DR. IVAN STEPHEN LOWENTHAL M.D.
NPI 1043245889
Internal Medicine - Medical Oncology in Tamuning, GU

Q: What is Ivan Lowenthal's NPI number?

The NPI number for Ivan Lowenthal is 1043245889. It was assigned to this individual provider in the NPPES registry on July 11, 2006.

Q: What is Ivan Lowenthal's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Medical Oncology, with taxonomy code 207RX0202X.

Q: When was this NPI record last updated?

The NPPES record for Ivan Lowenthal was last updated on March 19, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since July 11, 2006PECOS Enrolled

633 GOV CARLOS CAMACHO RD., STE B5, TAMUNING, GU 96913(671) 647-4656(671) 647-4660 Get Directions Write a Review

NPPES record last updated: March 19, 2025. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Mar 19, 2025, Mar 7, 2023, Oct 29, 2018 and 1 more (4 updates tracked since 2016).

On this page

About Dr. Ivan Stephen Lowenthal M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. IVAN STEPHEN LOWENTHAL M.D. (NPI 1043245889) is an individual medical oncology provider in Tamuning, Guam, licensed in Guam (M-1925) and active in the NPI registry since July 2006. He is enrolled in Medicare PECOS and maintains 2 additional practice locations.

NPPES Registry Identity

NPI1043245889

Entity TypeIndividualMale

Primary Taxonomy207RX0202X

Provider Legal NameDR. IVAN STEPHEN LOWENTHALCredential: M.D.

Location Address633 GOV CARLOS CAMACHO RD., STE B5Tamuning, GU 96913-3194

Mailing Address633 Gov Carlos Camacho Rd., Ste B5Tamuning, GU 96913-3194 · (671) 647-4656 · Fax (671) 647-4660

Phone(671) 647-4656

Fax(671) 647-4660

Sole ProprietorYes

Enumeration DateJuly 11, 2006

Last NPPES UpdateMarch 19, 20254 updates tracked since enumeration

NPPES CertifiedMarch 17, 2025

✔ NPI 1043245889 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Medical OncologyAllopathic & Osteopathic Physicians

Taxonomy Code207RX0202X

Licenses✔ Licensed in GU · M-1925✔ Licensed in CT · 18789

Definition

An internist who specializes in the diagnosis and treatment of all types of cancer and other benign and malignant tumors. This specialist decides on and administers therapy for these malignancies as well as consults with surgeons and radiotherapists on other treatments for cancer.

Secondary Practice Locations 2

Location 1385 Huron AveCambridge, MA 02138-6820 · Phone (860) 307-3393

Location 26 Devine St Ste 2CNorth Haven, CT 06473-2222 · Phone (203) 407-8002

Other Identifiers 5

Medicaid001187897CT

Other18789CT · Ct. License

OtherM-1925GU · Guam License

Other06-1088532Tax Id #

Other1683CT · Ct Controlled Substance

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Ivan Stephen Lowenthal M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

Medicare enrollment records show Ivan Lowenthal reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Beth Israel Lahey Health Specialty Care, Inc.

Internal Medicine

298 WASHINGTON ST
Gloucester, MA 01930

Reassigned Medicare billing, Massachusetts enrollment
477 clinicians in this Medicare group

NPI 1235147760 (978) 282-3681

Yale New Haven Hospital

General Acute Care Hospital

20 YORK ST
New Haven, CT 06504

Reassigned Medicare billing, Connecticut enrollment
130 clinicians in this Medicare group

NPI 1336139500 (203) 688-2046

Yale University

Advanced Practice Midwife

100 CHURCH ST S STE 200, YALE SCHOOL OF NURSING
New Haven, CT 06519

Reassigned Medicare billing, Connecticut enrollment
3,728 clinicians in this Medicare group

NPI 1124148887 (203) 737-5432

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 96913 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$180.05 typical visit price

range $60.53 – $180.05

Typical copayment $45.01 (range $15.13 – $45.01)

Most-billed visit code 99205

Established Patient

$105.65 typical visit price

range $20.09 – $147.56

Typical copayment $26.41 (range $5.02 – $36.89)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Ivan Lowenthal's NPI number?

The NPI number for Ivan Lowenthal is 1043245889. It was assigned to this individual provider in the NPPES registry on July 11, 2006.

Where is Ivan Lowenthal located?

Ivan Lowenthal practices at 633 Gov Carlos Camacho Rd., Ste B5, Tamuning, GU 96913. The listed phone number is (671) 647-4656.

What is Ivan Lowenthal's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Medical Oncology, with taxonomy code 207RX0202X.

Is Ivan Lowenthal enrolled in Medicare?

Yes. Ivan Lowenthal is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Ivan Lowenthal's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Ivan Lowenthal reassigns Medicare benefits to 3 organizations: Beth Israel Lahey Health Specialty Care, Inc. (Gloucester, MA), Yale New Haven Hospital (New Haven, CT) and Yale University (New Haven, CT). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Ivan Lowenthal's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Ivan Lowenthal was last updated on March 19, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.