FIG. 2.

A patient from the current lethal cohort with a 0.4 cm papillary microcarcinoma of the thyroid and concurrent metastatic PDTC in a 3.2 cm ipsilateral neck level III lymph node. (A) The primary thyroid microcarcinoma was a partially encapsulated papillary microcarcinoma composed exclusively of follicles. Nuclear features of papillary carcinoma, such as nuclear membrane irregularity, chromatin clearing, and nuclear grooves, were readily identified (B). (C) and (D) The metastatic MSKCC-PDTC in the lymph node exhibited follicular growth pattern and tumor necrosis (N) while retaining the nuclear features of PTC (D).