Adjuvant radiotherapy after breast conserving surgery for breast cancer. Pro

Saving the Breast Saves the Lives of Breast Cancer Patients

Introduction. Surgery has been known as the procedure of choice for breast cancer management since 1700 years before Christ. Nowadays, breast-conserving surgery and mastectomy are performed in selected cases with specific clinical criteria. Here, we compare these two procedures for breast cancer patients with variable features in Cancer Research Center, Tehran, as a single institution experience.

Morbidity after breast cancer treatment and physiotherapeutic performance

Breast cancer (BC) accounts for >30% of all new cancer patients among women but with increased early detection rates and improved adjuvant therapy, the 5-year survival rate presently reaches >85%. As the number of BC survivors increases, research into the sequelae of the cancer and its treatment on quality of life is a priority. Understanding the potential complications of treatment and developing effective rehabilitation techniques can reduce the impact of such effects on activities of daily life. The aim of this review is to discuss the major sequelae of treatment for BC, and the physiotherapist's role in the prevention and treatment of such complications. Breast cancer treatment can result in pulmonary and upper extremity morbidities that may manifest either early or late. Prevention and treatment of lymphoedema, scar adherence and pulmonary complications can be achieved. Additionally pain reduction and maintenance of range of movement, muscle strength and adequate posture are parts of physiotherapy, which is an important component in the rehabilitation of women with BC.

When May Adjuvant Radiotherapy be Avoided in Operable Breast Cancer?

Randomised trials in which the omission of radiotherapy has been tested after breast-conserving surgery, with or without adjuvant systemic therapy, show a significant four- to five-fold reduction in local recurrence. As yet, no subgroup of women managed by breast-conserving surgery has been identified from whom radiotherapy can be withheld. Few randomised data have been published on the effect of omission of radiotherapy on local control, quality of life and costs, particularly in older women for whom the risk of local recurrence is generally lower. Ongoing trials are evaluating the role of radiotherapy in this population of low risk, older women. Adjuvant radiotherapy after breast-conserving surgery or mastectomy significantly reduces the incidence of local recurrence. In women who have had a mastectomy at high risk of recurrence (> 20% risk of recurrence at 10 years), adjuvant radiotherapy improves survival if combined with adjuvant systemic therapy. Among women with T3 tumours, and those with four or more involved axillary nodes treated by mastectomy, postoperative radiotherapy is the standard of care. For women at intermediate risk of recurrence (i.e. <15% 10-year risk of recurrence after surgery and systemic therapy alone), with one to three involved nodes or node negative with other risk factors, the role of radiotherapy is unclear. Clinical trials to assess the role of postmastectomy radiotherapy (PMRT) in this setting are needed. For pT1-2, pNO tumours without other risk factors, there is no evidence at present that PMRT is needed.

Adjuvant radiotherapy after mastectomy for pT1-pT2 node negative (pN0) breast cancer: is it worth the effort?

PURPOSE

Postoperative radiotherapy (RT) for pT1-2 pN0 breast cancer was the standard treatment in our department. Since little data on the importance of RT in this subgroup are known, we reviewed the clinical records with regard to overall survival.

MATERIAL AND METHODS

From 1984 until 2000, 1789 files were submitted to retrospective analyses; 731 had a pT1 (n=427) or pT2 (n=304) pN0 lesion. They were treated with breast conserving surgery (BCS) (n=343) or mastectomy (ME) (n=388), axillary lymph node dissection (ALND) and post-operative RT. The outcome was analyzed and compared with the patients included in the SEER-Data 1988-1997 (NCI-Surveillance, Epidemiology and End Results, release 2000) that were treated according to the standard treatment: BCS+ALND+RT, or ME+ALND no RT.

RESULTS

The actuarial overall survival (OS) at 5 and 10 years after BCS was 93.3% and 85.1% for pT1 and 88.3% and 75.4% for pT2 tumors. These results are comparable with the SEER (93.9%, 84.9% for pT1, and 87.3%, 76.7% for pT2, respectively). For our ME patients the OS was 91.8% and 79.9%, respectively (pT1 at 5 and 10 years, respectively), and 83.6% and 70.4% (pT2 at 5 and 10 years). In the SEER data the analyses resulted in 89.3% and 73.8% (pT1), and 81.1% and 63.5% (pT2), respectively.

