Welcome to Duluth

We are thankful you have chosen our practice as your trusted resource for oncology or hematology care. Our Duluth office is conveniently located near Gwinnett Place Mall to conveniently serve all of our central north Gwinnett patients.

Our Duluth office is partnered with the Duluth Gwinnett Medical 3620 Howell Ferry Rd in Duluth. We can be found in the Physicians Building on the 4th floor.

Helpful office information:

Physicians: Duluth is served by 2 primary physicians- 

Dr. Chris Hagenstad

Dr. I-Wan Chang

Nurse Practitioners:

Barbara O'Callaghan

Nan Park

Office hours: The office is open from 7:30 am to 5:00 pm, phone lines open at 8:30 am. Nurses are available from 8:30 am until 5:00 pm. Physician appointments are from 9:00 am until 4:00 pm. Our main office line is 770-623-6433.

Nurse Line:  Each office has as nurse line that you can call for any medical questions and concerns.  You will be prompted to leave a message for the nursing staff.  We have a nurse on call during business hours who checks the voicemail hourly and works closely with your physician to address your needs.  ALL calls will be returned by the end of the business day in the order of urgency. All messages left after 4:00 PM may not be returned until next business day. Our Duluth nurse line is (770) 623-6433 Ext. 3313.

After Hours: If you are in need of medical advice after our office is closed, please dial our main number (770-623-6433) and our 'after hours' service will answer. They in turn will take your message and contact the physician on call for that day. You must disable your caller id block in order for the doctor to return your call. Please be aware that after hour calls may not be returned by the physician that you normally see in our office.

Directions to Our Office

From Atlanta:

  • Take I-85 North to Pleasant Hill Road (Exit 104)

  • Turn left and go about 8 miles

  • Northside Hospital Duluth is on your left

  • We are in Suite 480

Keep up with our latest events and patient-offered activities on our Monthly Calendar!

Take advantage of everything our Northside Hospital Cancer Institute has to offer here.

If you or a loved one finds that you need help with either oncology related or hematology needs, we are here for you every step of the way. From our patient coordinators to our medical staff, our employees are expertly trained to focus 100% on your needs. Please reach out to us with any questions you may have, or call our main office at 770-623-6433. We are your resource for Cancer Care.



Phone: (770) 623-6433

Fax: (770) 623-6416

Nurse: (770) 623-6433 Option 2

Phone lines open at 8:30



Monday - Friday 7:30 - 5:00

3855 Pleasant Hill Road
Suite 480
Duluth, GA 30096




Please do not use this contact form for sensitive medical questions, lab results or emergencies. For emergencies, please dial 911 immediately for assistance. Please allow up to 24 hours for response time.

Thank you for your help and understanding!

Now Serving 4 Gwinnett Locations:

631 Professional Drive
Suite 450
Lawrenceville, GA 30046
Phone: (770) 963-8030


3855 Pleasant Hill Road
Suite 480
Duluth, GA 30096
Phone: (770) 623-6433


1700 Tree Lane
Suite 490
Snellville, GA 30078
Phone: (770) 979-2828



2098 Teron Trace

Suites 400-500

Dacula, GA 30019

Phone: (678) 722-3940