Breast cytopathology
Breast cytopathology is a relatively small part of cytopathology, as core biopsies are more in style.
This article deals only with breast cytopathology. An introduction to cytopathology is in the cytopathology article.
Overview
Common indications
- FNA done for a clinically benign lesion - unusual to find malignancy.
- FNA of a satellite lesion to assess extent of a presumed cancer; done together with a core biopsy of another site.
Pitfalls
False negative:
- Lobular carcinoma - often single cells (may be in "chains"/"single file"), slightly hypercellular, cells appear bland/normal cytologically (if not carefully examined).[1]
Malignancy - the short version
Normal
Features:
- Sheets of flat cells.
- Usu. no nucleoli.
- Stripped bipolar (elliptical) nuclei.
- +/-Adipose tissue:
- Peripheral nucleus.
- One large vacuole.
Notes:
- Adipose tissue may represent a lipoma.
Breast cytopathology in a table
The common entities in breast cytopathology and their features:
Entity | Key feature | Architecture | Cells | Images |
---|---|---|---|---|
Normal | Flat sheets of cells, stripped bipolar nuclei | Flat sheets | Uniform size, lack nucleolus | |
Fibroepithelial lesion (fibroadenoma, phyllodes) | Clusters of cells with staghorn shape (jagged edge), bare bipolar nuclei | Flat sheets & fluffy paucicellular (fibrous) tissue | Mixed pop. in cluster; nuclei: oval/spindle (myoepi.) and round (epi.). | Fibroadenoma - FNA (WC), Fibroadenoma FNA - Diff-Quik (WC), Fibroadenoma (flickr.com) |
Fibrocystic change | Macrophages | May have flat sheets of cells | Oncocytic change (apocrine change) common, histocytes (foamy cytoplasm), nucleoli, large NCR | Oncocytes in FCC (WC) |
Papillary neoplasm | Stalks (fibrovascular cores) | Sheets, usu. flat? | Variable size, nucleolus | Papillary neoplasm (WC) |
Ductal carcinoma | Nuclear atypia, lack of stripped bipolar nuclei | 3-D clusters | Nuclear size variation, membrane irreg., nucleoli (prominent) - every cell, cell size var. | Ductal carcinoma - animation showing 3-D nature (WC) |
Fat necrosis
Microscopic
Features:[4]
- Dying/dead adipocytes:
- Light pink "low density" whispy poorly demarcated blobs - lack a nucleus.
- Early: cellular outlines seen, light pink - loose.
- Mid: adipocytes collapsed/more dense.
- Foamy macrophages - adjacent to fat.
- Abundant cytoplasm - with granular (pink) crap inside.
- Oval nucleus with small nucleolus.
- Foamy macrophages - adjacent to fat.
- Late:
- Macrophages: multinucleated giant-cells.
- Calcification.
- Light pink "low density" whispy poorly demarcated blobs - lack a nucleus.
Notes:
- Healthy adipocytes - large cells, clear cytoplasm.
Images:
Adenocarcinoma
- By convention one usually calls everything ductal carcinoma.
Cytopathology
Five features:[5]
- Cellular size variation.
- Nuclear size variation.
- May be marked adjacent cells different by factor of 2.
- Typically not marked - often ~1.5.
- Nucleoli.
- Should be in every cell.
- Multiple suggestive of malignant.
- Irregular chromatin pattern.
- Lack of singular bipolar nuclei (in the background), key negative.
Other features:
- 3-D clusters - strong indicator.
- Cytoplasmic vacuoles - considered a classic finding.
Notes:
- Typically single cells present.[6]
- Exceptions are tubular carcinoma and colloid carcinoma; these have cells found in clusters or tubules/glands.[1]
- Intracytoplasmic "lumens"/inclusions (think lobular carcinoma).
Images:
Fibroadenoma
Features:[7]
- Flat sheet of cells with mixed population - key feature:
- Cells with round nuclei (epithelium).
- Cells with oval nuclei (myoepithelium).
- Stromal fragments:
- Spindle cells.
- Fluffy appearance - relatively paucicellular.
Images:
Apocrine metaplasia/fibrocystic changes
Features:[8]
- Architecture - pretty much anything (flat, single, papillary, clusters, sheets).
- Oncocytic change:
- Finely granular cytoplasm - key feature.
- Well-defined cell borders.
- Nuclei round typically with one nucleolus (occasionally several nucleoli).
- Macrophages (foamy) - key feature.
- Vacuolated cytoplasm + round/oval nuclei.
Image:
Paget's disease
Main article: Paget disease of the breast
Features:[8]
- Usually large cells with:
- Nuclear atypia and nucleolus.
- Abundant bubby (vacuolated) cytoplasm.
- Malignant cell may have "cell-in-cell" arrangement.
Papillary neoplasm
Features:
- Fibrovascular core - key feature.
Image:
See also
References
- ↑ 1.0 1.1 Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 678. ISBN 978-1416025887.
- ↑ SM. 12 January 2010.
- ↑ SB. 27 January 2010.
- ↑ Taboada, JL.; Stephens, TW.; Krishnamurthy, S.; Brandt, KR.; Whitman, GJ. (Mar 2009). "The many faces of fat necrosis in the breast.". AJR Am J Roentgenol 192 (3): 815-25. doi:10.2214/AJR.08.1250. PMID 19234281.
- ↑ Foundations Series - FNA book.
- ↑ Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 678 (Q16). ISBN 978-1416025887.
- ↑ Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 676. ISBN 978-1416025887.
- ↑ 8.0 8.1 Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 677. ISBN 978-1416025887.