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Mark H. O'Hara, MD

Mark H. O'Hara, MD Physician

Assistant Professor of Medicine at the Hospital of the University of Pennsylvania

Dr. O'Hara is employed by Penn Medicine.

Patient Satisfaction Ratings

Patient Rating Breakdown

The Patient Satisfaction Rating is an average of all responses to the care provider related questions shown below from our nationally-recognized Press Ganey Patient Satisfaction Survey. Patients that are treated in outpatient or hospital environments may receive different surveys, and the volume of responses will vary by question.

Responses are measured on a scale of 1 to 5 with 5 being the best score.

Comments are submitted by patients and reflect their views and opinions. The comments are not endorsed by and do not necessarily reflect the views of Penn Medicine.

Overall Ratings

Clinical Specialties


  • Hematology
  • Medical Oncology

Programs & Centers:

Board Certification:

  • Internal Medicine, 2011

Clinical Expertise:

  • Ampullary Cancer
  • Bile Duct Cancer (Cholangiocarcinoma)
  • Colon Cancer
  • Esophageal Cancer
  • Gastrointestinal Stromal Tumors (GIST)
  • Gastrointestinal Tumor
  • Hepatocellular Carcinoma (HCC)
  • Liver Cancer
  • Liver Metastases (Secondary Liver Cancer)
  • Neuroendocrine Tumors
  • Pancreatic Cancer
  • Pancreatic Neuroendocrine Tumors (Islet Cell Tumors)
  • Rectal Cancer
  • Stomach Cancer (Gastric Cancer)

Description of Clinical Expertise

GI cancers, Phase 1 trials, Pancreatic cancer, Colorectal cancer, Anal cancer, Esophageal cancer, Gastric cancer, Hepatocellular carcinoma, Cholangiocarcinoma, Neuroendocrine tumor

Practice Locations and Appointments

Insurance Accepted

  • Aetna US Healthcare
  • Amerihealth Caritas
  • Amerihealth Caritas Medicare
  • Cigna
  • Cigna HealthSpring
  • Clover Health Plan
  • CVS Health
  • Devon Health Services (Americare)
  • Gateway Health Plan
  • Geisinger Health Plan
  • HealthAmerica / HealthAssurance, a Coventry Plan
  • HealthPartners
  • HealthPartners Medicare
  • HealthSmart
  • Highmark Blue Shield
  • Horizon Blue Cross Blue Shield of New Jersey
  • Humana / Choicecare
  • Independence Blue Cross (Keystone East)
  • Intergroup
  • Keystone First
  • Keystone First Medicare
  • Multiplan
  • NJ Medicaid
  • NJ Qualcare
  • Oxford Health Plan
  • PA Medicaid
  • PA Medicare
  • Preferred Health Care/LGH
  • Rail Road Medicare / Palmetto GBA
  • Remedy Partners at Penn Medicine
  • Tricare
  • United Healthcare
  • UnitedHealthcare Community Plan
  • US Family Health Plan
  • Vetrans Choice Program (6/2018 Not Active)

Education and Training

Medical School: State University of New York at Stony Brook
Residency: University of Pittsburgh Medical Center
Fellowship: Hospital of the University of Pennsylvania


American Association for Cancer Research, National American College of Physicians, National American Society of Clinical Oncology, National American Society of Hematology, National Eastern Cooperative Oncology Group, National Parker Center for Cancer Immunotherapy, National

Hospital Affiliation

Dr. O'Hara is employed by Penn Medicine.

Hospital Privileges:

  • Hospital of the University of Pennsylvania: Has privileges to treat patients in the hospital.


Description of Research Expertise:

Pancreatic cancer, colorectal cancer, GI cancers, Phase 1, CAR T cell therapy

Selected Publications:

Shabason JE, Chen J, Apisarnthanarax S, Damjanov N, Giantonio B, Loaiza-Bonilla A, O'Dwyer PJ, O'Hara M, Reiss KA, Teitelbaum U, Wissel P, Drebin JA, Vollmer C, Kochman M, Mick R, Vergara N, Jhala N, Doucette A, Lukens JN, Plastaras JP, Metz JM, Ben-Josef E.: A phase I dose escalation trial of nab-paclitaxel and fixed dose radiation in patients with unresectable or borderline resectable pancreatic cancer. Cancer Chemother Pharmacol. : 2018.

