Demonstration of focal physiologic in-vivo somatostatin receptor expression in the caput epididymis of the testes on 68Ga-DOTANOC PET/CT and 177Lu-DOTATATE post-therapy whole body scintigraphy

We present the case of a 60-year-old man with metastatic neuroendocrine tumor of the ileum following ileal resection, being evaluated for 177Lu-based peptide receptor radionuclide therapy. 68Ga-DOTANOC PET/CT showed focal increased tracer uptake in the scrotal region without any morphologic changes on the corresponding CT images. Similar increased tracer uptake was seen on post-therapy whole-body imaging following 177Lu-DOTATATE therapy. An USG guided FNA revealed no malignant cells on cytopathologic examination. This case illustrates that focal testicular tracer uptake, may not always be pathological and can represent a normal physiologic variant, similar to the diffuse testicular somatostatin receptor expression as previously reported in literature.

Demonstration of focal physiologic in-vivo somatostatin receptor expression in the caput epididymis of the testes on 68Ga-DOTANOC PET/CT and 177Lu-DOTATATE post-therapy whole body scintigraphy Keywords:

68Ga-DOTANOC- PET/CT , Testicular uptake , Physiologic Neuroendocrine tumor , 177Lu-DOTATATE , Somatostatin receptor , DOTATOC