Lobular carcinoma in situ
Lobular carcinoma in situ (LCIS) typically display monomorphic, loosely cohesive, slightly enlarged and evenly spaced cells that fill acini. Cells have indistinct cell borders, pale cytoplasm, and uniform small nuclei with evenly distributed chromatin and inconspicuous nucleoli.
The main differential diagnosis is ductal carcinoma in situ (DCIS).
In DCIS, the cells are cohesive and have high grade atypia.
LCIS typically fills smaller lobules rather than ducts, but DCIS can display lobular cancerization as shown at bottom of image.[image 1]
When unsure, perform immunohistochemistry for E-cadherin and p120:
In contrast, both E-cadherin (left image below) and p120 (right) have a membranous staining pattern in ductal carcinoma in situ (DCIS).
Generally perform immunohistochemistry for estrogen and progesterone receptors and calculate the percentage of positive tumor cells.
It should contain:
- Type of resection or biopsy, and location
- Results of any supplementary studies performed
However, grading and staging is not applicable. (Margins of excision are not relevant)
See also: General notes on reporting
- Sucheta Srivastava. Breast - Noninvasive lobular neoplasia - LCIS classic. Topic Completed: 1 September 2017. Minor changes: 21 June 2020
- Sucheta Srivastava, M.D.. Breast - Noninvasive lobular neoplasia - LCIS classic (Differential diagnosis section). Topic Completed: 1 September 2017. Minor changes: 17 May 2021
- . Lobular Carcinoma in Situ of the Breast. Surgical Pathology Criteria. Retrieved on 2021-12-14.