FIGURE 2. FDG-positive residual tumor and lymph node metastasis (arrows) in 57-y-old woman who presented after incomplete thyroidectomy and tumor resection of papillary thyroid cancer initially staged as pT4bN1Mx (A). FDG PET was performed to assess tumor extension and possible metastases before further surgery. Residual tumor masses were seen after additional surgery (B), and external irradiation yielded good response (C). After irradiation, hTg levels dropped from 24 to 1.5 µg/L. Images show maximum-intensity projections in anterior views.