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Andrew T. Chan, MD, MPH

Program Director, Gastroenterology Training Program

  • Phone: 617-726-3212
Department of Medicine


  • Cancer Center
  • Cancer Risk Assessment
  • Digestive Healthcare Center
  • Colorectal Center
Clinical Interests
Cancer prevention
Colon and rectal cancer
Hereditary colorectal cancer
Gastrointestinal cancer
Boston: Massachusetts General Hospital
Medical Education
MD, Harvard Medical School
M.P.H., Harvard School of Public Health
Residency, Massachusetts General Hospital
Fellowship, Massachusetts General Hospital
Board Certifications
Gastroenterology, American Board of Internal Medicine
Patient Age Group
Accepting New Patients
Accepting New Patients


View my most recent publications at PubMed

  1. Nishihara R, Wu K, Lochhead P, Morikawa T, Liao X, Qian ZR, Inamura K, Kim SA, Kuchiba A, Yamauchi M, Imamura Y, Willett WC, Rosner BR, Fuchs CS, Giovannucci E, Ogino S , Chan AT (co-senior authors). Long-term colorectal-cancer incidence and mortality after lower endoscopy. N Engl J Med 2013. 369(12):1095-105.
  2. Nishihara R, Lochhead P, Kuchiba A, Jung S, Yamauchi M, Liao X, Imamura Y, Qian ZR, Morikawa T, Wang M, Spiegelman D, Cho E, Giovannucci E, Fuchs CS, Chan AT , Ogino S (co-senior authors). Aspirin use and risk of colorectal cancer according to BRAF mutation status. JAMA. 2013. 309: 2563-71. PMCID: PMC3743040
  3. Liao X, Lochhead P, Nishihara R, Morikawa T, Kuchiba A, Yamauchi M, Imamura Y, Qian Z, Baba Y, Shima K, Meyerhardt JA, Giovannucci E, Fuchs CS, Chan AT , Ogino S (co-senior authors). Aspirin use, PIK3CA mutation, and colorectal cancer survival. N Engl J Med. 2012; 367: 1596-606. PMCID: PMC3532946
  4. Chan AT, Ogino S, Giovannucci EL, Fuchs CS. Inflammatory markers are associated with risk of colorectal cancer and chemopreventative response to anti-inflammatory drugs. Gastroenterology. 2011. 140(3): 799-808. PMCID: PMC3049858
  5. Chan AT, Ogino S, Fuchs CS. Aspirin use and survival after diagnosis of colorectal cancer. JAMA. 2009;302(6):649-58. PMCID: PMC2848289. Chan AT, Ogino S, Fuchs CS. Aspirin and the risk of colorectal cancer in relation to the expression of COX-2. N Engl J Med. 2007;356(21):2131-42.

Study reveals aspirin's colorectal cancer prevention mechanism

Aspirin therapy's ability to reduce the risk of colorectal cancer, an association seen in a large number of studies, appears to depend on the drug's inhibition of the COX-2 enzyme, the action that also underlies aspirin's usefulness for treating pain and inflammation.

Workshop on Metagenomics

The Harvard University Center for AIDS Research, in collaboration with the Ragon Institute of MGH, MIT and Harvard, and the Clinical and Translational Epidemiology Unit at MGH, is sponsoring a week-long workshop focused exclusively on computational approaches to metagenomic analysis.

Postdiagnosis aspirin use reduces risk of dying from colorectal cancer

Regular use of aspirin after colorectal cancer diagnosis may reduce the risk of cancer death, report investigators from Massachusetts General Hospital, Dana-Farber Cancer Institute and Brigham and Women’s Hospital.

Aspirin's ability to protect against colorectal cancer may depend on risk-associated inflammatory pathways

The reduced risk of colorectal cancer associated with taking aspirin or other nonsteroidal anti-inflammatory drugs may be limited to individuals already at risk because of elevations in a specific inflammatory factor in the blood.

Study shows colonoscopy better than sigmoidoscopy in protecting against colorectal cancer

A new study finds that colonoscopy appears to reduce the risk of developing or dying from colorectal cancer more powerfully than does sigmoidoscopy, a similar procedure that examines only a portion of the colon. The investigation also identifies molecular features that may help explain tumors that are diagnosed despite an individual's having recently undergone colonoscopy.

Study Shows Aspirin Can Reduce Colorectal Cancer Risks for Those with Specific Gene

Researchers from MGH, Dana-Farber Cancer Institute and Case Western Reserve School of Medicine have shown that aspirin’s previous reported ability to reduce the risk of colorectal cancer applies only to individuals with high levels of a specific gene product in their colons.

Gastroenterology Associates
55 Fruit Street
Boston, MA 02114-2696

Phone: 617-726-3212
Fax: 617-724-6832

Gastroenterology Associates
55 Fruit Street
Boston, MA 02114-2696

Phone: 617-726-3212
Fax: 617-724-6832

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