Breast Cancer Health Center

continued...

Adjuvant radiation therapy postmastectomy in axillary node-positive tumors:

• For one to three nodes: unclear role for regional radiation (infra/supraclavicular nodes, internal mammary nodes, axillary nodes, and chest wall).
• For more than four nodes or extranodal involvement: regional radiation is advised.

Adjuvant systemic therapy:

An International Consensus Panel proposed a three-tiered risk classification for patients with negative axillary lymph nodes.[54] This classification, with some modification, is described below:

Table 6. Risk Categories for Women With Node-Negative Breast Cancer

The original Consensus Panel classification also required that women be 35 years or older to be included in the low-risk group and included women 35 years and younger in the high-risk group, based admittedly on indirect evidence. Traditionally, certain uncommon histologies (e.g., tubular, medullary, and mucinous) have also been associated with favorable prognosis and may be considered as low-risk factors. Some additional tumor characteristics that may eventually prove helpful in the prognosis of node-negative disease include the tumor proliferative fraction (S-phase) and the level of HER2/neu expression.

Regardless of how one chooses to characterize node-negative tumors, evidence from clinical trials suggests that various types of adjuvant therapies benefit certain subgroups of patients with these kinds of tumors. The same is true for women with node-positive breast cancer. What has become clear after reviewing results from multiple breast cancer treatment trials is that hormone therapy and chemotherapy regimens generally offer the same proportional benefit to women irrespective of their axillary lymph node status. The selection of therapy is most appropriately based upon knowledge of an individual's risk of tumor recurrence balanced against the short-term and long-term risks of adjuvant treatment. This approach should allow clinicians to help individuals to determine if the gains anticipated from treatment are reasonable for their particular situation. The treatment options presented below should be modified based upon both patient and tumor characteristics.

Table 7. Adjuvant Systemic Treatment Options for Women With Axillary Node-Negative Breast Cancer