Additional prognostic value of the 70-gene signature (MammaPrint(®)) among breast cancer patients with 4-9 positive lymph nodes.

BACKGROUND

The 70 gene-signature (MammaPrint(®)) is a prognostic profile of distant recurrence and survival of primary breast cancer (BC). BC patients with 4-9 positive nodes (LN 4-9) are considered clinically at high-risk. Herein we examined MammaPrint(®) added prognostic value in this group.

PATIENTS AND METHODS

MammaPrint(®) profiles were generated from frozen tumours of patients operated from primary BC. Samples were classified as genomic Low Risk (GLR) or genomic High Risk (GHR).

RESULTS

Among the 173 samples, 70 (40%) were classified as GLR and 103 (60%) as GHR. Tumours in the GHR group were significantly more often ductal carcinomas (93%), grade 3 (60%), oestrogen and progesterone-negative, Her2 positive (25%). In the GLR category, the 5-year overall survival was 97% vs. 76% for in the GHR group (p < 0.01); Distant Metastasis Free Survival (DMFS) at 5 years was 87% for GLR patients and 63% for GHR patients (p < 0.01). In the Luminal A subgroup, the genomic profile was the only independent risk factor for DM and BC specific death.

CONCLUSION

In the Luminal A subgroup, MammaPrint(®) is an independent prognostic marker in BC patients with LN 4-9 and may be integrated in a selection strategy of patients candidate for more aggressive therapeutic approaches.