Mark Sittig, MD
NPI 1275951519 · Radiation Oncology Physician · Nashville, TN
Enrolled with Medicare as Practitioner - Radiation Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Sittig, MD is a Radiation Oncology Physician provider in Nashville, TN (NPI 1275951519).
Provider details
- NPI number
- 1275951519
- Entity type
- Individual
- Primary specialty
- Radiation Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 59257 (TN)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
12 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
2,081 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Ct Guidance for Insertion of Radiation Therapy Fields77014 | 817 | $41 |
| Calculation of Radiation Therapy Dose77300 | 228 | $30 |
| Radiation Treatment Management, 5 Treatment Sessions77427 | 201 | $173 |
| Stereoscopic X-Ray Guidance for Localization of Target Volume for the Delivery of Radiation TherapyG6002 | 190 | $19 |
| Design and Construction of Complex Radiation Treatment Device77334 | 108 | $56 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 94 | $89 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 4 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Tamsulosin Hcl | 46 | 17 |
| Oxybutynin Chloridebrand: Oxybutynin Chloride Er | 18 | — |
| Gabapentin | 14 | — |
| Mometasone Furoate | 12 | — |
Medicare Part D only. These counts cover prescriptions paid through Medicare Part D in 2024 — they do notinclude cash-pay, commercial-insurance, Medicaid, or Part B–administered drugs, and badly undercount high cash-pay categories (e.g. GLP-1 weight-loss, testosterone, and ED medications). Any drug with 10 or fewer claims is omitted by CMS, and beneficiary counts under 11 are suppressed — so a missing drug means no Part D record, never zero. This is a factual claims summary, not an endorsement, not medical advice, and not a consumer report. Source: CMS Medicare Part D Prescribers — by Provider and Drug.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$711 across 6 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 2801 Charlotte AveNashville, TN 37209-4035Phone: (615) 250-9200
Registry dates
- Enumerated
- 2014-04-03
- Last updated
- 2026-02-25
- Certified
- 2026-02-25
Frequently asked questions
- What is Mark Sittig's NPI number?
- Mark Sittig's National Provider Identifier (NPI) is 1275951519, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Sittig's specialty?
- Mark Sittig is listed in the NPPES registry with a primary specialty of Radiation Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Sittig located?
- Mark Sittig's practice location on file with NPPES is 2004 Hayes St Ste Ll15, Nashville, TN 37203-2647.
- What is Mark Sittig's phone number?
- The practice phone number listed in the NPPES registry for Mark Sittig is (615) 284-7785.
- Does Mark Sittig accept Medicare?
- Mark Sittig is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Sittig's NPI active?
- Yes — Mark Sittig's NPI (1275951519) is active in the NPPES registry as of the last update on 2026-02-25.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.