To boost or not to boost: decreasing radiation therapy in conservative breast cancer treatment when "inked" tumor resection margins are pathologically free of cancer

Feasibility of percutaneous excision followed by ablation for local control in breast cancer

PURPOSE

Percutaneous ablation of breast cancer has shown promise as a treatment alternative to open lumpectomy. We hypothesized that percutaneous removal of breast cancer followed by percutaneous ablation to sterilize and widen the margins would not only provide fresh naive tissue for tumor marker and research investigation, but also better achieve negative margins after ablation.

METHODS

Patients diagnosed by percutaneous biopsy (ultrasound or stereotactic-guided) with breast cancer ≤1.5 cm, >1 cm from the skin, and ≤1 cm residual disease and no multicentric disease by magnetic resonance imaging were accrued to this institutional review board-approved study. Patients were randomized to laser versus radiofrequency ablation. The ultrasound-guided ablation was performed in the operating room and followed by immediate excision, whole-mount pathology with proliferating cell nuclear antigen staining, and reconstruction.

RESULTS

Twenty-one patients were enrolled onto the study. Fifteen patients received radiofrequency ablation, and all showed 100% ablation and negative margins. Magnetic resonance imaging was helpful in excluding multicentric disease but less so in predicting presence or absence of residual disease. Seven of these patients showed no residual tumor and eight showed residual dead tumor (0.5 ± 0.7 cm, range 0.1-2.5 cm) at the biopsy site with clear margins. The laser arm (3 patients) pathology demonstrated unpredictability of the ablation zone and residual live tumor.

CONCLUSIONS

This pilot study demonstrates the feasibility of a novel approach to minimally invasive therapy: percutaneous excision and effective cytoreduction, followed by radiofrequency ablation of margins for the treatment of breast cancer. Laser treatment requires further improvement.

Can ‘boost’ be avoided in pre-invasive and early breast cancer with free surgical margins after breast conservation surgery and irradiation?

Guidelines concerning early stage breast cancer do not clearly recommend tumour bed boost dose after breast conserving surgery and irradiation when the resection margins are negative. Because the number of these patients is expected to increase, we evaluated the results of our treatment scheme in which the additional tumour bed dose was omitted. One hundred consecutive individuals with ductal carcinoma in-situ or stage I or II cancer of the breast were identified for this retrospective analysis. The observed ipsilateral breast tumour recurrence and 10-year disease-free survival rates were 4% and 91% respectively. Univariate analysis indicated that triple receptor negative tumour is the most independent prognostic risk factor. In conclusion, the observed low rate of local recurrence and many long-term survivors in this study seem to legitimize the omission of the tumour bed boost dose after whole breast irradiation in women with early carcinoma of the breast and free breast conserving surgical margins.

Inverse planning of energy-modulated electron beams in radiotherapy

The use of megavoltage electron beams often poses a clinical challenge in that the planning target volume (PTV) is anterior to other radiosensitive structures and has variable depth. To ensure that skin as well as the deepest extent of the PTV receives the prescribed dose entails prescribing to a point beyond the depth of peak dose for a single electron energy. This causes dose inhomogeneities and heightened potential for tissue fibrosis, scarring, and possible soft tissue necrosis. Use of bolus on the skin improves the entrant dose at the cost of decreasing the therapeutic depth that can be treated. Selection of a higher energy to improve dose homogeneity results in increased dose to structures beyond the PTV, as well as enlargement of the volume receiving heightened dose. Measured electron data from a linear accelerator was used as input to create an inverse planning tool employing energy and intensity modulation using bolus (e-IMRT). Using tools readily available in a radiotherapy department, the applications of energy and intensity modulation on the central axis makes it possible to remove hot spots of 115% or more over the depths clinically encountered. The e-IMRT algorithm enables the development of patient-specific dose distributions with user-defined positions of peak dose, range, and reduced dose to points beyond the prescription point.

Hematoma-Directed Ultrasound-Guided (HUG) Breast Lumpectomy

BACKGROUND

Needle localization breast biopsy (NLBB) is presently the primary means of localizing non-palpable lesions. Disadvantages of NLBB include vasovagal episodes, patient discomfort, and miss rates. Because hematomas naturally fill the cavity after vacuum-assisted breast biopsies (VABB), we hypothesized that ultrasound (US) could be used to find and accurately excise the actual biopsy site of non-palpable breast lesions without a needle.

METHODS

This is a retrospective study from January 2000 to July 2005. Electronic chart review identified patients with non-palpable breast lesions detected by means of mammogram who then underwent lumpectomy via NLBB or the hematoma-directed ultrasound-guided technique (HUG). HUG involved localizing the hematoma with a 7.5-MHz US probe and using the "line of sight" technique straight down toward the chest wall. A block of tissue encompassing the hematoma was then excised.

RESULTS

Localization procedures were performed in 186 patients-63 (34%) via needle localization and 123 (66%) via HUG. The previous VABB site in 100% of patients was successfully excised using HUG, 65 of 123 (53%) were benign and 58 of 123 (47%) were malignant; margins were positive in 13 of these 58 (22%). NLBB was successful in 100% of patients, 44 of 63 (70%) were benign and 19 of 63 (30%) were malignant; margins were positive in 14 of these 19 (73%). Margin positivity was significantly higher for NLBB than HUG (P = 0.0001, Fisher Exact).

CONCLUSIONS

This study suggests that HUG is more accurate in localizing non-palpable lesions than NLBB. By eliminating the additional procedure needed for NLBB, HUG may also be more time- and cost efficient. HUG makes VABB not only a less invasive diagnostic procedure, but also a localization procedure.

Improving local control with breast-conserving therapy

BACKGROUND

The risk of ipsilateral breast tumor recurrence (IBTR) after breast-conserving therapy (BCT) is associated with treatment and tumor-related variables, such as surgical margin status and the use of systemic therapy, and these variables have changed over time. Correspondingly, the authors of the current study hypothesized that the contemporary multidisciplinary management of breast carcinoma would lead to an improvement in IBTR rates after BCT.

