Validation of a breast cancer nomogram for predicting nonsentinel node metastases after minimal sentinel node involvement: validation of the Helsinki breast nomogram

Abstract

Background: Complete node dissection for tumor-positive sentinel lymph nodes (SLN) is becoming more controversial. Nevertheless, current practice guidelines still recommend complete axillary lymph node dissection (ALND) for breast cancer patients whose SLN contains a metastatic tumor. The Helsinki breast cancer nomogram developed by Meretoja TJ et al. aims to predict the risk of positive non-sentinel lymph nodes in patients with minimal sentinel node involvement, it uses tumor diameter and multifocality. The purpose of this study was to test the accuracy of the nomogram among patients with micrometastatic SLN-positive biopsy findings.

Methods: The Helsinki nomogram was used to calculate risk of metastases for 49 consecutive patients with SLN micrometastases or isolated tumor cells (ITC) who underwent complete ALND. The nomogram was evaluated by calculating the area under the receiver-operator characteristic (ROC) curve.

Results: The area under the ROC curve for the nomogram applied to all patients with micrometastases and ITC was 0.72 (range 0.60-0.85) (0.791 in the original publication).

Conclusions: The Helsinki breast cancer nomogram is a useful tool for patients with minimal sentinel node involvement.

Keywords: Breast cancer; Isolated tumor cells; Micrometastasis; Nomogram; Nonsentinel node metastases; Sentinel lymph node.