title: Nomogram including the total tumoral load in the sentinel nodes assessed by one-step nucleic acid amplification as a new factor for predicting nonsentinel lymph node metastasis in breast cancer patients.
abstract: Several models have been developed to predict non-sentinel nodes (NSLN) metastasis in patients with a positive sentinel node (SLN) that incorporates a standard pathology examination of the SLN. It has been reported that total tumoral load (TTL) in the SLNs assessed by one-step nucleic acid amplification (OSNA) is a predictive factor for additional NSLN metastasis in the axillary lymph node dissection (ALND). The objective was to develop a nomogram that predicts patient´s risk of additional NSLN metastasis incorporating TTL in the SLNs assessed by OSNA. Six hundred and ninety-seven consecutive patients with positive SLN evaluation by OSNA and a completion ALND were recruited. Pathologic features of the primary tumor and SLN metastases, including TTL were collected. Multivariate logistic regression identified factors predictive of non-SLN metastasis. A nomogram was developed with these variables and validated in an external cohort. On multivariate logistic regression analysis, tumor size, number of affected SLN, Her2 overexpression, lymphovascular invasion, and TTL were each associated with the likelihood of additional NSLN metastasis (p < 0.05). The overall predictive accuracy of the nomogram, as measured by the AUC was 0.7552 (95 %CI 0.7159-0.7945). When applied to the external cohort the nomogram was accurate with an AUC = 0.678 (95 %CI 0.621-0.736). This novel nomogram that incorporates TTL assessed by OSNA performs well and may help clinicians to make decisions about ALND for individual patients. Moreover, the standardization of pathologic assessment by OSNA may help to achieve interinstitutional reproducibility among nomograms.
authors.affiliation: Breast Surgical Oncology Unit, Hospital Universitario Vall d´Hebron, Universitat Autònoma de Barcelona, 119, 08035, Barcelona, Spain, irubio@vhio.net.
authors.forename: Isabel T
authors.initials: IT
authors.lastname: Rubio
authors.forename: Martin
authors.initials: M
authors.lastname: Espinosa-Bravo
authors.forename: Maxi
authors.initials: M
authors.lastname: Rodrigo
authors.forename: Maria
authors.initials: M
authors.lastname: Amparo Viguri Diaz
authors.forename: David
authors.initials: D
authors.lastname: Hardisson
authors.forename: Amaia
authors.initials: A
authors.lastname: Sagasta
authors.forename: Basilio
authors.initials: B
authors.lastname: Dueñas
authors.forename: Vicente
authors.initials: V
authors.lastname: Peg
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D049451:Nomograms; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D015203:Reproducibility of Results; D021701:Sentinel Lymph Node Biopsy / Q000379:methods; D047368:Tumor Burden