METHODS

Between 1970 and 1996, 1355 patients with pathologic Stage I-II invasive breast carcinoma underwent BCT (breast-conserving surgery and adjuvant radiation therapy) at The University of Texas M. D. Anderson Cancer Center. Contemporary methods of analyzing surgical margins were in routine use by 1994. To analyze the effect of this variable and others, patient and tumor characteristics and IBTR rates in patients treated during 1994-1996 were compared with those in patients treated from 1970 to 1993.

RESULTS

Characteristics were similar in patients treated during 1994-1996 (n = 381) and those treated before 1994 (n = 974) except for patients aged >50 years (63.3% vs. 51.7%, P < 0.001), and patients who had a family history of breast carcinoma (37.9% vs. 30.8%, P = 0.017). Patients treated after 1994 were less likely to have positive or unknown margins (2.9 % vs. 24.1 %, P = 0.0001), more likely to receive chemotherapy (40.5% vs. 26%, P < 0.001), and more likely to receive hormonal therapy (33.3% vs. 19.4%, P < 0.001), but less likely to receive radiation boosts to the primary tumor bed (59.8% vs. 89%, P < 0.001). The 5-year cumulative IBTR rate was significantly lower among patients treated in 1994-1996 than among patients treated before 1994 (1.3% vs. 5.7%, P = 0.001) largely because of the drop in IBTR rates among patients aged < or = 50 years (1.4 % vs. 9.1 %, P = 0.0001). On multivariate analysis, age > 50 (hazards ratio [HR] = 0.401; P = 0.0001), presence of negative surgical margins (HR = 0.574; P = 0.017), and use of adjuvant hormonal therapy (HR = 0.402; P = 0.05) were independent predictors of improved 5-year IBTR-free survival. On subgroup analysis, use of chemotherapy was associated with increased IBTR-free survival among women aged < or = 50 years (HR = 0.383; P = 0.001). Although 5-year cumulative IBTR rates were lower among women aged > 50 years than among younger women before 1994 (2.6 % vs. 9.1%, P < 0.0001), no such difference was found in the group treated in 1994-1996 (1.2 % for age > 50 yrs vs. 1.4 % for < or = 50 yrs, P = 0.999).

CONCLUSIONS

The IBTR rate after BCT appears to be declining, especially among patients < 50 years of age. However, long-term follow-up is necessary to confirm this finding. This finding may reflect changes in surgical approaches and pathologic evaluation as well as an increased use of systemic therapy. The current low incidence of IBTR with multidisciplinary management of breast carcinoma may result in more patients choosing BCT over mastectomy.

MR imaging–guided breast ablative therapy

The integration of imaging and thermal therapy can provide a minimally invasive or even noninvasive alternative to breast surgery for small tumors. Ongoing trials seek to show safety and efficacy for laser, radiofrequency, microwave, cryoablation, and focused ultrasound surgery. To be successful, these therapies must achieve equivalent or even greater efficacy as surgical outcomes and must demonstrate total ablation of the dominant lesion with negative margins, while sparing normal tissue beyond the target tissue. Procedures have been validated by histopathology subsequent to resection.

Effect of margins on ipsilateral breast tumor recurrence after breast conservation therapy for lymph node-negative breast carcinoma

BACKGROUND

Breast conservative surgery (CS) with radiotherapy (RT) is the most commonly used treatment for early-stage breast carcinoma. However, there is controversy regarding the importance of the pathologic margin status on the risk of ipsilateral breast tumor recurrence (IBTR). The current study evaluated the effect of the pathologic margin status on IBTR rates in a cohort of women with lymph node-negative breast carcinoma treated with CS and RT.

METHODS

Between August 1980 and December 1994, 452 women with pathologically lymph node-negative breast carcinoma were treated with CS and RT at Westmead Hospital (Westmead, Australia). Central pathology review was performed for all women. The final margins were negative for 352 women (77.9%), positive (invasive and/or in situ) for 42 women (9.3%), and indeterminate for 58 women (12.8%). Information regarding an extensive intraductal component (EIC), lymphovascular invasion, pathologic tumor size, histologic grade, and nuclear grade was available for most women. After macroscopic total excision of the tumor, all women received whole-breast irradiation (usually 45-50.4 grays [Gy]) and the majority of women also received a local tumor bed boost (range, 8-30 Gy).

RESULTS

After a median follow-up of 80 months, 34 women (7.5%) developed an IBTR. The crude 5-year rates of IBTR for women with negative margins, positive margins, and indeterminate margins were 3.1%, 11.9%, and 6.9%, respectively. For women with negative margins, the 5-year and 10-year actuarial rates of freedom from IBTR were 96% and 92%, respectively, compared with 88% and 75%, respectively, for women with positive margins (P = 0.003). Univariate analysis demonstrated that the only factors associated with a significantly higher risk of IBTR were age at diagnosis (P < 0.050) and margin status (P = 0.005). Multivariate analysis showed that both age and margin status were independent predictors of IBTR. None of 24 patients with an EIC and negative margins were found to have developed an IBTR.

CONCLUSIONS

The results of the current study were comparable to other published reports and supported the association of higher IBTR rates with positive or indeterminate margins compared with negative, pathologic margins. Furthermore, young age (age < 35 years at diagnosis) was associated with the highest risk of IBTR regardless of margin status.

Intraoperative evaluation of lumpectomy margins by imprint cytology with histologic correlation: a community hospital experience

BACKGROUND

Several well-controlled studies have demonstrated significantly increased local recurrence rates in patients with low-stage breast carcinoma treated with breast conservation therapy in whom focally positive margins were not reexcised. Imprint cytology is a rapid technique for evaluating surgical margins intraoperatively, thus allowing reexcisions to be performed during the initial surgery. The large majority of studies on the use of intraoperative imprint cytologic examination of breast conservation therapy margins have been performed at university-based academic centers.

OBJECTIVE

To evaluate the utility of intraoperative imprint cytologic evaluation of breast conservation therapy margins in a community hospital setting.

METHODS

We retrospectively reviewed the intraoperative imprint cytology margins of 141 lumpectomy specimens that had been obtained from 137 patients between May 1997 and May 2001.

RESULTS

We evaluated 758 separate margins. On a patient basis, the sensitivity was 80%, the specificity was 85%, the positive predictive value was 40%, the negative predictive value was 97%, and the overall accuracy was 85%. There were no cytologically unsatisfactory margins.

