RESUMO
Uveal melanoma (UV) is a rare and aggressive melanoma with poor 1-year survival. up to 50% of UV patients develop metastases, mainly to the liver. Here, the authors present a 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography (18F-FDG-PET) study of a very rare case of secondarily metastatic UV in an 81-year-old Caucasian with a dramatic response to pembrolizumab associated with serial pseudogression. 18F-FDG-PET associated with clinical status and peripheral blood derived neutrophil-to-lymphocyte ratio (dNLR) were performed to guide therapeutic strategy due to an atypical pseudoprogression phenomenon.
Assuntos
Melanoma , Humanos , Idoso de 80 Anos ou mais , Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Melanoma/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodosRESUMO
ABSTRACT: Schwannomas are usually benign, rare, and slow-growing nerve sheath tumor composed of Schwann cells. They develop in the head and neck area in approximately 25% to 40% of cases, of which 1% in the oral cavity, where the tongue remains the preferred site. Malignant transformation occurs in approximately 8% to 10% cases. We report a unique case of a histologically proven FDG-avid schwannoma of the left mobile portion of the tongue, showing an 18F-FDG avidity on PET/CT, which was a false-positive result for local recurrence in a patient followed for squamous cell carcinoma.
Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neurilemoma , Humanos , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Seguimentos , Achados Incidentais , Carcinoma de Células Escamosas/diagnóstico por imagem , Língua/patologia , Neurilemoma/diagnóstico por imagem , Neurilemoma/patologiaRESUMO
Epithelial-myoepithelial carcinoma (EMC) is a rare malignant neoplasm arising most frequently in the salivary glands and exceptionally in the nasal cavity. EMC accounts for ~1-2% of salivary gland tumors. Even if the nodal and distant metastasis rates are low, tumor staging remains indicated. Here, the authors present the 2-deoxy-2-[18F]fluoro-D-glucose PET-CT (18F-FDG-PET/CT) study of a very rare case of biopsy-proven EMC of the left nasal cavity. This 18F-FDG-PET/CT was performed to stage this tumor and guide the therapeutic strategy due to an atypical high-grade presentation in immunohistochemistry. To our knowledge, this is the first case reporting such high 18F-FDG avidity of EMC of the nasal cavity in PET/CT.