Select Page

Precision targeting

at your fingertips.

TheraMarkTM is only distributed in the USA.

Non-Palpable Breast Tumor Localization

Wire-free, small and precise.
A simpler method for patients, radiologist and surgeons, alike.

We understand that your clinical time is invaluable and your patient care is priority. In fact, the patient experience is deeply intertwined with the prescribed care delivered.

Traditional breast wire localization techniques involve careful positioning of wires, patient transport and interdepartmental scheduling challenges, all of which add time, further complexity and take away from the patient experience.

But what if there were an easier, patient-focused way to improve localization and reduce procedure time?

TheraMarkTM can help with just that.

flexible simplicity

Radio-guided surgery is a staple for breast surgeons therefore the surgical technique is natural and intuitive with a highly flexible approach to localization.

Patient Focused

RSL operating times are shorter with less technical difficulty for the surgeon. Furthermore, high patient satisfaction rates provide incentive for surgeons to strongly consider RSL as an alternative to wire localization.1,2  

Precise localization

Radiation seed localization (RSL) provides:
(1) A point source of consistent gamma activity to guide the surgeon.

(2) Precise tumor localization for the surgeon and radiologist. 

Process Efficiency

RSL eliminates the interdepartmental scheduling challenge of traditional wire localization techniques. RSL can be performed time independent of surgery. Patients need not wait in the hospital between procedures.

Product Offerings

TheraMarkTM is a sterile, single use device composed of a low activity Iodine-125 seed intended for temporary interstitial implantation to localize target tissue for excision. As a point source of consistent gamma activity, TheraMarkTM precisely localizes the target tissue, resulting in operating times that are shorter with less technical difficulty for the surgeon. This procedure efficiency paired with high patient satisfaction provide incentive for surgeons to strongly consider RSL as an alternative to wire localization.1,2

The TheraMarkTM delivery system consists of a stainless steel 18-gauge needle available in lengths of 5, 7, or 12cm.


3 product configurations available: loose seed, encased seed and braided suture.


18-gauge needle available in lengths of 5, 7 or 12cm for each product configuration.


Each configuration is sold in a uniform (non-mixed) pack of 5.

Loose Seed

AgX100® I-125, loose seed at 0.8mm diameter by 4.5mm length.

Encased Seed

AgX100® I-125 seed encased in a bioabsorbable polydioxanone polymer (AnchorSeed®) designed to improve seed fixity in tissue.

Braided Suture

AgX100® I-125 seed embedded in a polyglactin-910 braided suture designed to improve seed fixity in tissue.

Theragenics Brachytherapy

Options that matter from your trusted industry partner.

At Theragenics, we are committed to developing, sourcing and providing targeted radiation solutions for the treatment of cancer. For over 40 years, we have been your trusted industry partner advancing brachytherapy treatment globally.

The introduction of TheraMarkTM is an extension of our continued devotion to improving patient lives and transforming healthcare experiences.

Contact us today to add an efficient, patient-focused approach to your localization needs.

Theragenics Brachytherapy

We deliver innovative solutions to improve patient outcomes with every order we fill.

Visit for more brachytherapy information. 

1. Lovrics PJ, Goldsmith CH, Hodgson N et al. A multicentered, randomized, controlled trial comparing radioguided seed localization to standard wire localization for nonpalpable, invasive and in situ breast carcinomas. Ann Surg Oncology 2011; 18: 3407-14.

2. Bloomquist EV, Ajkay N, Patil S et al. A Randomized Prospective Comparison of Patient-Assessed Satisfaction and Clinical Outcomes with Radioactive Seed Localization versus Wire Localization.
Breast J 2016; 22: 151-7.

Theragenics, AgX100, and TheraMark are trademarks of Theragenics Corporation. ©2022 Theragenics Corporation.