10-Year results after sector resection with or without postoperative radiotherapy for stage I breast cancer: a randomized trial

Consequences of axillary recurrence after conservative breast surgery

BACKGROUND

The aim was to study the incidence, time course and prognosis of patients who developed axillary recurrence after breast-conserving surgery, and to evaluate possible risk factors for axillary recurrence and prognostic factors after axillary recurrence.

METHODS

In a population-based cohort of 6613 women with invasive breast cancer who had breast-conserving surgery between 1981 and 1990, 92 recurrences in the ipsilateral axilla were identified. Risk factors for axillary recurrence were studied in a case-control study nested in the cohort, and late survival was documented in the women with axillary recurrence.

RESULTS

The overall risk of axillary recurrence was 1.0 per cent at 5 years and 1.7 per cent at 10 years. The risk of axillary recurrence increased with tumour size (P = 0.033) and was highest in younger women (odds ratio (OR) 3.9 for women aged less than 40 years compared with those aged 50-59 years). Radiotherapy to the breast reduced the risk of axillary recurrence (OR 0.1 (95 per cent confidence interval 0.1 to 0.4)). The breast cancer-specific survival rate after axillary recurrence, as measured from primary treatment, was 78.0 per cent at 5 years and 52.3 per cent at 10 years. Tumour size and node status had a statistically significant effect on death from breast cancer.

CONCLUSION

Axillary recurrence is rare, although more common in younger women with large tumours. Radiotherapy to the breast was protective. Tumour size and node status were the most important prognostic factors in women with axillary recurrence.

Is radiotherapy needed after breast conservation for small invasive breast cancers?

AIMS

The purpose of this study was to determine the rate of local recurrence in patients with small invasive breast cancers (<1 cm) who had been treated with breast-conserving surgery either with (group 1) or without (group 2) adjuvant radiotherapy.

METHODS

This is a retrospective study of 110 patients with an invasive breast cancer less than 1 cm in size, treated in our centre by breast-conserving surgery. Parameters examined included age at and mode of presentation, histopathological features, adjuvant therapy, length of follow-up and outcome in terms of local recurrence rate and death.

RESULTS

In group 1 there were 59 women of median age 57 (38-80) years. The median tumour size was 9 (1-10) mm and median follow-up was 74 (15-110) months. There were no local recurrences. In group 2 the median age at presentation was 59 (48-81) years. The median tumour size was 7 (2-10) mm and median follow-up was 47 (14-93) months. There were three non-breast-cancer related deaths and three local recurrences (6%).

CONCLUSIONS

A local recurrence rate of 6% at almost 4 years median follow-up suggests that it may be possible to avoid adjuvant radiotherapy in a subgroup of largely screen-detected, node-negative patients with invasive tumours less than 1 cm, in whom adequate local excision is performed. Further follow-up is required to substantiate this.

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.

Contemporary management of breast cancer

Breast cancer is a heterogenous disease with significant variations in biologic potential, ranging from small, low-grade, DCIS discovered mammographically with essentially no impact on patient survival to rapidly growing, palpable, locally advanced invasive breast cancer with clinically palpable nodal metastasis. The current challenge is to identify the clinical, pathologic, and molecular factors that determine the biologic potential of a particular breast cancer. Although size, nodal status, histologic grade, age, surgical margin, and hormone receptor status of breast cancer are the most important prognostic factors, the focus of research must be beyond these factors to other nonspecific prognostic information. Bone marrow micrometastasis may be an important factor to help predict outcome (7a) and the complement of sentinel node biopsy, bone marrow analysis, and primary tumor features may allow physicians to better select therapy. With increased understanding of the individual molecular events that control the invasive potential of a particular cancer, practitioners should be better able to predict more accurately which patients have little risk of recurrent disease or metastasis and would be best served by surgery alone versus patients who have a high risk of recurrent and metastatic disease and who should receive multimodality care.