CONCLUSION

Imprint cytology is an accurate, simple, rapid, and cost-effective method for determining the margin status of breast conservation therapy specimens intraoperatively in the community hospital setting. This method allows a survey of the entire surface area of the lumpectomy specimen, which is not practical using frozen section evaluation.

The role of boost irradiation in the conservative treatment of stage I-II breast cancer

In this article, we review the current status, indication, technical aspects, controversies, and future prospects of boost irradiation after breast conserving surgery (BCS). BCS and radiotherapy (RT) of the conserved breast became widely accepted in the last decades for the treatment of early invasive breast cancer. The standard technique of RT after breast conservation is to treat the whole breast up to a total dose of 45 to 50 Gy. However, there is no consensus among radiation oncologists about the necessity of boost dose to the tumor bed. Generally accepted criteria for identification of high risk subgroups, in which boost is recommended, have not been established yet. Further controversy exists regarding the optimal boost technique (electron vs. brachytherapy), and their impact on local tumor control and cosmesis. Based on the results of numerous retrospective and recently published prospective trials, the European brachytherapy society (GEC-ESTRO), as well as the American Brachytherapy Society has issued their guidelines in these topics. These guidelines will help clinicians in their medical decisions. Some aspects of boost irradiation still remain somewhat controversial. The final results of prospective boost trials with longer follow-up, involving analyses based on pathologically defined subgroups, will clarify these controversies. Preliminary results with recently developed boost techniques (intraoperative RT, CT-image based 3D conformal brachytherapy, and 3D virtual brachytherapy) are promising. However, more experience and longer follow-up are required to define whether these methods might improve local tumor control for breast cancer patients treated with conservative surgery and RT.

Long-term results (10 years) of intensive breast conserving therapy including a high-dose and large-volume interstitial brachytherapy boost (LDR/HDR) for T1/T2 breast cancer

BACKGROUND AND PURPOSE

During the past 15 years many retrospective studies and prospective randomized trials have been published supporting the use of breast conserving treatment (BCT) including surgery and radiotherapy. However, there are still many controversies on the necessary amount of resection, the width of the resection margins and the optimal radiation technique, dose and volume, in particular of the boost. In this retrospective study a large cohort of 410 women with early breast cancer treated with BCT including an interstitial brachytherapy (BT) boost is evaluated after a long follow-up period.

MATERIAL AND METHODS

In order to clarify the impact of the different treatment-related factors on local control, these were carefully discriminated, based on widely accepted classification and reporting systems for surgery as well as for radiotherapy. The surgical approach was classified according to EORTC criteria and a high rate of quadrantectomies (60%) was found. Dose and volume of interstitial BT is reported according to recommendations of ICRU 58, and reveals a significant radiation dose and volume: minimum target dose, mean central dose (MCD) and '85% of MCD' for low-dose rate (LDR) BT was mean 20, 28 and 24 Gy, for high-dose rate (HDR) BT it was mean '10, 15 and 13 Gy, respectively; the treated volume was 104 cc for LDR BT and 83 cc for HDR BT.

RESULTS

The actuarial rates for overall survival, disease-free survival and disease-specific survival were 97, 90 and 98% at 5 years and 85, 79 and 92% at 10 years. There have been only 16 breast recurrences in 410 treated patients resulting in a 5- and 10-year actuarial local recurrence rate of 2 and 3.9%, respectively; six recurrences (1.5%) were in the original quadrant. Except age and menopausal status, all tumour- and patient-related risk factors had no significant impact on local control.

CONCLUSIONS

Our data confirm that intensive BCT leads to excellent long-term results in terms of local control, masking classical risk factors. This high-dose and large-volume interstitial BT seems to be superior to classical BCT without BT.

Breast carcinoma treated by conservative surgery: results of postoperative external radiotherapy with photons only and a nonsplit supraclavicular field

Eighty-nine breasts in 85 patients were treated by lumpectomy and then radiotherapy from a Co-60 source only. The supraclavicular field was nonsplit. Eighty percent were in their 40s, 60s, or 70s with almost equal distribution. The majority of cases (80%) was T1 followed by T2 (18%). Axillary dissection was not done in 26% of patients. The majority (84%) had infiltrating ductal carcinoma; 6% had carcinoma in situ only. The dose to the breast including the boost was in the range of 6,000 cGy to 7,000 cGy in 96%, whereas in 4% it was in the range of 5,000 cGy. Forty-four patients (49%) with N0 did not have nodal irradiation. The dose to the nodes in the remaining patients ranged from 5,040 to 6,840 cGy. The cosmetic result was good to excellent in 99% of evaluated patients. There was telangiectasia in 1, arm edema in 2, no fibrosis in supraclavicular-tangential fields junction and no other soft-tissue or bone complications. Fifteen percent died; 6% had no evidence of cancer, and 9% had metastatic disease. Two had local recurrence, but with salvage mastectomy and systemic therapy were alive and well. The use of external photons only for breast irradiation and a nonsplit supraclavicular field yielded good results compared with alternative methods.

A shorter fractionation schedule for postlumpectomy breast cancer patients

PURPOSE

The purpose of this retrospective review was to determine the effectiveness of 40 Gy in 16 daily fractions in preventing local recurrence in postlumpectomy invasive breast cancer patients whose margins of resection were clear of tumor by at least 2 mm.

METHODS

Between September 1989 and December 1993, 294 breasts were treated with this regimen. The entire breast was treated, using a tangential parallel pair, with wedges as necessary, to a dose of 40 Gy in 16 daily fractions. No additional boost was given. The median duration of follow-up of surviving patients is 5.5 years. Recently, the patients' assessment of the cosmetic outcome of their treatment was obtained, using a mailed questionnaire.

RESULTS

The 5-year actuarial breast-relapse rate was 3.5%, with an overall 5-year survival and disease-specific survival of 87.8% and 92.1%, respectively. In response to the cosmesis questionnaire, 77% of patients stated they were either extremely or very satisfied with the overall appearance of the breast, 19.5% moderately satisfied, and 3.5% either slightly or not at all satisfied. The corresponding responses for overall level of comfort of the breast were 79%, 16.5%, and 4.5% respectively.

CONCLUSION

This regimen is very effective at preventing recurrent breast cancer in this group of patients, and it provides a high level of patient satisfaction with cosmetic outcome. Its short duration offers the added advantage of a more efficient use of resources and greater patient convenience.

