Background: Recent studies have shown that breast cancer detected by screening has a more favorable prognosis than interval breast cancer. To further understand the biologic significance of this finding, we investigated the association of disease recurrence, local and distant, with the method of detection of the primary breast cancer in a cohort of 1686 women treated with breast conservation.
Patients and methods: The charts of 1686 women with primarily stage I or II invasive breast cancer treated by breast conservation between 1977 and 2002 were reviewed. The median length of follow-up was 6 years. Univariate and multivariate analyses using binary logistic regression were performed for 2 subgroups: (1) those with local recurrence versus those without; and (2) those with distant metastasis versus those without distant metastasis.
Results: Our data confirmed several of the well-known risk factors for local and distant recurrence. In addition, we found that individuals with breast cancer detected on physical examination alone have a significantly higher risk for local recurrence compared with patients with cancer detected on mammogram alone, independent of tumor size (odds ratio [OR], 2.369; 95% CI, 1.235-4.547; P = .01). We also found a similar correlation for risk of distant metastasis in these 2 groups of women (OR, 2.201; 95% CI, 1.211-3.998; P = .01).
Conclusion: Breast cancers that are palpable might represent an aggressive biologic subtype with an increased risk of local and distant recurrence. Risk stratification might need to include this clinical feature in addition to conventional prognostic factors.