Ritesh Parajuli
Biography
Ritesh Parajuli, M.D., is Associate Clinical Professor Step II in the Department of Medicine, Division of Hematology/Oncology at the University of California, Irvine. He received his Bachelor of Medicine and Bachelor of Surgery (MBBS) from Manipal College of Medical Sciences in Nepal, completed his Internal Medicine residency at Rosalind Franklin University of Medicine and Sciences, and his Hematology Oncology fellowship at the University of Miami/Jackson Memorial Hospital. Parajuli serves as Chair of the Breast Disease Oriented Team at UCI and has held multiple administrative roles including Medical Director of the Infusion Center at the Chao Family Comprehensive Cancer Center.
Parajuli's research focuses on circulating biomarkers in breast cancer, particularly circulating cancer-associated fibroblasts (cCAFs) and circulating tumor cells as prognostic markers for metastasis. He has developed multiple investigator-initiated clinical trials examining novel therapeutic approaches in breast cancer, including studies of CDK4/6 inhibitors, PARP inhibitors, and antibody-drug conjugates. His work on isolating and characterizing circulating cells from the tumor microenvironment has been published in journals including Cancer Research and Lab on a Chip. He has served as principal investigator on numerous industry-sponsored and cooperative group trials, and as site PI for ETCTN trials through the National Cancer Institute.
Parajuli has mentored over 15 fellows and medical students in translational breast cancer research, with several trainees receiving Department of Medicine Trainee Grants and presenting their work at national conferences. He is a member of professional societies including the American Society of Clinical Oncology, American Society of Hematology, and serves on the NRG Breast Cancer Translational Research Subcommittee and SWOG Breast Committee. Through the American Society of Clinical Oncology's Health Volunteer Overseas program, he has provided volunteer teaching to medical oncology fellows and physicians at the National Academy of Medical Sciences in Kathmandu, Nepal.
Return to topEducation
- Intermediate in Science, St Xavier's Campus, Kathmandu University, Nepal, 1996
- MBBS, Manipal College of Medical Sciences, Pokhara, Nepal, 2003
Distinctions
- Selected as a mentor for the NCI T35 ICTS Summer Mentoring and Research Training Award (SMART), 2021
- NCI CTEP/Early Career Investigator LOI Writing Workshop, Accepted as an ECI, 2022
- UCI CFCCC Oncology Summer Internship, UIRM (Underrepresented in medicine): Exemplary Faculty (Teaching) Award, 2022
Areas of Expertise
- Breast Cancer Oncology
- Circulating Tumor Biomarkers
- Tumor Microenvironment Characterization
- CDK4/6 Inhibitor Therapy
- HER2-Targeted Antibody Conjugates
- Neoadjuvant Immunotherapy Combinations
- PIK3CA Mutation Targeting
Recent Publications
- Hurvitz S.A., Loi S., O'Shaughnessy J., Okines A.F.C., Tolaney S.M., Sohn J., Saura C., Zhu X., Cameron D., Bachelot T., Hamilton E., Curigliano G., Wolff A.C., Harbeck N., Masuda N., Vahdat L., Zaman K., Valdes-Albini F., Block M., Pluard T., et al., “Tucatinib and trastuzumab emtansine for patients with previously treated HER2-positive locally advanced and metastatic breast cancer: primary analysis of the randomized phase III trial HER2CLIMB-02☆” (opens in new tab), Annals of Oncology, vol. 37, pp. 341-352, 2026.
- Nafissi N., Mahadevan A., Chiao E., Rijal N., Parajuli R., “Triple Negative Breast Cancer With Choroidal Metastasis Responsive to Sacituzumab Govitecan and Radiation Therapy” (opens in new tab), Cancer Reports, vol. 9, 2026.
- Speck R.M., Harding G., Chawla A.R., Agius C.R., Bahadur S.W., Hudson K., Jaloudi M.A., Parajuli R., Vidal G.A., Bacci E.D., “Qualitative Interviews on the Experience of Orally vs. Intramuscularly Administered Endocrine Therapy for Advanced Breast Cancer: Patient and Healthcare Provider Perspectives” (opens in new tab), Oncology and Therapy, 2025.