The impact of dose-specification policies upon nominal radiation dose received by breast tissue in the conservation treatment of breast cancer

PURPOSE

In the context of breast conservation treatment, absorbed dose is influenced by (1) prescribed nominal dose, and (2) dose-specification characteristics employed. Breast doses are generally specified either at tangent isocenter, varying anatomical points within the breast, or at isodoses varying from 90% to 100%. Boost doses are generally specified at 80-100%.

METHODS

An idealized axial slice of breast tissue at central axis is presented. Assuming varying dose-specification characteristics, absorbed doses are normalized and compared to those received by nominal prescriptions of 46 Gy to the breast and 20 Gy to the boost volume, both specified at 100%.

RESULTS

Absorbed doses vary from the normalized total of 66 Gy (with specification of breast and boost at 100%) in gradations up to a maximum of 76.11 Gy (when breast dose is specified at the 90% isodose and boost dose at 80%), a 13.3% difference.

CONCLUSION

The impact of dose specification is largely ignored in the breast irradiation literature and unappreciated in clinical practice. Its impact, however, is illustrated as dwarfing modest nominal dose escalations commonly recommended and prescribed among margin compromised patients. Progress in delineation of a dose-response relationship for treatment of breast cancer requires consensus as to dose specification. Arguments are offered that ICRU Report 50 dose-specification standards, as verified for reproducibility by the EORTC (22881/10882) trial group, constitutes the best data source currently available from which dose-specification consensus may be reached (1, 2). Dose to PTV(1) (whole breast plus 1- to 2-cm margin) should be specified at the tangent beam intersection on the central plane or, where such point is irrelevant, at two-thirds distance from dorsal beam edge to skin along the perpendicular breast bisector. Where irradiated via electrons, dose to the boost PTV(2) (lumpectomy cavity plus 1- to 3-cm margins) should be specified at 90%. Electron energy sufficient to provide 85% isodose coverage to all aspects of PTV(2) is recommended.

Cost-effectiveness of adding an electron-beam boost to tangential radiation therapy in patients with negative margins after conservative surgery for early-stage breast cancer

PURPOSE

Electron-beam boosts (EBB) are routinely added after conservative surgery and tangential radiation therapy (TRT) for early-stage breast cancer. We performed an incremental cost-utility analysis to evaluate their cost-effectiveness.

METHODS

A Markov model examined the impact of adding an EBB to TRT from a societal perspective. Outcomes were measured in quality-adjusted life years (QALYs). On the basis of the Lyon trial, the EBB was assumed to reduce local recurrences by approximately 2% at 10 years but to have no impact on survival. Patients' utilities were used to adjust for quality of life. Given the small absolute benefit of the EBB, baseline utilities were assumed to be the same with or without it, an assumption evaluated by Monte Carlo simulation. Direct medical, time, and travel costs were considered.

RESULTS

Adding the EBB led to an additional cost of $2,008, an increase of 0.0065 QALYs and, therefore, an incremental cost-effectiveness ratio of over $300,000/QALY. In a sensitivity analysis, the ratio was moderately sensitive to the efficacy and cost of the EBB and highly sensitive to patients' utilities for treatment without it. Even if patients do value a small risk reduction, the mean cost-effectiveness ratio estimated by the Monte Carlo simulation remains high, at $70,859/QALY (95% confidence interval, $53,141 to $105,182/QALY).

CONCLUSION

On the basis of currently available data, the cost-effectiveness ratio for the EBB is well above the commonly cited threshold for cost-effective care ($50,000/QALY). The EBB becomes cost-effective only if patients place an unexpectedly high value on the small absolute reduction in local recurrences achievable with it.

Cosmetic outcome in patients receiving an interstitial implant as part of breast-conservation therapy

PURPOSE

To study factors related to breast cosmetic outcome in patients treated with an interstitial implant as part of breast-conservation therapy.

MATERIALS AND METHODS

One hundred fifty-six patients with stage I or II breast carcinoma who received 50 Gy of external-beam irradiation followed by a 20-Gy interstitial boost were examined. The dose homogeneity index (DHI) was calculated for each evaluable implant and was examined in light of other patient-, treatment-, and tumor-related variables previously demonstrated to affect cosmesis.

RESULTS

Of the variables examined, both the DHI (P = .021) and the total excision volume (P = .019) were significantly related to cosmetic outcome (excellent vs less than excellent) in a univariate model. In the multivariate analysis, only the total excision volume remained significant (P = .032). The mean total excision volume +/- SD in patients with excellent cosmetic outcome (81.8 cm3 +/- 84.0) was significantly less than that in patients with less than excellent cosmetic outcome (120 cm3 +/- 84). The probability of excellent cosmetic outcome linearly increased with an increase in DHI. The mean DHI was 0.74 +/- 0.12 for the cases with excellent cosmetic outcome and 0.68 +/- 0.10 for those with less than excellent cosmetic outcome.

CONCLUSION

To achieve optimal cosmesis, DHI should be maximized. The volume of tissue removed, however, remains the most significant determinant.

Assessing margin status

As little time ago as 1991 the NIH Consensus conference could not agree on the need for negative margins. Today, negative margin status has become a prerequisite for BCT recognizing that positive margins impact negatively on local recurrence rates. The science of margin evaluation is fast becoming recognized to play a key role in providing patients with the opportunity for breast conservation therapy as well as the best possible cosmetic result. Preoperative factors that predict a greater likelihood of failure to obtain margins such as larger tumor size and positive lymph nodes are fixed and can only be dealt with by taking larger biopsies. RODEO-MRI can preoperatively predict probability of success or failure and can actual better define tumor dimensions and extent and help plan excisions. Use of intraoperative US may be a future tool used to facilitate the excision of non-palpable and possibly palpable tumors. Intraoperative pathological assessment should not be performed by frozen section but consideration given to cytological assessment so as to allow feedback to the surgeon intraoperatively as to which margin needs more attention. Finally, using all the above methods of obtaining negative margins, the surgeon may have the ability to impact the outcome of breast cancer surgery and recurrence.

Use of touch preps for diagnosis and evaluation of surgical margins in breast cancer

BACKGROUND

The best cosmetic results with conservative breast surgery are obtained at the time of initial excisional biopsy. The usefulness of the touch prep (TP) technique was evaluated for accuracy in diagnosis as well as in evaluation of margins at the time of original breast biopsy.

