Thomas Cao, MD
Hematology & Oncology Physician in Elgin, Illinois. This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 11,215 in Hematology & Oncology Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
What the federal data shows
Thomas Cao, MD filed 1,570 Medicare Part D claims in 2023 as a Hematology & Oncology Physician in Elgin, Illinois.
- 2K
- Part D claims, 2023
- Likely
- board-certified (heuristic)
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Thomas Cao, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,570 Top 19% higher than 81% of 1,370,886 prescribers
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source CMS Medicare Part D Prescriber Public Use File · 2023
Thomas Cao, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation - signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Thomas Cao, MD?
Quality data not reportedPrimary specialty
Medicare Part D claims
Specialty distribution in Illinois
How Hematology & Oncology Physician compares to other specialties among Illinois providers
Largest specialties in Illinois (% of in-state providers)
Hematology & Oncology Physician ranks #66 among Illinois's specialties (0.2% of in-state providers)
Each bar is a specialty's share of the Illinois provider total, by primary NUCC taxonomy. The highlighted bar is Hematology & Oncology Physician; the long tail of smaller specialties is omitted for legibility.
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Hematology & Oncology Physician. Verify directly:
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
Thomas Cao, MD appears in the CMS NPPES registry as a Hematology & Oncology Physician provider holding MD credentials at 1435 NORTH RANDALL ROAD, Elgin, IL, 60123, with a listed phone of (847) 717-6860. NPI 1194797266 was issued on 02/03/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Cao most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.
Medicare Part D records for calendar year 2023 show 1,570 prescription claims written by this provider, covering 137 Medicare beneficiaries and totaling roughly $215K in drug spend. These figures capture only Medicare Part D, commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.
Hematology & Oncology Physician is a mid-sized specialty nationwide, with 11,215 enrolled providers across 54 states and an average of 847 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist, always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.
Practice Address
Provider Details
| NPI | 1194797266 |
|---|---|
| Specialty | Hematology & Oncology Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 02/03/2006 |
Verify this provider's license
PlainDoctor pulls this profile from the CMS NPPES public registry. Confirm Thomas Cao, MD's current license status, disciplinary history, and board certifications with the Illinois Department of Financial and Professional Regulation in Illinois before relying on this page for a clinical or care decision.
How we sourced this profile
Hospital and facility affiliations
Facilities where Thomas Cao, MD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" - a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Industry payments received (2024) - CMS Open Payments transparency data
The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for Thomas Cao, MD. Source: openpaymentsdata.cms.gov.
Total received
$715
Largest payer
Lilly USA, LLC
Most common payment type
Food and Beverage
Industry payments are not necessarily indicators of bias, they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.
License & disciplinary context - Illinois IDFPR 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~42K Illinois medical licensees in 2023 - they are NOT specific to Thomas Cao, MD. To verify Thomas Cao, MD's current license status, search the IDFPR public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
IDFPR publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the Illinois disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
Prescribing Breakdown
- 30-Day Fills
- 3,501
- Total Day Supply
- 95,669
- Generic Drug Cost
- $63K
- Antibiotic Claims
- 208
Patient Demographics
- Average Patient Age
- 70.9 years
- Avg HCC Risk Score
- 1.30
- Gender Split
- 53% female / 47% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Thomas Cao, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
159 claims
- Prednisone
Prednisone
72 claims
- Metoprolol Succinate
Metoprolol Succinate
67 claims
- Pantoprazole Sodium
Pantoprazole Sodium
65 claims
- Lisinopril 58
Lisinopril
58 claims
- Losartan Potassium 58
Losartan Potassium
58 claims
- Levofloxacin 47
Levofloxacin
47 claims
- Metformin Hcl 47
Metformin Hcl
47 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 159 |
| Prednisone | 72 |
| Metoprolol Succinate | 67 |
| Pantoprazole Sodium | 65 |
| Lisinopril | 58 |
| Losartan Potassium | 58 |
| Levofloxacin | 47 |
| Metformin Hcl | 47 |
| Amlodipine Besylate | 46 |
| Amoxicillin-Clavulanate Potass Amoxicillin/Potassium Clav | 38 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Hematology & Oncology Physician Overview
How Thomas Cao, MD fits within the Hematology & Oncology Physician landscape nationally.
Thomas Cao, MD's 1,570 claims are above the specialty average of 847.
Nearby Hematology & Oncology Physician Providers in Illinois
Other clinicians with the same primary specialty enrolled in Illinois, drawn from the same CMS NPPES roster as Cao.
Compare Hematology & Oncology Physician nationally: see state-by-state distribution →
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the Illinois medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Hematology & Oncology Physician peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
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Frequently Asked Questions
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Data Sources
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Prescribing Data
- CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology