Jason A. Castellanos, MD, MS

Clinical Locations

Primary Location

Fox Chase Cancer Center
333 Cottman Avenue
Philadelphia, PA 19111


Assistant Professor, Department of Surgical Oncology

Treatment Focus

Cancers of the liver, gall bladder, bile ducts, and pancreas; Colorectal liver metastases; Hepatic atery infusion pump chemotherapy; Robotic surgery; Minimally invasive surgery

Treatment Philosophy

I’m honored to be part of the talented team at Fox Chase Cancer Center. As a surgeon with specialty training in both Surgical Oncology and Hepato-Pancreato-Biliary surgery, I am focused on caring for people with benign, pre-cancerous, and malignant (cancerous) diseases of the liver, gallbladder, bile ducts, and pancreas, as well as cancers that have spread to the liver from the colon.

I completed medical school and general surgery residency at Vanderbilt University Medical Center in Nashville, Tennessee. During residency I completed a two-year research fellowship studying therapeutic resistance in pancreatic cancer, and I spent an additional two years completing a MS in Biomedical Informatics. The skills I gained during these research fellowships have been useful in almost every task I encounter, whether they are administrative, clinical, or research oriented.

My clinical training in Surgical Oncology was completed at Memorial Sloan Kettering Cancer Center. In addition to training in the full breadth of surgical oncology, I spent my final year of training specifically focused on diseases of the liver, gallbladder, bile ducts, and pancreas. This involved extensive training in robotic and laparoscopic approaches to remove tumors of the liver and pancreas, placement of hepatic artery infusion chemotherapy pumps for the treatment of colorectal liver metastases and intrahepatic cholangiocarcinoma, and the use of heat (ablation) and electricity (irreversible electroporation) to treat colorectal liver metastases.

The most formative training I received, however, has been helping family members through cancer treatment. My priority is to help you and your family members through each stage of treatment with the same level of diligence, compassion and honesty that I would give to my own family. I chose to practice at Fox Chase not only because it is a storied institution with dedicated specialists providing the highest quality of care, but also because of the profound sense of camaraderie, team work, and institutional pride evident in every interaction here.

Education and Training

Educational Background

  • Fellow in Hepatopancreaticobiliary Surgery, Memorial Sloan Kettering Cancer Center, New York, NY - 2019-2020
  • Fellow in Complex General Surgical Oncology, Memorial Sloan Kettering Cancer Center, New York, NY - 2018-2020
  • Master of Science - Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN - 2014-2016
  • Categorical Resident in General Surgery, Vanderbilt University School of Medicine, Nashville, TN - 2009-2018
  • Doctor of Medicine, Vanderbilt University School of Medicine, Nashville, TN - 2005-2009
  • Bachelor of Arts - Sociology, Stanford University, Stanford, CA - 2002-2004
  • United States Military Academy, West Point, NY - 2000-2002


  • American Board of Surgery, Certified in General Surgery
    • Certificate #064885 (Exp. 06/04/2029)
  • American Board of Preventive Medicine, Board certified in Clinical Informatics
  • New York State Physician License #291607-1
    • Certificate #9952793UPD (Exp. 5/31/2021)


  • American College of Surgeons, 2009-Present
  • Association for Academic Surgery, 2011-Present
  • American Pancreatic Association, 2012-Present
  • Pancreas Club, 2013-2016
  • American Association of Cancer Research, 2014-Present
  • American Medical Informatics Association
  • Society of Surgical Oncology, 2015-Present

