Articles courtesy of The Journal of The Center for Cancer and Blood Disorders, Vol. 1, May 2006

Accelerated Partial Breast Irradiation After Lumpectomy
Courtesy of The Journal of The Center for Cancer and Blood Disorders, Vol. 1, May 2006

An estimated 211,240 new cases of breast cancer occurred among American women in 2005. (1) About two-thirds of new breast cancer diagnoses presented when cancer was still confined to the primary site (localized stages 0 or I). (2) Clinical trials have conclusively shown that many women with early-stage breast cancer can be treated effectively with breast conservation surgery (BCT) followed by whole breast external beam radiation therapy (EBRT).

With EBRT lasting up to seven weeks, many early stage patients still choose mastectomy. Some find it impractical to take time from work or other responsibilities, or, especially in Texas, travel daily to treatment centers far from home. The chance of forgoing this therapy has indeed been thought to increase the farther away a woman lives from a radiation treatment center.

Brachytherapy, using high intensity radiation from a point source, is able to shorten the course of radiation treatment. In the past, post-lumpectomy brachytherapy required the insertion of between twenty and thirty needles with radiation sources into the remaining breast. There is now a more simple alternative.

Approved by the FDA in 2002, the MammoSite breast radiation system utilizes a high dose rate (HDR) brachytherapy applicator to provide accelerated partial breast irradiation (APBI). The entire course of therapy is completed in five days.

The surgeon who performed the lumpectomy utilizes ultrasound guidance to insert a balloon-tippled catheter into the cavity created by the lumpectomy. The inflated balloon shapes and compresses the tissue adjacent to the cavity into a nearly spherical shell surrounding the balloon. A radiation source is briefly placed through the catheter into the center of the balloon.

The result is irradiation to the tissue surrounding the lumpectomy cavity— where the risk of local recurrence is highest.

A typical clinical protocol for MammoSite prescribes a dose of 340 cGy b.i.d. at a distance of 1 cm from the surface of the balloon. Dose to overlying skin is the main dose-limiting factor for MammoSite treatment.

MammoSite treats the breast using a radiation source that is placed inside the body and is removed with each treatment. This has important advantages:

• Radiation is delivered from inside the breast directly to the area where cancer is most likely to recur. This limits the amount of radiation to healthy tissue, thereby reducing the potential for side effects.
• The therapy can be completed in only 5 days, and completed before starting adjuvant chemotherapy.
• Cosmetic outcome is improved, with less risk of change in breast contour or texture. (4)

These advantages of APBI led to a multi-institutional registry trial sponsored by the American College of Breast Surgeons. The registry documented 1403 patients with early stage breast cancer treated at 87 institutions by 223 different investigators. (5) Data collected included age of patient, tumor size, skin spacing, catheter pull rates and reasons, infection, radiation recall, cosmesis, and recurrence. Good to excellent cosmetic results are achieved in 88 percent of patients. (6) (7) (8). Low local recurrence rates of 4% at five years are similar to those seen after EBRT. (9)

Treatment planning requires CT imaging to digitize the path of the lumen through which the HDR wire passes, and to measure the dimensions of the balloon and its distance from the skin surface. A “Light-Speed”* CT system is available on-site at The Center for Cancer and Blood Disorders and is utilized prior to each session. Treatment is delivered by an Ir-192 tipped wire, which is introduced into the balloon for the time required to deliver the prescribed dose.

In keeping with our goal to provide cutting edge technology to north Texas physicians and their patients, MammoSite therapy is offered at The Center. At the time of this writing, ten Tarrant County surgeons have completed the necessary course to perform the procedure. About fifteen procedures have been performed.

Surgeons Comment on MammoSite Therapy

Sam Buchanan D.O. Associate Professor of Surgery University of North Texas Health Science Center “I share LaNasa’s enthusiasm for the MammoSite Radiation procedure. This treatment works remarkably well for increasing number of women diagnosed in the early stages of breast cancer. The role of the surgeon is to accurately place the MammoSite catheter in the lumpectomy cavity so the radiation oncologist can target, with great precision, the area with the highest possibility of recurrence. The MammoSite course I attended was excellent, and out local experience is rapidly increasing. I have been working with other surgeons who desire to learn this technique.”

