A 63-year-old male with a recently diagnosed right lung lesion was referred for staging. F-FDG PET/CT scan revealed a hypodense, cystic-like mass in the right upper lung lobe, which demonstrated low, diffuse ¹⁸F-FDG uptake, likely due to the presence of mucus, as well as intensely hypermetabolic right hilar and right paratracheal lymph nodes. Transbronchial biopsy revealed a primary pulmonary mucinous cystadenocarcinoma with the presence of signet ring cell carcinoma, a co-existence of two rare variants of lung adenocarcinoma. This case report demonstrates the metabolic phenotype along with the radiographic characteristics of this rare tumor and its metastases.
Adenocarcinoma ; Biopsy ; Carcinoma, Signet Ring Cell ; Cystadenocarcinoma, Mucinous ; Fluorodeoxyglucose F18 ; Humans ; Lung ; Lung Neoplasms ; Lymph Nodes ; Male ; Middle Aged ; Mucins ; Mucus ; Neoplasm Metastasis ; Phenotype ; Positron-Emission Tomography ; Positron-Emission Tomography and Computed Tomography