Josiah An, MD

I speak: English, Korean
My gender: Male
Where I practice
- Emergency service
- Urgent care services
- After-hours services
- Pharmacy services
- No emergency services
- No urgent care services
- No after-hours services
- No pharmacy services
About me
Welcome to my Web page. I am happy to have this opportunity to introduce myself and share more about my practice.
Biography
I am a board-certified medical oncologist practicing at Kaiser Permanente’s Bellflower Medical Offices in the Hematology and Oncology Department. My approach to cancer care is rooted in precision medicine, ensuring that each member receives an individualized treatment plan tailored to his or her unique needs.
About my practice
My Cancer Subspecialty Focus
My primary focus is sarcoma oncology, specializing in the treatment of soft tissue and bone cancers. I have a clinical interest in gastrointestinal oncology, with a focus on stomach, liver, pancreatic, and colorectal cancers.
National Expertise on Multidisciplinary Teams
I serve as a regional expert on the Southern California Regional Sub-Specialty Sarcoma Oncology Committee, where I collaborate with radiation oncologists, surgical oncologists, pathologists, and other specialists to develop treatments based on evidence and current research. Additionally, I contribute to clinical research and data analysis on emerging therapies, which have been integrated into the National Kaiser Permanente Oncology Care Pathways. I also participate as a core member of the multidisciplinary Sarcoma Tumor Board, helping to ensure a comprehensive, team-based approach to complex sarcoma cases.
Research and Clinical Trials
I am a proud member of several prestigious oncology research groups, including the National Cancer Institute Community Oncology Program and the American Society of Clinical Oncology. As a sub-investigator, I actively participate in clinical trials through the following major research networks:
- SWOG Cancer Research Network
- National Surgical Adjuvant Breast and Bowel Project (NSABP)
- Alliance for Clinical Trials in Oncology
- NRG Oncology
My research involvement also includes collaboration with these leading oncology research networks. My work aims to advance cancer treatment options and improve member outcomes.
How I thrive
Outside of my practice, I strive to maintain a healthy balance between professional and personal life. I enjoy staying active, exploring new advancements in oncology, and spending quality time with family and friends.
My office
Languages spoken by medical staff
Help is available in your language. Learn more.
My provider type
Physicians and SurgeonsMedical groups, plans, and locations
Southern California Permanente Medical Group
Plans accepted
- Exclusive Provider Organization (EPO)
- HMO
- Medi-Cal Managed Care
- Point-of-Service Plan (POS)
- Senior Advantage
Bellflower Medical Offices - Mob 1
Contact information
- Advice/appointments/cancellations/messages
- 1-833-574-2273 (toll free)
- Appointments/information
- 1-800-800-7990 (toll-free TTY for the hearing/speech impaired)
My training, certifications and licensing
Medical school
Southern Illinois University School of MedicineBoard certification
Hematology
American Board of Internal MedicineInternal Medicine
American Board of Internal MedicineMedical Oncology
American Board of Internal MedicineMedical training
Fellowship
Hematology and Oncology
University of Iowa Hospitals and ClinicsResidency
Internal Medicine
University of Iowa Hospitals and ClinicsJoined Permanente Medical Group
2024Active license information
License number
A192360License type
Physician and SurgeonLicense issuing state
CALIFORNIANational Provider Identifier (NPI)
1053791517Cultural Competency Training (CCT)
PendingMy hospitals
All Kaiser Permanente physicians and podiatrists have admitting privileges or the ability to refer patients to our plan hospitals. Admitting privileges of other providers may vary by plan and facility. Contact your plan administrator for details.
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This page was last updated on: 04/27/2025