Neoadjuvant and adjuvant therapy breast cancer

 

References:

1. ASCO 2021 guideline: https://pubmed.ncbi.nlm.nih.gov/33507815/

Counseling patients with residual disease after neoadjuvant chemo about adjuvant therapy

Adjuvant ChT reduces the relative recurrence risk and improves survival in women by 25%-30% irrespective of the subtype.

1. HER 2+: TCHP if node+ or 2 cm ( can use if 1.5 cm or higher). APT regimen if tumor < 3 cm, node neg.

2. Triple negative : patients with clinically node-positive and/or at least T1c TNBC be offered an anthracycline- and taxane-based neoadjuvant regimen.

3. ER positive: CREATE X trial did not show an OS or DFS benefit in ER+ pt rx with capecitabine. So SOC remains endocrine manipulation with 3 yr ribociclib or 2 yr abemaciclib.

NATALEE trial:  At 3 years, invasive disease–free survival was 90.4% with ribociclib plus an NSAI and 87.1% with an NSAI alone (hazard ratio for invasive disease, recurrence, or death, 0.75; 95% confidence interval, 0.62 to 0.91; P=0.003). Secondary end points — distant disease–free survival and recurrence-free survival. Dose of ribo--> 400 mg per day  3 weeks on, 1 week off. 5000+ patients enrolled of which 2000 were stage II.

-MONARCH E trial: over 5000 patients with high risk ER+ breast cancer with one of the following:

• 4 LN or more positive
• 1-3 LN+ but with 2 out of the following 3: Ki 67 over 20 %, tumor 5 cm or more, or grade 3

150 mg BID abema daily for 2 yr--> 3.5% absolute improvement in 2-year IDFS rates (92.2% v 88.7%) and 25% risk reduction of developing invasive disease

Deciding neoadjuvant hormonal therapy versus chemo in post menopausal women with T2 or node positive tumors

The combination of low grade and/or low Ki-67 level with strong ER/PgR expression and endocrine response to a short course of preoperative ET may serve as surrogates for a sufficiently favourable biology. 

Impact of neoadjuvant therapy on local therapy:

Limited data indicate that in patients with nodal metastases, downstaging because of neoadjuvant chemotherapy may allow for less extensive surgery for the axilla and thereby reduce surgical complications such as lymphedema and dysesthesias. the conversion rate from BCS-ineligible to BCS-eligible ranged from 43% to 53%.( CALGB and BRIGHTNess trials)