23
Pathologic Assessment
ATC?
Undifferentiated Neoplasm
NOT ATC
Y
Y
N
N
Histology & IHC,
assess as indicated,
including:
• TTF-1, Tg, PAX8
• BRAF
V600E
#
Differential Diagnosis:
• Lymphoma
• Metastasis
• Sarcoma
• Squamous call carcinoma
lung/head and neck
• Other
+
Assess with US to consider/exclude benign conditions (e.g., hemorrhage into cyst).
# Tumor IHC for BRAF
V600E
or circulating/free DNA assessment are considered sufficiently robust for
guiding initial clinical care but require confirmation by tumor DNA sequencing.