Phase II trial of palbociclib in patients with advanced esophageal or gastric cancer.: Karasic TB, O’Hara MH, Teitelbaum UR, Damjanov N, Giantonio BJ, d’Entremont TS, Gallagher M, Zhang PJ, O’Dwyer PJ. J Clin Oncol, (4S_suppl), 68 36 : 2018.

A single arm phase II study of rucapariob maintenance in patients with advanced pancreatic adenocarcinoma and a known deleterious BRCA1, BRCA2 or PALB2 mutation who have achieved stability on platinum therapy.: Reiss KA, Maxwell KN, Nathanson K, Teitelbaum UR, O’Hara MH, O’Dwyer PJ, Schneider C, Carpenter EL, Mick R, Domcheck SM. J Clin Oncol 36(4S_suppl), TPS531 : 2018.

Reiss KA, Ben-Josef E, Damjanov N, Hoteit M, O’Hara MH, Karasic TB, Teitelbaum UR, Schneider C, O’Dwyer PJ, Carpenter EL, Mick R, Vonderheide RH.: A pilot study of galunisertib (LY2157299) plus stereotactic body radiotherapy (SBRT) in advanced hepatocellular carcinoma (HCC). J Clin Oncol 36(4S_suppl), TPS528 : 2018.

Ko J, Bhagwat N, Yee SS, Ortiz N, Sahmoud A, Black T, Aiello NM, McKenzie L, O’Hara M, Redlinger C, Romeo J Carpenter EL, Stanger BZ, Issadore D: Combining machine learning and nanofluidic technology to diagnose pancreatic cancer using exosomes ACS Nano 11 (11): 11182-11193,2017.

O’Hara MH, Mick R, Lyman J, Xu J, Hosseini M, LaVallee T, Gherardini PF, Vance B, Trifan O, Dugan U, Shalabi A, Ibrahima R, Vonderheide RH.: A phase Ib/2 study of CD40 agonistic monoclonal antibody (APX005M) together with gemcitabine and nab-paclitaxel with or without nivolumab in untreated metastatic pancreatic adenocarcinoma patients. Society for Immunotherapy of Cancer (SITC), National Harbor, MD : 2017.

Ko J, Bhagwat N, Yee SS, Black T, Redlinger C, Romeo J, O’Hara M, Raj A, Carpenter EL, Stanger BZ, Issadore D: A magenetic micropore chip for rapid (<1 hour) unbiased circulating tumor cell isolation and in situ RNA analysis Lab Chip 17 (18): 3086-3096,2017.

O’Hara MH, Stashwick C, Plesa G, Tanyi JL: Overcoming barriers of CAR T cell therapy in patients with mesothelin-expressing cancers Immunotherapy 9 (9): 767-780,2017.

O'Hara MH, Loaiza-Bonilla A, Redlinger M, Damjanov N, Teitelbaum UR, Vasilevskaya I, Rosen MA, Heitjan DF, Amaravadi RK, O'Dwyer PJ: Phase II trial of autophagy inhibition using hydroxychloroquine (HCQ) with FOLFOX/bevacizumab in the first-line treatment of advanced colorectal cancer. American Society of Clinical Oncology Annual Conference, Chicago, IL : 2017.

Flynn JP, O’Hara MH, Gandhi SJ.: Preclinical rationale for combining radiation therapy and immunotherapy beyond checkpoint inhibitors (i.e. CART). Translational Lung Cancer Research 6 (2): 159-168,2017.

Academic Contact Info

Division of Hematology Oncology
Perelman Center for Advanced Medicine
10th Floor, South Pavilion
Office #10-306
3400 Civic Center Blvd

Philadelphia, PA 19104
Phone: (215) 360-0735
Patient appointments: 800-789-7366 (PENN)