Suspicious for malignancy, The International Academy of Cytology Yokohama System for Reporting Breast Fine-Needle Aspiration cytology
Recommendation for core biopsy
- Mixture of large and small tight epithelial tissue fragments with crowding of cells
- large three dimensional tissue fragments
- Some areas shows a cribriform architecture with sharp punched out holes and nuclear orientation towards lumen
- Few dispersed cells shows low- to intermediate-grade nuclear atypia
- Most of the areas show cohesive pattern
- Areas of adipose tissue entanglement is seen with moderate atypia
- Mitotic activity is not apparent.
- Necrosis is not seen
- Papillary fragments are not seen
- Myoepithelial cells are bare bipolar nuclei are not seen.
Practical points of Pathoclinics:
- Low to intermediate grade atypia with striking cribriform pattern and crowded clusters in infiltrative pattern in an adipose tissue favours Invasive low-grade cribriform ductal carcinoma or low-grade cribriform ductal carcinoma in situ (DCIS) over the ductal epithelial hyperplasia with cribriform pattern.
- Due to absence of myoepithelial cells, presence of moderate nuclear atypia and overlapping and crowded three dimensional tissue fragments in an adipose tissue are against to call this as only “Atypia” in IAC Yokohama system.
- In dilemma cases, it is wise use Suspicious category, with recommendation of core needle biopsy, to avoid potential overcall of malignant.
- Adenoid cystic carcinoma is also differentials here. It shows small dark hyperchromatic cells cylindrical/cribriform structures with hyaline globules. Moderate cellular atypia and absence of any hyaline type material rules out possibility adenoid cystic carcinoma. ER and PR comes negative in adenoid cystic carcinoma of breast in contrast to low-grade cribriform ductal carcinoma in situ
- Epithelial hyperplasia can show slit like lumen in tissue fragments along with mild atypia. But presence of myoepithelial cells and bare nuclei are reliable indicator to consider this as a Benign or atypical category of IAC Yokohama.
- Follow up Histopathology shows Invasive low-grade cribriform ductal carcinoma