Dr. Subir Nag et al are to be congratulated for their excellent,
thorough analysis and presentation of the use and role of brachytherapy in the
treatment of patients with breast cancer.
Brachytherapy: Long Time Coming
In 1896, Gocht used x-rays in the treatment of breast cancer,
1 year after Roentgen’s first report on his discovery. Radium was also used to
treat early and advanced breast cancer very soon after its discovery. In 1924,
Koenig reported a 5-year survival of 21% for stage I breast cancer and 17%
for stage II disease in patients treated with radium only.
In 1929, Keynes suggested that it might be possible to cure
breast cancer by means of irradiation. He described techniques in which radium
needles were implanted into the breast tumor, axilla, and occasionally, the
internal mammary node region. He chose this modality on the basis of previous
experiences in which he had used preoperative irradiation and noted complete
disappearance of the tumor when examined microscopically in about one-third of
McKittrick agreed with Keynes that interstitial irradiation
was of use for tumors that occupied no more than
one-quarter of the breast. He consid-ered interstitial irradiation to be of no
value in operable patients because of sequelae (pain, fibrosis, and late
The sequelae of brachytherapy led to its limited use until the
mid-1900s. At that time, the Europeans, especially the Frenchwho had
continued to use radium in combination with orthovoltage therapybegan to use
radium and other radioactive sources to give a boost dose to the tumor or tumor
bed. On the basis of work by European investigators, such as Pierquin,[5,6] the
use of brachytherapy as a boost for breast cancer was given credence.
In the recent past, a few investigators opposed its use. In
addition, the availability of the electron beam made boosting of the tumor site
more practical. As a result of these issues, brachytherapy, even as a local
boost, has been used only at a few centers in the United States.
Necessity for Guidelines
Since most radiation oncologists do not have extensive
experience in breast brachytherapy, it made good practical sense for the
American Brachytherapy Society (ABS) to develop guidelines for the clinical use
of this strategy. The result has been a well-prepared and well-written document.
There are multiple methods for the use of brachytherapy in the
treatment of breast cancer. Among these techniques are:
As the Sole Method of Treatment: In the past, this
method was used for patients with advanced disease. However, Dr. Kuske has begun
to show favorable results in patients with early-stage disease.[8,9]
As a Low-Dose-Rate Boost Following External-Beam
Irradiation: Although this method has been used in the United States, the
majority of cases have been treated in France.[5,6]
As a Boost Before External-Beam Irradiation: This is
the time of surgical excision of the lump.[7,10,11] We have treated over 600
patients using brachytherapy at the time of lumpectomy. We have noted excellent
local control, survival, and cosmetic results.
As a Mold to Treat Postmastectomy Recurrence on the
Chest Wall: The use of this method today would be very rare because of the
availability of the electron beam.
As a Low- or High-Dose Boost: This can be done with or
without external-beam irradiation.[13,14]
In the conservative treatment of the breast, the local tumor is
excised with a 1- to 2-cm margin of normal tissue. As mentioned above, an
implant can be performed at the time of lumpectomy.[10-12] However, the most
common approach has been to have the patient start on external-beam therapy to
the whole breast 1 to 2 weeks later. The adjacent nodes are treated, depending
on the location of the primary and status of the axillary nodes. The tumor bed
is then boosted with electrons or an interstitial implant (photons are rarely
used, because they are associated with sequelae). The interstitial therapy can
be administered at a high or low dose rate.
The ABS panel discusses the indications, use, and evaluation of
breast implants as the sole treatment modality following lumpectomy, as a boost
following whole-breast irradiation, and as a treatment of local recurrences. As
pointed out by the ABS, the use of brachytherapy as the sole method of treatment
to the tumor bed is being investigated in a randomized trial. At present, this
is not the recommended method of treatment, except in a randomized trial
setting. This is particularly true for patients with stage II disease, since a
higher percentage of their recurrences can occur outside of the tumor site.
Treat the Whole Breast
or Tumor Site?
For more than 100 years, the treatment of early breast cancer
has been based on the concept that the whole breast needs to be treated. This
has been supported by the fact that the whole breast is at risk for recurrent
disease. However, the majority of recurrences have occurred in the region of the
original tumor. As a result, a school of thought has arisen suggesting that it
should be possible to achieve a cure in the breast even if only the tumor site
in the breast is treated.[8, 9,13,14]
In summary, up until now, no real standards have been developed
for the use of brachytherapy in the breast. This paper establishes guidelines
that are sorely needed in the brachytherapy community. Dr. Nag and the panel
address important issues such as the clinical target volume, optimal volume,
type of interstitial implants, use of templates, high dose rate, and dosimetry.
Their work has resulted in a well-done reference article.
1. Gocht W: Therapeutische Verwendungen der Röntgenstrahlen.
Fortschr. Geb. Röntg-Strahl 1:14-22, 1897.
2. Koenig F: Geburtsh. Gynäk 87:270, 1924.
3. Keynes G: Treatment of primary carcinoma of the breast with
radium. Acta Radiol 10:393-401, 1929.
4. McKittrick LS: Interstitial radiation of cancer of the
breast. Ann Surg 106:631, 1937.
5. Pierquin B: Can we treat small breast cancers (operable
cancers) by radiotherapy alone? Ann Med Interne (Paris) 122:575-579, 1971.
6. Pierquin B, Raynal M, Chassagne D, et al: Radiothérapie
seule dans le traitement des cancers du sein. Conservative treatment of breast
cancer. Symp Int Strasbourg 1972, p 233. Paris, Masson, 1974.
7. Mansfield CM, Jewell WR: Intraoperative interstitial
implantation of iridium-192 in the breast. Radiology 150:600, 1984.
8. Kuske RR, Bolton JS, Wilenzick RM, et al: Brachytherapy as
the sole method of breast irradiation in TIS, T1, T2, N0-1 breast cancer. Int J
Radiat Oncol Biol Phys 30(S1):245, 1994.
9. Kuske RR, Bolton JS, Harrison W: RTOG 95-17. A phase I/II
trial to evaluate brachytherapy as the sole method of radiation therapy for
stage I and II breast carcinoma, pp 364. Radiation Therapy Oncology Group.
10. Krishnan L, Jewell WR, Mansfield CM, et al: Perioperative
interstitial irradiation of the conservative management of early breast cancer.
Int J Radiat Oncol Biol Phys 13:1661-1665, 1987.
11. Mansfield CM: Intraoperative Ir-192 implantation for early
breast cancer: Techniques and results. Cancer 66:1-5, 1990.
12. Mansfield CM, Komarnicky LT, Schwartz GF, et al: Ten year
results in 1070 patients with stages I and II breast cancer treated by
conservative surgery. Cancer 75(9):2328-2336, 1995.
13. Kestin LL, Jaffray DA, Edmundson GK, et al: Improving the
dosimetric coverage of interstitial high-dose rate breast implants. Int J Radiat
Oncol Biol Phys 46(1):35-43, 2000.
14. Vicini F, Kini VR, Chen P, et al: Irradiation of the tumor
bed alone after lumpectomy in selected patients with early-stage breast cancer
treated with breast conserving therapy. J Surg Oncol 70(1):33-40, 1999.