Impact of axillary staging after neoadjuvant chemotherapy for breast cancer on arm morbidity: one-year results from the AXSANA cohort study

Abstract Introduction Individuals with breast cancer who convert from node positivity to node negativity through neoadjuvant chemotherapy (NACT) may undergo sentinel lymph node biopsy (SLNB), targeted axillary dissection (TAD), or axillary lymph node dissection (ALND) depending on relevant guidelines. These methods’ significance for arm morbidity is insufficiently explored. The international prospective AXSANA cohort study (NCT04373655) aims to assess patient-reported arm morbidity after SLNB, TAD, or ALND following NACT. Method The AXSANA study includes patients with node-positive T1 to T4c breast cancer scheduled for NACT. Patients were grouped according to their surgical staging method, i.e., SLNB, TAD, and ALND. Arm morbidity was assessed using the Lymph-ICF-UL questionnaire. Score differences between baseline and one year after surgery and categorized scores one year after surgery were evaluated using linear/logistic regression with confounder adjustment. Result Out of 1,588 included patients, 1,293 (81.4%) had completed the one-year questionnaire until January 2025. Arm function (e.g., stiffness, swelling, paraesthesia, pain, or loss of strength) deteriorated significantly more after ALND (mean score change 12.3, SD 26.8), than after SLNB (2.8, SD 29.1) or TAD (6.6, SD 23.0) (both P < 0.001). Severe arm function problems one year after surgery were reported by 24,4% of ALND patients, compared to approximately 14% in the SLNB and TAD groups, (OR 0.51, 95% CI 0.33 – 0.79; P = 0.002, and OR 0.58, 95% CI 0.45 – 0.76; P < 0.001, respectively). No significant differences between SLNB and TAD groups were observed. Discussion This study demonstrates that SLNB or TAD following NACT preserves arm physical function better than ALND.