Ultrasound evaluation of cervical lymphadenopathy: Can it reduce the need of histopathology/cytopathology?

Background: The differentiation between the causes of cervical lymphadenopathy is of paramount importance as these have different modalities of treatment with varying prognosis. The aim of this study was to evaluate the efficacy of B Mode and colour Doppler ultrasound (CDUS) to differentiate between benign and metastatic lymph nodes.

Methods: 100 patients of clinically palpable lymph nodes were evaluated with B Mode and CDUS. B Mode assessment included short-long (S:L) axis ratio, hilum, nodal border, echogenicity, intranodal necrosis and ancillary features. CDUS assessment included distribution of vascularity, resistive index (RI) and pulsatility index (PI). Statistical analysis was carried out with histopathological or cytological diagnosis as gold standard.

Results: B-Mode US correctly diagnosed 22/25 (88%) of the reactive lymph nodes giving it a sensitivity of 88% and specificity of 97.3%. Colour Doppler US diagnosed 23/25 (92%) reactive lymph nodes with a sensitivity of 92% and specificity of 97.3%. B-Mode underdiagnosed one case each of granulomatous disease and metastasis as reactive node while CDUS missed out two cases of granulomatous disease as reactive lymph node.

Conclusion: Individual parameters of B Mode when used alone were not found to be very effective in differentiating benign and malignant lymph nodes. However features of B-Mode combined together as well as color Doppler ultrasound, help in the detection of reactive lymph nodes and can be used as a diagnostic tool with good accuracy. However, they cannot be used as a diagnostic method for metastatic or tubercular nodes and cytopathology/histopathology remains the gold standard in such situations.