Breast cancer classification: Difference between revisions

Jump to navigation Jump to search
VisualWikitext
 
(42 intermediate revisions by 9 users not shown)
Line 1: Line 1:
__NOTOC__
{{Breast cancer}}
{{Breast cancer}}
{{CMG}}, '''Assistant Editor(s)-In-Chief:''' [[User:Jack Khouri|Jack Khouri]]
{{CMG}} {{AE}} {{MGS}} {{Soroush}}
 
==Overview==
==Overview==
'''Breast cancer classification''' divides all forms of [[breast cancer]] according to four different schemes, each based on different criteria and serving a different purpose. The four approaches consider pathology, the grade of the tumor, expression of proteins and genes, and the stage of the tumor.
Breast cancer may be classified according to anatomy into 4 subtypes: ductal, lobular, sarcoma, and lymphoma. There are also other methods of classification such as classification based on gene expression, and classification based on hormone receptors present. In practice, a combination of all above mentioned classification is combined with the surgical characteristics of tumors and radiologic findings is being applied for patient management, treatment planning, and prognosis determination.
 
==Classification based on histopathology==
Classifications of breast cancer are usually, but not always, classified by the histological appearance of tissue in the tumor.  Rare variants are defined on the basis of [[physical exam]] findings. For example, [[Inflammatory breast cancer]] (IBC), a form of ductal carcinoma or malignant cancer in the ducts, is distinguished from other [[carcinoma]]s by the [[inflammation|inflamed]] appearance of the affected breast.<ref>{{cite journal |author=Giordano SH, Hortobagyi GN |title=Inflammatory breast cancer: clinical progress and the main problems that must be addressed |journal=Breast Cancer Res. |volume=5 |issue=6 |pages=284–8 |year=2003 |pmid=14580242 |doi=10.1186/bcr608}} [http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=14580242 Free Full Text].</ref> In the future, some pathologic classifications may be changed. For example, a subset of ductal carcinomas may be re-named [[basal-like carcinoma]] (part of the [[Triple Negative Breast Cancer|"triple-negative" tumors]]).
===Malignant Tumors===
 
{| style="border: 0px; font-size: 90%; margin: 3px; width: 800px"
==Major Schemes==
| valign="top" |
*[[Pathology]] - A [[surgical pathology|pathologist]] will categorize each tumor based on its [[Histology|histological]] (microscopic anatomy) appearance and other criteria. The most common pathologic types of breast cancer are invasive [[ductal carcinoma]], [[malignant]] cancer in the breast's [[Duct (anatomy)|ducts]], and invasive lobular carcinoma, malignant cancer in the breast's [[Lobe (anatomy)|lobules]].
|+
*[[Bloom-Richardson grade|Grade of tumor]] - The histological grade of a [[tumor]] is determined by a pathologist under a microscope. A ''well-differentiated'' (low grade) tumor resembles normal tissue. A ''poorly differentiated'' (high grade) tumor is composed of disorganized cells and, therefore, does not look like normal tissue. ''Moderately differentiated'' (intermediate grade) tumors are somewhere in between.
! style="background: #4479BA; width: 150px;" | {{fontcolor|#FFF|Type}}
*[[Protein expression|Protein]] & [[gene expression]] status - Currently, all breast cancers should be tested for expression, or detectable effect, of the [[estrogen receptor]] (ER), [[progesterone receptor]] (PR) and [[HER2/neu]] proteins. These tests are usually done by [[immunohistochemistry]] and are presented in a pathologist's report. The profile of expression of a given tumor helps predict its [[prognosis]], or outlook, and helps an [[oncology|oncologist]] choose the most appropriate treatment. More genes and/or proteins may be tested in the future (eg [[PAX2]]<ref>http://cordis.europa.eu/fetch?CALLER=EN_NEWS&ACTION=D&SESSION=&RCN=30093</ref>).
! style="background: #4479BA; width: 300px;" | {{fontcolor|#FFF|Subtype}}
*Stage of a tumor - The currently accepted staging scheme for breast cancer is the [[TNM classification]].
|-
 
