Greg Edmundson

Accelerated Treatment of Breast Cancer

PURPOSE Radiation therapy (RT) restricted to the tumor bed, by means of an interstitial implant, and lasting 4 to 5 days after lumpectomy was prospectively evaluated in early-stage breast cancer patients treated with breast-conserving therapy (BCT). The goals of the study were to determine whether treatment time can be reduced and whether elective treatment of the entire breast is necessary. MATERIALS AND METHODS Between January 1993 and January 2000, 174 cases of early-stage breast cancer were managed with lumpectomy followed by RT restricted to the tumor bed using an interstitial implant. Each brachytherapy patient was matched with one external-beam RT (ERT) patient derived from a reference group of 1,388 patients treated with standard BCT. Patients were matched for age, tumor size, histology, margins of excision, absence of an extensive intraductal component, nodal status, estrogen receptor status, and tamoxifen use. Median follow-up for both the ERT and brachytherapy groups was 36 months. RESULTS No statistically significant differences were noted in the 5-year actuarial rates of ipsilateral breast treatment failure or locoregional failure between ERT and brachytherapy patients (1% v 0%, P =.31 and 2% v 1%, P =.63, respectively). In addition, there were no statistically significant differences noted in rates of distant metastasis (6% v 3%, P =.24), disease-free survival (87% v 91%, P =.55), overall survival (90% v 93%, P =.66), or cause-specific survival (97% v 99%, P =.28). CONCLUSION Accelerated treatment of breast cancer using an interstitial implant to deliver radiation to the tumor bed alone over 4 to 5 days seems to produce 5-year results equivalent to those achieved with conventional ERT. Extended follow-up will be required to determine the long-term efficacy of this treatment approach.

The use of high-dose-rate brachytherapy alone after lumpectomy in patients with early-stage breast cancer treated with breast-conserving therapy

PURPOSE We present the preliminary results of our in-house protocol using outpatient high-dose-rate (HDR) brachytherapy as the sole radiation modality following lumpectomy in patients with early-stage breast cancer. METHODS AND MATERIALS Thirty-seven patients with 38 Stage I-II breast cancers received radiation to the lumpectomy cavity alone using an HDR interstitial implant with (192)Ir. A minimum dose of 32 Gy was delivered on an outpatient basis in 8 fractions of 4 Gy to the lumpectomy cavity plus a 1- to 2-cm margin over consecutive 4 days. RESULTS Median follow-up is 31 months. There has been one ipsilateral breast recurrence for a crude failure rate of 2.6% and no regional or distant failures. Wound healing was not impaired in patients undergoing an open-cavity implant. Three minor breast infections occurred, and all resolved with oral antibiotics. The cosmetic outcome was good to excellent in all patients. CONCLUSION In selected patients with early-stage breast cancer, treatment of the lumpectomy cavity alone with outpatient HDR brachytherapy is both technically feasible and well tolerated. Early results are encouraging, however, longer follow-up is necessary before equivalence to standard whole-breast irradiation can be established and to determine the most optimal radiation therapy technique to be employed.

Irradiation of the tumor bed alone after lumpectomy in selected Patients with early-stage breast cancer treated with breast conserving therapy

We present the interim findings of our in‐house protocol treating the tumor bed alone after lumpectomy with low‐dose‐rate (LDR) interstitial brachytherapy in selected patients with early‐stage breast cancer treated with breast conserving therapy (BCT).

Pelvic lymphadenectomy and transperineal interstitial implantation of ir 192 combined with external beam radiotherapy for bulky stage c prostatic carcinoma

From January 1983 until June 1987, 51 patients with locally advanced prostatic carcinoma (47 Stage C, 4 bulky B2) were treated at Mayo Clinic (33 patients) and at William Beaumont Hospital (18 patients) with (a) 5 Gy delivered pre-operatively in one fraction, (b) pelvic lymphadenectomy and (c) interstitial implantation of the prostate with Ir 192 seeds via a perineal template (the Martinez Universal Perineal Interstitial Template) to deliver 35 Gy, and (d) 30.6 Gy external beam therapy in 17 fractions to prostate only fields. Initial clinical response has been excellent. Local control, with a median follow-up of 45 months, has been 100% by clinical exam and 84.5% pathologically in the subset biopsied. Disease-free actuarial survival at 5 years is 89%. Major toxicity has been limited to the rectum, but a modification of the brachytherapy technique has reduced this sharply. We conclude that bulky Stage C prostatic carcinoma can be successfully treated by this aggressive combination of modalities with acceptable toxicity.

Cone-beam CT: applications in image-guided external beam radiotherapy and brachytherapy

Geometric uncertainties in radiotherapy result in the use of margins as a means to guarantee target coverage and normal tissue avoidance. The advantages of reducing these uncertainties are significant. Here, the authors report on the application of a new imaging technology to image-guidance in external beam radiotherapy and brachytherapy. Results are summarized.

Chapter 9 – Interventional Strategies to Optimize the Delivery of Radiation Therapy

IMAGING HIGHLIGHTS □ The increase in imaging information and advances in computer technology are allowing correction of the two main causes of treatment inaccuracy: uncertainty in defining clinical target volume (CTV) and variations in patient geometry and tumor movement.

98 The use of high dose rate brachytherapy alone after lumpectomy in patients with early stage breast cancer treated with breast conserving therapy

Purpose: We present the preliminary results of our in-house protocol using outpatient high-dose-rate (HDR) brachytherapy as the sole radiation modality following lumpectomy in patients with early-stage breast cancer. Methods and Materials: Thirty-seven patients with 38 Stage I‐II breast cancers received radiation to the lumpectomy cavity alone using an HDR interstitial implant with 192 Ir. A minimum dose of 32 Gy was delivered on an outpatient basis in 8 fractions of 4 Gy to the lumpectomy cavity plus a 1- to 2-cm margin over consecutive 4 days. Results: Median follow-up is 31 months. There has been one ipsilateral breast recurrence for a crude failure rate of 2.6% and no regional or distant failures. Wound healing was not impaired in patients undergoing an open-cavity implant. Three minor breast infections occurred, and all resolved with oral antibiotics. The cosmetic outcome was good to excellent in all patients. Conclusion: In selected patients with early-stage breast cancer, treatment of the lumpectomy cavity alone with outpatient HDR brachytherapy is both technically feasible and well tolerated. Early results are encouraging, however, longer follow-up is necessary before equivalence to standard whole-breast irradiation can be established and to determine the most optimal radiation therapy technique to be employed.

Interventional strategies to counter the effects of inter­ fraction treatment variation

Great strides have been made in recent years in the development of important techniques for treatment planning and delivery. There is optimism that the new conformal treatment methods, such as intensity modulation (IMRT) will ultimately lead to improved local control and/or reduced toxicity. However, our expectations must be guarded. The higher degree of conformation means that the risk of treatment failure will also be higher. It is imperative to ensure that the treatments are not only optimally planned, but also accurately implemented. Failure to minimize treatment error will not only undermine the treatment outcome, but also lead to the erroneous and dire conclusion that the advanced treatment methods are ineffectively.