With a median follow-up of 18 years among 1,616 patients, Conny Vrieling, M.D., Ph.D., of the Clinique des Grangettes, Geneva, Switzerland, and coauthors report that young age and the presence of ductal carcinoma in situ (DCIS) adjacent to the invasive tumor were associated with increased risk of ipsilateral (on the same side of the body) breast tumor recurrence (IBTR) at long-term follow-up. Also, high-grade invasive tumors relapsed more frequently only during the first five years, according to the findings.
The 20-year cumulative incidence of IBTR was 15 percent with 160 cases found, the results indicate.
“Patients with high-grade invasive tumors should be monitored closely, especially in the first five years. The impact of DCIS remained constant over time, indicating that long-term follow-up is necessary. The boost significantly reduced IBTR in these patients,” the study concludes.