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
==Staging==
'''Ductal'''
[[Tumor|'''T'''umor]] - There are five tumor classification values (Tis, T1, T2, T3 or T4) which depend on the presence or absence of invasive cancer, the dimensions of the invasive cancer, and the presence or absence of invasion outside of the breast (e.g. to the skin of the breast, to the muscle or to the rib cage underneath):
| style="padding: 5px 5px; background: #F5F5F5;" |
*Tx - Primary tumor cannot be assessed.
*[[Ductal carcinoma in situ]] (DCIS)<ref name="class">Breast Neoplasm. Radiopedia. (2015) http://radiopaedia.org/articles/breast-neoplasms Accessed on March 1, 2019</ref>
*T0 - No evidence of primary tumor.
:*Comedo type: ~60%
*Tis - Carcinoma in situ.
:*Non-comedo type: ~40%
** Tis([[Ductal carcinoma|DCIS]]) - Intraductal Carcinoma in situ.
::*Papillary
** Tis(LCIS) - Lobular Carcinoma in situ.
::*Micropapillary
** Tis(Paget's) - [[Paget's disease of the breast|Paget's disease]] of the nipple with no tumor.
::*Cribriform
* T1 - Tumor 2cm or less in its greatest dimension.
::*Solid
** T1mic - Microinvasion 0.1cm or less in greatest dimension.
:*Intracystic papillary [[carcinoma]] in situ
** T1a - Tumor more than 0.1cm but not more than 0.5cm in its greatest dimension.
*Invasive ductal [[carcinoma]]
** T1b - Tumor more than 0.5cm but not more than 1.0cm in its greatest dimension.
:*Invasive ductal [[carcinoma]] not otherwise specified (NOS): ~65%
** T1c - Tumor more than 1.0cm but not more than 2.0cm in its greatest dimension.
:*Tubular[[carcinoma]] of breast: ~7-8%
*T2 - Tumor more than 2.0cm but not more than 5.0cm in its greatest dimension.
::*Tubulolobular [[carcinoma]]<nowiki/>of breast
*T3 - Tumor more than 5cm in its greatest dimension.
:*Medullary[[carcinoma]] of breast: ~2%
*T4 - Tumor of any size with direct extension to (a) chest wall or (b) skin as described below:
:*Mucinous (colloid) carcinoma: ~2%
** T4a - Extension to chest wall.
:*Malignant papillary lesions of the breast
** T4b - [[Edema]] (including [[peau d'orange]]) or ulceration of the breast skin, or satellite skin nodules confined to the same breast.
::*Papillary carcinoma of breast: 1-2% 1
** T4c - Both T4a and T4b.
|-
** T4d - [[Inflammatory breast cancer]].
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
'''Lobular'''
| style="padding: 5px 5px; background: #F5F5F5;" |
*[[Lobular carcinoma in situ]] (LCIS)
*[[Invasive lobular carcinoma]]: ~10%
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
'''Other malignant breast tumors'''
| style="padding: 5px 5px; background: #F5F5F5;" |
*[[Inflammatory breast cancer]]: 1-4%
*[[Paget's disease of the breast]]
*Triple negative and basal-like breast cancers
*Metaplastic carcinoma of the breast
*Adenoid cystic carcinoma of the breast: <0.4%
*Apocrine carcinoma of the breast
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
'''Sarcoma'''
| style="padding: 5px 5px; background: #F5F5F5;" |
*[[Angiosarcoma of the breast]]
*[[Fibrosarcoma]] of breast
*Extra-skeletal osteosarcoma of breast
*Malignant [[phyllodes tumor]]
*[[Angiosarcoma]]
*[[Rhabdomyosarcoma]]
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
'''Lymphoma'''
| style="padding: 5px 5px; background: #F5F5F5;" |
*[[Non-hodgkin lymphoma]]
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
'''Metastases to the breast'''
| style="padding: 5px 5px; background: #F5F5F5;" |
The most common extra-mammary cancers that metastasise to breast are:
*[[Lymphoma]]/[[leukaemia]]: most common extra mammary source
*[[Melanoma]]
*[[Sarcomas]]
*[[Prostate cancer]]: considered on the most frequent primary sites in men 4
*[[Lung cancer]]
*[[Gastric cancer]]
*[[Ovarian cancer]]
*[[Renal cell cancer]]
|-
|}


