About 20% of breast cancer patients have tumors that over-express the human epidermal growth factor receptor 2 (HER2), a characteristic that has been associated with lower breast cancer survival rates. For these breast cancer patients, treatment with the drug Herceptin has provided substantial improvements in breast cancer recovery. However, most of the breast cancer research in this area appears to have focused on tumors greater than 1 cm in size. Two studies (summaries can be read HERE and HERE) and one editorial (available for free HERE) recently published online in the Journal of Clinical Oncology, examined the risk of breast cancer recurrence in patients with small (< 1 cm) HER2-positive tumors.
Both studies reported an increased risk of breast cancer recurrence of about 2-5 fold in patients with small, HER2-positive tumors. Additional results included:
5-year recurrence-free survival was only 77% in patients with HER2-positive tumors compared to 94% in patients with HER2-negative tumors.
Patients with HER2-positive tumors had about 5 times the rate of breast cancer recurrence compared to patients with hormone receptor-positive tumors.
Breast cancer patients who were both hormone receptor-positive and HER2-positive had a worse prognosis (by about 5-fold).
These studies suggest that breast cancer patients with HER2-positive tumors, even small ones, are at a substantially increased risk of breast cancer recurrence. The accompanying editorial discusses the pros and cons of Herceptin treatment in this group of breast cancer patients. In general, the editorial suggests that risks of adjuvant therapy and Herceptin side effects might make it hard to justify their use for tumors smaller than 5 mm. However, for larger (6 mm or greater) HER2-positive tumors, this type of treatment might warrant consideration.
This new breast cancer research highlights the importance of personalized breast cancer treatment. It is clear that there are several specific types of breast cancer and that each of these types of breast cancer need to be treated in a specific manner whenever possible. By tailoring breast cancer treatment, the medical profession hopes to decrease recurrence and improve survival while minimizing serious side effects.
While the medical and scientific communities continue to make amazing discoveries in breast cancer prevention and treatment, you can help reduce your own breast cancer risk by making important lifestyle changes. Read my book Fight Now: Eat & Live Proactively Against Breast Cancer (www.fightBCnow.com) to learn more.