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

Dr. Rena Desai Callahan, MD

Individual provider Hematology (Internal Medicine) Physician · NPI 1487856779

Dr. Rena Desai Callahan, MD is a Hematology/Oncology in Valencia, California. Graduated from Perelman School of Med at the University of Pennsylvania in 2004, 22 years ago. Practices with The Regents of the University of California, a 1,414-clinician group, works from 3 locations, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
22
Trained at
Perelman School of Med at the University of Pennsylvania
Licensed in
CA
In the registry since
2007
Specialties on file
4
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

27235 Tourney Rd Ste 2400
Valencia, CA 91355-5905
Phone: (661) 255-5350
Fax: (661) 255-9907
Show map & directions

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

Additional practice locations (2)

  • 2336 Santa Monica Blvd Ste 315, Santa Monica, CA 90404-2095 — (310) 829-5471
  • 2020 Santa Monica Blvd Ste 230, Santa Monica, CA 90404-2124 — (310) 829-5471

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence A94238 (CA)
Hematology (Internal Medicine) Physician Taxonomy 207RH0000X · Licence A94238 (CA)
Medical Oncology Physician Taxonomy 207RX0202X · Licence A94238 (CA)
Surgical Oncology Physician Taxonomy 2086X0206X · Licence A94238 (CA)

Record details

NPI number1487856779
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedMay 31, 2007
Last updated in NPPESJanuary 23, 2020
Certification dateJanuary 23, 2020

Medicare enrollment

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

Medicare specialtyHEMATOLOGY/ONCOLOGY
Also practisesINTERNAL MEDICINE, SURGICAL ONCOLOGY
Medical schoolPERELMAN SCHOOL OF MED AT THE UNIVERSITY OF PENNSYLVANIA
Graduated 2004 (22 years in practice)
Group practice The Regents Of The University Of California — 1414 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations6 on file with Medicare