Honors & Awards

  • 2017 - Administrative Chief Resident, General Surgery Residency, Vanderbilt University Medical Center – Department of Surgery
  • 2016 - Academic Surgical Congress Research Award, Society of Asian Academic Surgeons
  • 2016 - Outstanding Resident Research Award, Basic Science, Association of Academic Surgeons
  • 2013 - Kenneth Warren Research Award, Pancreas Club
  • 2012 - Best Resident Cancer Paper, Tennessee Chapter of the American College of Surgeons
  • 2009 - Levi Watkins Jr. Student Award for Commitment to Diversity, Vanderbilt University School of Medicine
  • 2009 - H. William Scott Society Prize in Surgery, Vanderbilt University School of Medicine
  • 2009 - Alpha Omega Alpha
Research Profile
  • 2012-2014 - STAT3 signaling in pancreatic cancer and the tumor microenvironment (Advisor: Nipun Merchant, MD)
  • 2014-2016 - Prediction of colorectal cancer recurrence through integration of multiple views of genomic and clinical data (Advisor: Bing Zhang, PhD)

Selected Publications

Dosch, Austin R., Xizi Dai, Alexander A. Gaidarski Iii, Chanjuan Shi, Jason A. Castellanos, Michael N. VanSaun, Nipun B. Merchant, and Nagaraj S. Nagathihalli. “Src Kinase Inhibition Restores E-Cadherin Expression in Dasatinib-Sensitive Pancreatic Cancer Cells.” Oncotarget 10, no. 10 (February 1, 2019): 1056–69. PMID: 30800218.

Totiger, Tulasigeri M., Supriya Srinivasan, Venkatakrishna R. Jala, Purushottam Lamichhane, Austin R. Dosch, Alexander A. Gaidarski, Chandrashekhar Joshi, Shobith Rangappa, Jason A. Castellanos, Praveen Vemula, Xi Chen, Deukwoo Kwon, Nilesh Kashikar, Michael VanSaun, Nipun Merchant, and Nagaraj Nagathihalli. “Urolithin A, a Novel Natural Compound to Target PI3K/AKT/MTOR Pathway in Pancreatic Cancer.” Molecular Cancer Therapeutics 18, no. 2 (February 1, 2019): 301–11. PMID: 30404927.

Srinivasan, Supriya, Tulasigeri Totiger, Chanjuan Shi, Jason A. Castellanos, Purushottam Lamichhane, Austin R. Dosch, Fanuel Messaggio, et al. “Tobacco Carcinogen-Induced Production of GM-CSF Activates CREB to Promote Pancreatic Cancer.” Cancer Research 78, no. 21 (November 1, 2018): 6146–58. PMID: 30232221.

Nagathihalli, Nagaraj S., Jason A. Castellanos, Purushottam Lamichhane, Fanuel Messaggio, Chanjuan Shi, Xizi Dai, Priyamvada Rai, Xi Chen, Michael N. VanSaun, and Nipun B. Merchant. “Inverse Correlation of STAT3 and MEK Signaling Mediates Resistance to RAS Pathway Inhibition in Pancreatic Cancer.” Cancer Research 78, no. 21 (November 1, 2018): 6235–46. PMID: 30154150.

Messaggio, Fanuel, Alisha M. Mendonsa, Jason A. Castellanos, Nagaraj S. Nagathihalli, Lee Gorden, Nipun B. Merchant, and Michael N. VanSaun. “Adiponectin Receptor Agonists Inhibit Leptin Induced PSTAT3 and in Vivo Pancreatic Tumor Growth.” Oncotarget 8, no. 49 (October 17, 2017): 85378–91. PMID: 29156726.

Kummerow Broman, Kristy, Christianne L. Roumie, Melissa K. Stewart, Jason A. Castellanos, John L. Tarpley, Robert S. Dittus, and Richard A. Pierce. “Implementation of a Telephone Postoperative Clinic in an Integrated Health System.” Journal of the American College of Surgeons 223, no. 4 (2016): 644–51. PMID: 2754510.

Nagathihalli, Nagaraj S., Jason A. Castellanos, Michael N. VanSaun, Xizi Dai, Mahogany Ambrose, Qiaozhi Guo, Yanhua Xiong, and Nipun B. Merchant. “Pancreatic Stellate Cell Secreted IL-6 Stimulates STAT3 Dependent Invasiveness of Pancreatic Intraepithelial Neoplasia and Cancer Cells.” Oncotarget 7, no. 40 (October 4, 2016): 65982–92. PMID: 27602757.

