Can the Memorial Sloan-Kettering Cancer Center nomogram predict the likelihood of nonsentinel lymph node metastases in breast cancer patients in the Netherlands?

BACKGROUND: According to Dutch guidelines, an axillary lymph node dissection (ALND) is recommended whenever a sentinel lymph node (SLN) contains metastatic disease. However, only in approximately 50% of patients with metastatic disease in the SLN are additional nodal metastases detected in the completion ALND. To identify the individual patient's risk for non-SLN metastases, a nomogram containing eight predictors was developed by the Breast Service of Memorial Sloan-Kettering Cancer Center (New York, NY). The aim of this study was to test the accuracy of the nomogram on a population of Dutch breast cancer patients. METHODS: Patient, tumor, and SLN metastasis characteristics were collected for 222 consecutive patients who underwent a completion ALND. The data of the index and test populations were compared. A receiver operating characteristic curve was drawn, and the area under the curve was calculated to assess the discriminative power of the nomogram. RESULTS: Even though our patient population differed in many respects from the source population, the area under the receiver operating characteristic curve amounted to .77, a value very much comparable to the one found in the source population. CONCLUSIONS: The nomogram provides a fairly accurate predicted probability for the likelihood of non-SLN metastases in a general population of breast cancer patients at a regional teaching hospital in The Netherlands. This suggests that the nomogram's originally calculated predictive accuracy may be valid for patient populations that differ considerably from the population in which it was developed.

Axillary recurrence after a negative sentinel node biopsy for breast cancer: incidence and clinical significance.

BACKGROUND: Sentinel lymph node biopsy (SLNB) carries the inherent risk of approximately 5% false-negative sampling. Undetected tumor-positive nodes of clinical importance are those that lead to axillary recurrence. This survey aims at clarifying the extent of this problem in current practice and literature. METHODS: In a regional teaching hospital, 696 consecutive breast cancer patients underwent SLNB between January 1998 and July 2003, and data were entered in a prospective database. PubMed and the Cochrane library were searched for a systematic review of the literature. Thirteen studies dealt with the follow-up of a cohort of sentinel lymph node (SLN)-negative patients or presented a case report. RESULTS: The SLN identification rate was 97.1%. The SLN was tumor free in 439 (65%) of the 676 patients. After a median follow-up of 26 months, axillary recurrence was detected in 2 of 439 patients 4 and 27 months after the SLNB. The incidence of clinically apparent false-negative SLNB is .46%. The systematic review resulted in 3184 SLNB-negative patients with a median follow-up of 25 months. Axillary recurrence occurred in eight patients after a median of 21 months. The axillary recurrence rate in the literature is .25%. One third of these patients present with synchronous systemic metastases. CONCLUSIONS: Axillary recurrences after a negative SLNB occur, but at a much lower rate than would be expected on the basis of historical figures and the false-negative SLN findings. The natural history of axillary relapse after negative SLNB resembles the locoregional recurrence of breast cancer.