[[lymph node|Lymph '''N'''ode]] - There are four lymph node classification values (N0, N1, N2 or N3) which depend on the number, size and location of breast cancer cell deposits in lymph nodes.
===Benign Tumors===
* Nx - regional lymph nodes cannot be assessed. Perhaps due to previous removal.
*[[Phyllodes tumor]]<ref name="class">Breast Neoplasms. Radiopaedia (2015) http://radiopaedia.org/articles/breast-neoplasms Accessed on january 16, 2016 </ref>
* N0 - no regional lymph node metastasis.
*Mammary fibromatosis: 0.2% of all breast tumors 5
* N1 - metastasis to movable regional axillary lymph nodes on the same side as the affected breast.
*Benign papillary lesions of the breast
* N2 - metastasis to fixed regional axillary lymph nodes, or metastasis to the internal mammary lymph nodes, on the same side as the affected breast.
:*[[Papilloma]]
* N3 - metastasis to supraclavicular lymph nodes or infraclavicular lymph nodes or metastasis to the internal mammary lymph nodes with metastasis to the axillary lymph nodes.
::*[[Intraductal papilloma]]
::*Solitary papilloma of breast
::*Central solitary papilloma of breast
::*Peripheral solitary papilloma of breast
::*Multiple papillomata of breast
:::*Juvenile papillomatosis of breast
*Granular cell tumor of the breast


[[Metastasis|'''M'''etastases]] - There are two metastatic classification values (M0 or M1) which depend on the presence or absence of breast cancer cells in locations other than the breast and lymph nodes (so-called distant metastases, e.g. to bone, brain, lung).
==Classification based on hormone receptors present==
*'''Hormone receptor positive''': either estrogen or progesterone receptors are present
*'''Hormone receptor negative''': breast cancer cells do not have either estrogen or progesterone receptors
*'''[[HER2]] positive''': If excess copies of [[HER2|HER2 gene]]
*'''[[HER2]] negative''': If excess copies of [[HER2|HER2 gene]] are not present
*'''Triple positive''': cancers that are [[Estrogen receptor|ER]]-positive, PR-positive, and have too much HER2
*'''Triple negative''': If the breast cancer cells don not have estrogen or progesterone receptors and don’t have too much HER2


==Pathologic Types==
==Classification based on gene expression==
''''Note: The following list includes benign tumors (non cancers) as well as malignant tumors (cancers)''''
*'''Luminal type''': are estrogen receptor (ER)–positive
The latest (2003) [[World Health Organization]] (WHO)  classification of tumors of the breast<ref>''Tumours of the breast and female genital organs'', WHO classification of tumours, 2003, ISBN 9283224124</ref> recommends the following pathological types:
===Invasive Breast Carcinomas===
* [[Ductal carcinoma|Invasive ductal carcinoma]]
** Most are "not otherwise specified"
** The remainder are given subtypes:
*** Mixed type carcinoma
*** Pleomorphic carcinoma
*** Carcinoma with osteoclastic giant cells
*** Carcinoma with choriocarcinomatous features
*** Carcinoma with melanotic features
* Invasive lobular carcinoma
* Tubular carcinoma
* Invasive cribriform carcinoma
* [[Medullary carcinoma]]
* Mucinous carcinoma and other tumours with abundant mucin
** Mucinous carcinoma
** Cystadenocarcinoma and columnar cell mucinous carcinoma
** [[Signet ring cell carcinoma]]
* [[Neuroendocrine]] tumours
** Solid neuroendocrine carcinoma ([[carcinoid]] of the breast)
** Atypical carcinoid tumour
** Small cell / [[oat cell carcinoma]]
** Large cell neuroendocrine carcioma
* Invasive papillary carcinoma
* Invasive micropapillary carcinoma
* Apocrine carcinoma
* Metaplastic carcinomas
** Pure epithelial metaplastic carciomas
*** [[Squamous cell carcinoma]]
*** Adenocarcinoma with spindle cell metaplasia
*** Adenosquamous carcinoma
*** [[Mucoepidermoid carcinoma]]
** Mixed epithelial/mesenchymal metaplastic carcinomas
* Lipid-rich carcinoma
* Secretory carcinoma
* Oncocytic carcinoma
* Adenoid cystic carcinoma
* Acinic cell carcinoma
* Glycogen-rich clear cell carcinoma
* Sebaceous carcinoma
* [[Inflammatory breast cancer|Inflammatory carcinoma]]
* Bilateral breast carcinoma
 
