Value of two-dimensional ultrasound and shear wave elastography in the evaluation of lymphedema associated with breast cancer

Objective To explore the application value of two-dimensional ultrasound and shear wave elastography (SWE) in diagnosing breast cancer-related lymphedema (BCRL) and evaluating the efficacy on rehabilitation.

Methods According to the clinical assessment, a total of 102 patients were divided into normal group, subclinical lymphedema group and clinical lymphedema group. Two-dimensional ultrasoundand SWE were used to detect the skin and subcutaneous tissue of the upper limbs of the patients, and the corresponding thickness and hardness were obtained. The correlations of the thickness and hardness of the skin and subcutaneous tissue of the patients in the edema group(subclinical lymphedema group and clinical lymphedema group) with the International Society of Lymphology(ISL)classification were analyzed. The thickness and hardness of skin and subcutaneous tissue of affected limb and contralateral limb in the three groups were compared. The value of circumferential diameter measurement, two dimensional ultrasound and SWE in evaluating therapeutic effect was compared.

Results In subclinical lymphedema group, the skin thickness, hardness and subcutaneous tissue hardness ofthe forearm of the affected limb were greater than those of the opposite limb (P < 0.05). The skin and subcutaneous tissue thickness and hardness ofthe forearm and upper arm of the affected limb in the clinical lymphedema group were significantly greater than those of the contralateral limb (P < 0.05); forearm skin thickness (r=0.443, P < 0.001) and forearm skin hardness (r=0.275, P=0.024) in the edema group were significantly positively correlated with ISL stage. The receiver operating characteristic curve showed that the area under the curve of two-dimensional ultrasound and SWE in diagnosis of subclinical BCRL was 0.808 and 0.934, respectively. the differences between the two-dimensional ultrasound and SWE assessment of the subclinical lymphedema group before and after treatment were statistically significant (P < 0.05). There was no significant difference in the assessment results of circumference measurement before and after treatment (P=0.293).

Conclusion Two-dimensional ultrasound and SWE are both of high value for the diagnosis and assessment of treatment effects of BCRL; in early diagnosis, the diagnostic efficacy of SWE is better than that of two-dimensional ultrasound.