Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Elena Nikou Theodosiou, MD

Individual provider Hematology & Oncology Physician · NPI 1891730982

Elena Nikou Theodosiou, MD practises Medical Oncology in Portsmouth, New Hampshire. Qualified in 1996, 30 years ago. Practices with St Peters Hospital of the City of Albany, a 268-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Maine, New Hampshire and New York.

Years since qualifying
30
Licensed in
ME, NH, NY
In the registry since
2006
Specialties on file
3
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

155 Borthwick Ave Ste 301
Portsmouth, NH 03801-7156
Phone: (603) 433-5226
Fax: (603) 433-4939
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 1300 Massachusetts Avenue, Troy, NY 12180-1628 — (518) 268-5060

Specialties & licences

Hematology & Oncology Physician (primary) Taxonomy 207RH0003X · Licence 16333 (NH)
Hematology & Oncology Physician Taxonomy 207RH0003X · Licence 016524 (ME)
Hematology & Oncology Physician Taxonomy 207RH0003X · Licence 290174 (NY)

Record details

NPI number1891730982
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedJune 20, 2006
Last updated in NPPESJune 9, 2021
Certification dateMay 25, 2021

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyMEDICAL ONCOLOGY
Medical schoolOTHER
Graduated 1996 (30 years in practice)
Group practice St Peters Hospital Of The City Of Albany — 268 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients32
Services billed 115 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $36 2 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at St Peters Hospital of the City of Albany

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 268 clinicians in the practice; 12 are shown here.

Other providers in Portsmouth