MCQ Pathology Answer 50

Infiltrating Lobular Carcinoma (invasive breast carcinoma)

Presentation

• May or may not have mass
• No desmoplastic response so hard to see and feel – clinically and mammogram occult
  

Pathology:

• Gross: solid mass but maybe completely undetectable
• Histo: linear, single cells or targetoid pattern of malignant cells, low nuclear grade, minimum mitotic activity
• NO desmoplastic response
  

Infiltrating Lobular Carcinoma is the second most common form of invasive breast cancer. Because it does not create a reactive desmoplastic response in the tissue, it may be clinically and mammographically occult. It also tends to be larger than clinically estimated preoperatively.

1. It has an increased propensity to be multicenteric (involve more than one part of the breast) and to be bilateral (affect both breasts). It also has the propensity to metastasize to unusual sites, such as the gynecologic and GI tract.
   
2. It has the same prognosis (comparable survival) as infiltrating ductal carcinoma, when matched, stage for stage!
   
3. It is usually ER+/PR+ , CerbB-2/HER2 –
   
4. It usually has single cells invading the stroma, thus it is hard to see on low power. You can do a positive cytokertain stain to confirm the epithelial nature of the lobular carcinoma.

Category: Pathology MCQs