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

Ghassan Zalzaleh, MD

Individual provider Hematology & Oncology Physician · NPI 1992704035

Ghassan Zalzaleh, MD practises Internal Medicine in Oak Lawn, Illinois. Qualified in 1987, 39 years ago. Practices with Affiliated Oncologists LLC, a 42-clinician group and accepts Medicare assignment. Licensed in Illinois.

Years since qualifying
39
Licensed in
IL
In the registry since
2005
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

4400 W 95th St Ste 311
Oak Lawn, IL 60453-2654 Not confirmed with CMS for 11 years — call before visiting
Phone: (708) 424-9710
Fax: (708) 424-4331
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Hematology & Oncology Physician (primary) Taxonomy 207RH0003X · Licence 036089713 (IL)

Record details

NPI number1992704035
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJuly 20, 2005
Last updated in NPPESJuly 10, 2015

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Also practisesGENERAL PRACTICE
Medical schoolOTHER
Graduated 1987 (39 years in practice)
Group practice Affiliated Oncologists Llc — 42 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations4 on file with Medicare

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 patients679
Average patient age76

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 $4,555 202 payments · a meal or drink at a meeting or visit, not a fee
Consulting Fee $2,775 2 payments
Education $304 4 payments · educational material or training, 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. Those with a page here are linked.

Colleagues at Affiliated Oncologists LLC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 42 clinicians in the practice; 12 are shown here.

Other providers in Oak Lawn