Closing Office Letter

Closing Practice Letter

Due to Dr. Dennis Birenbaum’s declining health condition, THOC PA, Texas Hematology/Oncology Center will be closing their doors effective immediately.

It has been his honor and privilege to have been your oncology/hematology provider, some of you for many years. THOC is grateful for the opportunity to have served your medical needs, and wish everyone good health and happiness.

Dr. Wyszynski will be moving to Wellness & Care Group of Texas in Frisco. The contact number is 469-701-1770.
If you have an appointment already scheduled with us or need to make an appointment over the next several weeks, we encourage you to take one of the following steps:

● To contact Dr. Wyszynski at his new location;
● Speak with your primary care physician;
● Contact member services with your insurance carrier to find a new oncologist or hematologist

Health Records

Your health records from THOC will be transferred to Armstrong Archives LLC (the “Records Custodian”). The Records Custodian will continue to maintain your records in accordance with applicable confidentiality and security standards and with other applicable laws. Your records will be destroyed no less than six years after the last date of services you received from this Practice, although most records will be held for at least 10 years from the date of last service, depending upon applicable state and federal record retention requirements. 1 You may request your records or have your medical provider request them by calling 972-646-2031 or email

If you wish to have a copy of your records sent to you or to another provider or facility, you may submit a request to the Records Custodian:
Armstrong Archives: Medical Records 972-646-2031 or 972-242-7179

Please Note: In accordance with applicable state law, you may be charged for the copying and transmittal of the records. There may
be a short transition period until your records are barcoded and archived accordingly.

THOC PA dba Texas Hematology Oncology Center

For minors, the records will be held for six years beyond the date they reach 18 years of age.


If you have a question about billing, please email us at

If you are in need of lab work or pre-authorization information, please contact Dr. Wyszynski’s new location at 469-701-1770.

authorization letter