Skip to content

Specialties
Additional Services
Directory
- Centers & Clinics
- Physicians & Staff
More
Contact

Walshauser-ASCO-2026

Medical Oncology / Hematology

Justin D. Floyd, DO, FACOI
James L. Wade III, MD, FACP, FASCO, FACCC
Philip A. Dy, MD
Perry P. Guaglianone, MD, FACP
Mario R. Velasco Jr., MD, FACP
Hanna M. Saba, MD
Sebastien S. Kairouz, MD
Bassam N. Maalouf, MD
Mark A. Walshauser, MD, FACP, FASCO
Gibran H. Mahmud, MD
Evelena P. Ontiveros, MD, PhD
Bachir Farah, MD
Kristi M. Toennies, FNP, AOCNP
Christel G. Wheeler, DNP, FNP-BC
Michelle D. McQuillan, DNP, FNP-BC
Kelsey D. Beasley, FNP-C, AOCNP
Rachael E. DeMattei, DNP, FNP-BC
Rachel I. Kline, FNP-C
Sarah N. Mackey, FNP-C
Kaylee M. Beals, DNP, FNP-BC
Julianne J. Tomac, DNP, FNP-C
Shannon E. Niebrugge, FNP-C
Alexis J. Wernsman, FNP-C

Radiation Oncology

Edward C. Elliott, MD, FACR, FCAP
Mary Anne de Paz, MD
Renata C. Moore, MD
Seong R. Cho, MD
Harold A. Yoon, MD
Casey E. Duncan, MD
Jacob S. Witt, MD
Ryan C. Mueller, MD, BSRT(T)

Specialties

Medical Oncology
Hematology
Radiation Oncology
Research Studies & Clinical Trials
Pain Management
Patient & Family Education

Additional Services

Imaging Services
Infusion Services
Laboratory Services
Nursing
Oncology Care Model
Retail Pharmacy
Counseling
Patient Services
Patient Resource Guides
Office, Transcription & Billing
Prevention & Detection
Medicare

Centers & Clinics

Cancer Care Center of Decatur
Cancer Care Center of O’Fallon
Centralia Oncology Clinic
Crossroads Cancer Center (Effingham)
Anderson Hospital Warren Billhartz Cancer Center (Maryville)
Cancer Care Specialists of Illinois – Sparta
Carle Richland Memorial Hospital (Olney)
Clay County Hospital Medical Clinic (Flora)
DMH Cancer Care Institute (Decatur)
Fairfield Memorial Hospital – Medical Arts Complex
Sarah Bush Lincoln Fayette County Hospital (Vandalia)
HSHS Good Shepherd Hospital – Physicians Center (Shelbyville)
HSHS Holy Family Hospital (Greenville)
HSHS St. Elizabeth’s Radiation Oncology Center (O’Fallon)
HSHS St. Joseph’s Hospital – Breese Specialty Clinic
HSHS St. Joseph’s Hospital Highland – Medical Office Building
HSHS St. Mary’s Cancer Care Center (Decatur)
Kirby Medical Center (Monticello)
Memorial Hospital Oncology Clinic (Chester)
Pana Community Hospital Medical Mall
Salem Township Hospital
Sarah Bush Lincoln Regional Cancer Center (Mattoon)
Taylorville Memorial Hospital
Warner Hospital & Health Services (Clinton)

Recent News

Cancer Care Specialists of Illinois Welcomes Radwan H. Diab, MDAugust 1, 2026
A New Chapter in Cancer Care to Begin in the Warren Billhartz Cancer CenterJuly 22, 2026
Cancer Care Specialists of Illinois Welcomes Ryan C. Mueller, MD, BSRT(T)July 13, 2026
Cancer Care Specialists of Illinois Blood DriveJune 30, 2026
Cancer Care Specialists of Illinois, HSHS and Memorial Health Unite to Celebrate Cancer SurvivorsMay 28, 2026
Mark A. Walshauser, MD, FACP, FASCO Named Advocacy Champion by the Association for Clinical OncologyApril 21, 2026
Dr. Mario Velasco 1st in US to Enroll a Patient in Inavo123 StudyDecember 1, 2025
CCSI Receives Re-Certification for High-Quality Cancer Care from the Largest Oncology Association in United StatesNovember 21, 2025
Dr. Mark Walshauser Receives FASCO RecognitionNovember 10, 2025
Best Wishes, Dr. Estrada-Garcia!November 10, 2025
Exploring Blood Cancer Treatments and SupportOctober 20, 2025
CCSI Foundation – Support to Cancer and Hematology PatientsSeptember 18, 2025
KerbySTRONG – Saturday Aug. 9!August 7, 2025
National Cancer Survivors Day 2025May 12, 2025
Mark A. Walshauser, MD, FACP Named Advocacy Champion by the Association for Clinical OncologyApril 9, 2025

© Cancer Care Specialists of Illinois

All Rights Reserved

Specialties

Medical Oncology
Hematology
Radiation Oncology
Research Studies & Clinical Trials
Pain Management
Patient & Family Education

Additional Services

Imaging Services
Infusion Services
Laboratory Services
Nursing
Oncology Care Model
Retail Pharmacy
Counseling
Patient Services
Patient Resource Guides
Office, Transcription & Billing
Prevention & Detection
Medicare

More

MyChart
Certifications & Accreditations
CCSI News
CCSI Events Calendar
CCSI Foundation & CCSI Charitable Fund
Employment Opportunities
Our History
Privacy
Forms
Sitemap
Related Sites

Directory

Centers & Clinics
Physicians & Staff
Contact

Facebook
Twitter
YouTube
Instagram
LinkedIn