Tag Archives: LCIS

Organ Systems, Breast

Lobular Carcinoma In Situ (LCIS)

Lobular Carcinoma In Situ (LCIS)
  • Neoplastic proliferation within ducts/lobules (fill and expand lobules)
  • Associated with loss of expression of E-Cadherin
  • Incidental finding (not associated with calcifications or stromal reactions found by mammography)
  • LCIS is bilateral 20-40% of cases
  • Morphology
    • Mucin-positive signet ring cells often present
    • E-Cadherin negative cells
    • Uniform cells with oval/round nuclei
    • Pagetoid spread (cells present between the myoepithelial layer and over lying luminal epithelium 
    • Typically ER/PR positive
    • Her-2 is not overexpressed
  • 1%/year risk of developing an invasive tumor (similar to low-grade DCIS) – Lifetime risk is ~25-35% (20-30 year time period)
  • Cancer risk is equal in contralateral breast (unlike DCIS)
  • Pleomorphic variant of LCIS
    • High grade nuclei
    • May be ER negative
    • Some may overexpress Her-2
    • May be separate entity from typical LCIS
Photomicrographs
Breast - Lobular Carcinoma In Situ (LCIS)

LCIS characterized by filling and expansion of the lobular unit.

Breast - Lobular Carcinoma In Situ (LCIS)
LCIS characterized by filling and expansion of the lobular unit.
Breast - Lobular Carcinoma In Situ (LCIS)
LCIS characterized by filling and expansion of the lobular unit.
References

Kumar, Vinay, Abul K. Abbas, and Jon C. Aster. Robbins and Cotran Pathologic Basis of Disease. Ninth edition. Philadelphia, PA: Elsevier/Saunders, 2015.  p. 1045.

Organ Systems, IHC Panels

Breast – DCIS vs. LCIS

Lobular vs. ductal differentiation in breast lesions can on occasion be problematic.  E-cadherin is well described as a marker of ductal differentiation, but aberrant expression has be reported in 2-16% of cases of lobular neoplasia.  Some authors suggest not changing the interpretation/diagnosis based on expression of E-cadherin is the morphology is consistent with lobular carcinoma.  This author is not sure why one would do the stain to begin with if the morphologic characteristics are consistent with lobular carcinoma.  34betaE12 (CK903) has been described as a sensitive and specific in showing perinuclear dot-like expression in cases of lobular carcinoma and negativity in ductal carcinomas.  The combined panel of 34betaE12 and E-cadherin makes a nice complimentary panel to evaluate between lobular and ductal differentiation in breast carcinomas when morphology alone is not clear.
 
IHC Stain
DCIS
LCIS
E-Cadherin
+
=
34betaE12
=
+
References
Liu H. Application of immunohistochemistry in breast pathology: a review and update. Arch Pathol Lab Med. 2014;138(12):1629–1642. doi:10.5858/arpa.2014-0094-RA.
 
Bratthauer GL, Moinfar F, Stamatakos MD, et al. Combined E-cadherin and high molecular weight cytokeratin immunoprofile differentiates lobular, ductal, and hybrid mammary intraepithelial neoplasias. Hum Pathol. 2002;33(6): 620–627.
Antibody List, A - F Antibodies

Calponin

Calponin is an actin filament and is expressed in smooth muscle.  It is often used individually or combined with other IHC markers to identify the myoepithelial layer in breast epithelium.  It is important to remember, like other smooth muscle markers, that myofibroblasts may also express calponin.  Therefore, care should be taken not to mistake myofibroblast positivity for myoepithelial positivity. 
 
It is also expressed in cases of collagenous spherulosis (positive), but not adenoid cystic carcinoma of the breast.  Calponin is not a specific stain, and has been identified in numbers pathologic disease processes.  It is recommended to refer to specific medical literature for the IHC performance based on the differential diagnosis.
 
Positive Expression:
  • Atypical fibroxanthoma (30%) [Virchows Arch 200;437:58]
  • Benign Fibrous Histiocytoma (65%)
  • Collagenous Spherulosis[Mod Path 2006;19:1351]
  • DFSP (40%)
  • Fibromatosis [Am J Dermatopathol 2006;28:105]
  • Fibrosarcoma (60%)
  • Glomus Tumor [AJSP 2002;26:301]
  • Leiomyoma
  • Leiomyosarcoma
  • MFH of bone (47%) [J Clin Pathol 2002;55:853]
  • MPNST (40%)
  • Myoepithelioma-skin
  • Solitary fibrous tumor (70%)
  • Synovial Sarcoma [Histopathology 2003;42:588]
  • Myofibroblastic lesions
Photomicorgraphs
Calponin - Pleomorphic Lobular Carcinoma of Breast
Calponin – Pleomorphic Lobular Carcinoma of Breast
Calponin - Pleomorphic Lobular Carcinoma of Breast
Calponin – Pleomorphic Lobular Carcinoma of Breast
Calponin - Pleomorphic Lobular Carcinoma of Breast
Calponin – Pleomorphic Lobular Carcinoma of Breast
References
Zhao L, Yang X, Khan A, Kandil D. Diagnostic role of immunohistochemistry in the evaluation of breast pathology specimens. Arch Pathol Lab Med. 2014;138: 16–24. doi:10.5858/arpa.2012-0440-RA
 
Dewar R, Fadare O, Gilmore H, Gown AM. Best practices in diagnostic immunohistochemistry: myoepithelial markers in breast pathology. Arch Pathol Lab Med. 2011;135: 422–429. doi:10.1043/2010-0336-CP.1
 
Werling RW, Hwang H, Yaziji H, Gown AM. Immunohistochemical distinction of invasive from noninvasive breast lesions: a comparative study of p63 versus calponin and smooth muscle myosin heavy chain. Am J Surg Pathol. 2003;27: 82–90. 
 
Liu H. Application of immunohistochemistry in breast pathology: a review and update. Arch Pathol Lab Med. 2014;138: 1629–1642. doi:10.5858/arpa.2014-0094-RA