Walsh, Alex J., Jason A. Castellanos, Nagaraj S. Nagathihalli, Nipun B. Merchant, and Melissa C. Skala. “Optical Imaging of Drug-Induced Metabolism Changes in Murine and Human Pancreatic Cancer Organoids Reveals Heterogeneous Drug Response.” Pancreas 45, no. 6 (2016): 863–69. PMID: 26495796.

Nagathihalli, Nagaraj S.*, Jason A. Castellanos*, Chanjuan Shi, Yugandhar Beesetty, Michelle L. Reyzer, Richard Caprioli, Xi Chen, et al. “Signal Transducer and Activator of Transcription 3, Mediated Remodeling of the Tumor Microenvironment Results in Enhanced Tumor Drug Delivery in a Mouse Model of Pancreatic Cancer.” Gastroenterology 149, no. 7 (December 2015): 1932-1943.e9. PMID: 26255562. *Co-first authors.

Guo Q, Ambrose M, Yugandhar Beesetty, Jason A. Castellanos, Nagaraj Nagathihalli, Nipun Merchant. IL-6 secreted from pancreatic stellate cells activates STAT3 and promotes cell growth and invasive ability of pancreatic cancer. Young Scientist. 2014; 4:63-65.

Castellanos, Jason A., and Nipun B. Merchant. “Intensity of Follow-up after Pancreatic Cancer Resection.” Annals of Surgical Oncology 21, no. 3 (March 2014): 747–51. PMID: 24092447.

Castellanos, Jason A., Christina M. Edwards, Aaron Shaver, Nipun B. Merchant, and Alexander A. Parikh. “Appendiceal Adenocarcinoma Presenting as Venous Thromboembolism: An Unusual Presentation of a Rare Carcinoma.” The American Surgeon 76, no. 5 (May 2010): 543–44. PMID: 20506889.

Merchant, Nipun B., Jennifer Rymer, Elizabeth A. S. Koehler, G. Daniel Ayers, Jason A. Castellanos, David A. Kooby, Sharon H. Weber, et al. “Adjuvant Chemoradiation Therapy for Pancreatic Adenocarcinoma: Who Really Benefits?” Journal of the American College of Surgeons 208, no. 5 (May 2009): 829–38; discussion 838-841. PMID: 19476845.



Our Patient Satisfaction Rating is an average of all responses to care provider related questions from our nationally-recognized Press Ganey Patient Satisfaction Survey. Learn more.


4.9 / 5.0


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  • 5.0
    March 25, 2022
    Doctor and staff were very caring people and I was treated with respect.
  • 5.0
    January 07, 2022
    Dr. Castellanos went over and above to help us. He even got an opinion for us from another dr. He spent more than adequate time with us too.
  • 5.0
    November 13, 2021
    Dr. Castellanos is always accessible and available. He's kind and considerate of my needs as well as my family. I feel fortunate that Dr. Castellanos is my surgeon.
  • No Star Ratings Available October 22, 2021
    He is great!
  • 5.0
    October 15, 2021
    I was treated with upmost care & respect.
  • 5.0
    July 24, 2021
    The doctor is a caring person. He went over and beyond what any doctor ever treated me.
  • 5.0
    July 20, 2021
    Dr. Castellanos was discussing liver surgery as treatment for my neuroendocrine metastases liver tumors. I wanted it soon & the surgery was performed on [...], and I am now home, with that all over with. My time clock is reset, and I'm VERY happy! I feel that Dr. Castellanos did an excellent surgery & was always a pleasure to see afterward in the hospital visit. He certainly complied!
  • No Star Ratings Available June 17, 2021
    Dr Castellanos is fabulous!
  • 5.0
    May 20, 2021
    Very compassionate.
  • 5.0
    April 19, 2021
    Excellent care, excellent staff. Thank you!

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