Abstract 254P
Background
Patients with breast cancer achieving a pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) have a favourable outcome. However some patients may relapse. This study aimed to identify patterns of relapse after pCR in breast cancer treated with NACT to refine initial workup stage and follow-up recommendations.
Methods
Breast cancers patients treated with NACT in a single institution. pCR was defined as absence of residual invasive cancer in the primary tumour and axillary lymph nodes. We assessed correlation between presence of hormone receptor and distant site of relapse. We applied Pearson's chi-squared test. P<0.05 was considered statistically significant.
Results
537 patients with breast cancer received NACT from 1998 to 2018. Median follow-up was 64,5 months. 119 achieved a pCR (22,2%). Of them, 11 (9,2%) presented a distant recurrence as first place of relapse. Five-year DDFS was 91,6%. All the patients were stage III and grade III at diagnosis. Among patients with hormone receptor-negative (RH-) (n=6), 5 had central nervous system (CNS) mono-metastatic site relapse in the 2 years following breast surgery. In contrast, all patients with hormone receptor-positive (RH+) (n=5) had multiple liver metastases (also one with synchronous lung metastases and other one with bone metastases) in the 3 years following breast surgery. The differences between RH and distant site of relapse were statistically significant (χ2=11, p=0,004). Strong Association between RH- and progression at CNS was observed (OR: 6, confidence interval 95%, [CI] 1.003-35.908).
Conclusions
Among breast cancer patients achieving pCR those with RH- tumors tend to recur in the CNS in a unique site. This is of special relevance because guidelines do not recommend brain staging at the initial diagnosis if the patient has no symptoms. In accordance with our results, we would suggest a brain imaging test at diagnosis in stage 3, grade 3, and RH-, since this is a potentially curable situation in case of single metastasis. In addition, we must be alert to any symptoms that may suggest brain progression during the first years of follow-up.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.