Thyroid Incidentaloma on 68Ga-PSMA-11 PET/CT Leading to Detection of Thyroid Metastasis in Metastatic Prostate Carcinoma.

68Ga-labeled prostate-specific membrane antigen (PSMA)-11 PET/CT has evolved as the noninvasive imaging modality of choice in prostatic adenocarcinoma to detect overexpression of PSMA on prostate cancer cells. Metastasis to the thyroid gland is rarely observed in clinical practice of prostatic adenocarcinoma. Herein, we report the first and rare case of metastatic castration-resistant prostatic adenocarcinoma with thyroid metastasis. The patient demonstrated intensely PSMA-expressing primary prostatic lesion, metastatic lymph nodes, and skeletal lesions, and also mild uptake in thyroid nodule, which on further investigations was established as thyroid metastasis from prostate adenocarcinoma.