GammaPod™: Stereotactic Radiotherapy for Breast Cancer

  A new option for noninvasive, precision SBRT in one to five fractions

The GammaPod is an optimized solution for ultra-accelerated stereotactic partial breast irradiation in the prone position. The technology has been designed to overcome the challenges of current techniques, improve the treatment experience for patients and increase capacity and patient throughput for cancer centers. Radiotherapy for localized breast cancer in Germany (and around the world) is moving toward shorter courses of radiation and partial breast treatments. The GammaPod is designed to deliver noninvasive highly conformal dose distributions with sharp fall off that maximize the dose to the target and limit dose to surrounding healthy breast tissue, the heart and lungs.

The GammaPod Opportunity

For appropriately selected patients, radiation oncologists can use the GammaPod to:

  • Reduce twice-daily accelerated partial breast irradiation (APBI) to between one and five noninvasive fractions of SBRT
  • Deliver preoperative SBRT in one or several sessions to irradiate smaller target volumes than adjuvant radiotherapy
  • Replace multi-fraction tumor bed boosts with a single noninvasive treatment for whole breast irradiation (WBI) patients

System Overview

GammaPod™: Stereotactic Radiotherapy

The GammaPod irradiation unit sits beneath the treatment couch, so patients are set up in the prone position above the sources for treatment delivery.

Delivery from Thousands of Beam Angles
During treatment, 25 Cobalt-60 sources continuously rotate to deliver the prescribed dose from thousands of beam angles. The individual beams converge to create an intense focal spot, delivering the full dose to the target while sparing surrounding healthy tissue.

Dynamic Dose Painting
To create exceptionally conformal dose distributions with sharp falloff, the treatment couch moves during treatment to dynamically paint the dose as the focal spot moves across the target in three dimensions.
Dynamically Changing 25 mm and 15 mm Collimators
Two collimator sizes, 25mm and 15mm, are used to shape the beams during treatment. The GammaPod automatically switches between collimators with no user intervention required.

GammaPod™: Stereotactic Radiotherapy
GammaPod™: Stereotactic Radiotherapy

Breast Cup System for Immobilization and Stereotactic Localization

Stereotactic radiotherapy requires high degrees of precision and accuracy. The GammaPod uses a first of its kind vacuum-assisted, dual-cup system that adheres noninvasively to the breast. The GammaPod breast cup system provides breast tissue immobilization, serves as a stereotactic frame and enables reproducible setup between imaging and treatment.

Patients are custom fit with the appropriately sized inner cup. There are 26 sizes available. A silicone flange is used to join the inner cup to the outer cup, which contains an embedded stereotactic fiducial wire. The breast cup is noninvasively applied to the patient and held in place with adhesive that is removed after treatment. When a suction pump is attached to breast cup and activated, air is removed from between the cups to conform the breast tissue to the shape of the inner cup and improve the stability of the immobilization.

Prone Patient Positioning

Treating patients in the prone position naturally pulls the target away from the heart, left anterior descending artery (LAD) and lungs for improved dose sparing. Prone setup has also been proven to minimize the effect of breathing motion.

To optimize the setup process during imaging and treatment, the GammaPod system includes a patient loading system in each room. The patient steps onto the loader wearing the breast cup, which fits through an aperture and is docked to the patient couch. The loaders gently rotate the patient and couch from the standing to prone position.

GammaPod™: Stereotactic Radiotherapy
GammaPod™: Stereotactic Radiotherapy

Same Day Imaging and Treatment with Rapid Online Treatment Planning

The GammaPod treatment planning system (TPS) uses sophisticated Monte Carlo dose calculations, the gold standard in radiotherapy, to create a dynamic travel path on which the couch will move during treatment to deliver the prescribed dose. To accommodate the scan-plan-treat clinical workflow, the TPS provides clinicians with tools for quickly creating a new treatment plan each day based on changes to the target and anatomy. The resulting plans are highly conformal with sharp falloff.

GammaPod ™ is for investigational use only and cannot be marketed or put into service until it has been made to comply with the Medical Device Directive (93/42/EEC). The device has received FDA 510(k) clearance.

1 Formenti, S. C., DeWyngaert, J. K., Jozsef, G., & Goldberg, J. D. (2012). Prone vs Supine Positioning for Breast Cancer Radiotherapy. JAMA, 308(9), 861–863.