Quick answers
- Which hospitals does Marisa Siebel work at?
- Medicare's official clinician data lists Marisa Siebel at 4 hospitals: Long Island Jewish Medical Center, North Shore University Hospital, Ns/Lij HS Huntington Hospital and Ns/Lij HS Southside Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Marisa Siebel see patients?
- Medicare's clinician data lists 7 practice locations, including Huntington, NY, Greenlawn, NY and New Hyde Park, NY. Call before your visit to confirm the address.
- What is Marisa Siebel's specialty?
- Medicare lists Medical Oncology as the primary specialty, and also Hematology/Oncology.
- Does Marisa Siebel accept Medicare assignment?
- Yes. Medicare's clinician data says Marisa Siebel 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 Marisa Siebel offer telehealth?
- Medicare's clinician data says Marisa Siebel offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for Marisa Siebel?
- (631) 427-6060, as listed in official Medicare / NPI Registry data.
- What is Marisa Siebel's NPI number?
- 1942303094. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Marisa Siebel works
Medicare's Facility Affiliation Data lists Marisa Siebel at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Long Island Jewish Medical CenterNew Hyde Park, NY · Acute Care Hospital · CCN 330195
- North Shore University HospitalManhasset, NY · Acute Care Hospital · CCN 330106
- Ns/Lij HS Huntington HospitalHuntington, NY · Acute Care Hospital · CCN 330045
- Ns/Lij HS Southside HospitalBay Shore, NY · Acute Care Hospital · CCN 330043
Practice locations
Addresses where Marisa Siebel is enrolled with Medicare (CMS data updated 2026-10-02). The first 5 of 7; the Medicare profile lists all.
- 270 Park AveHuntington, NY 11743 (631) 427‑6060
- 270 Pulaski RdGreenlawn, NY 11740 (631) 549‑4858
- 270 Pulaski Rd, Suite DGreenlawn, NY 11740 (631) 427‑8060
- 27005 75th AveNew Hyde Park, NY 11040 (718) 470‑4449
- 301 E Main StBay Shore, NY 11706 (516) 734‑8656
Group practices
Medicare enrollment lists Marisa Siebel as a member of this group (CMS data updated 2026-10-02).
- North Shore Health System Medical Faculty Group Practice Inc164 clinicians in the group
Specialties
- Medical Oncologyprimary
- Hematology/Oncologyalso
Other oncologists in New York
Clinicians with the same Medicare primary specialty in New York — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2000 |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1942303094 |
| 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