- Jhaveri KL, Lim E, Jeselsohn R, Ma CX, Parajuli R, Ismail-Khan R, Smyth, Beeram M, “Imlunestrant, an Oral Selective Estrogen Receptor Degrader, as Monotherapy and in combination with Targeted therapy in Estrogen receptor positive, Her-2 negative Advanced Breast Cancer: Phase Ia/Ib Ember study” (opens in new tab), Journal of Clinical Oncology, vol. 42, no. 35, pp. 3173-4186, 2024.
- Lifang Xie, Ding Quan Ng, Matthew Heshmatipour, Munjal Acharya, Paul Coluzzi, Nerida Guerrero, Sanghoon Lee, Shaista Malik, Ritesh Parajuli, Craig Stark, Rongwen Tain, Keri Zabokrtsky, Lilibeth Torno, Alexandre Chan, “Electroacupuncture for the Management of Symptom Clusters in Cancer Patients and Survivors (EAST)” (opens in new tab), BMC Complementary Medicine and Therapies, vol. 23, 2023.
- Brazel D, Lee S, Mahadevan A, Warnecke B, Parajuli R, “Multiorgan Failure from Nivolumab and Ipilimumab: A Case report and literature review”, Cureus, 2023.
- Mahadevan A, Warnecki B, Chiao E, Nafissi N, Parajuli K, Rijal N, Parajuli R, “Goserelin-Induced Chemical Burn: A Case report and review of the literature”, Cureus, 2023.
- Jiang R., Chen Y.-H., Parajuli R., Agrawal A., Lee A.P., “3D Centrifugation-Enabled Priming of Synaptic Activation Promotes Primary T Cell Expansion” (opens in new tab), Advanced Therapeutics, vol. 6, 2023.
Most Cited Publications
- Nagajothi N, Khraisat A, Velazquez-Cecena JL, Arora R, Raghunathan K, Patel R, Parajuli R, “Energy Drink Related Supraventricular Tachycardia” (opens in new tab), American Journal of Medicine, vol. 121, no. 4, pp. e3-4, 2008.
- Barber E, Eapen A, Mehta R, Parajuli R, “Benign Metastasizing Leiomyoma to the Lung and Spine: A Case Report and Literature Review” (opens in new tab), Case Reports in Oncology, vol. 11, no. 2, pp. 360-364, 2018.
- Lyou Y., Barber E., Mehta R., Lee T., Goreal W., Parajuli R., “Radiation-Associated Angiosarcoma of the Breast: A Case Report and Literature Review” (opens in new tab), Case Reports in Oncology, vol. 11, pp. 216-220, 2018.
- Parajuli R, Hire E, Shah BK, “Rituximab induced acute and severe thrombocytopenia” (opens in new tab), British Journal of Haematology, vol. 149, no. 6, pp. 804, 2010.
- Yu Cheng, Ningjing Li, Ann Eapen, Ritesh Parajuli, Rita Mehta, “Somatic BRCA2 Mutation Positive Concurrent Male Accessory Breast Cancer (BC) and Non-Small Cell Lung Cancer (NSCLC): Excellent Efficacy of Palbociclib, Fulvestrant and Leuprolide in Platinum-Exposed and Endocrine Refractory BC with associated Cyclin D1 and FGFR1 Amplification and of Carboplatin, Paclitaxel and Radiation in NSCLC” (opens in new tab), Case Reports in Oncology, vol. 12, pp. 494-499, 2019.
- Barber E, Eapen A, Nabar R, Goreal W, Bunney J, Parajuli R, “Treatment of Sino nasal Undifferentiated Carcinoma with TPF and Concurrent Chemo-Radiation: Case Report and Literature Review” (opens in new tab), Case Reports in Oncology, vol. 12, pp. 199–204, 2019.
- Emily Baber, Yung Lyou, Rita Mehta, Erin Lin, Karen Lane, Ritesh Parajuli, “Orbital Metastases from Breast Cancer with BRCA-2 mutation: A Case Report and Literature Review” (opens in new tab), Case Reports in Oncology, vol. 11, no. 2, pp. 360-364, 2018.
- Parajuli R, Altman J, Kuzel T, Perdekamp M, Tallman M, “Renal Cell Carcinoma and Acute Promyelocytic Leukemia: A nonrandom association? Correspondence to the editor” (opens in new tab), American Journal of Hematology, vol. 85, no. 10, pp. 829, 2010.
This profile was created with the help of AI.
Last updated on 4/2/2026.