A solid mass with posterior acoustic enhancement on ultrasound is most consistent with which lesion?

A solid mass with posterior acoustic enhancement on ultrasound is most consistent with which lesion?

• A. Adenocarcinoma
• B. Serous cystadenoma
• C. Adenoma
• D. Mucinous cystadenoma

Answer: (C)

Posterior acoustic enhancement happens when the structure has very low attenuation, letting more ultrasound energy pass through and making the tissue behind it appear brighter. This is a hallmark of cystic or fluid-filled lesions, but a solid mass can also show enhancement if its interior attenuates less than surrounding tissue. Among the given options, two are cystic lesions and would typically appear fluid-filled on ultrasound, which would fit the enhancement pattern but not a solid mass description. A malignant adenocarcinoma is more likely to display irregular margins and possibly other suspicious features rather than a clean posterior enhancement behind a solid mass. An adenoma is a benign solid tumor, and when it is relatively non-attenuating, it can produce posterior acoustic enhancement behind it. Therefore, a solid mass with posterior acoustic enhancement aligns best with adenoma.

Posterior acoustic enhancement happens when the structure has very low attenuation, letting more ultrasound energy pass through and making the tissue behind it appear brighter. This is a hallmark of cystic or fluid-filled lesions, but a solid mass can also show enhancement if its interior attenuates less than surrounding tissue. Among the given options, two are cystic lesions and would typically appear fluid-filled on ultrasound, which would fit the enhancement pattern but not a solid mass description. A malignant adenocarcinoma is more likely to display irregular margins and possibly other suspicious features rather than a clean posterior enhancement behind a solid mass. An adenoma is a benign solid tumor, and when it is relatively non-attenuating, it can produce posterior acoustic enhancement behind it. Therefore, a solid mass with posterior acoustic enhancement aligns best with adenoma.