Can surgical oncologists reliably predict the likelihood for non-SLN metastases in breast cancer patients?
BACKGROUND
In approximately 40% of the breast cancer patients with sentinel lymph node (SLN) metastases, additional nodal metastases are detected in the completion axillary lymph node dissection (cALND). The MSKCC nomogram can help to quantify a patient's individual risk for non-SLN metastases with fairly accurate predicted probability. The aim of this study was to compare the predictions of surgical oncologists for non-SLN metastases with nomogram results and to clarify the impact of nomogram results on clinical decision-making.


METHODS
Questionnaires, containing patient scenarios, were sent to surgical oncologists involved in breast cancer care. The surgeon was asked to predict the probability for non-SLN metastases for the first five scenarios. For the remaining scenarios, the patient's actuarial likelihood, calculated by the nomogram, was supplied. The surgeon was asked whether or not (s)he would perform a cALND. The type of hospital and the surgeon's experience were registered.


RESULTS
The concordance-index amounted to 0.78, indicating moderate concurrence between the surgical predictions and nomogram results. The intersurgeon variation was important. About 25% of the surgeons was influenced by nomogram information and decided in one or more patients to abandon the cALND. Neither the type of hospital nor experience influenced predicting abilities or the clinical decision-making process.


CONCLUSIONS
Individual predictions of surgical oncologists for non-SLN metastases do not correlate well with the MSKCC nomogram. The distribution between intersurgeon predictions for one scenario is important. Therefore, the nomogram is superior to clinical estimations for predicting the likelihood for non-SLN metastases.
Smidt
Marjolein L
ML
Department of Surgical Oncology, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands. marjoleinsmidt@yahoo.com
Strobbe
Luc J A
LJ
Groenewoud
Hans M M
HM
der Wilt
Gert Jan
GJ
Van Zee
Kimberley J
KJ
Wobbes
Theo
T
D001365:Axilla; D001943:Breast Neoplasms / Q000473:pathology*; D005260:Female; D013502:General Surgery; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D049451:Nomograms; D011237:Predictive Value of Tests; D011336:Probability; D012306:Risk; D021701:Sentinel Lymph Node Biopsy