===Mesenchymal Tumors (Including [[Sarcoma]])===
* Haemangioma
* Angiomatosis
* Haemangiopericytoma
* Pseudoangiomatous stromal hyperplasia
* Myofibroblastoma
* Fibromatosis (aggressive)
* Inflammatory myofibroblastic tumour
* [[Lipoma]]
** Angiolipoma
* Granular cell tumour
* [[Neurofibroma]]
* [[Schwannoma]]
* Angiosarcoma
* Liposarcoma
* Rhabdomyosarcoma
* Osteosarcoma
* [[Leiomyoma]]
* Leiomysarcoma
 
===Precursor Lesions===
* Lobular neoplasia
** lobular carcinoma in situ
* Intraductal proliferative lesions
** Usual ductal [[hyperplasia]]
** Flat epithelial hyperplasia
** Atypical ductal hyperplasia
** [[Ductal carcinoma in situ]]
* Microinvasive carcinoma
* Intraductal papillary neoplasms
** Central [[papilloma]]
** Peripheral papilloma
** Atypical papilloma
** Intraductal papillary carcinoma
** Intracystic papillary carcinoma
 
===Benign Epithelial Lesions===
* Adenosis, including variants
** Sclerosing adenosis
** Apocrine adenosis
** Blunt duct adenosis
** Microglandular adenosis
** Adenomyoepithelial adenosis
* Radial scar / complex sclerosing lesion
* Adenomas
** Tubular adenoma
** Lactating adenoma
** Apocrine adenoma
** [[Pleomorphic adenoma]]
** Ductal adenoma
 
===Myoepithelial Lesions===
* Myoepitheliosis
* Adenomyoepithelial adenosis
* Adenomyoepithelioma
* Malignant myoepithelioma
 
===Fibroepithelial Tumors===
* [[Fibroadenoma]]
* [[Phyllodes tumour]]
** Benign
** Borderline
** Malignant
* Periductal stromal sarcoma, low grade
* Mammary [[hamartoma]]
 
===Tumours of the Nipple===
* Nipple adenoma
* Syringomatous adenoma
* [[Paget's disease]] of the nipple
 
===Malignant [[Lymphoma]]===
 
===Metastatic Tumors===
 
===Tumors of the Male Breast===
* [[Gynecomastia]]
* Carcinoma
** In situ
** Invasive
 
==Histologic Types==
The classifications above show that breast cancer is usually, but not always, classified by its histological appearance. Rare variants are defined on the basis of [[physical exam]] findings. For example, [[Inflammatory breast cancer]] (IBC), a form of ductal carcinoma or malignant cancer in the ducts, is distinguished from other [[carcinoma]]s by the [[inflammation|inflamed]] appearance of the affected breast.<ref>{{cite journal |author=Giordano SH, Hortobagyi GN |title=Inflammatory breast cancer: clinical progress and the main problems that must be addressed |journal=Breast Cancer Res. |volume=5 |issue=6 |pages=284-8 |year=2003 |pmid=14580242 |doi=10.1186/bcr608}} [http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=14580242 Free Full Text].</ref> In the future, some pathologic classifications may be changed. For example, a subset of ductal carcinomas may be re-named [[basal-like carcinoma]] (part of the [[Triple Negative Breast Cancer|"triple-negative" tumors]]).
 
