The terminal ductal lobular units (TDLUs) are the functional units of the breast. The TDLU consists of the extralobular terminal ducts and intralobular terminal ducts. The intralobular terminal ducts form the central space of the lobule and have multiple outpouchings called acini or ductules. The ductules differentiate into the secretory units during lactation. Intralobular stroma surrounds the lobules.
Adenosis involves the epithelial and myoepithelial cells of the ductules.
Solitary (central) papillomas originate in the large ducts (segmental or subsegmental), but do not involve the TDLU. On the other hand multiple (peripheral) papillomas have a root in the TDLU and spread into the large ducts.
Cysts arise in the lobule, where the acini dilate, unfold, and then enlarge as fluid-filled cysts.
References
- Bassett LW et al. Breast Disease. Test and Syllabus. ACR (2000). p 14.
- Ohuchi N, Abe R, Takahashi T, Tezuka F. Origin and extension of intraductal papillomas of the breast: a three-dimensional reconstruction study. Breast Cancer Res Treat. 1984;4(2):117-28.
nice, thx.
ReplyDeletenice indeed .. thx
ReplyDeleteMany thanks, that really helped me. I was so confused about TDLUs. Now, very clear!
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