METHODS

Four hundred twenty-eight consecutive patients with breast masses seen from January 1993 to December 1994 were evaluated prospectively using TP.

RESULTS

Three hundred forty-five benign and 83 malignant tumors were evaluated. Tumors ranged in size from microscopic to 8 cm. Pathologic diagnosis was correct as compared to permanent section in 99.3%. The three carcinomas missed on TP were focal and in situ. Sensitivity was 96.39%, and specificity was 100%. Positive predictive value was 100%, and negative predictive value was 99.3%. For margin evaluation, the sensitivity and specificity were both estimated to be 100%.

CONCLUSIONS

TP has the advantage of being a simple, quick (2 to 3 minutes), safe (no loss of diagnostic material), and accurate method for diagnosis and estimation of tumor margins at the time of the original surgery.

Low-dose-rate brachytherapy as the sole radiation modality in the management of patients with early-stage breast cancer treated with breast-conserving therapy: preliminary results of a pilot trial

PURPOSE

We present the preliminary 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).

METHODS AND MATERIALS

Since March 1, 1993, 60 women with early-stage breast cancer were entered into a protocol of tumor bed irradiation only using an interstitial LDR implant with iodine-125. Patients were eligible if the tumor was < or = 3 cm, margins were > or = 2 mm, there was no extensive intraductal component, the axilla was surgically staged, and a postoperative mammogram was performed. Implants were placed using a standardized template either at the time of reexcision or shortly after lumpectomy. A total of 50 Gy was delivered at 0.52 Gy/h over a period of 96 h to the lumpectomy bed plus a 2-cm margin. Perioperative complications, cosmetic outcome, and local control were assessed.

RESULTS

The median follow-up for all patients is 20 months. Three patients experienced minimal perioperative pain that required temporary nonnarcotic analgesics. There have been four postoperative infections which resolved with oral antibiotics. No significant skin reactions related to the implant were noted and no patient experienced impaired would healing. Early cosmetic results reveal minimal changes consisting of transient hyperpigmentation of the skin at the puncture sites and temporary induration in the tumor bed. Good to excellent cosmetic results were noted in all 19 patients followed up a minimum of 24 months posttherapy. To date, 51 women have obtained 6-12-month follow-up mammograms and no recurrences have been noted. All patients currently have no physical signs of recurrence, and no patient has failed regionally or distantly.

CONCLUSION

Treatment of the tumor bed alone with LDR interstitial brachytherapy appears to be well tolerated, and early results are promising. Long-term follow-up of these patients is necessary to establish the equivalence of this treatment approach compared to standard BCT, however.

Long-term outcome with interstitial brachytherapy in the management of patients with early-stage breast cancer treated with breast-conserving therapy

PURPOSE

We reviewed our institution's experience with interstitial implant boosts to determine their long-term impact on local control and cosmetic results.

METHODS AND MATERIALS

Between January 1, 1980 and December 31, 1987, 390 women with 400 cases of Stage I and II breast cancer were managed with breast-conserving therapy (BCT) at William Beaumont Hospital. All patients were treated with an excisional biopsy and 253 (63%) underwent reexcision. Radiation consisted of 45-50 Gy external beam irradiation to the whole breast followed by a boost to the tumor bed to at least 60 Gy using either electrons [108], photons [15], or an interstitial implant [277] with either 192Ir [190] or 125I [87]. Long-term local control and cosmetic outcome were assessed and contrasted between patients boosted with either interstitial implants, electrons, or photons.

RESULTS

With a median follow-up of 81 months, 25 patients have recurred in the treated breast for a 5- and 8-year actuarial rate of local recurrence of 4 and 8%, respectively. There were no statistically significant differences in the 5- or 8-year actuarial rates of local recurrence using either electrons, photons, or an interstitial implant. Greater than 90% of patients obtained a good or excellent cosmetic result, and no statistically significant differences in cosmetic outcome were seen whether electrons, photons, or implants were used.

CONCLUSIONS

We conclude that patients with Stage I and II breast cancer undergoing BCT and judged to be candidates for boosts can be effectively managed with LDR interstitial brachytherapy. Long-term local control and cosmetic outcome are excellent and similar to patients boosted with either electrons or photons.

CT planning of boost irradiation in radiotherapy of breast cancer after conservative surgery

BACKGROUND AND PURPOSE

A study was performed to compare the accuracy of clinical treatment set-up and CT planning of boost irradiation in radiotherapy of breast cancer.

MATERIAL AND METHODS

Between September 1993 and October 1994, 45 women who underwent breast conserving surgery and irradiation containing a boost to the tumour bed were investigated. Prospective evaluation of CT planning of the boost was carried out. The target volume/boost field, electron energy and treatment set-up had been defined on the basis of clinical examination, initial and postsurgical mammograms by one radiotherapist. Next, a planning CT was performed in treatment position and a CT-based treatment plan was calculated according to a target volume defined by another radiotherapist. The clinical treatment set-up was imported into our computer planning system and the resulting isodose plots were compared with those from CT planning and reviewed critically.

RESULTS

The clinically defined treatment set-up had to be modified in 80% of the patients. Most discrepancies observed were related to the size of the boost field itself and the chosen electron energy. Minor changes had to be made with respect to angle of table and gantry.

CONCLUSIONS

Critical review of the isodose plots from both methods showed clear advantages for CT planning. Guidelines for target definition in CT planning of boost irradiation and subgroups of patients benefiting from this technique are described.

[Role of radiotherapy in the management of adenocarcinoma of the breast accessible to conservative surgery]

Standard treatment for limited stage adenocarcinoma of the breast includes lumpectomy (or a quadrantectomy), axillary node dissection, regional radiation therapy and, if the prognostic factors are unfavourable, chemotherapy and/or hormone therapy. This is supported by the results of American and European randomised trials. There have been many attempts at improving the modalities of conservative surgery and postoperative radiation therapy in order to maximize local control and minimize late sequellae. It is also likely that induction chemotherapy and external beam radiotherapy applied in selected cases increase the proportion of patients who can be offered conservative surgery.