===Carcinomas===
====In situ====
*[[Ductal carcinoma]] (DCIS) 80%
*Lobular carcinoma (LCIS) 20%
 
====Invasive====
*Carcinoma NOS (not otherwise specified)
*Lobular carcinoma
*Tubular/cribriform carcinoma
*Mucinous (colloid) carcinoma
*Medullary carcinoma
*Papillary carcinoma
*Metaplastic carcinoma
 
====Sarcomas====
*[[Phyllodes tumour]]
 
==Gallery==
<gallery>
Image:Muc1.jpg|Infiltrating ductal carcinoma of the Breast assayed with anti Mucin 1 antibody
Image:HER2(2).jpg|Breast cancer (Infiltrating ductal carcinoma of the breast) assayed with anti HER-2 (ErbB2) antibody
Image:Breast invasive lobular carcinoma (2).jpg|Invasive lobular carcinoma of the breast  demonstrating a predominantly lobular growth pattern
Image:Tripolar Mitosis - breast carcinoma.jpg|Metaplastic (sarcomatoid) carcinoma of the breast.
Image:Breast DCIS histopathology (1).jpg|Histopathologic image from ductal cell carcinoma in situ (DCIS) of breast. Hematoxylin-eosin stain.
Image:Breast invasive scirrhous carcinoma histopathology (1).jpg|Histopathology of invasive ductal carcinoma of the breast representing a scirrhous growth. Core needle biopsy. Hematoxylin and eosin stain.
Image:Breast invasive scirrhous carcinoma histopathology (2) HER2 expression.JPG|Histopathology of invasive ductal carcinoma of the breast representing a scirrhous growth. Core needle biopsy. HER-2/neu oncoprotein expression by Ventana immunostaining system.
Image:IDC1.jpg|Breast cancer (Infiltrating ductal carcinoma of the breast) dyed with H&E
Image:Intraductal papilloma histopathology (1).jpg|Histopathology of intraductal papilloma of the breast by excisional biopsy. Hematoxylin and eosin stain.
Image:Intraductal papilloma histopathology (2) smooth muscle actin.JPG|Histopathology of intraductal papilloma of the breast by excisional biopsy. Immunostaining for alpha-smooth muscle actin.
Image:Intraductal papilloma histopathology (3) p63.JPG|Histopathology of intraductal papilloma of the breast by excisional biopsy. Immunostaining for p63 protein.
Image:Breast fibroadenoma by fine needle aspiration (1) DG stain.jpg|Breast fibroadenoma
Image:Breast fibroadenoma by fine needle aspiration (2) PAP stain.jpg|Breast fibroadenoma
Image:Breast fibradenoma (1).jpg|Histopathologic image of breast fibroadenoma. Core needle biopsy. Hematoxylin & eosin stain.
Image:Breast fibradenoma (2).jpg|Histopathologic image of breast fibroadenoma. Core needle biopsy. Hematoxylin & eosin stain.
</gallery>


