Maria Perez Grau, MD
NPI 1821065855 · Hematology & Oncology Physician · San Juan, PR
Enrolled with Medicare as Practitioner - Hematology/Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Maria Perez Grau, MD is a Hematology & Oncology Physician provider in San Juan, PR (NPI 1821065855).
Provider details
- NPI number
- 1821065855
- Entity type
- Individual
- Primary specialty
- Hematology & Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- Yes
- License
- 13570 (PR)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
61 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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 61 | $125 |
Typical Medicare-allowed amounts for these services range $125–$125 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 39 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Anastrozole | 273 | 53 |
| Famotidine | 97 | 44 |
| Enzalutamidebrand: Xtandi | 82 | — |
| Warfarin Sodium | 75 | 11 |
| Ondansetron Hcl | 60 | 36 |
| Rivaroxabanbrand: Xarelto | 49 | 13 |
| Bicalutamide | 45 | — |
| Abemaciclib |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$983 across 43 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
Registry dates
- Enumerated
- 2006-03-08
- Last updated
- 2019-01-15
Frequently asked questions
- What is Maria Perez Grau's NPI number?
- Maria Perez Grau's National Provider Identifier (NPI) is 1821065855, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Maria Perez Grau's specialty?
- Maria Perez Grau is listed in the NPPES registry with a primary specialty of Hematology & Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Maria Perez Grau located?
- Maria Perez Grau's practice location on file with NPPES is 1429 Ave Fernandez Juncos, San Juan, PR 00909-2658.
- What is Maria Perez Grau's phone number?
- The practice phone number listed in the NPPES registry for Maria Perez Grau is (787) 946-4401.
- Does Maria Perez Grau accept Medicare?
- Maria Perez Grau is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Maria Perez Grau's NPI active?
- Yes — Maria Perez Grau's NPI (1821065855) is active in the NPPES registry as of the last update on 2019-01-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.