Tubular adenoma of the breast

Last revised by Calum Worsley on 14 Mar 2024

Tubular adenomas (TA) of the breast, also known as pure adenoma of the breast, are a rare benign breast lesion. It is a type of adenomatous breast lesion.

They are typically found in young women and are usually palpated by the patient or her physician.

Tubular adenomas are rare tumors of the breast, that account for only 0.13–1.7% of benign breast lesions 5. The patient age ranges between 13-76 years; however, the lesions are seen most commonly in young females, with greater than 90% cases being discovered in females below the age of 40 years (mean age=31 years) 5. Rarely, they have also been reported in male patients. The lesion size ranges from 1.0 cm to more than 7.5 cm but is barely greater than 5 cm 5.

On gross pathology, tubular adenomas appear as circumscribed masses. Microscopically, they contain closely-approximated tubular structures that vary little in size. These lesions are related to fibroadenomas but can be distinguished by the predominance of epithelium and relative lack of stromal components.

While they can a variable appearance, they are typically seen as non-calcified round or oval masses with either well-defined or obscure margin. Because the lesions are typically found in young women, primary imaging is almost always with ultrasound.

In young females, no calcifications are seen in the tubular adenomas and they closely resemble non-calcified fibroadenomas; however, calcifications (irregular or tightly packed punctate) may be seen in older patients, which need tissue diagnosis to rule out the possibility of malignancy. Rarely, the lesions may exhibit ill-defined margins 5.

There is significant sonographic imaging overlap with fibroadenoma and differentiation can be impossible. They are typically seen as well defined hypoechoic lesions with relatively well-defined margins. There may be posterior acoustic enhancement.

In practice, these lesions are exceptionally rare. Typically the lesion is expected to likely be a fibroadenoma on biopsy and the diagnosis comes as a bit of a surprise when you get back the histology report. These lesions very rarely show calcification and are almost unknown in postmenopausal women.

ADVERTISEMENT: Supporters see fewer/no ads