Annette Elbert M.D. “Women juggle children, jobs, elderly parents, household chores, and more. A cancer diagnosis is emotionally devastating, not only because of the fear of this dreaded illness, but also because of the impact on our families. MammoSite is as much a quality of life issue as a medical issue. Shortening the time required for radiation by 85% is a great blessing for our patients. I believe MammoSite is a significant addition to our available breast cancer therapies. “The MammoSite course I attended was exceptional, and emphasized the required close cooperation between the surgeon and radiation therapist. I look forward to employing this state-of-the-art technique in cooperation with my radiation therapy colleagues.”

Anita Chow, M.D. “MammoSite breast radiation offers another treatment modality to those women with breast cancer who desire breast conservation. I’ve performed this procedure and found it to be easy on the patient. The course on performing the procedure was enjoyable and an excellent educational experience.”

Amelia Gunter, M.D. “MammoSite makes breast-conserving therapy a viable option for more patients. Many women choose mastectomy to avoid the inconvenience of traditional radiation therapy. MammoSite reduces the patient’s therapy time considerably. The MammoSite Therapy course I attended was excellent. I am enthusiastic about this technique and look forward to providing this procedure to my patients.”

From the Editor: Resolve to do it and it is no dream.

A few short years ago, a multi-disciplinary cancer center for Fort Worth was still a dream. It had been a dream since four Fort Worth oncologists merged their practices twelve years ago to form Texas Cancer Care. In the intervening years we have done more than dream - we have resolved and accomplished.

We have grown from a single office to a network with a new name, The Center for Cancer and Blood Disorders. We now consist of seventeen specialists in hematology, medical oncology, and radiation oncology. This includes five regional satellite offices in Weatherford, Cleburne, Burleson, Mineral Wells, and Fort Worth.

The doctors hold academic appointments at the UNT Medical School and are involved daily in teaching medical students and residents at all levels. And just one year ago we completed construction of a wonderful, new comprehensive cancer center in the hospital district.

This new Journal is another step in our “resolve” to create an academic cancer center of national stature. Published quarterly, each issue will review a single topic in depth. This will include new technologies for cancer diagnosis or treatment, current research programs, alternative or nutritional therapies, and other aspects of cancer treatment.

This issue is dedicated to the MammoSite Radiation Therapy System. Currently approved for women age forty-five and above who have undergone lumpectomy, MammoSite provides the significant benefits of irradiation in a fraction of the time required, while markedly limiting the radiation to normal tissues.

I hope you enjoy this initial issue, find it informative, and look forward to future publications. Comments, suggestions, criticisms, and contributions for possible publication are welcome at mross@txcc.com.

Wishing you and your patients well,

Michael Ross, MD
Editor

(1) http://seer.cancer.gov/csr/1975_2002/results_single/ sect_01_table.01.pdf

(2) http://seer.cancer.gov/csr/1975_2002/results_ merged/sect_04_breast.pdf

(3) Fisher, B. Reanalysis and results after 12 years of follow-up in a randomized clinical trial comparing total mastectomy with lumpectomy with or without irradiation in the treatment of breast cancer. N Engl J Med. 1995 Nov 30;333(22):1456-61.

(4) Breast J. 2005 Sep-Oct;11(5):303-5.

(5) Zannis, V, et al: Descriptions and outcomes of insertion techniques of a breast brachytherapy balloon catheter in 1403 patients enrolled in the American Society of Breast Surgeons MammoSite breast brachytherapy registry trial. Am J. Surg. 2005 Oct; 190(4): 530-8.

(6) Keisch, M et al. Initial clinical experience with the MammoSite breast brachytherapy applicator in women with early-stage breast cancer treated with breast-conserving therapy. Intl. Journal of Radiation Oncology Biol/Phys 55: 289-293, 2003.

(7) DiFronzo LA, et al. Breast conserving surgery and accelerated partial breast irradiation using the MammoSite system: initial clinical experience. Arch Surg. 2005 Aug;140(8):787-94.

(8) Vincini FA. First analysis of patient demographics, technical reproducibility, cosmesis, and early toxicity: results of the American Society of Breast Surgeons MammoSite breast brachytherapy trial. Cancer. 2005 Sep 15;104(6):1138-48.

(9) Baglan KL, Martinez, AA, Frazier, RC, et al: The use of high-dose rate brachytherapy alone after lumpectomy in patients with early-stage breast cancer treated with breast-conserving therapy. Intl. Journal of Radiation Oncology Biol/Phys 50: 1003-1011, 2001.