Background: PET/CT may be particularly useful to detect the primary cancer in paraneoplastic cerebellar degeneration (PCD) with anti-Yo which is most commonly associated with breast, ovarian and other gynecological cancers.
Case: A 60-year-old woman developed a PCD associated with anti-Yo antibodies in serum and cerebrospinal fluid. Conventional imaging was negative. FDG-PET showed an abnormal hot spot in the right ovarian area associated with lombo aortic lymph nodes. The diagnosis was confirmed by surgery as an ovarian adenocarcinoma.
Conclusion: In this case report, FDG-PET played a crucial role in detecting the unknown primary tumor in a patient with PCD.