Modern radiotherapy for modern surgeons: an update on radiation oncology

Changes in the practice of radiation oncology have been significant over the last decade and continue to develop at an exciting rate. These advances range from our understanding of the increasingly important role of radiotherapy in the adjuvant and definitive settings to huge technological progress in the areas of tumour delineation, treatment planning, delivery and verification. In many cases, benefits have resulted from the ability of modern radiotherapy to deliver high doses with great accuracy and increasing safety in a highly individualized manner. This has impacted favourably on the management of all major malignancies as discussed in this paper. A good understanding of what can be achieved with modern radiotherapy has never been more important in ensuring an effective multidisciplinary approach to cancer management.

Accelerated partial breast irradiation

Logistical barriers of time and travel created by the conventional six week course of radiotherapy prevent many women from pursuing breast conservation treatment. For the past 12 years, Accelerated Partial Breast Irradiation (APBI) has been investigated as a potential alternative treatment approach in women with early stage breast cancer. The ability to complete treatment in five days has the potential to provide additional women with the option of breast conservation. The validity of this APBI is supported in the study of in-breast recurrence patterns, pathologic data and the clinical treatment experience. The review of the recent data on contemporary APBI reveals that patient selection criteria and brachytherapy quality assurance are clearly critical components and necessary to assure a successful treatment outcome. This updated report from the American Brachytherapy Society on Accelerated Partial Breast Irradiation reviews the appropriate background data supporting this treatment approach with conclusions regarding patient selection criteria and treatment delivery.

What is the evidence for a reduced risk of local recurrence with age among older patients treated by breast conserving therapy?

With the rising age of the population and the proposed extension of the breast screening programme to older women, increasing numbers of older patients are becoming eligible for breast conserving surgery and post-operative breast irradiation. Women over the age of 70 have traditionally been omitted from randomized controlled trials for assessing the role of breast radiotherapy after local surgery. The majority of trials suggest that local recurrence rates do decline with age. Similar conclusions are suggested by many non-randomized studies. Comparison of randomized and non-randomized studies is limited by differing extent of classifying tumour margins, nodal status, use of adjuvant systemic therapy, sample size, analytical approaches and duration of follow-up. Large randomized trials in older women are needed to assess whether, with careful attention to obtaining clear tumour margins, radiotherapy is required in low risk, ER positive, node negative breast cancer patients following wide excision and adjuvant tamoxifen. Within both randomized and non-randomized studies, only a few studies have failed to demonstrate an impact of age on recurrence rates following breast conserving treatment, with the majority finding a reduction in local recurrence rates with increasing age. Importantly for interpretation, no studies suggest that recurrence rates increase with age. The variation in analytical approaches and sample sizes are such that the variety of conclusions is not surprising. The results are compatible with a tendency for local recurrence rates to fall with age, but the variability is such that one cannot quantify this change with any precision.

Contralateral breast cancer risk

The use of breast-conserving treatment approaches for breast cancer has now become a standard option for early stage disease. Numerous randomized studies have shown medical equivalence when mastectomy is compared to lumpectomy followed by radiotherapy for the local management of this common problem. With an increased emphasis on patient involvement in the therapeutic decision making process, it is important to identify and quantify any unforeseen risks of the conservation approach. One concern that has been raised is the question of radiation- related contralateral breast cancer after breast radiotherapy. Although most studies do not show statistically significant evidence that patients treated with breast radiotherapy are at increased risk of developing contralateral breast cancer when compared to control groups treated with mastectomy alone, there are clear data showing the amount of scattered radiation absorbed by the contralateral breast during a routine course of breast radiotherapy is considerable (several Gy) and is therefore within the range where one might be concerned about radiogenic contralateral tumors. While radiation related risks of contralateral breast cancer appear to be small enough to be statistically insignificant for the majority of patients, there may exist a smaller subset which, for genetic or environmental reasons, is at special risk for scatter related second tumors. If such a group could be predicted, it would seem appropriate to offer either special counseling or special prevention procedures aimed at mitigating this second tumor risk. The use of genetic testing, detailed analysis of breast cancer family history, and the identification of patients who acquired their first breast cancer at a very early age may all be candidate screening procedures useful in identifying such at- risk groups. Since some risk mitigation strategies are convenient and easy to utilize, it makes sense to follow the classic 'ALARA' (as low as reasonably achievable) principles and to minimize scattered radiation for these special risk groups and perhaps for all patients undergoing breast radiotherapy. This paper reviews the literature on the risk of radiation- related second contralateral breast cancers.

