Intermediate
Technical
IVT
anaplastic focus
Discrete area within a lower-grade tumor showing high-grade features such as increased mitoses or necrosis.
Full Definition
A localized region within an otherwise lower-grade brain tumor that demonstrates histological features of anaplasia, including increased mitotic activity, nuclear pleomorphism, increased cellularity, or necrosis. The presence of anaplastic foci can upgrade the entire tumor to a higher grade and significantly impacts prognosis and treatment decisions. These areas may be focal and require careful sampling and examination to detect, as they can be missed in small biopsies or inadequate tissue sampling.
Usage
Usage note: Document location and extent when describing anaplastic foci in diagnostic reports.
In Context
- "Multiple anaplastic foci were identified throughout the resection specimen, upgrading the tumor to grade III." — Surgical pathology report
- "The presence of even small anaplastic foci necessitates classification as anaplastic astrocytoma." — Diagnostic consultation
Also known as
high-grade focus
anaplastic area
Don't confuse with
reactive changes
processing artifact