Brian D. Lawenda, M.D.
Medical Director and Radiation Oncologist, GenesisCare USA, Kennewick, WA
Introduction: Elevating Precision in Post-Lumpectomy Radiation Therapy
In radiation oncology, the precision of post-lumpectomy radiation therapy is critical. The advent of VeraForm®, an FDA 510(k) cleared radiopaque tissue marker, has marked a significant advancement in this area. VeraForm’s primary utility lies in its ability to enable precise targeting of the tumor bed, a vital aspect of effective radiation therapy. This precision is not just about enhancing the efficacy of treatment; it's also crucial in minimizing the exposure and potential harm to surrounding healthy tissue.
In my role as a community-based radiation oncologist managing a moderate number of breast cancer cases, I've formed a strong partnership with local breast surgeons for the co-management of these patients. Over the years, we've evaluated numerous lumpectomy cavity markers and unanimously chose VeraForm for all our procedures. VeraForm stands out for its seamless integration into surgical workflows, superior accuracy, and patient comfort. Its radiographic visibility on CT scans has increased my confidence in accurately contouring the lumpectomy cavity. As a result, I've been able to reduce the expansion margins compared to when surgical clips were used, leading to less radiation of normal tissue in both boost and accelerated partial breast irradiation (APBI) treatments. Moreover, VeraForm's design allows for enhanced precision in image-guided radiation therapy (IGRT), due to its ease and speed of localization during treatment setup.
VeraForm is a radiopaque filament woven into the tumor bed during a lumpectomy procedure. Unlike traditional surgical clips which are placed around the periphery of the tumor bed, VeraForm is a flexible, adaptable marker that conforms to the shape and size of the tumor cavity. Additionally, VeraForm enables reapproximation and closure of the walls of the lumpectomy cavity, an approach geared toward reducing seroma accumulation. This adaptability allows for accurate and comprehensive marking of the tumor bed's boundaries.
VeraForm’s® Superior Delineation and Compatibility with Imaging Techniques
VeraForm’s conformable nature ensures an accurate delineation of the tumor bed. Since it is placed into the walls of the tumor bed, a 3-dimensional volume can be easily contoured on radiation therapy treatment planning software. Whereas with surgical clips, to similarly define the irregular contours of a tumor bed, an impractical number of clips would need to be placed to carefully and precisely delineate the walls of the cavity. Additionally, clips tend to migrate, which can lead to a less precise definition of the tumor bed's boundaries. Consequently, radiation oncologists often have to compensate for the lumpectomy cavity uncertainties by expanding the radiation margins, thereby increasing the volume of tissue exposed to radiation. By allowing for smaller, more accurately defined radiation volumes, VeraForm may play a pivotal role in reducing the risk of complications such as breast fibrosis and poor cosmetic outcomes by reducing the volume of normal breast tissue irradiated.
VeraForm’s superiority over surgical clips has been well-established in a recent peer-reviewed study[i], highlighting VeraForm’s ability to provide clear and accurate tumor bed (TB) delineation. In this comparative study involving 28 patients, VeraForm demonstrated significantly reduced interobserver variability in delineating the TB. Key findings included a 29.7% aggregate difference in volume between expert contours for VeraForm, compared to 55.4% for clip markers. Additionally, the dice coefficient, a measure of contour accuracy, was notably higher for VeraForm (0.54) compared to clip markers (0.44). These improvements were even more pronounced in complex oncoplastic reconstruction scenarios, where accurate TB delineation is crucial for effective radiation therapy. The study conclusively demonstrated VeraForm's ability to provide a more precise and consistent delineation of the TB, enhancing the precision of radiation therapy and potentially improving patient outcomes.
Significantly, VeraForm does not compromise the effectiveness of breast cancer surveillance imaging methods such as MRI, mammography, or ultrasound. Additionally, since VeraForm can be easily visualized with most x-ray-based image-guided radiation therapy (such as cone beam CT scan and Kv imaging) techniques, targeting the lumpectomy cavity can be more precise.
Navigating the Complexities of Oncoplastic Surgery
In the increasingly prevalent practice of oncoplastic surgery, where lumpectomy is combined with plastic surgery techniques for better cosmetic outcomes, accurately defining the tumor bed becomes more complex. Oncoplastic surgery can alter the shape and size of the breast, potentially moving the tumor bed, thereby creating challenges in targeting the area accurately for radiation therapy. VeraForm's adaptability and precision come to the fore in these scenarios, ensuring accurate radiation targeting even when the TB shifts out of the primary quadrant or undergoes significant shape changes. By addressing these complex surgical challenges, VeraForm significantly enhances the efficacy of post-surgical radiation therapy in oncoplastic cases[ii]
Encouraging Interdisciplinary Collaboration
Given the benefits of VeraForm, there is a compelling case for radiation oncologists to engage with surgical colleagues actively. Discussing the incorporation of VeraForm in the treatment planning process with surgeons can lead to more effective and patient-centered care. This interdisciplinary collaboration is crucial for optimizing treatment planning and execution, ensuring that surgical and post-surgical radiation therapy aspects are seamlessly integrated for the best patient outcomes.
Conclusion: A Strong Recommendation for VeraForm Integration
The integration of VeraForm in lumpectomy procedures represents a significant advancement in breast cancer treatment. Its ability to provide clear, consistent, and accurate delineation of the tumor bed is an important step forward in radiation therapy planning. It enhances treatment efficacy and plays a crucial role in safeguarding patient well-being. Radiation oncologists are encouraged to recognize the benefits of VeraForm and advocate for its integration in collaboration with surgeons to elevate the standard of care and outcomes for breast cancer patients.