William Sikov, MD
Hematology & Oncology Physician · Providence, RI
William Sikov, MD is a hematology & oncology physician with a practice address in Providence, Rhode Island, and NPI 1811916661, issued on Jul 19, 2006. Check the license (Rhode Island MD7581, as entered in NPPES) on the Rhode Island Board of Medical Licensure and Discipline; the Medicare figures below come from public CMS files.
- Name
- William Sikov
- Credential
- MD
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License number
- MD7581 RI
Self-reported in NPPES; status is on the state search - Practice location
- 1 Blackstone Street, Providence, RI 02903
- Phone
- (401) 453-7520
- Enumerated
- Jul 19, 2006
- Record last updated
- Jun 16, 2021 (not updated in 5 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20060113000456); accepts Medicare assignment
- Medical or professional school
- Yale University School Of Medicine, 1982
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 88 in Rhode Island → Look up another NPI →
Also registered at 1 Blackstone Street
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Marcina Beaston-Casey, MS, CGCGenetic Counselor (M.S.)1548023203
- Ariana Carvajal, WHNPWomen's Health Nurse Practitioner1912438581
- Stephanie Cheves, NPGerontology Nurse Practitioner1376136077
- Marc Houle, PTPhysical Therapist1578574893
- Mohammed Jaloudi, MDMedical Oncology Physician1194249565
- Cara Mathews, MDObstetrics & Gynecology Physician1659540490
Verify William Sikov in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersRhode Island Board of Medical Licensure and Discipline
Search for license MD7581Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
97% fewer Medicare Part D claims than the average hematology & oncology physician in 2024
24 Medicare Part D claims for 17 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D.
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: $1,686.56
12 payments; by number, the most common kind was food and beverage; the largest payer was AstraZeneca UK Limited. 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
- Affinity Physicians LLC.Warwick, RI
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William Sikov among 88 hematology & oncology physician records in Rhode Island
William Sikov, MD is one of 88 hematology & oncology physician records with a practice address in Rhode Island. 85% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 15% of them.
- NPI issued2006 · 15% of these records are older, 53% newer
- In a Medicare fileYes · 85% of these records are
- In the CMS Doctors and Clinicians fileYes · 73% of these records are
- Graduated1982 · median 2002 among the 64 with a school on file
- Record last updated2021 · 52% 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 Rhode Island 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 Rhode Island
There are 88 hematology & oncology physician records in Rhode Island.
All 88 in Rhode Island → Every provider in Providence → Hematology & Oncology Physician nationwide →
The 8 hematology & oncology physician records with the nearest ZIP codes
- Ariel Birnbaum, M.D.Providence, RI 029031942212790
- James Butera, M.D.Providence, RI 029031790797538
- Maria Constantinou, MDProvidence, RI 029031407999444
- Wafik El Deiry, MDProvidence, RI 029031275575714
- Katherine Faricy-Anderson, MD MPHProvidence, RI 029031194940700
- Mary Anne Fenton, M.D.Providence, RI 029031881606622
- Humera Khurshid, MDProvidence, RI 029031013991926
- Adam Olszewski, M.D.Providence, RI 029031467436915
Common questions
What is William Sikov, MD's NPI number?
William Sikov, MD's National Provider Identifier (NPI) is 1811916661, issued on Jul 19, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William Sikov, MD located?
The NPPES record lists a practice address at 1 Blackstone Street, Providence, RI, 02903. Phone: (401) 453-7520. Providers update this record themselves, so call before visiting.
How can I verify William Sikov, MD's license?
NPPES lists Rhode Island license number MD7581, as entered by the provider. Search the Rhode Island Board of Medical Licensure and Discipline at https://healthri.mylicense.com/Verification/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does William Sikov, MD prescribe under Medicare Part D?
In 2024, William Sikov, MD had 24 Medicare Part D claims for 17 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.