Recurrence pattern in breast cancer. A comparison between hormone-dependent and non-hormone-dependent carcinomas

Introduction and aims: Breast cancer is a heterogeneous group of tumours. The oestrogen receptor positivity was seen as a good prognostic factor for recurrence and survival. This concept has changed with studies with longer follow-up and larger series. It is believed that this effect of better prognosis in hormone-dependent tumours is lost after the first five years of monitoring. Materials and methods: A case review study comparing recurrence between hormonedependent tumours and tumours with negative oestrogen receptors was undertaken. We evaluated the cases of recurrence, local and systemic, diagnosed between 1996 and 2010, totalling 88 cases. Sixty-five cases were oestrogen receptor positive, 20 cases oestrogen receptor negative, and 3 cases unknown. Almost all (99%) patients with oestrogen receptor positive tumours received adjuvant hormone therapy. Results: The pattern of recurrence in negative estrogen receptors tumors began with an initial peak at 2 years, then steadily decreasing. This pattern differed from the hormonedependent tumours, with a peak incidence of recurrence between the third and sixth years, and then gradually decreasing over longer follow-ups (15 to 20 years). Logistic regression with the dependent variable “without recurrence at 5 years follow-up” showed an association between tumour size (p=.029) and hormone-dependency (p=.05). No relationship was found in the remaining variables of the model (age, menopausal status, lymph node involvement, TNM classification). Conclusion: These data confirm a different pattern of recurrence in both groups. Hormone-dependent carcinomas had a higher risk of recurrence at about 4 to 6 years and then gradually decreased. By contrast, only 16.8% of negative oestrogen receptors tumours had a recurrence after the first 5 years of follow-up.