Recurrence risk in breast cancer varies throughout the follow-up time. We examined if these changes
are related to the level of expression of the proliferation pathway and intrinsic subtypes.
Results: Luminal A displayed a slow risk increase, reaching its maximum after three years and then remained steady.
Luminal B presented most of its relapses during the first five years. HER2-enriched tumors show a peak of recurrence
nearly twenty months post-surgery, with a greater risk in Ki-67 ≥14%. However a second peak occurred at 72 months
but the risk magnitude was greater in Ki-67 <14%. Triple negative tumors with low proliferation rate display a smooth
risk curve, but with Ki-67 ≥14% show sharp peak at nearly 18 months.
Conclusions: Each intrinsic subtype has a particular pattern of relapses over time which change depending on the
level of activation of the proliferation pathway assessed by Ki-67. These findings could have clinical implications both
on adjuvant treatment trial design and on the recommendations concerning the surveillance of patients.
; Pajares, Bella; Vicioso-Recio, Luis Prudencio
