Ruben Fragoso, M.D., Ph.D.

Ruben Fragoso, M.D., Ph.D.


  • Associate Professor


To see if Ruben Fragoso is accepting new patients, or for assistance finding a UC Davis doctor, please call 800-2-UCDAVIS (800-282-3284).

UC Davis Comprehensive Cancer Center

4501 X St., G-140
Sacramento, CA 95817
Driving Directions

Primary Phone:

Additional Phone Numbers

Clinic Phone: 916-734-5810
Clinic Fax: 916-703-5068
Clinic Referral Phone: 800-362-5566
Physician Referrals: 800-4-UCDAVIS (800-482-3284)

Philosophy of Care

Undergoing radiation treatments can be scary and overwhelming. Each patient has a unique situation involving their specific diagnosis and the treatment of their disease. It is important to recognize the patient’s unique issues in order to provide care for the patient as a whole person. It is also important to help patients understand their diagnosis so that they can make more informed decisions and understand their care.

Clinical Interests

Dr. Fragoso's main clinical activities involve the treatment of both benign and malignant central nervous tumors that can arise in the adult and pediatric populations. Radiation treatment techniques include Gamma Knife radiosurgery and fractionated radiation radiotherapy (3D or IMRT). Medical interests revolve around the better understanding of gliomas, particularly high grade gliomas.

Glioblastoma multiforme (GBM), a WHO grade IV glioma, carries a poor prognosis for which there have been modest therapeutic advances. My area of interest and research is focused on targeting specific cancer cells that are thought to perpetuate the tumor within the GBM itself. These "cancer stem cells" tend to be resistant to treatment. We are studying ways in which these cells can be targeted specifically and destroyed.


Radiation Oncology

Center/Program Affiliation

UC Davis Comprehensive Cancer Center


M.D., Harvard Medical School, Boston MA 2004

Ph.D., Harvard Medical School, Boston MA 2004

B.A., Princeton University, Princeton NJ 1992

Internship: Internal Medicine, Morristown Memorial Hospital, Morristown NJ 2005


Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia PA 2009

Board Certifications

American Board of Radiology,

Professional Memberships

American Association of Cancer Research

American College of Radiation Oncology

American Society of Therapeutic Radiology and Oncology

Select Recent Publications

Chen H, Nguyen KNB, Huang H, Feng C, Zhao X, Daly ME, Rao S, Fragoso R, Valicenti R, Sekhon S, Navarro SM, Kim EJ, Cho M, Tam K, Farkas L, Halabi WJ, Monjazeb AM, Rong Y. Effect and Safety of Radiation Therapy Boost to Extramesorectal Lymph Nodes in Rectal Cancer. Pract Radiat Oncol. 2020 Sep-Oct;10(5):e372-e377. doi:10.1016/j.prro.2019.12.007. Epub 2019 Dec 20. PMID:31866577.

Xie B, Zhang L, Hu W, Fan M, Jiang N, Duan Y, Jing D, Xiao W, Fragoso RC, Lam KS, Sun LQ, Li JJ. Dual blockage of STAT3 and ERK1/2 eliminates radioresistant GBM cells. Redox Biol. 2019 Jun;24:101189. doi:10.1016/j.redox.2019.101189. Epub 2019 Apr 9. PMID:30986607.

McGee HM, Daly ME, Azghadi S, Stewart SL, Oesterich L, Schlom J, Donahue R, Schoenfeld JD, Chen Q, Rao S, Fragoso RC, Valicenti RK, Canter RJ, Maverakis EM, Murphy WJ, Kelly K, Monjazeb AM. Stereotactic Ablative Radiation Therapy Induces Systemic Differences in Peripheral Blood Immunophenotype Dependent on Irradiated Site. Int J Radiat Oncol Biol Phys. 2018 Aug 1;101(5):1259-1270. doi:10.1016/j.ijrobp.2018.04.038. Epub 2018 Apr 22. PMID:29891204.

Hartl BA, Ma HSW, Sridharan S, Hansen KS, Kent MS, Gorin F, Fragoso RC, Marcu L. Label-free fluorescence lifetime spectroscopy detects radiation-induced necrotic changes in live brain in real-time. Biomed Opt Express. 2018 Jul 5;9(8):3559-3580. doi:10.1364/BOE.9.003559. eCollection 2018 Aug 1. PMID:30338140.

Yuan Z, Nair CK, Benedict SH, Valicenti RK, Rao S, Fragoso RC, Wright C, Qiu J, Rong Y. Converting Treatment Plans From Helical Tomotherapy to L-Shape Linac: Clinical Workflow and Dosimetric Evaluation. Technol Cancer Res Treat. 2018 Jan 1;17:1533033818785279. doi:10.1177/1533033818785279. PMID:29986638.

Hartl BA, Ma HSW, Hansen KS, Perks J, Kent MS, Fragoso RC, Marcu L. The effect of radiation dose on the onset and progression of radiation-induced brain necrosis in the rat model. Int J Radiat Biol. 2017 Jul;93(7):676-682. doi:10.1080/09553002.2017.1297902. Epub 2017 Mar 17. PMID:28306402.

Yoshida E, Aouad R, Fragoso R, Farwell DG, Gandour-Edwards R, Donald PJ, Chen AM. Improved clinical outcomes with multi-modality therapy for sinonasal undifferentiated carcinoma of the head and neck. Am J Otolaryngol. 2013 Nov-Dec;34(6):658-63. doi:10.1016/j.amjoto.2013.06.005. Epub 2013 Aug 29. PMID:23993024.

Shen X, Andrews DW, Sergott RC, Evans JJ, Curran WJ, Machtay M, Fragoso R, Eldredge H, Champ CE, Witek M, Mishra MV, Dicker AP, Werner-Wasik M. Fractionated stereotactic radiation therapy improves cranial neuropathies in patients with skull base meningiomas: a retrospective cohort study. Radiat Oncol. 2012 Dec 28;7:225. doi:10.1186/1748-717X-7-225. PMID:23270432.

Donaldson JM, Kari C, Fragoso RC, Rodeck U, Williams JC. Design and development of masked therapeutic antibodies to limit off-target effects: Application to anti-EGFR antibodies. Cancer Biol Ther. 2009 Nov;8(22):2147-52. doi:10.4161/cbt.8.22.9765. Epub 2009 Nov 7. PMID:19783899.

Fragoso RC, Pyarajan S, Irie HY, Burakoff SJ. A CD8/Lck transgene is able to drive thymocyte differentiation. J Immunol. 2006 Nov 1;177(9):6007-17. doi:10.4049/jimmunol.177.9.6007. PMID:17056525.