A positive margin is not always an indication for radiotherapy after mastectomy in early breast cancer.
ABSTRACT Postoperative radiotherapy is frequently employed among breast cancer patients with positive surgical margins after mastectomy but there is little evidence to support this practice. This study examined relapse and survival among women with node-negative breast cancer and positive surgical margins after mastectomy.
Among 2570 women diagnosed between 1989 and 1998 and referred to the British Columbia Cancer Agency with pathologic (p)T1-2, pN0 invasive breast cancer treated with mastectomy, 94 had positive surgical margins and formed the study cohort. Women with more established indications for postmastectomy radiotherapy (PMRT) including T3-4 tumors or node-positive disease were excluded. Demographic, tumor, and treatment factors; relapse patterns; and Kaplan-Meier 8-year locoregional relapse-free, breast cancer-specific, and overall survival rates were compared between women who were treated with (n = 41) and without (n = 53) PMRT.
Median follow-up time was 7.7 years. The distributions of age, histologic grade, lymphovascular invasion (LVI), estrogen receptor status, and number of axillary nodes removed were similar between the two treatment groups. Six local chest wall recurrences (6.4%), 4 regional recurrences (4.3%), and 11 distant recurrences (11.7%) were identified. Local relapse rates were 2.4% vs. 9.4% (p = 0.23), and regional relapse rates were 2.4% vs. 5.7% (p = 0.63), with and without PMRT, respectively. Trends for higher cumulative locoregional relapse (LRR) rates without PMRT were identified in the presence of age <==50 years (LRR 20% without vs. 0% with PMRT), T2 tumor size (19.2% vs. 6.9%), grade III disease (23.1% vs. 6.7%), and LVI (16.7% vs. 9.1%). Statistical significance was not demonstrated in these differences (p > 0.10), possibly because of the small number of events. In patients with age >50 years, T1 tumors, grade I/II disease, and absence of LVI, no locoregional relapse occurred even with positive margins. PMRT did not improve distant relapse, 8-year breast cancer-specific and overall survival rates.
This study suggests that not all patients with node-negative breast cancer with positive margins after mastectomy require radiotherapy. Locoregional failure rates approximating 20% were observed in women with positive margins plus at least one of the following factors: age <==50 years, T2 tumor size, grade III histology, or LVI. The absolute and relative improvements in locoregional control with radiotherapy in these situations support the judicious, but not routine, use of PMRT for positive margins after mastectomy in patients with node-negative breast cancer.
[show abstract] [hide abstract]
ABSTRACT: Radiation therapy plays a critical role in the management of breast cancer and often is unavailable to patients in low- and middle-income countries (LMCs). There is a need to provide appropriate equipment and to improve the techniques of administration, quality assurance, and use of resources for radiation therapy in LMCs. Although the linear accelerator is the preferred equipment, telecobalt machines may be considered as an acceptable alternative in LMCs. Applying safe and effective treatment also requires well trained staff, support systems, geographic accessibility, and the initiation and completion of treatment without undue delay. In early-stage breast cancer, standard treatment includes the irradiation of the entire breast with an additional boost to the tumor site and should be delivered after treatment planning with at least 2-dimensional imaging. Although postmastectomy radiation therapy (PMRT) has demonstrated local control and overall survival advantages in all patients with axillary lymph node metastases, preference in limited resource settings could be reserved for patients who have >or=4 positive lymph nodes. The long-term risks of cardiac morbidity and mortality require special attention to the volume of heart and lungs exposed. Alternative treatment schedules like hypofractionated radiation and partial breast irradiation currently are investigational. Radiation therapy is an integral component for patients with locally advanced breast cancer after initial systemic treatment and surgery. For patients with distant metastases, radiation is an effective tool for palliation, especially for bone, brain, and soft tissue metastases. The implementation of quality-assurance programs applied to equipment, the planning process, and radiation treatment delivery must be instituted in all radiation therapy centers.Cancer 10/2008; 113(8 Suppl):2305-14. · 4.77 Impact Factor
[show abstract] [hide abstract]
ABSTRACT: Over the past 50 years breast cancer has become a major health problem affecting as many as one in eight women during their lifetime. Mastectomy is one of the main options in the treatment of breast cancer patients in an aim to avoid metastases of the disease. Yet, a successful operation does not eliminate the risks of local recurrence. Postmastectomy radiotherapy can significantly reduce these risks. This study intends to review and evaluate the challenges and complications which are sometimes associated with postmastectomy radiotherapy. Clinical and dosimetric trials were carried out using various techniques to optimize the treatments by maximizing the dose to the tumor and minimizing it to the healthy tissues at proximity. No one technique studied fulfilled these requirements. This is basically because the heterogeneity of the breast cancer means that the response to therapy and a systematic approach to treatment cannot be derived and treatment regions must be determined on a patient-by-patient basis. The accuracy of dose distributions is crucial to the quality of treatment planning and consequently to the doses delivered to patients undergoing radiation therapy. The successful radiation therapy depends on the stage of cancer.Journal of Science and Technology. 06/2011; 12(1):123-135.
Article: Post-mastectomy radiotherapy.[show abstract] [hide abstract]
ABSTRACT: Between 1997 and 1999, three studies re-ignited the debate on post-mastectomy radiation therapy (PMRT). Despite 20 years of follow-up and multiple re-analyses, the results of these studies still generate vigorous debate among the learned men and women who care for breast cancer patients. In honor of the 10th anniversary of the Danish Breast Cancer Cooperative Group Post-Mastectomy trial 82c publication, the following review offers the reader a brief history of the controversies that preceded and followed these publications. Other related controversies, PMRT in the setting of neo-adjuvant chemotherapy, positive margins or T3N0 primary tumors, as well as internal mammary lymph node irradiation, are also presented. Finally, we present a brief discussion about the toxicities associated with PMRT. This review will familiarize the reader with often discussed/debated issues concerning PMRT and prepare them to enter the debate.Clinical advances in hematology & oncology: H&O 08/2009; 7(8):533-43.