A 10-year follow-up of treatment outcomes in patients with early stage breast cancer and clinically negative axillary nodes treated with tangential breast irradiation following sentinel lymph node dissection or axillary clearance

Abstract

We compare long-term outcomes in patients with node negative early stage breast cancer treated with breast radiotherapy (RT) without the axillary RT field after sentinel lymph node dissection (SLND) or axillary lymph node dissection (ALND). We hypothesize that though tangential RT was delivered to the breast tissue, it at least partially sterilized occult axillary nodal metastases thus providing low nodal failure rates. Between 1995 and 2001, 265 patients with AJCC stages I–II breast cancer were treated with lumpectomy and either SLND (cohort SLND) or SLND and ALND (cohort ALND). Median follow-up was 9.9 years (range 8.3–15.3 years). RT was administered to the whole breast to the median dose of 48.2 Gy (range 46.0–50.4 Gy) plus boost without axillary RT. Chi-square tests were employed in comparing outcomes of two groups for axillary and supraclavicular failure rates, ipsilateral in-breast tumor recurrence (IBTR), distant metastases (DM), and chronic complications. Progression-free survival (PFS) was compared using log-rank test. There were 136/265 (51%) and 129/265 (49%) patients in the SLND and ALND cohorts, respectively. The median number of axillary lymph nodes assessed was 2 (range 1–5) in cohort SLND and 18 (range 7–36) in cohort ALND (P < 0.0001). Incidence of AFR and SFR in both cohorts was 0%. The rates of IBTR and DM in both cohorts were not significantly different. Median PFS in the SLND cohort is 14.6 years and 10-year PFS is 88.2%. Median PFS in the ALND group is 15.0 years and 10-year PFS is 85.7%. At a 10-year follow-up chronic lymphedema occurred in 5/108 (4.6%) and 40/115 (34.8%) in cohorts SLND and ALND, respectively (P = 0.0001). This study provides mature evidence that patients with negative nodes, treated with tangential breast RT and SLND alone, experience low AFR or SFR. Our findings, while awaiting mature long-term data from NSABP B-32, support that in patients with negative axillary nodal status such treatment provides excellent long-term cure rates while avoiding morbidities associated with ALND or addition of axillary RT field.

Arm Lymphedema as a Consequence of Breast Cancer Therapy

“…The vast majority of literature, with only a few negative studies, supports the fact that the modern 3-D tangential radiation port of the breast, administered in supine position, will at least partially irradiate the undissected axillary lymph nodes stations (Smitt et al, 1999;Takeda et al, 2000Takeda et al, , 2004Krasin et al, 2000;Aristei et al, 2001;Schlembach et al, 2001;Orecchia et al, 2005;Wong et al, 2008;Rabinovitch et al, 2008). This phenomenon may explain why even patients with SLND experience lymphedema as a long-term toxicity [Wernicke et al, 2010]. Fig.…”

“…All blue-stained nodes and/or nodes with radioactive counts, as measured with the gamma probe, are defined as sentinel lymph nodes. Typically, the number of nodes sample as a result of a SLND is small, with a median number of 2 nodes (Wernicke, 2010).…”

“…The patient selfassessment groups demonstrated the lymphedema in 10/111 (10.0%) of patients in the SLND cohort and 39/115 (33.9%) of women reporting this complication in the ALND group (p<0.0001). This difference appears to be sustainable even a decade after the surgery, and the percentage of patients that experienced chronic lymphedema is significantly greater in the ALND cohort as compared with the SLND one (Wernicke et al, 2010) [ Table 1]. …”

“…If a low incidence of ALN failures lies in sterilization of the occult metastases in the axillary lymph nodes with the conventional breast tangential ports delivering RT to a patient in a supine position (Wernicke et al, 2010), radiotherapy may be at least in part responsible for the morbidity attributable to surgery. Goodman et al reported that with the standard radiation tangents, 90% of the Berg level I axilla and up to 70% of level II axillary lymph nodes received 95% of the prescribed dose to the breast (Smitt et al, 1999).…”

Manual Lymphatic Drainage after Subepidermal Tracer Injection Optimizes Results of Sentinel Lymph Node Labeling in Primary Breast Cancer

“…Following the publication of the first large series on sentinel lymph node biopsy (SLNB) in the surgical staging of primary breast cancer, SLNB has found rapid and wide acceptance [3]. Lymph edema in patients undergoing SLNB only is rare [4]. …”