Use of the Contura™ Catheter in Intermediate-Risk, Pathological Stage 0, I, or II (Up to 3.0 cm) Breast Cancer Patients
|Study Design:||Endpoint Classification: Safety/Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||Registry Study of the Contura™ Multi-Lumen Balloon (MLB) Applicator for Accelerated Partial Breast Irradiation in Intermediate-Risk, Pathological Stage 0, I, or II (Up to 3.0 cm) Breast Cancer Patients|
- Maximum skin dose is less than or equal to 100% of the prescribed radiation dose and air/fluid pocket next to the balloon is less than or equal to 3.0% of the planning target volume for plan evaluation [ Time Frame: 19 months ] [ Designated as safety issue: Yes ]
- Number of cases where the balloon catheter has to be explanted when the balloon-to-skin spacing is only 3-6 mm. [ Time Frame: 19 months ] [ Designated as safety issue: Yes ]
|Study Start Date:||October 2007|
|Study Completion Date:||December 2009|
|Primary Completion Date:||December 2009 (Final data collection date for primary outcome measure)|
A Contura balloon catheter is placed in the lumpectomy cavity. Later that morning, accelerated partial irradiation begins.
Device: Contura catheter
Radiation therapy is delivered to a total dose of 34 Gy in 10 fractions bid over 5-7 days. Each day, the high dose rate iridium-192 brachytherapy treatments are separated by 6 hours. Each radiation treatment takes 15-30 minutes.
Other Name: Contura Multi-Lumen Balloon Applicator
In approximately 20% of patients who are considered for accelerated partial breast irradiation (APBI), the balloon-to-skin distance ranges from 3-6 mm. The Contura applicator has 5 source lumens. In contrast, the MammoSite catheter has a single source lumen. The ability to choose from multiple source lumens with the Contura catheter allows one to avoid a radiation "hot spot" in the skin in cases where the balloon-to-skin spacing is only 3-6 mm.
Another limitation of the MammoSite catheter is that one cannot improve on the suboptimal conformance of the balloon with the surrounding breast tissue. An air/fluid pocket next to the balloon can push breast tissue at greatest risk of harboring residual disease away from the radioactive source. With APBI, the planning target volume for plan evaluation (PTV_EVAL) is defined as the breast tissue volume bounded by uniform expansion of the balloon radius in all dimensions by 10 mm less the balloon volume. PTV_EVAL is limited to 5 mm from the skin surface and by the posterior breast tissue extent (chest wall and pectoralis muscles are excluded). The volume of an air/fluid pocket is usually 4.8% ± 1.1% (mean ± standard error) of PTV_EVAL. The Contura applicator has a vacuum lumen with 2 openings adjacent to the balloon that allow for air/fluid removal. By using the vacuum lumen on a Contura applicator, one can typically decrease the size of an air/fluid pocket by about one third. In approximately 90% of Contura patients, the volume of an air/fluid pocket around the balloon can be reduced to less than or equal to 3.0% of PTV_EVAL. In contrast, the volume of an air/fluid pocket around the balloon is less than or equal to 3.0% of PTV_EVAL in only about half of MammoSite patients. Since this study addresses intermediate-risk patients, it is particularly important that the size of an air/fluid pocket be minimized with a Contura applicator.
SenoRx, Inc. (Aliso Viejo, CA) is currently conducting a registry study of the Contura MLB applicator in the "low-risk" patient population. This "intermediate-risk" study is complimentary to the low-risk registry study. There is no overlap in patient eligibility. Intermediate-risk patients meet any of the following criteria:
- Age 18-49 years, or
- Estrogen receptor-negative and progesterone receptor-negative breast cancer, or
- 1-3 involved axillary lymph nodes
Please refer to this study by its ClinicalTrials.gov identifier: NCT00882089
|United States, California|
|Cancer Center of Irvine|
|Irvine, California, United States, 92618|
|Principal Investigator:||Richard B Wilder, MD||Cancer Center of Irvine|
|Study Chair:||Kenneth M Tokita, MD||Cancer Center of Irvine|