Axillary lymph node status

This variable indicates whether axillary lymph node metastases were detected at the time of the first diagnosis of breast cancer. The nodal status was recorded according to the TNM Classification of Malignant Tumours (1). For the purpose of the present website the following categories were added to the drop-down-list:

negative = no regional lymph node metastases found
positive = one or more axillary or ipsilateral internal mammary lymph node metastases were present at the time of the diagnosis

1-3 pos = metastasis to 1-3 lymph nodes detected
4-9 pos = metastasis to 4-9 lymph nodes detected
>=10 pos = metastasis to  10 or more lymph nodes detected
not available = missing data or the nodes could not be assessed

Note 1: Lymph node metastasis was coded as a distant metastasis (M1) if supraclavicular, cervical, or contralateral internal mammary lymph nodes were involved. These patients were excluded from the current data set as described in "exclusion criteria".

1. TNM Classification of Malignant Tumours, fifth edition, L.H. Sobin and C. Wittekind (Eds), John Wiley & Sons, Inc., New York, 1997, pp. 227.