Malignancy of the secretory lobules of the breast that is contained within the basement membrane
Aetiology
Usually diagnosed before menopause
Pathophysiology
Much rarer than DCIS however individuals with LCIS are at greater risk of developing an invasive breast malignancy
Clinical presentation
Usually asymptomatic
Investigations
LCIS is usually asymptomatic, much like DCIS, however LCIS is not associated with microcalcifications but instead usually diagnosed as an incidental finding during biopsy of the breast
Management
If L(is)N discovered on core biopsy - proceed to excision or vacuum biopsy to exclude higher grade lesion
If L(is)N is discovered on vacuum or excision biopsy - followup, clinical trials
Other lobular precursor lesions
Lobular carcinoma in situ involves >50% of lobule involved; atypical lobular hyperplasia is the term used when <50% of lobule involved