About Me

I am a gastroenterologist with an interest in hereditary colon cancer syndromes — specifically Lynch Syndrome (LS) or Hereditary Nonpolyposis Colorectal Cancer (HNPCC) — as well as in specialized nutrition support for cancer patients. After graduating from Georgetown University School of Medicine, I completed an internship and residency in internal medicine at NewYork-Presbyterian Hospital/Weill Cornell Medical Center, followed by a year of chief residency at New York Downtown Hospital and specialty training in gastroenterology and nutrition at Memorial Sloan Kettering Cancer Center.

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I perform gastrointestinal endoscopic procedures including colonoscopy, upper gastrointestinal endoscopy, small intestinal enteroscopy, and percutaneous endoscopic gastrostomies. In addition, I am trained in more-advanced endoscopic techniques, including direct percutaneous endoscopic jejunostomies, endoscopic retrograde cholangiopancreatography (ERCP), and placement of stents. I am also board certified in nutrition and provide enteral and total parenteral nutrition (TPN) to patients requiring nutrition support.

My on-going research focuses on high-risk colon cancer patients, specifically on patients with LS and their families. Though we have made great strides in understanding LS, these patients continue to suffer from significant morbidity and mortality from colorectal and other associated cancers. My research involves looking at the role that screening and nutrition can play in the prevention of cancer in these high-risk patients.

  • Clinical Expertise: Hereditary Colon Cancer Syndromes (Lynch Syndrome, Hereditary Nonpolyposis Colorectal Cancer), Nutrition Support. Colonosopy, Upper Gastrointestinal Endoscopy; Percutaneous Endoscopic Gastrostomies and Jejunostomies; Endoscopic Retrograde Cholangiopancreatography (ERCP); Placement of Bnteral and biliary Stents.
  • Languages Spoken: English
  • Education: MD, Georgetown University School of Medicine
  • Residencies: NewYork-Presbyterian Hospital/Weill Cornell Medical Center
  • Fellowships: Memorial Sloan Kettering Cancer Center
  • Board Certifications: Internal Medicine; Nutrition

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Mendelsohn RB, Gerdes H, Markowitz AJ, DiMaio CH, Schattner MA. Carcinomatosis is not a contraindication to enteral stenting in select patients with malignant gastric outlet obstruction.. Gastrointestinal Endoscopy 2011 Jun; 73(6):1125-40

Mendelsohn RB, DiMaio CJ. Do all patients with esophageal cancer require surgery or can some be managed with nonsurgical (endoscopic, oncologic, etc) methods alone? In Curbside Consultation in GI Cancer for the Gastroenterologist: 49 clinical questions, edited by D. Adler, New Jersey: Slack Incorporated; 2011: 7-12.

Mendelsohn R, Markowitz A, Gerdes H. Polipopses. In: Averbach M, Correa P, eds. Colonoscopia. Sao Paulo: Santos, 2010: 157-175

Clinical Trials

As home to one of the world’s top cancer research centers, Memorial Sloan Kettering is typically involved in more than 900 clinical trials at a given time. Currently, clinical trials focused on the conditions I treat are enrolling new patients. If you’re interested in joining a clinical trial, click to learn about the trial’s purpose, eligibility criteria, and how to get more information.

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Most major health insurers offer plans that include MSK as one of their in-network providers. If MSK is in-network, it means all our doctors are too. Medicaid and New York State Medicare also provide benefits for care at MSK.

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