Doctor profile · Federal record

Dr. Thorvardur Halfdanarson, M.D.

Medical Oncology Physician (CMS: Medical Oncology) · Internal Medicine Physician · Internal Medicine Physician · Hematology & Oncology Physician · Hematology & Oncology Physician · Hematology & Oncology Physician · Rochester, MN

  • NPI 1083684187
  • Accepts Medicare
  • 31 yrs in practice
  • Licensed in 3 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 2 locations .

NPPES Updated May 11, 2026
Primary practice
200 1St St Sw
Rochester, MN 559050001
(507) 284-2511
Additional location
13400 E Shea Blvd
Scottsdale, AZ 852595452
(480) 301-8000

Credentials & registration

NPPES · NUCC
NPI registered
January 2006 — 20 yrs on file
Profile last updated
August 14, 2020
Year of graduation
1995 — 31 yrs since
Specialty taxonomy
207RX0202X — NUCC code
State licenses (3)
Minnesota #45995 · Iowa #37199 · Arizona #46666

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1083684187. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
27,738
Distinct HCPCS
10
Medicare allowed
$638,260
HCPCS Description Services Patients Avg allowed
J9271 Injection, pembrolizumab, 1 mg 6,700 26 $45
J1453 Injection, fosaprepitant, 1 mg 6,300 37 $0
J9267 Injection, paclitaxel, 1 mg 4,752 22 $0
J9144 Injection, daratumumab, 10 mg and hyaluronidase-fihj 3,781 20 $48
Q5119 Injection, rituximab-pvvr, biosimilar, (ruxience), 10 mg 1,210 16 $28
J2405 Injection, ondansetron hydrochloride, per 1 mg 1,048 81 $0
J1100 Injection, dexamethasone sodium phosphate, 1 mg 954 75 $0
J9041 Injection, bortezomib, 0.1 mg 615 16 $5
J2469 Injection, palonosetron hcl, 25 mcg 340 29 $1
96375 Injection of additional new drug or substance into vein 244 111 $16

In context: peer comparison

Among 30 peers in Rochester Medical Oncology Physician, average services per provider: 717. This provider delivers 39× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$17,812
Transactions
19
Manufacturers
5
Payer (manufacturer) Industry Txns Amount
Exelixis INC. 15 $14,496.02
Boehringer Ingelheim Pharmaceuticals, INC. 1 $2,960.00
Curium US LLC 1 $143.71
TerSera Therapeutics LLC 1 $140.25
AstraZeneca Pharmaceuticals Lp 1 $72.00

By nature of payment

Honoraria
$10,230
Consulting Fee
$5,600
Travel and Lodging
$1,221
Food and Beverage
$761

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
43
Patients
0
Total drug cost
$17,126
Drug Type Claims Patients Total cost
Colestipol Hcl Generic 18 0 $2,432
Eliquis (Apixaban) Brand 14 0 $14,551
Ondansetron Hcl Generic 11 0 $143

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Thorvardur Halfdanarson's medical specialty?
Dr. Thorvardur Halfdanarson practices Medical Oncology Physician in Rochester, MN.
Where does Dr. Thorvardur Halfdanarson practice?
Dr. Thorvardur Halfdanarson practices at 200 1St St Sw, Rochester, MN 559050001. Office phone: 5072842511.
What is Dr. Thorvardur Halfdanarson's NPI?
Dr. Thorvardur Halfdanarson's National Provider Identifier (NPI) is 1083684187, issued by NPPES.
Does Dr. Thorvardur Halfdanarson accept Medicare assignment?
Yes. Dr. Thorvardur Halfdanarson accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Thorvardur Halfdanarson commonly perform?
Top Medicare-reported procedures in 2023: Injection, pembrolizumab, 1 mg (HCPCS J9271); Injection, fosaprepitant, 1 mg (HCPCS J1453); Injection, paclitaxel, 1 mg (HCPCS J9267). Source: CMS Medicare Physician & Other Practitioners file.