Quick answers
- Which hospitals does Steven Gruenstein work at?
- Medicare's official clinician data lists Steven Gruenstein at 1 hospital: Lenox Hill Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Steven Gruenstein see patients?
- Medicare's clinician data lists 2 practice locations, including New York, NY. Call before your visit to confirm the address.
- What is Steven Gruenstein's specialty?
- Medicare lists Hematology/Oncology as the primary specialty.
- Does Steven Gruenstein accept Medicare assignment?
- Yes. Medicare's clinician data says Steven Gruenstein accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- Does Steven Gruenstein offer telehealth?
- Medicare's clinician data says Steven Gruenstein offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for Steven Gruenstein?
- (631) 751-3000, as listed in official Medicare / NPI Registry data.
- What is Steven Gruenstein's NPI number?
- 1407855307. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Steven Gruenstein works
Medicare's Facility Affiliation Data lists Steven Gruenstein at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Lenox Hill HospitalNew York, NY · Acute Care Hospital · CCN 330119
Practice locations
Addresses where Steven Gruenstein is enrolled with Medicare (CMS data updated 2026-10-02).
- 12 E 86th St, Ofc 4cNew York, NY 10028 (631) 751‑3000
- 1421 3rd AveNew York, NY 10028 (631) 751‑3000
Group practices
Medicare enrollment lists Steven Gruenstein as a member of this group (CMS data updated 2026-10-02).
- North Shore Hematology Oncology Associates PC479 clinicians in the group
Specialties
- Hematology/Oncologyprimary
Other hematologist-oncologists in New York
Clinicians with the same Medicare primary specialty in New York, NY — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1984 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1407855307 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians