Katie A. Greenzang, M.D.
Pediatric Hematology & Oncology Physician · Boston, MA
Katie A. Greenzang, M.D. is a pediatric hematology & oncology physician with a practice address in Boston, Massachusetts, and NPI 1437391000, issued on Mar 29, 2009. Check the license (Massachusetts 254298, as entered in NPPES) on the Massachusetts Board of Registration in Medicine; the Medicare figures below come from public CMS files.
- Name
- Katie A. Greenzang
- Credential
- M.D.
- Primary taxonomy
- Pediatric Hematology & Oncology Physician 2080P0207X
- License number
- 254298 MA
Self-reported in NPPES; status is on the state search - Practice location
- 450 Brookline Ave, Boston, MA 02215
- Phone
- (617) 632-3352
- Enumerated
- Mar 29, 2009
- Record last updated
- Feb 13, 2014 (not updated in 12 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20160623001243); accepts Medicare assignment
- Medical or professional school
- Columbia University College Of Physicians And Surgeons, 2009
- Entity
- Type 1 · individual
8 nearest pediatric hematology & oncology physician records → All 197 in Massachusetts → Look up another NPI →
Also registered at 450 Brookline Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Gregory Abel, MDHematology & Oncology Physician1285611954
- Lara Abousamra, PHARMDPharmacist Clinician (PhC)/ Clinical Pharmacy Specialist1851183404
- Karley Adams, PAPhysician Assistant1578261764
- Lauren Adams, PA-CPhysician Assistant1902763469
- Ana Aguilar-Bonilla, M.D.Pediatric Hematology & Oncology Physician1023319761
- Andrew Aguirre, MD, PHDMedical Oncology Physician1609071208
Verify Katie A. Greenzang in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMassachusetts Board of Registration in Medicine
Search for license 254298Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Bills Medicare through one group practice
- Dana-Farber Cancer Institute, Inc.Boston, MA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Katie A. Greenzang among 197 pediatric hematology & oncology physician records in Massachusetts
Katie A. Greenzang, M.D. is one of 197 pediatric hematology & oncology physician records with a practice address in Massachusetts. 42% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2009, is newer than 56% of them.
- NPI issued2009 · 56% of these records are older, 40% newer
- In a Medicare fileYes · 42% of these records are
- In the CMS Doctors and Clinicians fileYes · 28% of these records are
- Graduated2009 · median 2007 among the 55 with a school on file
- Record last updated2014 · 65% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2080P0207X and a Massachusetts practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Pediatric Hematology & Oncology Physician providers in Massachusetts
There are 197 pediatric hematology & oncology physician records in Massachusetts.
All 197 in Massachusetts → Every provider in Boston → Pediatric Hematology & Oncology Physician nationwide →
The 8 pediatric hematology & oncology physician records with the nearest ZIP codes
- Natasha Archer, MDBoston, MA 022151346376779
- Steven Dubois, M.D.Boston, MA 022151992746911
- Rani George, MD PHDBoston, MA 022151346217932
- William Haining, MDBoston, MA 022151235192758
- John Horan, MD MPHBoston, MA 022151649224502
- Amy Keating, MDBoston, MA 022151447335195
- Elizabeth Mullen, MD, FAAPBoston, MA 022151376511477
- Yana Pikman, MDBoston, MA 022151669659116
Common questions
What is Katie A. Greenzang, M.D.'s NPI number?
Katie A. Greenzang, M.D.'s National Provider Identifier (NPI) is 1437391000, issued on Mar 29, 2009. An NPI identifies a provider in billing; it is not a license.
Where is Katie A. Greenzang, M.D. located?
The NPPES record lists a practice address at 450 Brookline Ave, Boston, MA, 02215. Phone: (617) 632-3352. Providers update this record themselves, so call before visiting.
How can I verify Katie A. Greenzang, M.D.'s license?
NPPES lists Massachusetts license number 254298, as entered by the provider. Search the Massachusetts Board of Registration in Medicine at https://findmydoctor.mass.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
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.