Study Urges Against Lymph Node Dissection for Abemaciclib in ER-Positive Breast Cancer

The research published in the journal The Lancet Oncology has revealed that complete axillary lymph node
dissection (cALND) to determine the indication for abemaciclib (to avoid cancer
recurrence over a five-year period) is linked with severe arm morbidity and
should not be recommended for this purpose.

Abemaciclib is an adjuvant
CDK4/6 inhibitor to prevent cancer recurrence after initial treatment. cALND
is the only prognostic tool available that can detect four or more nodal
metastases (pN2–3), which is the only situation where adjuvant abemaciclib is
recommended in this case. Alternatively, this procedure could pose significant
arm problems for patients.

Against the above background, Prof Jana de Boniface,
breast Center, Capio St Goran’s Hospital, Stockholm, Sweden, and colleagues aimed
to practically assess the possible benefits and risks of this approach for
individual patients participating in the ongoing SENOMAC trial.

For this purpose, 2766
patients were enrolled between Jan 31, 2015, and Dec 31, 2021,
for a randomised, phase 3, SENOMAC trial. Patients
aged 18 years or older, regardless of performance status, who had clinically
node-negative T1–T3 breast cancer with one or two sentinel node
macrometastases, were recruited from 67 sites across five European countries. These
patients were randomly assigned in a 1:1 ratio using permuted block
randomization.

The study reveals that:

• 1705 (67%) is found eligible for this post-hoc
  study, in which 802 (47%) had a cALND and 903 (53%) had a sentinel lymph
  node biopsy only.
• Median age was 62 years (IQR 52–71), 1699
  (>99%) of 1705 patients were female, and six (<1%) were male.
• 1342 patients responded to questionnaires,
  after a follow-up of 45·2 months, reported severe or very severe impairment of
  physical arm function was reported in 84 (13%) of 634 patients who had cALND
  versus 30 (4%) of 708 who had sentinel lymph node biopsy only.

“cALND poses a
significant risk of severe arm complications, and therefore, its use should not
be recommended,” researchers concluded.

Reference: de Boniface,
J., Appelgren, M., Szulkin, R., Alkner, S., Andersson, Y., Bergkvist, L.,
Frisell, J., Gentilini, O. D., Kontos, M., Kühn, T., Lundstedt, D., Offersen,
B. V., Olofsson Bagge, R., Reimer, T., Sund, M., Christiansen, P., Rydén, L.,
& Tvedskov, T. F. (2024). Completion axillary lymph node dissection for the
identification of pN2–3 status as an indication for adjuvant CDK4/6 inhibitor
treatment: A post-hoc analysis of the randomised, phase 3 SENOMAC trial. The
Lancet Oncology. Advance online publication. https://doi.org/10.1016/S1470-2045(24)00350-4