Figure 1: Preoperative PET/CT findings from a 67 year old man with a left buttock primary Merkel cell carcinoma. This study confirmed the presence of palpable left inguinal lymph node metastases (horizontal white arrow) in addition to left obturator lymph node avidity, but also demonstrated avid right inguinal lymphadenopathy (vertical white arrow) that was not clinically palpable. Biopsy of the right inguinal lymph node confirmed the presence of metastatic Merkel cell carcinoma which led to a formal right inguinal lymphadenectomy.