danielle Patterson, MD, SM
Johns Hopkins Medical Institutions, Department of Gynecology and Obstetrics, Baltimore, , MD, USA

Rodrigo Oliva Perez, MD, PhD
Angelita and Joaquim Gama Institute, Beneficencia Portuguesa de Sao Paolo, Alemao Oswaldo Cruz, Department of Surgical Oncology, Sao Paulo, Brazil

W. Brian Perry, MD
Audie L. Murphy VA Medical Center, Department of Surgery, San Antonio, TX, USA

Walter R. Peters Jr, MD, MBA
Baylor Scott and White Health, Dallas, TX, USA

Clayton C. Petro, MD
Cleveland Clinic, Department of General Surgery, Cleveland, OH, USA

Ajita Prabhu, MD
Cleveland Clinic, Department of Surgery, Cleveland, OH, USA

Jan Rakinic, MD
Southern Illinois University School of Medicine, Department of Surgery, Springfield, IL, USA

Jennifer D. Rea, MD
Colorectal Surgical and Gastroenterology Associates, Department of Colorectal Surgery, Lexington, KY, USA

Scott E. Regenbogen, MD, MPH
University of Michigan, Division of Colorectal Surgery, Department of Surgery, Ann Arbor, MI, USA

Craig A. Reickert, MD
Wayne State University, Department of Colon and Rectal Surgery, Detroit, MI, USA

Timothy J. Ridolfi, MD, MS
Medical College of Wisconsin, Division of Colorectal Surgery, Department of Surgery, Milwaukee, WI, USA

Michael J. Rosen, MD
Cleveland Clinic Center for Abdominal Core Health, Cleveland Clinic, Department of Surgery, Cleveland, OH, USA

Leslie Roth, MD
Brown University, Rhode Island Hospital, Department of Surgery, Providence, RI, USA

Ali Salim, MD
Division of Trauma, Burns, Surgical Critical Care and Acute Care Surgery, Brigham and Woman’s Hospital, Harvard Medical Schoo, Boston, MA, USA

Dana R. Sands, MD
Cleveland Clinic Florida, Department of Colorectal Surgery, Weston, FL, USA

Nicole M. Saur, MD
University of Pennsylvania, Division of Colon and Rectal Surgery, Department of Surgery, Philadelphia, PA, USA

Andrew T. Schlusse, lDO
Madigan Army Medical Center, Department of Surgery, Tacoma, WA, USA

Benjamin D. Shogan, MD
University of Chicago, Department of Surgery, Chicago, IL, USA

Radhika K. Smith, MD
Washington University in St. Louis, Department of Surgery, St. Louis, MO, USA

Michael J. Snyder, MD
McGovern School of Medicine, Department of Surgery, Houston, TX, USA

Michael J. Solomon, MB BCH (Hons), BAO, MSc DMEDSC
Royal Prince Alfred Hospital, Department of Colorectal Surgery, Sydney, NSW, Australia

Antonino Spinelli, MD, PhD
Department of Biomedical Sciences, Humanitas University, Milan, Italy
IRCCS Humanitas Research Hospital - Division of Colon and Rectal Surgery, Milan, Italy

Kyle Staller, MD, MPH
Division of Gastroenterology, Massachusetts General Hospital, Boston, MA, USA

Emily Steinhagen, MD
University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Surgery, Cleveland, OH, USA

David B. Stewart, MD
Southern Illinois University School of Medicine, Department of Surgery, Springfield, IL, USA

Luca Stocchi, MD
Mayo Clinic Florida, Department of Surgery, Division of Colorectal Surgery, Jacksonville, FL, USA

Scott A. Strong, MD
Northwestern University, Department of Surgery, Chicago, IL, USA

Pasithorn A. Suwanabol, MD, MS
University of Michigan, Division of Colorectal Surgery, Department of Surgery, Ann Arbor, MI, USA

Patricia Sylla, MD
Department of Surgery, Division of Colon and Rectal Surgery, Icahn School of Medicine at Mount Sinai, Mount Sinai Hospital, New York, NY, USA

Sanda A. Tan, MD, PhD
West Florida Healthcare, Department of Surgery, University of Central Florida, Pensacola, FL, USA

