Quick answers
- Which hospitals does Marissa D. Rybstein work at?
- Medicare's official clinician data lists Marissa D. Rybstein at 2 hospitals: Long Island Community Hospital and NYU Langone Hospitals. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Marissa D. Rybstein see patients?
- Medicare's clinician data lists 1 practice location in Mineola, NY. Call before your visit to confirm the address.
- What is Marissa D. Rybstein's specialty?
- Medicare lists Hematology/Oncology as the primary specialty.
- Does Marissa D. Rybstein accept Medicare assignment?
- Yes. Medicare's clinician data says Marissa D. Rybstein 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 Marissa D. Rybstein offer telehealth?
- Medicare's clinician data says Marissa D. Rybstein offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for Marissa D. Rybstein?
- (516) 663-9500, as listed in official Medicare / NPI Registry data.
- What is Marissa D. Rybstein's NPI number?
- 1447593132. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Marissa D. Rybstein works
Medicare's Facility Affiliation Data lists Marissa D. Rybstein at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Long Island Community HospitalPatchogue, NY · Acute Care Hospital · CCN 330141
- NYU Langone HospitalsNew York, NY · Acute Care Hospital · CCN 330214
Practice locations
Addresses where Marissa D. Rybstein is enrolled with Medicare (CMS data updated 2026-10-02).
- 120 Mineola Blvd, Suite 500Mineola, NY 11501 (516) 663‑9500
Group practices
Medicare enrollment lists Marissa D. Rybstein as a member of this group (CMS data updated 2026-10-02).
- New York University6,134 clinicians in the group
Specialties
- Hematology/Oncologyprimary
Other hematologist-oncologists in New York
Clinicians with the same Medicare primary specialty in New York — not a recommendation.
Clinician information
| Medical school | New York Medical College |
|---|---|
| Graduation year | 2013 |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1447593132 |
| 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