3447 - Influence of first treatment delay on survival among breast cancer subtypes

Background

Conflicting results on the the impact of cancer first treatment delay (FTD) on survival have been reported between several studies, and its importance has yet to be determined. We currently do not have any study in breast cancer (BC) analyzing how FTD influences the prognosis of the patients according to different inmunophenotypes. We conducted a study where we examined the relationship between survival and three periods of diagnostic-therapeutic delay, 30, 60 and 90 days.

Methods

This multicentre cohort study included BC patients from screening CAMISS PROJECT, during 2000-2006 with follow-up until 2014. Cox regression analysis, crude and multivariate, was applied to estimate risk of death. The Hazard Ratio (HR) was adjusted by FTD, stage, immunophenotypes of BC and comorbidity

Results

The study included 738 women aged 45-69 years. Median time of FTD was 58 days. First treatment aplied was surgery for all populations. 42% of BC presented as stage I and 34% stage II. 24% of patients had comorbidities. 21% expressed HER2, 80% estrogen receptors and 61% progresterone. There were 53% of Luminal A tumors, followed by 27% Luminal B, of which 10% also expressed HER2, 9% were HER2 overexpressing tumors, and 11% triple negative. In the crude analysis none of the three FDT cut-off points had a significant relationship with overall survival. Multivariate analysis adjusted for phenotypes, comorbidity and stage, showed worse prognosis tendency in DT30 and DT90, with a statistically significant level in DT60, hazard ratio [HR] 1,57; 95% IC (1,04-2,38). When we analyzed survival according to DT60 and BC subtypes there was more significant risk of death among HER2 subtype HR 2,91; 95% IC (1,63-5,21) and triple negative HR 1,90; 95% IC(1,01-3,60) comparing to Luminal A. No relationship was seen in Luminal B; Table.Table:

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Conclusions

Waiting 60 days to initiate treatment was associated with a significantly worse overall survivall among triple negative and HER2 BC. We consider it of importance to offer early treatment to aggressive BC subtypes.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

REDISSEC-CAMISS Group-(Research Network in Health Services in Chronic Diseases).

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.