Does the placement of surgical clips within the excision cavity influence local control for patients treated with breast-conserving surgery and irradiation

PURPOSE

A number of authors have demonstrated the importance of using surgical clips to define the tumor bed in the treatment planning of early-stage breast cancer. The clips have been useful in delineating the borders of the tangential fields, especially for very medial and very lateral lesions as the boost volume. If surgical clips better define the tumor bed, then a reduction in true or marginal recurrences should be appreciated. We sought to compare the incidence of breast recurrence in women with and without surgical clips, controlling for other recognized prognostic factors.

METHODS AND MATERIALS

Between 1980 and 1992, 1364 women with clinical Stage I or II invasive breast cancer underwent excisional biopsy, axillary dissection, and definitive irradiation. Median follow-up was 60 months. Median age was 55 years. Seventy-one percent of patients were path NO, 22% had one to three nodes, and 7% had > than four nodes. Sixty-one percent were ER positive and 44% PR positive. Margin status was negative in 62%, positive in 10%, close in 9%, and unknown in 19%. Fifty-seven percent of women underwent a reexcision. Adjuvant chemotherapy + tamoxifen was administered in 29%, and tamoxifen alone in 17%. Surgical clips were placed in the excision cavity in 556 patients, while the other 808 did not have clips placed. All patients had a boost of the tumor bed. Patients had their boost planned with CT scanning or stereo shift radiographs. No significant differences between the two groups were noted for median age, T stage, nodal status, race, ER/PR receptor status, region irradiated, or tumor location. Patients without clips had negative margins less often, a higher rate of unknown or positive margins and more often received no adjuvant therapy compared to patients with surgical clips.

RESULTS

Twenty-five and 27 patients with and without surgical clips, respectively, developed a true or marginal recurrence in the treated breast. The actuarial probability of a breast recurrence was 2% at 5 years and 5% at 10 years for patients without clips compared to 5 and 11%, respectively, for patients with clips (p=0.01). Comparing the breast recurrence rates for patients with and without clips there was no significant difference for the following factors: chemotherapy, tamoxifen, negative, positive or close margins, reexcision, N1, and central or inner primary. Increased rates of breast recurrence were noted for patients with clips for the following variables: no adjuvant treatment (p < 0.001), unknown margins (p < 0.001), a single excision (p = 0.003), path NO (p = 0.001), and outer location (p= 0.02). A forward stepwise multivariate analysis for all 1364 patients was performed using the aforementioned variables as well as the presence or absence of surgical clips and the primary surgeon. The surgeon (p = 0.03) and no adjuvant treatment (p = 0.01) significantly influenced breast recurrence. For patients with surgical clips the 10 year isolated breast recurrence rate was 21% for a single surgeon vs. 6% in the remainder of the group (p = 0.01). For patients with clips, this surgeon had unknown margins in 48% of cases compared to 10% overall (p = 0.001). Excluding this surgeon from analysis the isolated breast recurrence for patients with clips was 6 vs. 5% for patients without clips (p = 0.18).

CONCLUSIONS

Overall, there was a significant difference in the 10-year breast recurrence rate favoring women without clips despite more adverse prognostic factors. There was no difference in the breast recurrence rate for patients with or without surgical clips if careful attention to margin status was addressed. Failure to ink the surgical specimen resulting in unknown margins cannot be compensated for with the placement of .

Brachytherapy or electron beam boost in conservation therapy of carcinoma of the breast: a nonrandomized comparison

PURPOSE

The results of breast-conservation therapy using breast irradiation and a boost to the tumor excision site with either electron beam or interstitial 192Ir implant are reviewed.

METHODS AND MATERIALS

A total of 701 patients with histologically confirmed Stage T1 and T2 carcinoma of the breast were treated with wide local tumor excision or quadrantectomy and breast irradiation. The breast was treated with tangential fields using 4 or 6 MV photons to deliver 48 to 50 Gy in 1.8 to 2 Gy daily dose, in five weekly fractions. In 80 patients the regional lymphatics were irradiated. In 342 patients with Stage T1 and 107 with Stage T2 tumors, boost to the primary tumor excision site was delivered with 9 MeV and, more frequently, with 12 MeV electrons. In 91 patients with Stage T1 and 38 patients with Stage T2 tumors an interstitial 192Ir implant was performed. Tumor control, disease-free survival, cosmesis, and morbidity of therapy are reviewed. Minimum follow-up is 4 years (median 5.6 years; maximum, 24 years).

RESULTS

The overall local tumor recurrence rates were 5% in the T1 and 11% in the T2 tumor groups. There was no significant difference in the breast relapse rate in patients treated with either electron beam or interstitial 192Ir boost. Regional lymph node recurrences were 1% in patients with T1 and 5% with T2 tumors. Distant metastases were recorded in 5% of the T1 and 23% of the T2 groups. The 10-year actuarial disease-free survival rates were 87% for patients with T1 and 75% with T2 tumors. Disease-free survival was exactly the same in patients receiving either electron beam or interstitial 192Ir boost. Cosmesis was rated as excellent/good in 84% of patients with T1 tumors treated with electron beam and 81% of patients treated with interstitial implant, and 74 and 79% respectively, in patients with T2 tumors.

CONCLUSIONS

Breast-conservation therapy is an effective treatment for patients with T1 and T2 carcinoma of the breast. There is no difference in local tumor control, disease-free survival, cosmesis, or morbidity in patients treated with either electron beam or interstitial 192Ir implant boost. Clinical trials in progress will further elucidate this controversial subject.

