Patterns of breast cancer relapse

Although breast cancer is the major cause of cancer-related death in women, there is little comprehensive information on long-term outcomes, particularly pertaining to site of relapse. The Strathfield Breast Centre (TSBC) is a multidisciplinary breast clinic that has collected patient data prospectively over 14 years.

All women with invasive, non-metastatic breast cancer, referred to TSBC from 1989 until 2002, were studied (n=2509). After initial treatment, patients were reviewed at 3-12-month intervals, including annual mammography and/or breast ultrasound. Information was collected on demographics, pre- and post-operative management and patient outcomes. Survival was analysed by the method of Kaplan and Meier.

The mean age was 58 years and median follow-up 4 years (range <1-14) with complete data for 81%. In total, 456 patients (18%) had a local, nodal or distant relapse. The most common site of first relapse was to bone (in 125 patients), followed by local recurrence (124), lung (73) and liver (57). The median interval from primary breast surgery until recurrence was 2.3 years and disease-free intervals correlated to survival (p<0.0001). After local recurrence the 5-year survival was 41%, vs. 20% for nodal and 13% for distant recurrence (p<0.0001). Following breast-conserving surgery, the 5-year disease-free survival after local recurrence was 49.4%, vs. 33.1% after chest wall recurrence (p=0.0361). Of distant relapses, bone metastases had the best prognosis, with median survival 2.4 years.

These data provide information on treatment outcomes in a multidisciplinary setting and statistical information that will be useful when discussing the fears and expectations of patients after the diagnosis of breast cancer.