Warren Lok, MD
I speak: English
My gender: Male
Where I practice
About me
Welcome to my Web page. I am a board-certified medical oncologist, and I care for members with a wide variety of blood disorders and solid tumors. I feel fortunate to practice in a department with supportive colleagues and dedicated staff who work together to provide high-quality, compassionate care for our members.
Biography
I am a native of Southern California, although I attended college in Northern California before spending several years in the Northeast for medical school and clinical training. After completing my training, I chose to return to Southern California to be closer to family and raise my children.
Outside of medicine, I enjoy spending time outdoors with my boys and taking advantage of the many activities Southern California has to offer.
About my practice
A cancer diagnosis can bring many challenges for members and their families. My goal is to guide members through this journey by providing clear information, compassionate care, and thoughtful treatment planning. I strive to help members understand their disease and their treatment options while supporting quality of life throughout their care.
My Cancer Subspecialty Focus
My clinical focus includes the care of those with solid tumors and hematologic disorders, including both benign and malignant blood conditions. I work with members to develop individual treatment plans that include the latest advances in cancer therapy while aligning with each member’s personal goals and needs.
Regional Expertise on Multidisciplinary Teams
I work closely with multidisciplinary teams that include specialists in medical oncology, hematology, radiation oncology, pathology, surgery, and supportive care services. This approach helps ensure that members receive comprehensive treatment that is based on evidence and current research and is aligned with national best practices.
Research and Clinical Trials
I participate in clinical research initiatives designed to advance cancer care and expand treatment options for members. Through involvement in national oncology research collaborations and clinical trials, I help bring innovative therapies and emerging treatments to our community.
How I thrive
My family is my top priority. Outside of family activities, I enjoy jogging and traveling. Both my professional experiences and personal life have helped me maintain a balanced perspective and appreciation for what matters most.
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
Market Street Medical Offices
Contact information
- Appointments/Cancellations/Information
- 1-833-574-2273 (toll free)
Notifications
- Provider offers telehealth services.
- Provider offers services at multiple medical facilities; schedule availability may vary by location.
Woodland Hills Medical Center
Contact information
- Appointments/cancellations/messages
- 1-833-574-2273 (toll free)
- California Relay Service
- 711 (TTY for the hearing/speech impaired)
- General information
- 818-719-2000
- Inpatient room information
- 818-719-2770
Notifications
- Provider offers telehealth services.
- Provider offers services at multiple medical facilities; schedule availability may vary by location.
My training, certifications and licensing
Medical school
Boston University School of MedicineBoard certification
Medical Oncology
American Board of Internal MedicineMedical training
Fellowship
Medical Oncology
Yale New Haven HospitalInternship
Internal Medicine
University Hospitals of ClevelandResidency
Internal Medicine
University Hospitals of ClevelandJoined Permanente Medical Group
2010Active license information
License number
A113540License type
Physician and SurgeonLicense issuing state
CALIFORNIANational Provider Identifier (NPI)
1962658344Cultural Competency Training (CCT)
CompletedMy hospitals
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Kaiser Permanente uses the same quality, member experience, or cost-related measures to select practitioners and facilities in Marketplace Silver-tier plans as it does for all other Kaiser Foundation Health Plan (KFHP) products and lines of business. The measures may include, but are not limited to, HEDIS/CAHPS performance, member/patient complaints, patient safety scores, hospital quality measures, and geographic need. Members enrolled in KFHP Marketplace plans have access to all professional, institutional and ancillary health care providers who participate in KFHP plans’ contracted provider network, in accordance with the terms of members’ KFHP plan of coverage. All Kaiser Permanente Medical Group physicians and network physicians are subject to the same quality review processes and certifications.
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This page was last updated on: 05/03/2026