Causes of Avascular Hypoechoic Testicular Lesions Detected at Scrotal Ultrasound: Can They Be Considered Benign?

OBJECTIVE

The purposes of this study were to determine the cause of avascular hypoechoic lesions detected at scrotal ultrasound and to assess usefulness of sonographic and clinical features in differentiating benign from malignant etiologic factors.

MATERIALS AND METHODS

This retrospective study included 58 patients with avascular hypoechoic lesions detected at testicular ultrasound. The sonographic features recorded were lesion size and margins and presence of peripheral vascularity and focal calcifications. Also recorded were patient age, symptoms, risk factors, lesion palpability, and levels of serum tumor markers. The reference standard was pathologic results or at least 2-year stability documented with serial follow-up ultrasound studies. Features associated with malignant, including burnt-out, lesions and benign lesions were examined by Fisher exact test, Wilcox-on rank sum test, and the generalized estimating equations method for multivariable models.

RESULTS

Sixty-three lesions were identified in 58 patients; 40 of the 63 (63.5%) were benign. Patients with malignant lesions had elevated serum tumor marker levels more often than patients who had benign lesions (26.1% versus 5.7%, p = 0.043). The clinical palpability of lesions and history of testicular cancer were not statistically significantly different between patients with malignant and those with benign lesions. Poorly defined margins of a lesion and focal calcification within the lesion were more often found in malignant lesions. Maximal size of a lesion and peripheral vascularity were not associated with either the benign or the malignant nature of a lesion.

CONCLUSION

Although most avascular hypoechoic testicular lesions are benign, a substantial proportion are malignant. The ultrasound characteristics of a lesion, the patient's clinical presentation, and serum tumor marker status may be useful in differentiating malignant from benign lesions.