Triple-negative breast cancers are a heterogeneous group and may not always be associated with lymph node spread, a new study shows.

The study of 145 triple negative breast cancers (i.e, cancer which is estrogen receptor-negative, progesterone receptor-negative and HER2-negative) in 128 women found that about 23% were moderate or low-grade lesions, said Cecilia Mercado, MD, of New York University School of Medicine, and an author of the study.

Triple negative breast cancer is found in about 15% of breast cancer patients and the patients are usually younger.

The study found that 11 of the 145 cancers had a low histologic grade. Only one of these patients had evidence that their cancer had spread into their lymph nodes. Twenty-three cancers were moderate grade lesions; only five of these 23 had spread into the lymph nodes. That compares to 37 of 111 cancers with a high histologic grade which had lymph node metastases, Dr. Mercado said.

“Our preliminary results show that triple negative breast cancers are a heterogeneous group. Although many are high grade lesions, some are moderate or low grade demonstrating a lower rate of lymph node metastasis,” Dr. Mercado said.

Source: American Roentgen Ray Society