According to a study published in the European Journal of Cancer, predictors of local or regional breast cancer recurrence in women treated for stage I or stage II breast cancer include young age and breast conserving therapy.
Early breast cancer (cancer that has not spread from the breast and some underarm lymph nodes) is often treated with breast-conserving therapy. Breast-conserving therapy includes the surgical removal of the cancer along with a margin of healthy tissue; axillary lymph nodes are also tested or removed. Following surgery, women undergo radiation therapy, chemotherapy, and/or hormone therapy to reduce the risk of recurrences over surgery alone. A mastectomy, on the other hand, is the removal of the entire breast.
To identify factors-including type of surgery-that may influence the probability of recurrence after breast cancer treatment, researchers in the Netherlands analyzed data from three breast cancer clinical trials. A total of 3602 women with stage I or stage II breast cancer were included in the analysis. Fifty-five percent of the women were treated with breast-conserving therapy and 45% were treated with mastectomy.
The primary study outcome was isolated local or regional recurrence. This referred to a recurrence involving the breast, armpit, or chest wall on the same side as the initial breast cancer. In order to be classified as “isolated”, there could be no distant metastases or death during the two years following the recurrence.
The other outcome included distant metastases, death, and non-isolated local or regional recurrence. Non-isolated local or regional recurrence referred a local recurrence or recurrence that was accompanied or followed (within two years) by distant metastases or death.
- 172 (5%) of the women developed an isolated local or regional recurrence.
- 1182 (33%) of the women experienced another event (distant metastasis, death, or non-isolated local or regional recurrence).
- After accounting for several other factors, breast conserving surgery was linked with an 82% increase in risk of isolated local or regional recurrence.
- Compared to women who were over the age of 50 at the time of diagnosis, women age 35 or younger had a more than two-fold increase in risk of isolated local or regional recurrence.
- Young age was also linked with an increased risk of distant metastases, death, or non-isolated local or regional recurrence. Type of surgery, however, was not linked with these outcomes.
The researchers conclude that both young age and breast-conserving therapy are linked with an increased risk of isolated local or regional cancer recurrence. They note, however, that the link seen with breast-conserving therapy will likely decrease as a result of better patient selection and treatment techniques.
Because isolated local or regional recurrences are potentially curable, the researchers recommend that women who are diagnosed with breast cancer at a young age or who undergo breast-conserving therapy should be closely monitored to detect recurrences at an early stage.
Reference: de Bock GHF, van der Hage JA, Putter H et al. Isolated Loco-Regional Recurrence of Breast Cancer is More Common in Young Patients and Following Breast Conserving Therapy: Long-Term Results of European Organisation for Research and Treatment of Cancer Studies. European Journal of Cancer. 2006:42:351-356.