Our Gastrointestinal Cancer Team

The activities of our gastrointestinal cancer specialists are integrated through a multispecialty clinic, where you will be seen regularly and clinicians will regularly review your progress. Our staff includes expert medical oncologists, surgeons, gastroenterologists, radiologists, radiation oncologists, nurses, social workers and nutritionists.

Medical Oncology


Andrea Bullock, MD

Andrea J. Bullock, MD, MPH

Disease Group Leader, Gastrointestinal Malignancies; Medical Oncology

Ali Baghian, MD

Ali Baghian, MD

Medical Oncology


Bruno Bockorny, MD

Medical Oncology


Mary Linton Peters, MD

Medical Oncology

Ahmed Rattani, MD

Ahmed Rattani, MD

Instructor, Medicine, Harvard Medical School

Peter Whooley, DO

Peter D. Whooley, DO, MBA

Medical Oncology

Jessica Zerillo

Jessica A. Zerillo, MD, MPH

Medical Oncology

Learn more about Dr. O'Rourke

Jenna O’Rourke, NP

Learn more about Caroline Trickett

Caroline Trickett, NP

Nurse Coordinators
Learn more about Luiz Duque, RN

Luiz Duque, RN

Arielle Lasoff

Arielle Lasoff, RN

Learn more about Nicole Reilly, RN

Nicole Reilly, RN

Interventional Gastroenterology

Tyler Berzin, MD, MS

Director, Advanced Endoscopy Fellowship Program; Gastroenterology

Moamen M. Gabr, MD

Moamen M. Gabr, MD

Director, Endoluminal Surgery; Gastroenterology

Douglas Pleskow, MD

Clinical Chief, Gastroenterology

Mandeep S. Sawhney, MD

Director, Therapeutic Endoscopy; Endoscopy Research; Gastroenterology

Radiation Oncology

Matthew Abrams, MD

Radiation Oncology

Raechel Perry

Raechel Perry, NP

Radiation Oncology


Muneeb Ahmed, MD

Muneeb Ahmed, MD, FSIR

Chief, Vascular & Interventional Radiology; Vice Chair of Interventional Services; Diagnostic Radiology

Diana Dinh, MD

Diana Dinh, MD

Vascular & Interventional Radiology; Diagnostic Radiology; Liver Tumor Clinic

Robert A. Kane, MD

Abdominal Radiology

Gerald Kolodny, MD

Nuclear Medicine; Diagnostic Radiology

Karen S. Lee, MD

Director, Radiology Fellowship Training Programs; Diagnostic Radiology

J. Anthony Parker, MD, PhD

Nuclear Medicine

Bettina Siewert, MD

Executive Vice Chair, Radiology; Diagnostic Radiology

Martin P. Smith, MD

Director of Community MRI; Interventional Radiology; Diagnostic Radiology

Jesse L. Wei, MD

Clinical Director of CT; Neuroradiology; Interventional Radiology; Diagnostic Radiology

Surgical Oncology

Umut Sarpel, MD, MSc, FACS, FSSO

Umut Sarpel, MD, MSc, FACS, FSSO

Chief, Division of Surgical Oncology

Colon and Rectal
Thomas Cataldo

Thomas E. Cataldo, MD

Colon & Rectal Surgery; Surgery

Kristen T. Crowell, MD

Kristen T. Crowell, MD

Colon & Rectal Surgery

Evangelos Messaris, MD, PhD, FACS, FASCRS

Chief, Colon and Rectal Surgery; Colon & Rectal Surgery; Surgery

Daniel Wong, MD

Daniel Wong, MD

Colon & Rectal Surgery


Vanessa L. Cowan, MD


Learn more about Dr. Dib Marambio

Martin J. Dib Marambio, MD

Director, Hepatobiliary Surgery, Director, Living Donor Liver Transplant Program

Amy Evenson

Amy R. Evenson, MD, MPH, FACS

Surgical Director of Kidney & Pancreas Transplant


Nurse Practitioner
Learn more about Jeanne Quinn

Jeanne Quinn, MS, APRN-BC

Rectal Cancer Program Coordinator

Nurse Navigator
Learn more about Mary Keane

Mary Keane, RN


Vikram Deshpande, MD

Vikram Deshpande, MD

Director of GI Pathology; Director of Bone and Soft Tissue Pathology

Gamze Ayata, MD

Gamze Ayata, MD

Director of Gastrointestinal and Liver Pathology Fellowship

Kanchan Kantekure, MD


Learn more about Dr. Nasser

Imad A. Nasser, MD

Director of Hepatobiliary Pathology

Matthew Rosenbaum, MD

Matthew Rosenbaum, MD


Helen Wang, MD

Helen H. Wang, MD, MPH, DrPH

Osman Yilmaz, MD - Photo Unavailable

Osman Yilmaz, MD



Learn more about Logan J. Ruff

Logan J. Ruff

Program Coordinator

Learn more about Teneisha Powell

Teneisha Powell

Administrative Assistant

Learn more about Elizabeth Tyra

Elizabeth Tyra

Administrative Assistant

Sarah Cowen

Sarah Cowen

Administrative Assistant