Home   Chapter Home   Jobs   Conferences   Fellowships   Books

 

 

Advertisement 

 

Breast-nonmalignant

Benign tumors / changes

Phyllodes Tumor - Benign

 

Reviewer: Hind Nassar, M.D. in January 2009 (see Authors page)

Revised: 8 October 2012, last major update April 2010

Copyright: (c) 2002-2010, PathologyOutlines.com, Inc.

 

Definition

=========================================================================

● Phyllodes features but no/rare mitotic figures, no atypia,

 

Terminology

=========================================================================

● Also called low grade because even histologically benign appearing tumors may have malignant behavior

 

Epidemiology

=========================================================================

 

Sites

=========================================================================

 

Etiology

=========================================================================

 

Clinical features

=========================================================================

● Most (75%) phyllodes tumors are benign

● May have benign adipose tissue as primary stromal component (lipophyllodes tumor, Arch Pathol Lab Med 1994;118:91)

● May recur locally, but only rare distant metastases

 

Prognostic factors

=========================================================================

 

Case reports

=========================================================================

● Three synchronous tumors (Arch Pathol Lab Med 1990;114:624)

● With DCIS and LCIS (Arch Pathol Lab Med 1987;111:873)

● With same intracytoplasmic inclusion bodies as infantile digital fibromatosis (Am J Surg Pathol 1994;18:506)

 

Treatment

=========================================================================

● Excision with 1-2 cm margins (Mod Pathol 2001;14:185)

● Breast preservation if possible, particular in young women

 

Clinical images

=========================================================================

 

Gross description (Macroscopy)

=========================================================================

● Well circumscribed, firm, gray-white cut surface with cleft-like spaces resembling a leaf

● Variable cysts, hemorrhage, necrosis (more common in larger tumors)

 

Gross images

=========================================================================

 

         

Large, well circumscribed tumors

 

 

Multiple polypoid nodules separated

by cleft-like spaces

 

Micro description (Histopathology)

=========================================================================

● Circumscribed pushing border, stromal hypercellularity (particularly next to epithelial elements) and benign glandular elements with intracanalicular pattern, but ratio is balanced

● Stroma resembles fibroblasts and myofibroblasts

● Epithelial component has luminal epithelial cells resting on myoepithelial layer

● May exhibit hyperplasia, squamous metaplasia

● May have clusters of multinucleated giant cells (Arch Pathol Lab Med 1994;118:912)

● Variable hemorrhage, necrosis, fat, bone, cartilage and skeletal muscle

● 0-4 mitotic figures/10 HPF

● No atypia

 

Micro images

=========================================================================

 

            

Hyperplastic ducts surrounded by cellular fibrous stroma


                                               

Circumscribed tumor        Leaf like processes           Adjacent fibroadenoma

 

 

                                                               

Hyperplastic duct surrounded by                                   Well circumscribed tumor

cellular fibrous stroma                                                     with leaf-like ductal epithelium

 

 

                                               

Apocrine hyperplasia        Focal nuclear pleomorphism          With LCIS

and mitotic figures

 

 

               

CD117                       CD31

 

 

Ki-67

Fig A: benign tumor with minimal nuclear staining

Fig B: low grade malignant tumor with increased Ki-67

Fig C: high grade malignant tumor with frequent staining

 

Virtual Slides

=========================================================================

 

Videos

=========================================================================

 

Cytology description

=========================================================================

 

Cytology images

=========================================================================

 

Positive stains

=========================================================================

Epithelial cells:

● PR, GCDFP-15

 

Stromal cells:

● Vimentin, desmin, CD34, bcl2, ER-beta

● S100 (variable)

 

Negative stains

=========================================================================

 

Electron microscopy descriptions

=========================================================================

● Fibroblastic features

 

Electron microscopy images

=========================================================================

 

Molecular / cytogenetics description

=========================================================================

● No/few chromosome changes (Mod Pathol 2007;20:435)

● DNA content does not predict behavior (Hum Pathol 1992;23:1048)

 

Molecular / cytogenetics images

=========================================================================

 

 

Differential Diagnosis

=========================================================================

Cellular fibroadenoma: stroma less cellular than phyllodes, less stromal overgrowth, no atypia, fewer mitotic figures, less Ki-67 staining (Am J Clin Path 2005;124:342, Histopathology 2007;51:336)

Leiomyoma: smooth muscle morphology and immunohistochemistry

 

Additional references

=========================================================================

 

End of Breast-nonmalignant > Benign tumors / changes > Phyllodes tumor - benign

 

 

This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must also be interpreted in the context of a patient's clinical data using reasonable medical judgment.  This website should not be used as a substitute for the advice of a licensed physician.

 

All information on this website is protected by copyright of PathologyOutlines.com, Inc.  Information from third parties may also be protected by copyright.  Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).