Abstract P4-09-05: Long Term Follow-Up of Breast Cancer Patients of the Swedish Cancer Institute Breast Cancer Research Registry

Abstract

Abstract Background: Since 1990 the Swedish Cancer Institute Breast Cancer Research Registry has accrued over 10,900 cases with a 92% follow-up rate. We analyzed the incidence of recurrence over time to evaluate the appropriate duration of our long term follow-up. Methods: Patients with stages 1-3 disease were selected for study. Stages 0 and 4 disease, and neo-adjuvant treatment patients were excluded. The incidence and time to recurrence was compared with tumor grade [Bloom Richardson (BR) score], hormone receptor, HER2 status, stage, number of positive lymph nodes, surgery, radiation therapy, chemotherapy, hormone therapy and menopausal status. Results: The recurrence rate was 7.8% (740/9455) of which 68% (500) occurred in the first 5 years, 24% (179) occurred between 5 and 10 years, and 8% (61) occurred after 10 years. Factors that had a significant (P<0.05) relationship with the incidence of and time to recurrence were: stage, grade, hormone receptor status, number of positive lymph nodes, hormone therapy and radiation therapy. In the hormone receptor negative group, 15% (181/1205) recurred - 86% within 5 years, 12% between 5 and 10 years and 1.7% over 10 years. In the hormone receptor positive group, 7.3% (522/7201) recurred - 62% within 5 years, 28% between 5 and 10 years and 10% over 10 years. Of the patients with negative nodes, 4.7% (255/5405) recurred - 65% within 5 years, 27% within 5 to 10 years and 7.5% over 10 years. For the patients with 1 - 3 nodes positive, 12.6% (222/1769) recurred - 67% within 5 years, 24% between 5 and 10 years and 10% over 10 years. For 4-9 nodes positive, 25.3% (121/478) recurred - 79% within 5 years, 20% between 5 and 10 years and 6.6% over10 years. For greater than 10 nodes positive, 40.9% (92/225) recurred - 75% within the first 5 years, 20% between 5 and 10 years and 5.4% over 10 years. A BR score of 3-5 resulted in 2.0% (32/1574) recurrences - 63% within 5 years, 25% between 5 and 10 years and 13% over 10 years. A BR score of 6-7 resulted in 5.1% (131/2559) recurrences - 73% within 5 years, 26% between 5 and 10 years and 1.5% over 10 years. A BR score of 8-9 resulted in 11.3% (179/1581) recurrences - 89% within 5 years, 10% between 5 and 10 years and 0.6% over 10 years. Conclusion: The incidence of recurrence and the rate of recurrence of breast cancer was greatest for tumors that were hormone receptor negative, had a high number of positive lymph nodes and were high grade (BR 8-9). The incidence of recurrence after 10 years was under 0.5% overall and under 1.0% for most groups. The exception was patients with over 10 nodes positive (2.2%). However, patients with low grade (BR 3-5), hormone receptor positive or 1-3 positive lymph nodes, or patients treated with total mastectomy without irradiation or hormone therapy had over 10% of their recurrences occur after 10 years. The old adage that after ten years one is cured does not apply to these low risk patients. Nor does it apply to the high risk patients although their outlook is markedly improved by 10 years. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-09-05.