Who Can Benefit From APBI & The Changing Treatment Landscape Joe L. Meadows, M.S. Medical Physicist The Lacks Cancer Center Saint Mary’s Health Care Grand Rapids, MI Joe Meadows M.S. St Mary’s March 2009 Joe Meadows M.S. St Mary’s March 2009
Overview of Partial Breast Irradiation (PBI) and patient selection criteria
Who can benefit from APBI
Review of patient selection criteria
Review of Techniques: Mammosite, Contura, Xoft, and 3D-EBRT PBI, and Single-fraction, intra-operative PBI
Joe Meadows M.S. St Mary’s March 2009
Joe Meadows M.S. St Mary’s March 2009 Breast Conservation Therapy (BCT) is a standard of care supported by years of data.
BCT refers to breast-conserving surgery (BCS) + RT.
27+ years of data supports BCT as a standard.
Six modern, prospective randomized trials found no significant differences when comparing BCT to mastectomy.
Clinical trials compared local recurrence, distant metastasis, and long-term survival.
Joe Meadows M.S. St Mary’s March 2009 Prospective Randomized Trials: BCT vs.Mastectomy
Joe Meadows M.S. St Mary’s March 2009 Prospective Randomized Trials: Lumpectomy +/- Radiation Therapy
Joe Meadows M.S. St Mary’s March 2009 So although BCT is equivalent to mastectomy in terms of recurrence and survival rates, it is still very underutilized. But even today, more than 15 years later, many women eligible for breast-conserving surgery are getting mastectomies.
2007 Cancer Facts & Figures American Cancer Society.
U.S. Department of Health and Human Services, Office on Women’s Health.
SEER Data 2000-2004 Incidence Rates, NCI.
The National Institutes of Health Consensus Statement on Treatment of Early-Stage Breast Cancer states: “Breast Conservation Surgery plus radiotherapy is preferable to total mastectomy because it provides survival equivalence while preserving the breast.” (Consensus statement on treatment of early-stage breast cancer. National Institutes of Health, 1992).
In 2007, upwards of 180,000 women will be eligible for breast conservation therapy. However, according to SEER data, only about 40% of eligible women receive BCT each year. Another 41% receive mastectomy and 19% get a lumpectomy without follow-up radiation therapy. In 2007, this means that over 108,000 women may not receive the preferred method of treatment for their early-stage breast cancer. And sadly, over 34,000 are risking recurrence by not having their recommended course of radiation therapy. An idea behind MammoSite Targeted Radiation Therapy and other forms of APBI is that this treatment modality can help increase the number of women who receive breast conservation therapy and help reduce the numbers of women who receive mastectomy and lumpectomy only. Under-Utilization of BCT 240,000 Breast Cancer Cases in 2007 1 ~180,000 Eligible for Breast Conservation Therapy (BCT) 2 ~72,153 40% ~34,273 19% ~73,957 41% Mastectomy BCT Lumpectomy No Radiation 108,230 3 No Radiation
Benefit of Post Op Treatment Doctors in some parts of the United States may be more old-fashioned and less likely to offer lumpectomy with radiation as an option for their patients, particularly their older patients . Such doctors may urge mastectomy , even for women who should be offered the choice. But recent research has shown that women 75 or older who get radiation after lumpectomy are more likely to live longer and remain free of breast cancer longer than women who do not get radiation. http://www.breastcancer.org/treatment/surgery/lumpectomy/index.jsp Joe Meadows M.S. St Mary’s March 2009
The evidence shows that lumpectomy followed by radiation is likely to be equally as effective as mastectomy for women with:
Only one site of cancer in their breast, and
Tumor under four centimeters, removed with clear margins (no cancer cells in the tissue surrounding the tumor).
