Lack of FDG uptake in small cell carcinoma associated with ANNA-1 positive paraneoplastic autonomic neuropathy.
A 76-year-old smoker presented with profound weight loss due to gastrointestinal dysmotility associated with high levels of the paraneoplastic antibody ANNA-1. Serial computed tomography scans showed regressing subcarinal adenopathy, and positron emission tomography imaging showed mild fluorodeoxy-d-glucose uptake in subcarinal nodes, suggestive of benign disease. Diagnosis of small cell carcinoma was established by biopsy of mediastinal nodes. This case highlights the importance of a thorough search for malignancy in patients with high levels of circulating autoantibodies and suggests that benign-appearing imaging studies be interpreted with caution in patients with paraneoplastic autoimmune syndromes.
Block
Matthew S
MS
Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA.
Vassallo
Robert
R
D000368:Aged; D000912:Antibodies, Neoplasm / Q000032:analysis; D001706:Biopsy; D018288:Carcinoma, Small Cell / Q000150:complications* / Q000000981:diagnostic imaging* / Q000628:therapy; D003937:Diagnosis, Differential; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications* / Q000000981:diagnostic imaging* / Q000628:therapy; D008297:Male; D020364:Paraneoplastic Polyneuropathy / Q000150:complications* / Q000628:therapy; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D014057:Tomography, X-Ray Computed
D000912:Antibodies, Neoplasm; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18