Time trends in the results of breast conservation in 4694 women

In a population-based cohort of 4694 women with invasive breast cancer, operated upon with breast conserving surgery (BCS) in 1981--1990 and followed through to 1997, we studied how this technique had been adopted into clinical practice, especially with reference to the use of radiotherapy (RT). Our main aim was to see whether there was a drift in the risk of local recurrence and breast cancer death over time. During the 30,151 person-years of observation in the cohort, there were 582 local recurrences, 456 breast cancer deaths and 438 deaths due to other causes. Postoperative RT was given to 70.2%, but usage increased over the period. The women not receiving RT were mostly elderly, but also in women <70 years, 20.4% did not receive RT. The risk for local recurrence after RT were 7.6 and 17.8% at 5 and 10 years, respectively. Without RT, more than 30% had a local recurrence at 10 years. Thus, the choice not to irradiate failed to target women at a low risk. In a multivariate Cox analysis taking tumour size, nodal status, age at operation and RT into account, there was a trend for a higher risk of local recurrence in the later time period, relative hazard 1.5 (95% confidence interval (CI) 1.0--2.1). Corrected survival was 93.3 and 85.2% at 5 and 10 years, respectively.

Radiotherapy after breast-conserving surgery in small breast carcinoma: long-term results of a randomized trial

BACKGROUND

Breast-conserving surgery followed by radiotherapy is a widely accepted form of treatment in patients with breast cancer of limited extent. Many attempts have been made to identify subgroups of patients who might avoid radiotherapy.

PATIENTS AND METHODS

Between 1987 and 1989, 579 women with carcinoma of the breast were randomly assigned to quadrantectomy, axillary dissection and radiotherapy (299) and to quadrantectomy with axillary dissection without radiotherapy (280). Eligible patients were women with a breast carcinoma less than 2.5 cm in maximum diameter up to 70 years of age. Primary endpoints were intra-breast tumour reappearance (IBTR) and all-cause mortality.

RESULTS

The number of IBTRs was significantly higher in patients treated with surgery alone (59 cases out of 273; 10-year crude cumulative incidence of 23.5%) than in patients treated with surgery plus radiotherapy (16 cases out of 294; 10-year crude cumulative incidence of 5.8%). The difference in IBTR frequency between the two treatments appeared to be particularly high in women up to 45 years of age, tending to decrease with increasing age up to no apparent difference in women older than 65 years. Overall survival curves for the two groups, did not differ significantly (P = 0.326). However, a limited survival advantage was evident after radiotherapy for node-positive women.

CONCLUSIONS

After breast-conserving surgery radiotherapy appears indicated in all patients up to 55 years of age, in patients with positive axillary nodes, and in patients with extensive intraductal component at histology. The data suggest that radiotherapy may be avoided in patients older than 65, and may be optional in women aged 56-65 years with negative nodes.

Breast conservation therapy with tumor bed irradiation alone in a selected group of patients with stage I breast cancer

Radiotherapy after breast-conserving surgery increases local control. We tested the feasibility of limited surgery with tumor bed irradiation only with 192Ir in a selected group of patients with stage I breast cancer. Twenty-five breasts in 24 women more than 60 years old with low- or intermediate-grade stage I tumors were treated with placement of interstitial catheters at the time of lumpectomy and axillary node dissection. This procedure was followed by after-loading with low-dose 192Ir to deliver 20-25 Gy to the tumor bed over 24-48 hours. There were neither local recurrences in the breast nor distant recurrences at a median follow-up of 47 months (range 25-90 months). Cosmetic appearance ranged from very good to excellent. There were no long-term complications. It is feasible to treat a select group of patients with tumor bed irradiation, using relatively low doses of interstitial irradiation, with excellent local control and no significant morbidity.

