Breast cancer is the most common cancer in women besides skin cancer. Breast cancer accounted for 27% of all new cancer cases in women in the U.S. in 2009 and was the second leading cause of cancer deaths after lung cancer.
Breast cancer that is caught early is known as early-stage breast cancer. For patients diagnosed with early-stage breast cancer, removal of part of the breast (lumpectomy) followed by radiation therapy to the breast results in the same cure rates as surgical removal of the whole breast (modified radical mastectomy).
With the decades old approach to radiation therapy, the whole breast is irradiated following a lumpectomy. Accelerated partial breast irradiation (APBI) is a relatively new form of radiation treatment for early-stage cancer. APBI involves the temporary placement of a radioactive source inside of the lumpectomy cavity. Only breast tissue within 1.0 cm (0.4 inch) of the lumpectomy cavity is treated with APBI, not the whole breast. A surgeon places an APBI catheter inside of the lumpectomy cavity in his or her office one to three weeks after performing a lumpectomy and sentinel lymph node biopsy. A radioactive source is subsequently passed through a catheter twice each day for a total of 10 outpatient treatments over 5-7 days. Each radiation treatment takes only 15 minutes. No radiation is left behind in the patient. Although breast cancer patients treated with APBI 5 years ago have typically done as well as patients treated with whole breast irradiation, whole breast irradiation remains the gold standard pending an additional 5 years of follow up.
One advantage of APBI over whole breast irradiation is that the radiotherapy is delivered over only one week rather than 5-7 weeks. Another advantage of APBI is that the volumes of heart and lung irradiated to clinically significant levels are lower than with whole breast irradiation. In addition, the appearance of the breast after APBI compares favorably with the appearance after whole breast irradiation.
Patients may be considered for APBI outside the setting of a clinical study if they are 50 years of age or older and their breast cancer is less than or equal to 3.0 cm (1.2 inches) and is estrogen and progesterone receptor positive. In addition, none of the lymph nodes in the armpit, known as the axillary nodes, should be involved.
An advantage of the SAVITM (Strut-Adjusted Volume Implant) catheter is that one can contour the radiation so as to avoid a radiation hot spot in the skin or ribs.
Click the link below to go to the manufacturer's (Cianna Medical, Inc., Aliso Viejo, CA) website.