Steven Siwei Yu, MD
Hematology & Oncology Physician · Fountain Valley, CA
Steven Siwei Yu, MD is a hematology & oncology physician with a practice address in Fountain Valley, California, and NPI 1659643682, issued on Feb 7, 2012. Check the license (California A122462, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Steven Siwei Yu
- Credential
- MD
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License number
- A122462 CA
Self-reported in NPPES; status is on the state search - Practice location
- 11180 Warner Ave Ste 351, Fountain Valley, CA 92708
- Phone
- (714) 698-0300
- Enumerated
- Feb 7, 2012
- Record last updated
- May 21, 2025
- Fax
- (714) 698-0313
- Medicaid ID
- 1659643682 CA
- Medicare enrollment
- Enrolled (PECOS I20170613001153); accepts Medicare assignment
- Medical or professional school
- Medical University Of South Carolina College Of Medicine, 2011
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 1,583 in California → Look up another NPI →
Also registered at 11180 Warner Ave Ste 351
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Kevin DoHematology & Oncology Physician1811384001
- Jenny JooAdult Health Nurse Practitioner1821411570
- Eric Lee, M.D., PH.D.Hematology & Oncology Physician1609211838
- Hannah Manning, PA-CMedical Physician Assistant1780378521
- Janet Pan, M.D.Specialist1801056676
- Pete Pow-AnpongkulHematology & Oncology Physician1831586387
Verify Steven Siwei Yu in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A122462Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
17% more Medicare Part D claims than the average hematology & oncology physician in 2024
1,022 Medicare Part D claims for 185 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D. Brand-name drugs were 41% of claims. 25 claims were for opioids.
Most prescribed
- Eliquis80 claims
- Amlodipine Besylate43 claims
- Alendronate Sodium37 claims
- Tamoxifen Citrate36 claims
- Ondansetron Hcl35 claims
- Anastrozole33 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $6,307.50
270 payments; by number, the most common kind was food and beverage; the largest payer was AstraZeneca Pharmaceuticals LP. The 8,560 providers of this specialty with any payment received $7,481.41 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Los Angeles Hematology-Oncology Medical GroupFountain Valley, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Steven Siwei Yu among 1,583 hematology & oncology physician records in California
Steven Siwei Yu, MD is one of 1,583 hematology & oncology physician records with a practice address in California. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2012, is newer than 75% of them.
- NPI issued2012 · 75% of these records are older, 21% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 71% of these records are
- Graduated2011 · median 2003 among the 1,124 with a school on file
- Record last updated2025 · 58% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RH0003X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Hematology & Oncology Physician providers in California
There are 1,583 hematology & oncology physician records in California.
All 1,583 in California → Every provider in Fountain Valley → Hematology & Oncology Physician nationwide →
The 8 hematology & oncology physician records with the nearest ZIP codes
- Sarah Hassan, M.DFountain Valley, CA 927081689935066
- Jack Jacoub, M.D.Fountain Valley, CA 927081528016318
- Eric Lee, M.D., PH.D.Fountain Valley, CA 927081609211838
- Rufina Pamela Mae Miel, MDFountain Valley, CA 927081063470391
- Robert Moss, M.D.Fountain Valley, CA 927081861503609
- Gurpreet Multani, MDFountain Valley, CA 927081417117979
- Bichlien Nguyen, M.D.Fountain Valley, CA 927081417912239
- Lalita Pandit, M.D.Fountain Valley, CA 927081578521266
Common questions
What is Steven Siwei Yu, MD's NPI number?
Steven Siwei Yu, MD's National Provider Identifier (NPI) is 1659643682, issued on Feb 7, 2012. An NPI identifies a provider in billing; it is not a license.
Where is Steven Siwei Yu, MD located?
The NPPES record lists a practice address at 11180 Warner Ave Ste 351, Fountain Valley, CA, 92708. Phone: (714) 698-0300. Providers update this record themselves, so call before visiting.
How can I verify Steven Siwei Yu, MD's license?
NPPES lists California license number A122462, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Steven Siwei Yu, MD prescribe under Medicare Part D?
In 2024, Steven Siwei Yu, MD had 1,022 Medicare Part D claims for 185 beneficiaries; the average among hematology & oncology physician prescribers was 877. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.