Breast Pathology 2 Flashcards
(40 cards)
4 non-carcinomatous breast cancers?
malignant phyllodes tumour (sarcomatous stromal component)
angiosarcoma
lymphoma
metastatic
which cancers often metastasise to the breast?
carcinoma of bronchus, ovary and kidney
malignant melanoma
soft tissue tumours (leiomyosarcoma)
definition of carcinoma?
malignant tumour of epithelial cells
where does breast carcinoma arise?
glandular epithelium of the terminal duct lobular unit (TDLU)
breast carcinomas are actually what type?
adenocarcinoma
- but just called breast carcinoma
ductal precursor lesions?
epithelial hyperplasia of usual type
columnar cell change (+/- atypia)
atypical ductal hyperplasia
ductal carcinoma in situ
lobular precursor lesions?
lobular in situ neoplasia
- atypical lobular hyperplasia
- lobular carcinoma in situ
what is an in situ carcinoma?
confined within basement membrane of acini and ducts
cytologically malignant but non-invasive
non-obligate precursor of invasive carcinoma
classification of breast carcinoma in situ?
lobular
ductal
2 historic entities of lobular in situ carcinoma?
atypical lobular hyperplasia (ALH)
- <50% of lobule involved
lobular carcinoma in situ (LCIS)
- >50% of lobule involved
histology of lobular in situ neoplasia?
intra-lobular proliferation of characteristic cells
- small nuclei
- solid proliferation
- intra cytoplasmic lumens/vacuoles
- ER positive
- E cadherin negative
features of lobular in situ neoplasia?
often multifocal and bilateral less common after the menopause not palpable, not visible grossly may calcify (mammography) usually an incidental finding
significance of lobular in situ neoplasia?
gives 8X higher risk of invasive carcinoma
LCIS = highest risk
how is lobular in situ neoplasia managed?
if found on core biopsy = excision or vacuum biopsy to exclude higher grade lesion
if found on vacuum or excision biopsy = follow up and clinical trials
types of intraductal proliferation?
epithelial hyperplasia of usual type columnar cell change (lesion) columnar cell change with atypia atypical ductal hyperplasia ductal carcinoma in situ
how does intraductal proliferation affect risk of progression to invasive carcinoma?
epithelial hyperplasia of usual type = 2X risk
atypical ductal hyperplasia = 4X risk
DCIS = 10X risk
features of ductal carcinoma in situ?
arises in TDLU
characteristically unicentric (single duct system)
may involve lobules (cancerisation)
may involve nipple skin (pagets)
cytologically malignant epithelial cells confined to basement membrane
what is pagets disease of the nipple?
high grade DCIS extending along ducts to reach the epidermis of the nipple
still in situ carcinoma (non-invasive)
causes indendation etc of skin around nipple
classification of DCIS?
which is most significant in terms of progression to invasive carcinoma?
cytological grade (most significant) histological type presence of necrosis (comedo)
significance of DCIS in terms of progression?
risk factor for development of invasive carcinoma
true precursor for invasive carcinoma
how is DCIS managed?
diagnosis
surgery
adjuvant radiotherapy
chemoprevention (endocrine therapy)
what is a microinvasive carcinoma?
DCIS which has invaded the basement membrane but <1mm
rare
treated as high grade DCIS
what is invasive breast carcinoma?
malignant epithelial cells have breaches the basement membrane
infiltration of normal tissues
peak incidence for breast cancer?
50-70 (when breast screening is offered)
