Humpath.com - Human pathology

Home > E. Pathology by systems > Reproductive system > Female genital system > Breast > ductal hyperplasia

ductal hyperplasia

Wednesday 18 March 2015

mammary ductal hyperplasia; ductal hyperplasia of the breast

WebPath PO

Synopsis

- Proliferating cells form solid sheets, irregular glandular spaces and papillary projections.
- Proliferating cells form sieve-like spaces, so called cribriform pattern.
- In ductal hyperplasia without nuclear atypia, the proliferating cells consists of secretory cells with round to oval nuclei.
- Myoepithelial cells have oval to elongated, slightly hyperchromatic nuclei.
- Mild ductal hyperplasia is three or four cell layers thick.
- The nuclei are normochromatic, oval, with inconspicuous nucleoli and no mitotic activity.
- papillary ductal hyperplasia

  • Papillary hyperplasia is part of the spectrum of mild and moderate ductal hyperplasia.
  • The papillae are blunt or delicate and irregularly shaped.
  • Intraluminal proliferation may create a solid ball of epithelium attached to one side of the duct and surrounded by a cleft-like space - creating an appearance reminiscent of a renal glomerulus.

- In florid ductal hyperplasia with apocrine change, the individual cells have abundant granular eosinophilic cytoplasm and distinct cytoplasmic borders.

- The entire lumen can be filled up by the proliferating ductal epithelial cells.

  • The nuclei are oval and normochromatic and mitotic activity is not increased.
  • There is no necrosis.
  • Several elongated clefts can be present at the periphery and within the cluster.
  • There is some streaming effect due to oval nuclei being aligned in parallel bundles.

- In florid ductal hyperplasia, there can be several peripheral elongated clefts.

  • They are bound on one side by basally located cells and on the other side by solid intraluminal cluster of epithelal cells.

Differential diagnosis

- mammary atypical ductal hyperplasia

  • The proliferating cells form irregular glandular spaces.
  • Atypical cells with enlarged, irregular, hyperchromatic nuclei, uneven distribution of chromatin, and medium sized nucleoli.
  • Individually, these atypical cells have the characters of malignant cells. However, the background benign epithelial cells and myoepithelial cells remain.
  • In these foci, highly atypical cells can become quite homogeneous, however, rare myoepithelial cells with small, dark nuclei remain.
  • Solid filling of a duct can be observed.
  • In patient with atypical ductal hyperplasia, the risk of invasive breast carcinoma is approximately 5 times that of the general population.
  • The cytologic features are indistinguishable from low-grade DCIS (monomorphic cells with round or oval nuclei, micropapillary structures, tufts, fronds, cribriform areas etc).
  • But usually they are admixed with ductal hyperplasia or show partial involvement of terminal duct-lobular unit.