Whole breast radiotherapy in cN0 early breast cancer patients with pathological sentinel lymph nodes (pN1mic, pN1a) without axillary dissection: preliminary results of the observational LISEN trial

Abstract

Purpose Axillary management remains unclear when sentinel lymph node (SLN) results are positive in cN0 patients with breast cancer (BC). The trial ACOSOG Z0011 represented a revolution with axillary lymph node dissection (ALND) omission in SLN+ patients, despite critiques regarding non-uniformity of radiation fields. We conducted an observational study (LISEN) where whole breast radiotherapy (WBRT) was planned with tangential fields without nodal irradiation in patients eligible for the Z0011 trial. Methods Inclusion criteria were female patients with histologically proven BC, cT1-2cN0, planned conservative surgery, no neoadjuvant therapy. Patients were stratified into two groups: micrometastatic (pN1mic, group 1) and macrometastatic (pN1a, group 2) lymph nodes. Tangential field WBRT was mandatory. Clinical outcomes were analysed, measured from surgery until the first event. Results In all, 199 patients underwent conservative surgery and SLN biopsy; 133 patients meeting criteria were analysed: 41 patients (30.8%) pN1mic and 92 (69.2%) pN1a. The 5‑year disease-free survival (DFS) was 95.0% (85.9–100%) in group 1 and 93.0% (86.3–100.0%) in group 2 (p = 0.78). Overall survival (OS) was 100% (100–100%) in group 1 and 97.4% (92.4–100%) in group 2 (p = 0.74). For the whole cohort DFS and OS were 93.6% (88.2–99.4%) and 96.9% (91.5–100.0%), respectively. For groups 1 and 2, the 5‑year outcomes were 5.0% (0.0–14.4%) and 2.3% (0.0–6.1%) for local recurrence (p = 0.51), and 6.2% (0.0–17.4%) and 7.0% (0.0–13.7%) for distant metastasis (p = 0.61), respectively. In group 1, regional recurrence (RR) and local regional recurrence (LRR) were 5.0% (0.0–14.1%; p = 0.13). In group 2, RR and LRR were 0.0% (0.0–0.0%). Conclusion Our results showed good regional control in patients who met the Z0011 trial criteria. WBRT, without nodal surgery or RT, avoiding axillary morbidity, seems to be a good choice.

Radiation therapy of breast cancer in the Nahe Breast Center: first results of an analysis in the context of health services research

“…It also shows the high professional and technical quality of all employees in our practice. The results confirm that postoperative radiation is the most important and effective measure to reduce the risk of local recurrence [1][2][3][4][5][6][7][8][9][10][11][12]. If we follow the current literature, this finding applies to all breast cancer subgroups.…”

The role of radiotherapy in the updated German S2k guideline for management of Merkel cell carcinoma

“…In the case of a positive sentinel lymph node, lymphadenectomy does not necessarily have to be performed, but radiotherapy is alternatively recommended in the updated S2k guideline. According to new data from retrospective studies and prospective databases, the outcomes after radiotherapy are not inferior to those of lymphadenectomy, similar to the situation in other tumor entities [ 12 , 13 ]. For instance, in a dataset where completion lymph node dissection (CLND) was recommended in patients with acceptable perioperative risk and therapeutic radiotherapy, in those with high perioperative risk, the 3‑year nodal recurrence-free survival was 76% after CLND and 91% after radiotherapy ( p = 0.3) [ 14 ].…”

Impact of inter-observer variability on first axillary level dosimetry in breast cancer radiotherapy: An AIRO multi-institutional study

“…Although the quantification of incidental dose to the axilla is hindered by the paucity of RT technical parameters for dosimetric correlations, it has been investigated in small, dedicated reports or in studies reproducing the condition of treatment of the landmark BC trials. [5][6][7][8][9][10] The SENOMAC trial, which has recently closed the accrual, challenged the need to irradiate L1 for slight sentinel node involvement and recommended limiting the regional RT field to L2, L3 and L4, regardless of the arm of randomisation. 11 In the locoregional RT, L1 is expected to receive a certain amount of the dose from the contribution of the breast/chest wall and the infra/supraclavicular fields, especially when this latter includes the whole or part of the second axillary level (L2).…”