The nurse should know that according to current thinking, the most important prognostic factor for a client with breast cancer is:

Although tumor size is a factor in classification of cancer growth, it is not an indicator of lymph node spread. Axillary node status is the most important indicator for predicting how far the cancer has spread. If the lymph nodes are positive for cancer cells, the prognosis is poorer. The client's previous history of cancer puts her at an increased risk for breast cancer recurrence, especially if the cancer occurred in the other breast. It does not predict prognosis, however. The estrogen-progesterone assay test is used to identify present tumors being fed from an estrogen site within the body. Some breast cancers grow rapidly as long as there is an estrogen supply such as from the ovaries. The estrogen-progesterone assay test does not indicate the prognosis.