DISCUSSION

Although both databases are retrospective, the comparable survival in BCS patients pleads for the similarity of the two populations. The better OS observed in ME patients treated with RT compared to the SEER patients argues in favor of a benefit due to adjuvant radiotherapy.

CONCLUSION

Radiotherapy after mastectomy might improve survival in low-risk node negative patients. Our data shows an absolute benefit of between 2.5% and 6.9% OS in favor of post ME radiotherapy, compared to the SEER data.

Radiation therapy plus tamoxifen versus tamoxifen alone after breast-conserving surgery in postmenopausal women with stage I breast cancer: a decision analysis

PURPOSE

To compare outcomes for hypothetical cohorts of postmenopausal patients with estrogen receptor-positive tumors that are < or = 2 cm in size, with pathologically uninvolved axillary nodes, treated with radiation therapy plus tamoxifen versus tamoxifen alone after breast-conserving surgery.

METHODS

A Markov model was used to simulate patients' clinical course and estimate overall survival, recurrence-free survival, time with an intact breast, and death from breast cancer. Probabilities were derived from randomized trials and retrospective studies. Analyses were performed separately by age of diagnosis in 5-year increments from 50 to 80 years. Sensitivity analyses tested the stability of radiation benefit.

RESULTS

The modeled recurrence-free survival benefit of giving radiation therapy was 3.35 years for women who were 50 years of age at diagnosis, versus 0.61 years for women who were 80 years of age. In the 50-year-old cohort, radiation therapy resulted in additional 0.60 years survival, compared with 0.04 years among 80-year-olds. A 50-year-old woman who received radiation therapy plus tamoxifen was less likely to die from breast cancer than if she received tamoxifen alone (2.43% v 5.29%; relative-risk reduction, 54%). An 80-year-old woman had a 1.17% chance of dying from breast cancer if she received radiation therapy plus tamoxifen, versus 2.02% with tamoxifen alone (relative-risk reduction, 42%). Sensitivity analyses showed that the magnitude of benefit was strongly influenced by including unequal rates of developing distant disease after breast recurrence between the treatment arms and varying rates of local recurrence.

CONCLUSION

The absolute and relative benefits of radiation therapy and individual patient preferences for different health states should be considered when selecting treatment.

Current surgical management of breast cancer

Breast cancer surgery continues to become more conservative. Supporting this conservatism are (1) earlier diagnosis through mammographic screening, (2) an increasing role for diagnostic ultrasound and magnetic resonance imaging, (3) the further development of image-guided core-needle biopsy, and (4) the advent of sentinel lymph node biopsy as an alternative to conventional axillary dissection. For patients with duct carcinoma in situ, the addition of radiotherapy and tamoxifen to surgical excision reduces local recurrence but has not yet improved survival over the rate observed with excision alone. There may be low-risk subgroups of duct carcinoma in situ patients for whom conservative surgery alone is adequate treatment. For patients with invasive cancer, breast conservation remains underutilized. A small survival benefit from post-mastectomy adjuvant radiotherapy is offset by an increased incidence of cardiovascular mortality, a phenomenon which has not yet been demonstrated for radiotherapy following breast conservation. Sentinel lymph node biopsy represents a new standard of care for axillary lymph node staging in the large majority of breast cancer patients with high-risk duct carcinoma in situ and stage I-II invasive cancers. The procedure is feasible, accurate, and works best with a combination of blue dye and radioisotope mapping. After proper validation studies, patients with negative sentinel lymph nodes do not require axillary dissection. The prognostic significance of sentinel lymph node micrometastases identified by enhanced pathologic techniques remains a matter of debate. Prophylactic mastectomy reduces breast cancer incidence and mortality among those with a high-risk family history, and mutations of BRCA1-2, but has significant adverse psychosocial sequelae for a small and unpredictable fraction of patients and should not be undertaken lightly. Prophylactic oophorectomy should be offered to all women with BRCA1-2 mutations, especially those beyond the years of childbearing.