Joe Meadows M.S. St Mary’s March 2009
Breast Conserving Therapy + = BCT candidate Joe Meadows M.S. St Mary’s March 2009 A. Tumor B. Lumpectomy specimen
Whole Breast or Partial? For patients with node-negative breast cancer who undergo breast conserving surgery (BCS), RT to the whole breast is standard adjuvant local treatment. Clearly demonstrated in randomized trials to provide local control and survival comparable to mastectomy . h ttp://www.medscape.com/viewprogram/8355
Six of 199 patients had Ipsilateral Breast Tumor Recurrences (IBTRs) were observed, for a 5-year and 10-year actuarial rate of 1.6% and 3.8%, respectively.
These numbers are considered to be equivalent to Whole Breast RT following BCS.
Requires most expertise !
(NOT for the faint of heart)
(22).IJROBP 2007;68(2) 341-6 Vicini FA et al
APBI –InterstitialCatheter “Our” First Experience
It was the first approach to APBI in Radiation Oncology.
This technique has the longest follow-up data to date.
This technique is still in use today at certain (not many) medical centers around the country.
The post-lumpectomy bed is “sandwiched” between two planes of needles to provide adequate dosing to it’s periphery
PROBLEM - Not many Residency programs today teach this level of brachytherapy expertise. Therefore, to emulate this positive experience required a re-engineering of the approach to breast APBI Brachytherapy
APBI - Mammosite HDR Unit * **Over 60,000 patients have been treated to date with Mammosite!
The device is placed in the post-lumpectomy cavity and inflated with saline and contrast to a volume at least as large as the lumpectomy cavity if not larger.
The larger the balloon fill volume, the better the dosimetric advantage of depth-dose since the Rx is 1cm beyond the balloon surface.
MammoSite Balloon Device
Simplified approach compared interstitial since it doesn’t require “creating” a cavity for the device.
APBI - Mammosite Various balloon shapes/sizes offer ability to implant a broad range of cavity shapes/volumes. 5 – 6 cm Sphere 4 x 6 cm Ellipsoidal 4 – 5 cm Sphere Balloon Configuration
Applicator is a balloon device with the tube in center
X-ray Tube HV Cable D (Gy) 34 Red 17 Orange 10.2 Yellow 6.8 Green 5.1 Blue 3.4 Dark Blue 1.7 Magenta 40 kV source in BrachyVision® D (Gy) 34 Red 17 Orange 10.2 Yellow 6.8 Green 5.1 Blue 3.4 Dark Blue 1.7 Magenta
APBI - Xoft Film dosimetry around this miniaturized x-ray tube shows a nearly spherical distribution of radiation http://www.xoftinc.com/images/pdf/posters/Poster_4.pdf
Miniature X-ray source inserted into a flexible cooling catheter
Delivers a single dose of electrons to the tissue around the lumpectomy cavity during surgery
Lead plate is placed to protect underlying tissues
Skin is moved out of the way of the radiation beam.
Very expensive technology of limited use
What happens if the FINAL pathology comes back with a + margin?? Aetna considers intraoperative radiation therapy experimental and investigational for the treatment of brain tumors, breast cancer , pancreatic cancer, cholangiocarcinoma, retroperitoneal sarcoma, osteosarcoma, and all other indications.
FDA Trial: Updated Results Benitez et al: ASBS April 2007 Am J Surg 194(4):456-62, 2007
36 (out of 43) evaluable patients/T1N0
Median follow-up: 66 months
83% Excellent/Good Cosmesis
No local or regional recurrences
Fat Necrosis: 9.3% (all asymptomatic)
Infection rate: 9.3%
Seromas: 32.6% (12% symptomatic)
Published APBI Results - All APBI Techniques - Dr.F.Vicini Beaumont Hospital Technique # Series # Patients Follow-Up (Range) % IBTR (Range) Interstitial 14 1166 27-113 0-9% Mammosite 12 3332 2-66 0-6% 3D Conformal 3D Conformal 7 367 10-36 0-2% Totals Totals 33 4865 2-113 0-9%