Abstract 2698
Background
Triple negative breast cancers are a heterogeneous group of breast cancer candidate to adjuvant chemotherapy in a large majority of cases. However, literature data indicate that the diagnosis of special types of breast cancer might be associated with a different outcome if compared with invasive ductal carcinoma with similar biological features and stages. Selected triple negative apocrine breast cancer can have an extremely good prognosis.
Methods
Among the 210 women with first primary invasive apocrine non metastatic breast cancer operated between January 1998 and December 2016 at European Institute Oncology, Milan, we identified 24 patients with pT1-pT2, node-negative, triple negative subtype and Ki-67 ≤20% who did not receive adjuvant chemotherapy. We compared the outcome of this cohort with a similar group of 48 patients with ductal tumors who received adjuvant chemotherapy, matched by pathological stage and biological features (matching ratio 1:2).
Results
The median age was 63 and 50 years in the apocrine and ductal group, respectively. The mean value of Ki-67 expression was 12% in the apocrine group and 14% in the ductal group. 83% of apocrine tumors had size less than 2 cm, compared with 71% of ductal tumors. After a median follow-up of 6.6 years no patients in the apocrine group experienced a breast cancer related event compared with 12 events (including 5 loco-regional recurrences, 3 distant recurrences e 4 contralateral tumors) in the ductal carcinoma group (Gray test p-value=0.015).
Conclusions
The outcome of selected apocrine triple negative breast cancer patients is excellent and possibly deserves a treatment de-escalation. Multicenter projects focusing on the possibility to avoid adjuvant chemotherapy in selected subtypes of triple negative breast cancers with favorable outcome are warranted.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
G. Cancello: Honoraria (self): Pierre Fabre. E. Montagna: Honoraria (self): Pierre fabre; Honoraria (self): gentili. E. Munzone: Honoraria (institution), Advisory / Consultancy: Pierre Fabre; Honoraria (institution), Advisory / Consultancy: Genomic Health. S. Dellapasqua: Travel / Accommodation / Expenses: Roche. M.A. Colleoni: Advisory / Consultancy: Pierre Fabre; Advisory / Consultancy: Pfizer; Advisory / Consultancy: OBI Pharma; Advisory / Consultancy: Puma Biotechnology; Advisory / Consultancy: Celldex; Advisory / Consultancy: AstraZeneca. All other authors have declared no conflicts of interest.
Resources from the same session
3330 - Tumour-infiltrating lymphocytes and BRCA-like status in stage III breast cancer patients treated with intensified carboplatin-based chemotherapy
Presenter: Leonora De Boo
Session: Poster Display session 2
Resources:
Abstract
3971 - Unravelling the biological characteristics of MammaPrint extreme risk subgroups
Presenter: Rajith Bhaskaran
Session: Poster Display session 2
Resources:
Abstract
5871 - Residual Cancer burden as a prognostic factor in a large series of Neoadjuvant chemotherapy. Subgroup analysis per molecular surrogated subtypes
Presenter: Catalina Falo
Session: Poster Display session 2
Resources:
Abstract
5014 - Clinical validation of CanAssist Breast in a Spanish cohort
Presenter: Manjiri Bakre
Session: Poster Display session 2
Resources:
Abstract
2787 - Meta-analysis on association of pathological complete response with long-term survival outcomes in triple-negative breast cancer
Presenter: Peter A. Fasching
Session: Poster Display session 2
Resources:
Abstract
4301 - Immune infiltrate composition across intrinsic subtypes in hormone receptor (HR)+/HER2- early breast cancer (BC) enrolled in the prospective LETLOB trial
Presenter: Gaia Griguolo
Session: Poster Display session 2
Resources:
Abstract
3205 - Frequency of germline mutations in women's cancer susceptibility genes in a large cohort of Chinese breast cancer patients
Presenter: Ning Liao
Session: Poster Display session 2
Resources:
Abstract
4091 - Triple blinded Prospective Study assessing the Impact of Genomics & Artificial Intelligence Watson For Oncology (WFO) on MDT’s Decision of Adjuvant Systemic Therapy for Hormone Receptor Positive Early Breast Carcinoma-
Presenter: Somashekhar Sampige Prasannakumar
Session: Poster Display session 2
Resources:
Abstract
4359 - Prognostic significance of Progesterone Receptor levels in luminal-like Her2- early Breast Cancer patients. A retrospective single Cancer Center analysis.
Presenter: Anna Diana
Session: Poster Display session 2
Resources:
Abstract
1369 - PAM50 HER2-enriched subtype and pathological complete response in HER2-positive early breast cancer: a meta-analysis
Presenter: Francesco Schettini
Session: Poster Display session 2
Resources:
Abstract