Early breast cancer: influence of type of boost (electrons vs iridium-192 implant) on local control and cosmesis after conservative surgery and radiation therapy

Between December 1981 and December 1988, 329 consecutive patients with stage I and II breast cancers who underwent wide excision (n = 261) or quadrantectomy (n = 68) with (n = 303) or without (n = 26) axillary dissection were referred to radiotherapy. Final margins of resection were microscopically free from tumor involvement in all cases. Radiotherapy consisted in 40-45 Gy over 4-4.5 weeks to the breast, with (n = 168) or without (n = 161) regional nodal irradiation of 45-50 Gy over 4.5-5 weeks. A mean booster dose of 15 Gy was delivered to the primary site by iridium-192 implant in 169 patients (group 1) or by electrons in 160 patients (group 2). Twenty-seven percent (n = 88) of patients received tamoxifen for > or = 2 years. Adjuvant chemotherapy was administered in 22% (n = 71) of patients. Groups 1 and 2 were not strictly comparable. Group 1 patients were significantly younger, had smaller tumors, were treated with cobalt at 5 x 2 Gy per week and axillary dissection was more frequently performed. Group 2 patients were more frequently bifocal and more frequently treated by quadrantectomy and tamoxifen, and irradiation used accelerator photons at 4 x 2.50 Gy per week. No difference in terms of follow-up and survival rates was observed between the two groups. For all patients the 5- and 10-year local breast relapse rates were 6.7% and 11%, respectively. No difference was observed regarding local control either by the electron or the iridium-192 implant boosts. Axillary dissection and age had an impact on the breast cosmetic outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Inaccuracies in using the lumpectomy scar for planning electron boosts in primary breast carcinoma

PURPOSE

To determine the accuracy of using the lumpectomy scar, specifically the midpoint or center of the scar, to define the tumor bed in the electron beam boost for the treatment of early stage breast carcinoma.

METHODS AND MATERIALS

Electron boost simulation films from 316 cases of early breast carcinoma treated with lumpectomy and radiotherapy were reviewed. For each case which had surgically placed lumpectomy bed clips (N = 316), four clinical set-up methods ("hypothetical fields") of several field sizes were compared to the actual location of the tumor bed (as defined by the surgical clips). Each method was based on using the center of the scar as the center of the field and is described as follows: Method 1 uses a standard circular cone of a given diameter, method 2 also uses circular cones, but the diameter is based on the scar length; method 3 uses an oval field in which a constant margin is kept around the scar; method 4 results in an oblong field in which a 2 cm margin is placed on the lateral edge of the scar, but a larger margin around the center of the scar. The adequacy of each of these popular clinical set-up techniques was then analyzed for the population as a whole. "Inadequate" coverage was defined as any portion of the field edge coming within 1 cm of at least one surgical clip.

RESULTS

(1) Method 1: Inadequate coverage was found in 43%, 26%, and 17% of cases, using 7, 8, and 9 cm cones, respectively. (2) Method 2: Inadequate coverage was found in 88%, 61%, 36% and 20% of cases, with field size = scar length + 0, 2, 3, and 4 cm, respectively. (3) Method 3: Inadequate coverage was found in 34%, 17%, and 10% of cases, using 3, 3.5, and 4 cm margins, respectively. (4) Method 4: Inadequate coverage was found in 36% and 24% of cases using 3.5 and 4 cm margins around the scar center, respectively. Inadequate coverage was found in 51% and 42% of cases using margins equal to one-half the scar length or one-half the scar length + 1 cm, respectively.

CONCLUSION

We conclude that the lumpectomy scar is often a poor indicator of the location of the underlying tumor bed as defined by surgical clips. We recommend the use of clip placement and simulation of the electron boost to maximize target definition.

Is frozen section analysis of reexcision lumpectomy margins worthwhile? Margin analysis in breast reexcisions

BACKGROUND

The authors performed reexcision lumpectomy on patients with breast cancer with tumor at or close to the resection margin or if the margin status was unknown. Frozen section analysis (FSA) of reexcision lumpectomy margins was performed to allow additional excision of margins or mastectomy, saving the patient another operation or an additional radiation boost.

METHODS

The authors reviewed the accuracy of FSA of margins in 107 patients undergoing reexcision lumpectomy between 1987 and 1992. There were 359 frozen sections performed on 156 specimens. Sensitivity and specificity of FSA for each frozen section margin, specimen, and patient were evaluated, as was gross inspection of tumor involvement at the resection margins. The accuracy of each pathologist's use of FSA also was evaluated.

RESULTS

FSA sensitivity per frozen section margin, specimen, and patient was 0.90, 0.89, and 0.85, respectively. The specificity of gross inspection was 0.97, 0.96, and 0.96 (sensitivity, 0.44), which was significantly less accurate than that of FSA (P = 0.0015) or permanent section (P = 0.019). There was no significant discordance between FSA and permanent section. Of 19 pathologists doing FSA, 6 evaluated 10 or more specimens. The error rate ranged from 4% to 10% among pathologists with 10 or more readings, whereas 12 of 13 pathologists with fewer readings had no errors. The final pathologist had a 100% error rate, significantly worse (range, P = 0.0085-0.02) than any experienced pathologist. Thirty-four (32%) patients underwent additional excision (24 patients) or mastectomy (10 patients) based on the results of FSA, which saved the patients from undergoing another operation. No one required an additional operation or a mastectomy because of a false FSA result.

CONCLUSION

FSA is safe and accurate in evaluating reexcision lumpectomy margins. Gross inspection is not reliable in margin evaluation. FSA saved an additional operation 32% of the time. Obtaining clear margins during one procedure eliminates the necessity of an additional radiation boost and probably will improve cosmesis.

Patient population analysis in EORTC trial 22881/10882 on the role of a booster dose in breast-conserving therapy

The changing composition of the patient population in breast cancer, which has been reported over the last decade, has important consequences for prognosis. In the present trial, an analysis of the population in an EORTC trial (22881/10882) on breast-conserving therapy was conducted. A shift towards earlier stages has been seen stage per stage, therefore better survival and local control rates are likely to be expected in comparison to previously published series. The majority of tumours in this trial were small, with a median clinical size of 2 cm and a median pathological size of 1.5 cm. A substantial number of lesions were detected in a pre-clinical stage (17.8%). Nodal involvement was present in only 19% of all patients and usually in only a low number of nodes (only 4% of all patients had four or more nodes invaded). The median number of nodes examined was 12, the difference between institutions was large. There was a significant correlation between the number of nodes examined, the percentage of patients with positive nodes (P = 0.03) and the percentage of patients with massive axillary invasion (P = 0.003). The correlation between clinical evidence and pathological invasion of the axillary nodes showed that 15% of the clinical examinations were false-negative and 51% were false-positive. Pathological nodal invasion could be clinically predicted in only 31% of patients, and consequently clinical examination of the axilla was a poor predictor of prognosis in this study. Pathological invasion of axillary lymph nodes was better correlated to pathological tumour size than clinical or radiological size.

