Locoregional Recurrence After Sentinel Lymph Node Dissection
Locoregional Recurrence After Sentinel Lymph Node Dissection
Background and Objective: Sentinel lymph node dissection (SLND) has eliminated the need for axillary dissection (ALND) in patients whose sentinel node (SN) is tumor-free. However, completion ALND for patients with tumor-involved SNs remains the standard to achieve locoregional control. Few studies have examined the outcome of patients who do not undergo ALND for positive SNs. We now report local and regional recurrence information from the American College of Surgeons Oncology Group Z0011 trial.
Methods: American College of Surgeons Oncology Group Z0011 was a prospective trial examining survival of patients with SN metastases detected by standard H and E, who were randomized to undergo ALND after SLND versus SLND alone without specific axillary treatment. Locoregional recurrence was evaluated.
Results: There were 446 patients randomized to SLND alone and 445 to SLND + ALND. Patients in the 2 groups were similar with respect to age, Bloom-Richardson score, estrogen receptor status, use of adjuvant systemic therapy, tumor type, T stage, and tumor size. Patients randomized to SLND + ALND had a median of 17 axillary nodes removed compared with a median of only 2 SN removed with SLND alone (P < 0.001). ALND also removed more positive lymph nodes (P < 0.001). At a median follow-up time of 6.3 years, there were no statistically significant differences in local recurrence (P = 0.11) or regional recurrence (P = 0.45) between the 2 groups.
Conclusions: Despite the potential for residual axillary disease after SLND, SLND without ALND can offer excellent regional control and may be reasonable management for selected patients with early-stage breast cancer treated with breast-conserving therapy and adjuvant systemic therapy.
Sentinel lymph node dissection (SLND) has revolutionized the management of clinically node-negative women with breast cancer. Single institutional studies, multi-institutional studies, and prospective randomized trials have shown the safety of omitting axillary lymph node dissection (ALND) for women whose sentinel node (SN) is free of metastatic disease. The recommended management, however, of the patient with SN metastases has continued to be completion ALND. ALND is advised because of its excellent regional control and potential impact on survival. Completion ALND for women with micrometastases or isolated tumor cells (ITCs) is especially controversial because of the uncertain clinical significance of micrometastases and the low yield of additional positive axillary lymph nodes. However, most consensus statements including one from the American Society of Clinical Oncology recommend ALND for patients whose SN contains macrometastases, ITCs, or micrometastases.
A number of reports have suggested that selected patients with SN metastasis may be managed without completion ALND. However, most of these reports are small, single-institutional studies evaluating patients whose SN demonstrated primarily micrometastases or ITCs. The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial entitled "A randomized trial of axillary node dissection in women with clinical T1 or T2 N0 M0 breast cancer who have a positive sentinel node" was designed to compare outcomes of patients whose hematoxylin and eosin (H and E)-detected SN metastases were treated with completion ALND or managed without completion ALND and without third field axillary radiation. The primary end point of the study was overall survival. Although locoregional recurrence was not a prespecified secondary end point, the study did have a prespecified plan for monitoring regional recurrence, reflecting concern that regional recurrence rate might be unacceptably high without completion ALND. Thus, locoregional control was assessed to determine the effect of ALND and SLND in contemporary women managed with breast-conserving surgery, adjuvant systemic therapy, and opposing tangential field whole breast irradiation. The locoregional recurrence rates seen in this study and the effect of the extent of operation on locoregional control provide important information regarding the management of the axilla for patients with early breast cancer.
Abstract and Introduction
Abstract
Background and Objective: Sentinel lymph node dissection (SLND) has eliminated the need for axillary dissection (ALND) in patients whose sentinel node (SN) is tumor-free. However, completion ALND for patients with tumor-involved SNs remains the standard to achieve locoregional control. Few studies have examined the outcome of patients who do not undergo ALND for positive SNs. We now report local and regional recurrence information from the American College of Surgeons Oncology Group Z0011 trial.
Methods: American College of Surgeons Oncology Group Z0011 was a prospective trial examining survival of patients with SN metastases detected by standard H and E, who were randomized to undergo ALND after SLND versus SLND alone without specific axillary treatment. Locoregional recurrence was evaluated.
Results: There were 446 patients randomized to SLND alone and 445 to SLND + ALND. Patients in the 2 groups were similar with respect to age, Bloom-Richardson score, estrogen receptor status, use of adjuvant systemic therapy, tumor type, T stage, and tumor size. Patients randomized to SLND + ALND had a median of 17 axillary nodes removed compared with a median of only 2 SN removed with SLND alone (P < 0.001). ALND also removed more positive lymph nodes (P < 0.001). At a median follow-up time of 6.3 years, there were no statistically significant differences in local recurrence (P = 0.11) or regional recurrence (P = 0.45) between the 2 groups.
Conclusions: Despite the potential for residual axillary disease after SLND, SLND without ALND can offer excellent regional control and may be reasonable management for selected patients with early-stage breast cancer treated with breast-conserving therapy and adjuvant systemic therapy.
Introduction
Sentinel lymph node dissection (SLND) has revolutionized the management of clinically node-negative women with breast cancer. Single institutional studies, multi-institutional studies, and prospective randomized trials have shown the safety of omitting axillary lymph node dissection (ALND) for women whose sentinel node (SN) is free of metastatic disease. The recommended management, however, of the patient with SN metastases has continued to be completion ALND. ALND is advised because of its excellent regional control and potential impact on survival. Completion ALND for women with micrometastases or isolated tumor cells (ITCs) is especially controversial because of the uncertain clinical significance of micrometastases and the low yield of additional positive axillary lymph nodes. However, most consensus statements including one from the American Society of Clinical Oncology recommend ALND for patients whose SN contains macrometastases, ITCs, or micrometastases.
A number of reports have suggested that selected patients with SN metastasis may be managed without completion ALND. However, most of these reports are small, single-institutional studies evaluating patients whose SN demonstrated primarily micrometastases or ITCs. The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial entitled "A randomized trial of axillary node dissection in women with clinical T1 or T2 N0 M0 breast cancer who have a positive sentinel node" was designed to compare outcomes of patients whose hematoxylin and eosin (H and E)-detected SN metastases were treated with completion ALND or managed without completion ALND and without third field axillary radiation. The primary end point of the study was overall survival. Although locoregional recurrence was not a prespecified secondary end point, the study did have a prespecified plan for monitoring regional recurrence, reflecting concern that regional recurrence rate might be unacceptably high without completion ALND. Thus, locoregional control was assessed to determine the effect of ALND and SLND in contemporary women managed with breast-conserving surgery, adjuvant systemic therapy, and opposing tangential field whole breast irradiation. The locoregional recurrence rates seen in this study and the effect of the extent of operation on locoregional control provide important information regarding the management of the axilla for patients with early breast cancer.