Background:In human epidermal growth factor receptor 2 positive (HER2+) early breast cancer (EBC), lack of pathological complete response (pCR) to neoadjuvant therapy is associated with inferior prognosis.Despite pCR, some patients suffer distant relapse and predictive biomarkers are needed to identify them, as they may benefit from treatment escalation.We assessed clinical factors associated with distant recurrence (DR) following pCR in patients treated with neoadjuvant docetaxel, carboplatin, pertuzumab and trastuzumab (TCPH).Methods: Patients diagnosed with HER2+ EBC between 01/12/16-01/12/21 treated with neoadjuvant TCPH at The Christie Hospital were included.Data were collected from electronic case records.Association between age, body mass index, tumour/ nodal/overall clinical stage, tumour grade, dose intensity (85%), oestrogen receptor status, nodal fibrosis and distant recurrence free survival (DRFS) in those who achieved a pCR was analysed using Kaplan-Meier method and log rank test.Univariate cox regression was used to estimate hazard ratios (HR) and Bonferroni correction applied such that p < 0.006 was significant.Fisher's exact test was used to assess association between pCR and presence of brain metastases (BM) at time of DR.Results: 267 patients were included (median age 54, range 25-74) with a median follow up of 73 months.159 (60%) achieved pCR.There were 22 DR events, 8/159 (5%) in those with pCR and 14/108 (13%) in those without.Clinical stage was the only factor significantly associated with DR following pCR.6/32 (19%) with stage 3 disease experienced DR versus 2/127 (2%) with stage 1-2 EBC (HR 3.56, 95% CI 1.60-7.91,p = 0.002).Median DRFS was not reached in either group.BM were present at the point of DR in 5/8 (63%) of those with pCR and 6/14 (43%) of those with residual disease (p = 0.659).Conclusions: Patients with stage 3 HER2+ EBC at presentation have a high risk of relapse, even after neoadjuvant therapy and pCR.More than half relapse with BM and such patients may benefit from intensified neoadjuvant or adjuvant therapy with modern CNS penetrant regimens.Clinical trials should be considered to answer this question.
Brown et al. (Fri,) studied this question.