Local failure and margin status in early-stage breast carcinoma treated with conservation surgery and radiation therapy

OBJECTIVE

The authors determined whether microscopically positive surgical margins are detrimental to the outcome of early stage breast cancer patients treated with conservation surgery and radiation therapy.

SUMMARY BACKGROUND DATA

The optimal extent of breast surgery required for patients treated with conservation surgery and radiation therapy has not been established. To achieve breast preservation with good cosmesis, it is desirable to resect as little normal tissue as possible. However, it is critical that the resection does not leave behind a tumor burden that cannot be adequately managed by moderate doses of radiation. It is not known whether microscopically positive surgical margins are detrimental to patient outcome.

METHODS

The records of 259 consecutive women (262 breasts) treated with local excision (complete removal of gross tumor with a margin) and axillary dissection followed by radiation therapy for clinical stage I and II infiltrating ductal breast cancer at Duke University Medical Center and the University of North Carolina between 1983 and 1988 were reviewed. Surgical margins were considered positive if tumor extended to the inked margins; otherwise the margins were considered negative. Margins that could not be determined, either because the original pathology report did not comment on margins, or because the original specimen had not been inked were called indeterminate.

RESULTS

Of the 262 tumors, 32 (12%) had positive margins, 132 (50%) had negative margins, and the remaining 98 (38%) had indeterminate margins. There were 11 (4%) local failures; 3/32 (9%) from the positive margin group, 2/132 (1.5%) from the negative margin group, and 6/98 (6%) from the indeterminate group. The actuarial local failure rates at 5 years were 10%, 2%, and 10%, respectively, p = 0.014 positive vs. negative, p = 0.08 positive vs. indeterminate (log rank test). Margin status had no impact on survival or freedom from distant metastasis; 63 patients who originally had positive or indeterminate margins were re-excised. Two of 7 with positive margins after re-excision versus 1/56 rendered margin negative had a local recurrence.

CONCLUSIONS

The authors recommend re-excision for patients with positive margins because of improved local control of those rendered margin negative and identification of those patients at high risk for local failure (those who remain positive after re-excision). Because margin status impacts on local control, tumor margins after conservation surgery should be accurately determined in all patients.

Radiation therapy in breast conservation patients and postmastectomy

Radiation has played a continuous but changing role in the management of breast cancer. At Memorial Hospital, the past 10 years have seen a marked increase in breast conserving therapy, and changing indications for postmastectomy adjuvant radiation.

Treatment of early breast cancer with conservation of the breast. A review

This paper reviews the current status of conservative treatment for early breast cancer. While the first patients were treated with such techniques more than 60 years ago, it is during the last decade that randomized trials have confirmed that such treatment is comparable to mastectomy in preventing breast cancer death. Radiotherapy to the breast after local tumour excision is important to prevent local breast relapse, but it is not clear whether it has any influence on the risk of distant metastases. Several questions remain to be answered. While most investigators agree that the breast should receive a radiation dose of about 50 Gy in 5 weeks, there is no general agreement about the need for a tumour bed booster dose. Considering patients with tumour infiltration at the surgical resection line for whom it is not possible for cosmetic reasons to perform re-resection, it is not clear whether an acceptable local control rate can be achieved through application of a high booster dose in the tumour bed. More trials are needed to show whether certain patients with small invasive carcinomas should be treated with wide local excision without radiotherapy. The need for radiotherapy after local excision for small intraductal (ductal carcinoma in situ) cancers is being addressed in ongoing trials.

Primary therapy for limited breast cancer. Radiation therapy techniques

Available data show that breast conserving surgery followed by radiation therapy results in freedom of breast cancer recurrence rates that range from 86% at 10 years to 80% at 20 years for Stage I and II carcinoma. Breast cancer recurrence may be reduced further by the administration of systemic chemotherapy. Mastectomy and breast conserving therapy give equal tumor control and survival, but the latter results in superior quality of life. To achieve the best tumor control with optimal cosmesis, certain generally accepted principles of surgical and radiotherapeutic management need to be followed. The surgeon must use a neat technique that avoids excessive removal of breast and axillary tissue, improper placement of the surgical scar in the breast, and the formation of seromas or hematomas, which result in breast or arm edema. The radiation oncologist must use supervoltage energy, fields that avoid excessive irradiation of the lungs and other sensitive structures, proper field matching, whole breast doses ranging from 4500 to 5000 cGy with fractions of 180 to 200 cGy per day, and brachytherapy or electron beam boost to achieve a total dose of approximately 6000 cGy in the tumor area. These principles should result in good to excellent cosmesis in more than 80% of treated breasts. Breast conserving management offers women an incentive to achieve early detection. Early detection is the most promising approach to reduce mortality from breast cancer.

Tumor margin assessment as a guide to optimal conservation surgery and irradiation in early stage breast carcinoma

Between 1982 and 1985, 108 women with AJC Stage I and II invasive mammary carcinoma were treated to 115 breasts with conservative surgery and irradiation. The irradiation dose was adjusted to the histopathological normal tissue margin around the carcinoma in the tumor excision specimens. Margins were arbitrarily determined negative, close, and positive with normal tissue margins in the inked tumor excision specimens of greater than 5 mm, 2-5 mm, and less than 2 mm, respectively. Negative, close, and positive tumor margin patients were treated to radiation doses of 60, 65, and 70 Gy, respectively. The boost in excess of 50 Gy was directed to the tumor bearing quadrant of the breast using interstitial Ir-192 implants for doses greater than or equal to 70 Gy. The draining lymphatics were irradiated to 50 Gy except in patients with tumor in the lateral half of the breast and no axillary lymph node metastases. Histopathological evaluation of re-excision specimens revealed the difficulty of obtaining negative margins for tumors greater than 2 cm. By our criteria, 54% of the patients had a positive resection margin. None of the patients experienced a local recurrence at 60 months median follow-up. Three patients failed regionally, two in un-irradiated lymph node areas, one in the skin of the contralateral breast; five patients failed systemically. Overall and disease-free survival for Stages T1/N0, T1/N1, T2/N0 was 100 and 95%, respectively, and for T2/N1, 90 and 80%, respectively. The cosmesis was excellent in 66% of the patients with minimal treatment related complications. Carefully planned standardized irradiation with assessment of resection margins yields both excellent local control rates and cosmetic results.