Erin A. Teeple, MD
Nemours/AI Dupont Hospital for Children, Department of Surgery, Wilmington, DE, USA

Julie Thacker, MD
Department of Surgery, Duke University School of Medicine, Durham, NC, USA

Amy J. Thorsen, MD
Colon and Rectal Surgery Associates, Minneapolis, MN, USA

V. Liana Tsikitis, MD, MBA, MCR
Oregon Health and Science University, Department of General Surgery, Division of Gastroenterology, Portland, OR, USA

Konstantin Umanskiy, MD
University of Chicago, Department of Surgery, Chicago, IL, USA

Michael A. Valente DO
Cleveland Clinic, Department of Colorectal Surgery, Cleveland, OH, USA

H. David Vargas, MD
Ochsner Clinic Foundation, Department of Colon and Rectal Surgery, New Orleans, LA, USA

Carol-Ann Vasilevsky, MD
Jewish General Hospital, Department of Surgery, Montreal, QC, Canada

Jon D. Vogel, MD
University of Colorado, Aurora, CO, USA

Sarah A. Vogler, MD, MBA
Cleveland Clinic, Department of Colorectal Surgery, Cleveland, OH, USA

Eric G. Weiss, MD
Cleveland Clinic Florida, Department of Colorectal Surgery, Weston, FL, USA

Mark H. Whiteford, MD
Colon and Rectal Surgery, The Oregon Clinic, Providence Portland Medical Center, Providence Cancer Institute, Gastrointestinal and Minimally Invasive Surgery Division, Portland, OR, USA

Elizabeth C. Wick, MD
University of California, San Francisco, Department of Surgery, San Francisco, CA, USA

Kirsten Bass Wilkins, MD
Associated Colon and Rectal Surgeons, PA, Edison, NJ, USA

Dennis Yang, MD
University of Florida, Department of Gastroenterology, Gainesville, FL, USA

Karen N. Zaghiyan, MD
Cedars Sinai Medical Center, Department of Surgery, Los Angeles, CA, USA

Matthew D. Zelhart, MD
Department of Surgery, Tulane University School of Medicine, New Orleans, LA, USA

Massarat Zutshi, MD
Cleveland Clinic, Department of Colorectal Surgery, Digestive Disease and Surgery Institute, Cleveland, OH, USA

Preface

The ASCRS Textbook of Colon and Rectal Surgery has long served as a cornerstone of education and clinical reference in our specialty. Today, it has evolved into something more than a textbook—it is a living resource, continuously updated and refined to reflect the ever-changing landscape of colorectal surgery.

Now published as part of ASCRS U, the ASCRS dynamic online educational platform, this textbook benefits from the collective expertise and dedication of ASCRS members. Through their ongoing contributions, the textbook authors and editors regularly revise the content to incorporate the latest literature, innovations in technique, and shifts in clinical practice. This format ensures that learners and practitioners have access to the most current, evidence-based guidance—delivered in real time and tailored to the needs of a modern surgical community.

Colorectal surgery is a field defined by progress. From advances in minimally invasive approaches and enhanced recovery protocols to the integration of precision medicine and global health perspectives, our specialty continues to evolve at a remarkable pace. This living textbook reflects that momentum, offering not only foundational knowledge but also a forward-looking view of where we are headed.

We are deeply grateful to the surgeons, educators, and researchers whose hard work and insight make this resource possible. Their commitment to excellence and education ensures that this textbook remains a trusted, relevant, and inspiring tool for all who seek to improve the care of patients with colorectal disease. We thank them for writing and revising, when needed, the chapters in this textbook.

Finally, we would like to thank Elizabeth Moran, the ASCRS Editorial Manager, for her extraordinary efforts and thoroughness in overseeing and ensuring the timely completion of the textbook.

We are deeply indebted to our teachers and mentors, who have been our heroes and generously shared their knowledge, experience, and enthusiasm over the years. We devote this edition to our trainees, whose energy, intellectual curiosity, and commitment to excellence drive us every day to be better. Pass it forward!

– The Editors
American Society of Colon and Rectal Surgeons

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