npidata.org Sign in
Products
Provider RadarWatch an area and specialty — weekly alerts on new cliniciansPractice RadarWeekly alerts when new organisations register nearbySpecialtiesEvery NUCC taxonomy, with counts by state and cityStatesProvider counts and breakdowns for all 50 statesPhysician listsMDs and DOs with addresses and phone numbersNP listsNurse practitioners, the fastest-growing groupAPIJSON, delta feed, free tier
Use cases
Healthcare sales prospectingPhysician recruiting and locum staffingMedical device sales territory planningCredentialing and provider verificationHealthcare marketing lists and audience buildingPharmaceutical sales and prescriber targeting
Account
Start freeThree radars and an export a month Sign in Pricing
Explore
Data Labs API
About
About usTermsPrivacyContact us

Search › Massachusetts › Hematology & Oncology Physician

Jaroslaw Jac, MD

NPI 1326029802 · on the registry since 2005

Practice

Address
150 Flanders Rd
Westborough, MA 01581
Phone
(508) 870-2222
Organisation at this address
Metro West Rehab Corp
Metro West Rehab Corp
Metro West Rehab Corp
Metro West Rehab Corp
Whittier Rehabilitation Hospital
Inferred from a shared address, not stated in the registry.
Clinicians at this address
12

Additional practice sites

  • 3073 White Mountain Hwy, North Conway, NH
  • 580 Court St, Keene, NH

Registry record

Primary taxonomy
Hematology & Oncology Physician
207RH0003X
Also registered as
Internal Medicine Physician
Hematology & Oncology Physician
Internal Medicine Physician
Hematology & Oncology Physician
Hematology & Oncology Physician
Licence states on file
MA, NH, TX, ME
From the registry's licence fields, which are often incomplete.
Sex
Male
Record last updated
2026-07-24

Source: CMS National Plan and Provider Enumeration System. Registration is not the same as practising, and the registry records no retirement — some people listed here no longer practise. More in Massachusetts