:*'''Luminal A''':
::*Expression of luminal (low molecular weight) [[Cytokeratin|cytokeratins]], high expression of [[hormone receptor]]<nowiki/>s and related [[Gene|genes]]
::*50% of invasive bresat cancer, [[Estrogen receptor|ER]]/[[Progesterone receptor|PR]] positive, [[HER2/neu]] negative
::*Tubular carcinoma, Cribriform [[carcinoma]], Low grade invasive ductal [[carcinoma]], NOS, Classic lobular[[carcinoma]]
::*Response to endocrine therapy
::*Variable response to chemotherapy
::*Low grade,
::*Grows slowly,
::*Good prognosis (the best prognosis)
:*'''Luminal B :'''
::*Expression of luminal (low molecular weight) cytokeratins, moderate-low expression of hormone receptors and related genes
::*20% of invasive breast cancer, ER/PR positive, [[HER2/neu]] expression variable, higher proliferation than Luminal A, higher histologic grade than Luminal A
::*Invasive ductal [[carcinoma]], NOS Micropapillary [[carcinoma]]
::*Response to endocrine therapy (tamoxifene and aromatase inhibitors) not as good as Luminal A
::*Variable response to chemotherapy (better than Luminal A)
::*Prognosis not as good as Luminal A
::*Grows faster
:*'''HER2/neu'''
::*High expression of [[HER2/neu]], low expression of ER and related genes
::*15% of invasive breast cancer, ER/PR negative, [[HER2/neu]] positive, high proliferation, diffuse [[TP53]] mutation, high histologic grade and nodal positivity
::*High grade invasive ductal carcinoma, NOS
::*Response to [[trastuzumab]] [[Trastuzumab|(Herceptin]])
::*Response to chemotherapy with antracyclins
::*Usually unfavorable prognosis
:*'''Basal like'''
::*High expression of basal epithelial genes and basal cytokeratins, low expression of ER and related genes, low expression of HER2/neu
::*~15% of invasive breast cancer, most [[Estrogen receptor|ER]]/[[Progesterone receptor|PR]], [[HER2/neu]] negative (triple negative), high proliferation, diffuse [[TP53]] mutation, BRCA1 dysfunction (germline, sporadi
::*High grade invasive ductal [[carcinoma]], NOS Metaplastic [[carcinoma]], Medullary carcinoma
::*No response to endocrine therapy or trastuzumab
::*Sensitive to platinum group chemotherapy and PARP inhibitors
::*Not all, but usually worse prognosis<ref name="pmid28331693">Eliyatkın N, Yalçın E, Zengel B, Aktaş S, Vardar E (2015) [https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=28331693 Molecular Classification of Breast Carcinoma: From Traditional, Old-Fashioned Way to A New Age, and A New Way.] ''J Breast Health'' 11 (2):59-66. [http://dx.doi.org/10.5152/tjbh.2015.1669 DOI:10.5152/tjbh.2015.1669] PMID: [https://pubmed.gov/28331693 28331693]</ref>
==References==
==References==
{{reflist|2}}
{{reflist|2}}
 
[[Category:Disease]]
[[Category:Breast cancer]]
[[Category:Types of cancer]]
[[Category:Breast]]
[[Category:Hereditary cancers]]
[[Category:Mature chapter]]
[[Category:Oncology]]
[[Category:Oncology]]
{{WikiDoc Help Menu}}
{{WikiDoc Help Menu}}
{{WikiDoc Sources}}
{{WikiDoc Sources}}
[[Category:Up-To-Date]]
[[Category:Oncology]]
[[Category:Medicine]]
[[Category:Gynecology]]
[[Category:Surgery]]

Latest revision as of 20:00, 12 December 2019

Breast Cancer Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Breast cancer from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic study of choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

X-ray

CT scan

MRI

Echocardiography or Ultrasound

Other Imaging Studies

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Breast cancer classification On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Breast cancer classification

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Breast cancer classification

CDC on Breast cancer classification

Breast cancer classification in the news

Blogs on Breast cancer classification

Directions to Hospitals Treating Breast cancer

Risk calculators and risk factors for Breast cancer classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Mirdula Sharma, MBBS [2] Soroush Seifirad, M.D.[3]

Overview

Breast cancer may be classified according to anatomy into 4 subtypes: ductal, lobular, sarcoma, and lymphoma. There are also other methods of classification such as classification based on gene expression, and classification based on hormone receptors present. In practice, a combination of all above mentioned classification is combined with the surgical characteristics of tumors and radiologic findings is being applied for patient management, treatment planning, and prognosis determination.

