Internationally Recognized Leaders in Colorectal Surgical Care

Two generations of colorectal surgical care, research, technical innovation, and professional leadership.

Meet the Team

  • Dr. John Marks at Lankenau Medical Center's Annenberg Center

    John H Marks, MD, FACS, FASCRS

    DIRECTOR

    Dr. Marks is board certified in both General Surgery and Colorectal Surgery. He has performed over 2000 laparoscopic colorectal operations and has the largest colorectal single-port robot operative experience in the United States. Building on a commitment to preserving function in patients with rectal cancer through a program of integrated care to preserve the anal sphincter, his academic and professional signature is achieving proven superior outcomes in the least invasive ways possible.

  • Henry Schoonyoung, MD, FACS, FASCRS

    ASSOCIATE

    Dr. Schoonyoung is board certified in both General Surgery and Colorectal Surgery and a graduate of the Lankenau general surgery residency. After completing a colorectal surgery residency and broadening his teaching and practice experience in other healthcare systems, he seized the opportunity in 2015 to join Dr. Marks and return to Main Line Health. More recently, he is the recipient of teaching awards, recognized regionally as a Top Doc, and is the principal investigator in a clinical trial of a novel, portable, single-port robot.

Call +1 610.645.9093 or click the button to schedule an appointment

Our Clinical Fellow and Research Team Members

  • Brandon Vu, MD

    CLINICAL FELLOW

  • Avihai Moscovici, MD

    RESEARCH FELLOW II

  • Emma Ton

    Emma Ton, B.S.

    RESEARCH ASSISTANT

  • Tyler Bogaczyk, MD

    RESEARCH FELLOW II

Our Services

Our Facility

The Colorectal Center at Lankenau Medical Center

A state-of-the-art center designed to enable the integration of clinical excellence, technical innovation, and research in every patient visit.

Our Inpatient Team

Our ability to do amazing work for patients depends on cohesive teams in the office, operating room, and inpatient ward at the Lankenau Medical Center Colorectal Unit

Lankenau Medical Center Colorectal Inpatient Unit Team with Dr. John Marks

Marks Colorectal Surgical Research Foundation

Learn more about the research foundation and how you can help.