Current guidelines recommend asymptomatic surveillance of breast cancer only for the detection of locoregional recurrences. Researchers from the Asan Medical Center in Seoul, Republic of Korea, conducted a retrospective 10-year survival analysis of a large cohort of patients with recurrent breast cancer to identify the impact of early detection on survival outcomes and presented the findings at the .
The investigators assessed 4,188 operable patients with breast cancer who completed standard treatment at Asan Medical Center between 2006 and 2008. Of that cohort, 469 had recurrent breast cancer with a median disease-free interval of 35.3 months (range = 2.8–97.6 months). Among those with recurrent disease‚ 23.7% had local metastases (e.g., ipsilateral breast‚ skin‚ chest wall)‚ 22.6% had regional metastases (e.g., ipsilateral axillary‚ internal mammary lymph nodes), and 53.7% had distant metastasis.
Researchers classified patients based on recurrence detection via asymptomatic surveillance (n = 162; 34.5%) or symptom-guided management (n = 307; 65.5%). Asymptomatic screening included mammography‚ breast ultrasound‚ serum tumor marker, and systemic images (e.g., chest X-ray‚ bone scan‚ positron emission tomography). Among the local‚ regional, and distant metastases, symptom-guided management led to detection in 14.9%, 5.5%, and 15.1%, respectively.
The 10-year overall survival (OS) did not differ between the asymptomatic surveillance and symptom-guided management groups (81.3 versus 78.8 months; p = 0.778). Among patients with distant metastasis‚ 10-year OS was not significantly different between the detection cohorts (70.3 versus 66.7 months; p = 0.846) and was similar according to stage or subtype. Among patients with local recurrence‚ 10-year OS was 95.1 months (p = 0.809)‚ although the researchers said that the number of events may have been insufficient to show significant difference. Among patients with regional recurrence, the asymptomatic cohort appeared to have longer OS compared to the symptom-guided group (86.1 versus 63.4; p = 0.004).
Cox regression analyses showed that asymptomatic detection led to significantly better survival rates (hazard ratio = 3.9; 95% confidence interval = 1.6–9.5). The finding was more evident in patients with hormone receptor-negative primary breast cancer (69.9 versus 47.9; p = 0.029). Mammography detected just 8.6% (n = 7 out of 80) of regional recurrences.
“Although with limitation that surveillance method varied widely‚ we emphasize the role of asymptomatic surveillance of regional nodal evaluation including breast ultrasound,” the researchers concluded. The findings should be validated in a prospective clinical trial.