A 60-year-old woman with hypertension, dyslipidemia, and 35–pack-year smoking history is referred for treatment of advanced non–small-cell lung cancer (NSCLC). She initially presented after a transient ischemic attack, when a chest radiograph demonstrated a right lung mass. Computed tomography (CT) of the chest revealed a 5-cm right upper lobe mass, without mediastinal adenopathy, and a 6-cm cystic mass in the spleen. Additional imaging showed no brain metastasis. Endobronchial ulstrasound-guided core biopsies of the lung mass and ipsilateral mediastinal nodes confirmed a poorly differentiated non–small-cell carcinoma. Immunohistochemical stains were positive for napsin A and thyroid transcription factor 1, suggestive of adenocarcinoma ( Fig 1 ). Molecular analysis identified a KRAS G12C mutation. A positron emission tomography (PET) –CT scan demonstrated [18F]fluorodeoxyglucose uptake in the right upper lobe mass and splenic lesion ( Fig 2 A). CT-guided fine-needle aspiration of the splenic lesion was performed and revealed metastatic carcinoma, consistent with the lung primary. Treatment with carboplatin plus pemetrexed was initiated, without bevacizumab because of the recent transient ischemic attack; carboplatin was selected over cisplatin because of similar concerns. The patient received two cycles of chemotherapy without complications, and repeat imaging showed decrease in size of the lung mass and splenic lesion ( Figs 2 B and 2 C). After four cycles of chemotherapy, a chest CT showed ongoing response ( Fig 2 D). Her Eastern Cooperative Oncology Group performance status remained 0.
P1‐93: A case of lung mass with bifurcation that was difficult to differentiate from lung cancer
