Correct!
6. More than one of the above
The nodule, now a mass (since it is larger than 3 cm), has clearly enlarged. The relatively prolonged volume of doubling time of 1325 days suggests a benign etiology. Nodule volume of doubling times ˃400 days are more commonly associated with benign diagnoses, it is recognized that some malignant lesions may grow slowly, including bronchogenic carcinomas along the adenocarcinoma spectrum and carcinoid tumors; even extraparenchymal malignancies, such as solitary fibrous tumor of the pleura, may grow slowly. Hence, any growth in a thoracic lesion must be regarded with some suspicion. In fact, in rare circumstances, a malignancy may arise within a benign lesion, either because of malignant degermation, or as a “collision” tumor (a separate malignant lesion within or adjacent to a benign lesion), and such lesions may be recognized through interval growth. Hence a tissue diagnosis is a reasonable choice of action, and any of the above choices could be employed for this purpose. 18FDG-PET probably would add little value in this circumstance because the results of 18FDG-PET would not change management- if the lesion shows tracer uptake, a tissue diagnosis is warranted, but if the lesion shows no tracer uptake, it has grown and hence a tissue diagnosis is probably still warranted. It is possible that 18FDG-PET could disclose another abnormality that could be more easily targeted, but the likelihood of such is quite low in this patient.
The patient then underwent flexible fiberoptic bronchoscopy with transbronchial fine needle aspiration and ultrasound-guided transbronchial cryobiopsy. Bronchoalveolar lavage was performed in the inferior lingular segment.
Based on the data thus far, which of the following represents the most likely diagnosis for this patient’s left lower lobe mass? (Click on the correct answer to be directed to the 15th of 17pages)