Atypical ductal hyperplasia

Signs and symptoms

ADH, generally, is asymptomatic. It usually comes to medical attention on a screening mammogram, as a non-specific suspicious abnormality that requires a biopsy.

Pathology

ADH, cytologically, architecturally and on a molecular basis, is identical to a low-grade ductal carcinoma in situ (DCIS); however, it has a limited extent, i.e. is present in a very small amount ( Image:Atypical ductal hyperplasia - low mag.jpg | Low mag. Image:Atypical ductal hyperplasia - high mag.jpg | High mag.

Relation to low-grade ductal carcinoma in situ

While the histopathologic features and molecular features of ADH are that of (low-grade) DCIS, its clinical behaviour, unlike low-grade DCIS, is substantially better; thus, the more aggressive treatment for DCIS is not justified.

Diagnosis

It is diagnosed based on tissue, e.g. a biopsy, showing ductal hyperplasia.

There is no single definite cutoff that separates atypical ductal hyperplasia from ductal carcinoma in situ, but the following are important distinctive features of atypical ductal hyperplasia, with suggested cutoffs:

• Size less than 2 mm.
• Not involving more than one duct.
• The atypical epithelial proliferation is admixed with a second population of proliferative cells without atypia.
• The proliferation completely involves the terminal ductal lobular unit(s), to a limited extent.

Treatment

ADH, if found on a surgical (excisional) biopsy of a mammographic abnormality, does not require any further treatment, only mammographic follow-up.

If ADH is found on a core (needle) biopsy (a procedure which generally does not excise a suspicious mammographic abnormality), a surgical biopsy, i.e. a breast lumpectomy, to completely excise the abnormality and exclude breast cancer is the typical recommendation.

Prognosis

Cancer risk for ADH on a core biopsy

The rate at which breast cancer (ductal carcinoma in situ or invasive mammary carcinoma (all breast cancer except DCIS and LCIS)) is found at the time of a surgical (excisional) biopsy, following the diagnosis of ADH on a core (needle) biopsy varies considerably from hospital-to-hospital (range 4-54%). In two large studies, the conversion of an ADH on core biopsy to breast cancer on surgical excision, known as "up-grading", is approximately 30%.

Cancer risk based on follow-up

The relative risk of breast cancer based on a median follow-up of 8 years, in a case control study of US registered nurses, is 3.7.

References

References

1. "Understanding Breast Changes - National Cancer Institute".
2. (May 1995). "Atypical ductal hyperplasia diagnosed at stereotaxic core biopsy of breast lesions: an indication for surgical biopsy". AJR Am J Roentgenol.
3. (Dec 2006). "Discrepancies in the diagnosis of intraductal proliferative lesions of the breast and its management implications: results of a multinational survey". Virchows Arch.
4. (2018). "Atypical ductal hyperplasia and the risk of underestimation: tissue sampling method, multifocality, and associated calcification significantly influence the diagnostic upgrade rate based on subsequent surgical specimens". Breast Cancer.
5. (January 2009). "Frequency and upgrade rates of atypical ductal hyperplasia diagnosed at stereotactic vacuum-assisted breast biopsy: 9-versus 11-gauge". AJR Am J Roentgenol.
6. (2016). "Atypical Ductal Hyperplasia Bordering on Ductal Carcinoma In Situ". International Journal of Surgical Pathology.
7. (Feb 2011). "Factors associated with upgrading to malignancy at surgery of atypical ductal hyperplasia diagnosed on core biopsy". Breast.
8. (Oct 2006). "Correlation between core biopsy and excisional biopsy in breast high-risk lesions". Am J Surg.
9. (Feb 1992). "A prospective study of benign breast disease and the risk of breast cancer". JAMA.