Study clarifies risk of recurrence for high-risk breast cancer patients

High-risk breast cancer patients do not appear to have a higher risk of relapse than the general breast cancer population during the first two years after diagnosis, unless their cancer has spread to more than 10 axillary lymph nodes, Italian researchers reported at the 2nd ESMO Scientific & Educational Conference (ESEC) in Budapest, Hungary.

Dr. Marina Cazzaniga from Treviglio Hospital, Italy, and colleagues in the NORA study, have been studying 3,500 patients being treated for breast cancer. They identified five groups of patients considered at high risk and analyzed their rate of relapse.

The five groups were:

• patients whose tumors were estrogen receptor positive/progesterone receptor negative (ER+/PgR-)
• those who had tumors with a 3+ score for HER2 protein overexpression
• those with 1 to 3 positive axillary nodes
• those with 4 to 10 positive nodes
• patients with more than 10 positive nodes

"We found that patients with ER+/PgR- status, or high expression of HER2 or fewer than 10 positive axillary nodes do not seem to have an increased risk of relapse in comparison to the whole population," Dr. Cazzaniga said. "Massive involvement of axillary nodes seems to be the only factor associated with a higher risk of developing distant or local relapse."

"Our results reflect what happens in an unselected population of breast cancer patients, so they are very close to the clinical reality," Dr. Cazzaniga added. "In clinical practice, benefits do not derive only from one study, but from an accurate use of different strategies resulting from different trials and tailored to individual patients. Our study probably reflects the magnitude of benefits of the application of various studies on the whole population."

The finding could be very important for patients, she said. "The identification of peculiar characteristics allows clinicians to design specific therapies for specific patients. That's why results must fit clinical practice."

Median follow-up in the study so far is 21.7 months. The risk of recurrence in breast cancer patients presents 2 peaks: the first approximately within 2 years, the second 5 years after surgery.

"We believe our results well describe the natural history of breast cancer in the first 2 years. Longer follow-up will demonstrate if also the second peak changes or not," Dr. Cazzaniga said.

Commenting on the report, Dr. Ahmad Awada from Jules Bordet Institute, Brussels, Belgium, said, "At this time we do not know which patients would benefit most from upfront therapy with aromatase inhibitors compared to the sequential approach of Tamoxifen followed by aromatase inhibitors. This paper showed that patients with N+>10 had an increased risk of relapse during the first 2 years. Consequently, these data called for an upfront use of adjuvant AI in this group of patients at high risk of relapse in the first 2 years."