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RADIATION ONCOLOGY ASSOCIATES, PC
NPI 1013962836
Radiology - Radiation Oncology in Fairfax, VA

Active since May 23, 2006
8081 INNOVATION PARK DR, FAIRFAX, VA 22031(571) 472-0606(571) 472-0540 Get Directions Write a Review

NPPES record last updated: June 28, 2019. Verified against the NPPES registry weekly; last sync: November 01, 2026.

About Radiation Oncology Associates, Pc NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

RADIATION ONCOLOGY ASSOCIATES, PC (NPI 1013962836), doing business as John G. Mayer, Md, Phd, Pc, is a healthcare organization registered as a radiation oncology in Fairfax, Virginia and active in the NPI registry since May 2006. The organization lists Stella Hetelekidis, President, as its authorized official.

NPPES Registry Identity

NPI1013962836
Entity TypeOrganization
Primary Taxonomy2085R0001X
Legal Business NameRADIATION ONCOLOGY ASSOCIATES, PC
Location Address8081 INNOVATION PARK DRFairfax, VA 22031-4867
Mailing Address9568 Kings Charter Dr, Suite 202Ashland, VA 23005-0078 · (804) 266-8717 · Fax (804) 266-5677
Phone(571) 472-0606
Fax(571) 472-0540
Organization SubpartNo
Authorized OfficialStella HetelekidisPresident · (703) 776-3731
Enumeration DateMay 23, 2006
Last NPPES UpdateJune 28, 2019
✔ NPI 1013962836 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyRadiology · Radiation OncologyAllopathic & Osteopathic Physicians
Taxonomy Code2085R0001X
Definition
A radiologist who deals with the therapeutic applications of radiant energy and its modifiers and the study and management of disease, especially malignant tumors.
8081 INNOVATION PARK DR, Fairfax, VA 22031
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Other Names 1

Former Legal Business NameJohn G. Mayer, Md, Phd, Pc

Other Identifiers 1

Medicaid1013962836VA

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Radiation Oncology Associates, Pc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

26

Medicare enrollment records show 26 clinicians reassign Medicare billing to Radiation Oncology Associates, PC, which bills Medicare for the services they deliver. Of these, 13 practice at this address and 14 within 10 miles. Listed here are the 20 practicing nearest to this location.

Clinicians by Medicare Specialty 2

Radiation Oncology20
Nurse Practitioner6

Nearest to this location (20)

See all 26
Gopal Bajaj, M.D.
Radiation Oncology
NPI 1922063197
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Sarah Bhatt, DNP, FNP-BC
Nurse Practitioner
NPI 1912672858
8081 INNOVATION PARK DR STE 120
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Tobias Chapman, M.D.
Radiation Oncology
NPI 1588927016
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Ashish Chawla, M.D.
Radiation Oncology
NPI 1699777599
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Kevin Choe, MD
Radiation Oncology
NPI 1609043892
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Michael Eblan, MD
Radiation Oncology
NPI 1962795773
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Stella Hetelekidis, MD
Radiation Oncology
NPI 1467416693
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Samir Kanani, M.D.
Radiation Oncology
NPI 1558336719
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Daniel Kim, M.D., M.B.A.
Radiation Oncology
NPI 1437507274
8081 INNOVATION PARK DR
Fairfax, VA 22031
(714) 720-6065
✔ PECOS✔ Accepts MedicareSame address
Emily Kowalski, MD
Radiation Oncology
NPI 1376939017
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0540
✔ PECOS✔ Accepts MedicareSame address
Lonika Majithia, MD
Radiation Oncology
NPI 1376833624
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Kathryn Marqueen, MD
Radiation Oncology
NPI 1427678945
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Cheng-Chia Wu, MD, PHD
Radiation Oncology
NPI 1770926701
8081 INNOVATION PARK DR
Fairfax, VA 22031
(571) 472-0606
✔ PECOS✔ Accepts MedicareSame address
Andrea Lattimore, FNP-BC
Nurse Practitioner
NPI 1144929027
6354 WALKER LN STE 210
Alexandria, VA 22310
(703) 971-6900
✔ PECOS✔ Accepts Medicare7.3 mi
Blanca Luizaga, FNP-BC
Nurse Practitioner
NPI 1720786437
3523 COVERED BRIDGE LN
Woodbridge, VA 22192
(703) 414-9476
✔ PECOS✔ Accepts Medicare14 mi
Susan Boylan, MD
Radiation Oncology
NPI 1316906068
2280 OPITZ BLVD SUITE 120
Woodbridge, VA 22191
(703) 670-3349
✔ PECOS16 mi
Julie Littlejohn, NP
Nurse Practitioner
NPI 1457960528
44035 RIVERSIDE PKWY STE 300
Leesburg, VA 20176
(571) 350-8400
✔ PECOS✔ Accepts Medicare20 mi
Alexandra Lapple, NP-F
Nurse Practitioner
NPI 1023603693
411B PARK HILL DR
Fredericksburg, VA 22401
(540) 368-3917
✔ PECOS✔ Accepts Medicare40 mi
Christopher Johnson, M.D., PH.D.
Radiation Oncology
NPI 1619330289
3001 S HANOVER ST
Baltimore, MD 21225
(410) 350-3565
✔ PECOS✔ Accepts Medicare42 mi
Avani Rao, M.D.
Radiation Oncology
NPI 1295006567
850 W BALTIMORE ST
Baltimore, MD 21201
(410) 369-5200
✔ PECOS✔ Accepts Medicare43 mi
See all 26 clinicians

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Radiation Oncology Associates, PC's NPI number?

The NPI number for Radiation Oncology Associates, PC is 1013962836. It was assigned to this organization in the NPPES registry on May 23, 2006. The provider was formerly known as John G. Mayer, MD, Phd, PC.

Where is Radiation Oncology Associates, PC located?

Radiation Oncology Associates, PC is located at 8081 Innovation Park Dr, Fairfax, VA 22031. The listed phone number is (571) 472-0606.

What is Radiation Oncology Associates, PC's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Radiation Oncology, with taxonomy code 2085R0001X.

Is Radiation Oncology Associates, PC enrolled in Medicare?

Yes. Radiation Oncology Associates, PC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Radiation Oncology Associates, PC?

According to the CMS Revalidation Reassignment List (October 2026 release), 26 clinicians in 2 Medicare specialties reassign their Medicare billing to Radiation Oncology Associates, PC. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. The largest specialties are Radiation Oncology (20) and Nurse Practitioner (6). Of these, 13 practice at this address and 14 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Radiation Oncology Associates, PC was last updated on June 28, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.