Postmastectomy radiotherapy: will the selective use of postmastectomy radiotherapy study end the debate?

Postmastectomy radiotherapy: a review

PURPOSE OF REVIEW

We review the role of postmastectomy radiotherapy (PMRT) in the management of patients with early breast cancer.

RECENT FINDINGS

PMRT in patients with 4 or more involved axillary lymph nodes is the current standard of care but the indications for PMRT in patients with 1-3 involved nodes remain controversial. The Early Breast Cancer Trialists' Collaborative Group meta-analysis of randomised trials of PMRT provides the most comprehensive level 1 evidence base. However, its applicability in contemporary practice in the context of recent multidisciplinary advances in surgery, radiation therapy and systemic therapy remains challenging.

SUMMARY

The lack of consensus on the indications for PMRT in patients with 1-3 positive nodes underpins the variations in the national and international guidelines on PMRT. We emphasise the need for contemporary randomised trial data, and the potential to refine patient selection for PMRT using novel biomarkers of recurrence and radiosensitivity.

Postmastectomy radiotherapy for all node positive patients: The case against

Postmastectomy radiotherapy (PMRT) is accepted as the standard of care for women with early breast cancer with 4 or more involved axillary nodes. However the role of PMRT in women with 1-3 involved nodes remains controversial and guidelines vary. We present the arguments against advocating postmastectomy radiotherapy for all women with node positive breast cancer.

DEGRO practical guidelines for radiotherapy of breast cancer IV: radiotherapy following mastectomy for invasive breast cancer

BACKGROUND AND PURPOSE

Since the last recommendations from the Breast Cancer Expert Panel of the German Society for Radiation Oncology (DEGRO) in 2008, evidence for the effectiveness of postmastectomy radiotherapy (PMRT) has grown. This growth is based on updates of the national S3 and international guidelines, as well as on new data and meta-analyses. New aspects were considered when updating the DEGRO recommendations.

METHODS

The authors performed a comprehensive survey of the literature. Data from recently published (meta-)analyses, randomized clinical trials and international cancer societies' guidelines yielding new aspects compared to 2008 were reviewed and discussed. New aspects were included in the current guidelines. Specific issues relating to particular PMRT constellations, such as the presence of risk factors (lymphovascular invasion, blood vessel invasion, positive lymph node ratio >20 %, resection margins <3 mm, G3 grading, young age/premenopausal status, extracapsular invasion, negative hormone receptor status, invasive lobular cancer, size >2 cm or a combination of ≥ 2 risk factors) and 1-3 positive lymph nodes are emphasized.

RESULTS

The evidence for improved overall survival and local control following PMRT for T4 tumors, positive resection margins, >3 positive lymph nodes and in T3 N0 patients with risk factors such as lymphovascular invasion, G3 grading, close margins, and young age has increased. Recently identified risk factors such as invasive lobular subtype and negative hormone receptor status were included. For patients with 1-3 positive lymph nodes, the recommendation for PMRT has reached the 1a level of evidence.

CONCLUSION

PMRT is mandatory in patients with T4 tumors and/or positive lymph nodes and/or positive resection margins. PMRT should be strongly considered in patients with T3 N0 tumors and risk factors, particularly when two or more risk factors are present.

Radiotherapy issues in elderly breast cancer patients

Breast cancer in the elderly is a rising health care challenge. Under-treatment is common. While the proportion of older patients receiving adjuvant radiotherapy (RT) is rising, the proportion undergoing breast-conserving surgery without irradiation has also risen. The evidence base for loco-regional treatment is limited, reflecting the historical exclusion of older patients from randomised trials. The 2011 Oxford overview shows that the risk of first recurrence is halved in all age groups by adjuvant RT after breast-conserving surgery, although the absolute benefit in older 'low-risk' patients is small. There is level 1 evidence that a breast boost after breast-conserving surgery and whole-breast irradiation reduces local recurrence in older as in younger women, although in the former the absolute reduction is modest. Partial breast irradiation (external beam or intraoperative or postoperative brachytherapy) is potentially an attractive option for older patients, but the evidence base is insufficient to recommend it routinely. Similarly, shortened (hypofractionated) dose fraction schedules may be more convenient for older patients and are supported by level 1 evidence. There remains uncertainty about whether there is a subgroup of older low-risk patients in whom postoperative RT can be omitted after breast-conserving surgery. Biomarkers of 'low risk' are needed to refine the selection of patients for the omission of adjuvant RT. The role of postmastectomy irradiation is well established for 'high-risk' patients but uncertain in the intermediate-risk category of patients with 1-3 involved axillary nodes or node-negative patients with other risk factors where its role is investigational.

Management of early invasive breast cancer in very young women (<35 years)

BACKGROUND

To give an overview about current treatment recommendations and special problems concerning the management of women <35 years with early breast cancer.

METHODS

We performed a selective systematic literature review. We discussed with reference to key studies and meta-analyses, current standards of care, and controversies regarding patient management.

RESULTS

Breast cancer in patients younger than 35 years is rare but associated with an unsatisfactory prognosis. Local treatment should not differ from general guidelines, but awareness of the high risk of local recurrence must be maintained. Adjuvant polychemotherapy is almost always indicated, standard endocrine therapy is tamoxifen. Before the start of systemic therapy, the patient must be offered different types of fertility preservation. Pregnancy related breast cancer is not associated with a worse prognosis, but with delayed diagnosis. Therefore, every suspicious lesion in the breast or axilla must be imaged and biopsied. The optimal time to delay pregnancy following the diagnosis is unknown. Hormonal contraceptives are contraindicated after breast cancer. Every woman <35 years diagnosed with breast cancer should be offered genetic counseling.

CONCLUSION

The management of breast cancer in very young women requires a multidisciplinary team to find the optimal treatment and to solve their specific problems.

Postmastectomy irradiation in breast in breast cancer patients with T1-2 and 1-3 positive axillary lymph nodes: is there a role for radiation therapy?

Background

We aimed to evaluate retrospectively the correlation of loco-regional relapse (LRR) rate, distant metastasis (DM) rate, disease free survival (DFS) and overall survival (OS) in a group of breast cancer (BC) patients who are at intermediate risk for LRR (T1-2 tumor and 1-3 positive axillary nodes) treated with or without postmastectomy radiotherapy (PMRT) following modified radical mastectomy (MRM).

Methods

Ninety patients, with T1-T2 tumor, and 1-3 positive nodes who had undergone MRM received adjuvant systemic therapy with (n = 66) or without (n = 24) PMRT. Patient-related characteristics (age, menopausal status, pathological stage/tumor size, tumor location, histology, estrogen/progesterone receptor status, histological grade, nuclear grade, extracapsular extension, lymphatic, vascular and perineural invasion and ratio of involved nodes/dissected nodes) and treatment-related factors (PMRT, chemotherapy and hormonal therapy) were evaluated in terms of LRR and DM rate. The 5-year Kaplan-Meier DFS and OS rates were analysed.

Results

Differences between RT and no-RT groups were statistically significant for all comparisons in favor of RT group except OS: LRR rate (3%vs 17%, p = 0.038), DM rate (12% vs 42%, p = 0.004), 5 year DFS (82.4% vs 52.4%, p = 0.034), 5 year OS (90,2% vs 61,9%, p = 0.087). In multivariate analysis DM and lymphatic invasion were independent poor prognostic factors for OS.

Conclusion

PMRT for T1-2, N1-3 positive BC patients has to be reconsidered according to the prognostic factors and the decision has to be made individually with the consideration of long-term morbidity and with the patient approval.