Classification based on histopathology

Malignant Tumors
Type Subtype

Ductal

  • Comedo type: ~60%
  • Non-comedo type: ~40%
  • Papillary
  • Micropapillary
  • Cribriform
  • Solid
  • Invasive ductal carcinoma not otherwise specified (NOS): ~65%
  • Tubularcarcinoma of breast: ~7-8%
  • Medullarycarcinoma of breast: ~2%
  • Mucinous (colloid) carcinoma: ~2%
  • Malignant papillary lesions of the breast
  • Papillary carcinoma of breast: 1-2% 1

Lobular

Other malignant breast tumors

Sarcoma

Lymphoma

Metastases to the breast

The most common extra-mammary cancers that metastasise to breast are:

Benign Tumors

  • Phyllodes tumor[1]
  • Mammary fibromatosis: 0.2% of all breast tumors 5
  • Benign papillary lesions of the breast
  • Intraductal papilloma
  • Solitary papilloma of breast
  • Central solitary papilloma of breast
  • Peripheral solitary papilloma of breast
  • Multiple papillomata of breast
  • Juvenile papillomatosis of breast
  • Granular cell tumor of the breast

Classification based on hormone receptors present

  • Hormone receptor positive: either estrogen or progesterone receptors are present
  • Hormone receptor negative: breast cancer cells do not have either estrogen or progesterone receptors
  • HER2 positive: If excess copies of HER2 gene
  • HER2 negative: If excess copies of HER2 gene are not present
  • Triple positive: cancers that are ER-positive, PR-positive, and have too much HER2
  • Triple negative: If the breast cancer cells don not have estrogen or progesterone receptors and don’t have too much HER2

Classification based on gene expression

  • Luminal type: are estrogen receptor (ER)–positive
  • Luminal A:
  • Expression of luminal (low molecular weight) cytokeratins, high expression of hormone receptors and related genes
  • 50% of invasive bresat cancer, ER/PR positive, HER2/neu negative
  • Tubular carcinoma, Cribriform carcinoma, Low grade invasive ductal carcinoma, NOS, Classic lobularcarcinoma
  • Response to endocrine therapy
  • Variable response to chemotherapy
  • Low grade,
  • Grows slowly,
  • Good prognosis (the best prognosis)
  • Luminal B :
  • Expression of luminal (low molecular weight) cytokeratins, moderate-low expression of hormone receptors and related genes
  • 20% of invasive breast cancer, ER/PR positive, HER2/neu expression variable, higher proliferation than Luminal A, higher histologic grade than Luminal A
  • Invasive ductal carcinoma, NOS Micropapillary carcinoma
  • Response to endocrine therapy (tamoxifene and aromatase inhibitors) not as good as Luminal A
  • Variable response to chemotherapy (better than Luminal A)
  • Prognosis not as good as Luminal A
  • Grows faster
  • HER2/neu
  • High expression of HER2/neu, low expression of ER and related genes
  • 15% of invasive breast cancer, ER/PR negative, HER2/neu positive, high proliferation, diffuse TP53 mutation, high histologic grade and nodal positivity
  • High grade invasive ductal carcinoma, NOS
  • Response to trastuzumab (Herceptin)
  • Response to chemotherapy with antracyclins
  • Usually unfavorable prognosis
  • Basal like
  • High expression of basal epithelial genes and basal cytokeratins, low expression of ER and related genes, low expression of HER2/neu
  • ~15% of invasive breast cancer, most ER/PR, HER2/neu negative (triple negative), high proliferation, diffuse TP53 mutation, BRCA1 dysfunction (germline, sporadi
  • High grade invasive ductal carcinoma, NOS Metaplastic carcinoma, Medullary carcinoma
  • No response to endocrine therapy or trastuzumab
  • Sensitive to platinum group chemotherapy and PARP inhibitors
  • Not all, but usually worse prognosis[2]

References

  1. ↑ 1.0 1.1 Breast Neoplasm. Radiopedia. (2015) http://radiopaedia.org/articles/breast-neoplasms Accessed on March 1, 2019
  2. ↑ Eliyatkın N, Yalçın E, Zengel B, Aktaş S, Vardar E (2015) Molecular Classification of Breast Carcinoma: From Traditional, Old-Fashioned Way to A New Age, and A New Way. J Breast Health 11 (2):59-66. DOI:10.5152/tjbh.2015.1669 PMID: 28331693

Template:WikiDoc Sources

Retrieved from "https://www.wikidoc.org/index.php?title=Breast_cancer_classification&oldid=1591486"