Breast carcinomas of limited extent: frequency, radiologic-pathologic characteristics, and surgical margin requirements

BACKGROUND

Clinical trials established the value of breast-conserving treatment (BCT) including the macroscopic removal of the tumor followed by local radiation therapy (RT) for Stage I and II invasive carcinomas. The occurrence of local tumor recurrence is related to the extent and multifocality of the tumor. Various studies aim to identify those tumors that could be proper candidates for conventional BCT. Furthermore, recent studies have focused on the identification of tumors that may be treated by breast-conserving surgery alone without RT. Small, localized tumors theoretically should be the potential candidates for this type of treatment. The mammographic and pathologic criteria for the identification of tumors with limited extent are not yet established; furthermore, the optimal extent of the surgical excision and the method for margin examination are controversial.

METHODS

Surgical breast-conserving procedures were simulated in a review of 135 mastectomy specimens of patients treated for an invasive carcinoma (> or = 4 cm in size, all pathologic types except invasive lobular carcinoma) who were theoretically eligible for conservative treatment. Tumor spread including possible multifocality and multicentricity was studied by the technique of correlated specimen radiography and pathology. Breast carcinoma of limited extent (BCLE), the proper tumor profile for BCT, was defined as having no invasive carcinoma, ductal carcinoma in situ, and lymphatic emboli foci beyond 1 cm from the edge of the dominant mass.

RESULTS

Fifty-three percent of the patients in this series had a BCLE. No statistically significant relation was found between BCLE and patient age, pathologic size, type and grade of the tumor, lymph node status, mode of detection, and mammographic aspect of the index tumor. Based on mammography, the absence of calcification or tumor density beyond the edge of index tumor appears to be the best predictor for BCLE (P < 0.0001). A 1-cm microscopically tumor free margin as the outer rim of a macroscopic surgical margin of 2 cm gives the best positive predictive value based on pathology (P < 0.0001). By applying the above conditions, 72 of the 135 cancers were identified as being potential BCLE cases in this series. However, whereas 64 of these 72 tumors (89%) were correctly identified as being true BCLE, 8 (11%) were erroneously identified as such (non-BCLE cases), having "residual" tumor foci beyond 2 cm from the edge of the dominant tumor.

CONCLUSIONS

We conclude, that approximately 50% of invasive ductal carcinomas may have limited extent. The accuracy of identifying this group of cancers, the proper candidates for BCT, by applying state-of-the-art mammography and pathology may be as high as 90%. A subset of these tumors might represent the potential candidates for treatment with surgery alone without RT. As a result, the routine application of BCT complemented by RT would have led to the overtreatment of 89% of the patients with a BCLE in this series; conversely, 11% of the tumors may have recurred without the use of RT. Considering that these conclusions are based on a theoretic morphologic model, further clinical studies with facilities for high quality team approach in diagnosis and therapy are needed to evaluate the impact of BCLE on BCT strategies. The results of this study should not justify the withholding of RT outside the context of clinical trials.

Lumpectomy with or without postoperative radiotherapy for breast cancer with favourable prognostic features: results of a randomized study

The aim of this trial was to study the value of adding post-operative radiotherapy to lumpectomy in a subgroup of breast cancer patients with favourable patient-, tumour-, and treatment-related prognostic features. 152 women aged over 40 with unifocal breast cancer seen in preoperative mammography were randomly assigned to lumpectomy alone (no-XRT group) or to lumpectomy followed by radiotherapy to the ipsilateral breast (50 Gy given within 5 weeks, XRT group). All cancers were required to be invasive node-negative, smaller than 2 cm in diameter and well or moderately differentiated, to contain no extensive intraductal component, to be progesterone receptor-positive, DNA diploid, have S-phase fraction </=7 and be excised with at least 1 cm margin. During a mean follow-up time of 6.7 years, 13 (18.1%) cancers recurred locally in the no-XRT and 6 (7.5%) in the XRT group (P = 0.03). There was no difference between the groups in the ultimate breast preservation rate (95.0% vs. 94.4% in XRT and no-XRT, respectively, P = 0.88), distant metastasis-free survival (P = 0.36), or 5-year cancer-specific survival (97.1% in XRT and 98.6 in no-XRT). Radiation therapy given after lumpectomy reduces the frequency of ipsilateral breast recurrences even in women with small breast cancer with several favourable clinical and biological features. However, the breast preservation rate may not increase due to more frequent use of salvage mastectomies in patients treated with postoperative radiotherapy.