Role of Ultrasound in Pretreatment Evaluation of Lymph Node Status in Carcinoma Breast: A Systematic Review

Aim: This systematic review aimed to analyze efficacy of axillary ultrasonography (USG) in differentiating normal from abnormal lymph nodes (LNs) in breast cancer patients, taking into account the different criteria used. Background: Identification of pretreatment axillary LN metastasis is one of the most important prognostic factors in breast cancer, and it affects the surgical plan and oncological management after surgery. Review results: A PubMed search was made using the following items: “Ultrasonography” [Mesh] AND “Axilla” [Mesh] AND “Breast Neoplasms” [Mesh]. A total of 34 studies were included in the review analysis. Studies were divided according to the LN feature studied into six subheadings which include size, cortex thickness, hilum changes, long axis-to-short axis ratio (L/S ratio), combination of multiple morphological factors, and combination of both morphology and size. For LN size, sensitivity and specificity ranged from 49 to 95%, 34 to 97.4%; cortical thickness 35 to 96%, 36 to 92%; hilar changes 24 to 92%, 23 to 100%; L/S ratio 65 to 100%, 18 to 65%; morphological features 26 to 94%, 76 to 100%; and combination of both morphological and size 18 to 100%, 50 to 100%, respectively. Conclusion: Role of USG in pretreatment axillary staging has been extensively studied. Various diagnostic criteria have been used for defining abnormal LN, which leads to difficult comparisons between various studies. Clinical significance: Pretreatment evaluation of axilla with USG, using multiple criteria, like LN size, L/S ratio, cortical, and hilar abnormalities in combination with morphological features, gave the best accuracy for detection of abnormal nodes and lowest false-negative rates in breast cancer patients.