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3. Percutaneous transthoracic fine needle aspiration and core biopsy
While the other tissue sampling procedures listed- bronchoscopy with transbronchial biopsy and surgical lung biopsy- may be capable of establishing a diagnosis, percutaneous transthoracic fine needle aspiration and core biopsy may be the best choice among those listed because it is the least invasive method for obtaining a fairly large tissue sample. Bronchoscopy with transbronchial biopsy is less invasive than percutaneous transthoracic fine needle aspiration and core biopsy, but the tissue sample is smaller with the former compared with the latter, and the addition of core biopsy in this circumstance is important, as the diagnosis may not be a cytologically-evident carcinoma, in which case the histopathological sample provided by core biopsy may prove definitive. Surgical lung biopsy certainly is capable of obtaining the tissue needed for diagnosis, but is more invasive compared with percutaneous transthoracic fine needle aspiration and core biopsy and is potentially not needed to establish a definitive diagnosis.18FDG-PET scanning may prove useful for evaluation of the nodules in this patient, but the lack of tracer utilization within the nodules would not preclude the need to establish a definitive diagnosis, and elevated tracer utilization within the nodules would add no new management-altering information. It could be reasoned that, if some of the nodules showed tracer accumulation at 18FFDG-PET and others did not, tissue sampling should be directed towards the metabolically active lesions, but this approach still leaves tissue sampling as the primary consideration for the next step in management.
Percutaneous fine needle aspiration biopsy and core biopsy of the dominant right middle lobe nodule was performed (Figure 5).
Figure 5. Axial unenhanced thoracic CT shows percutaneous placement of the biopsy needle in the dominant right middle lobe nodule.
The biopsy showed fragments of pulmonary parenchyma entrapped within foci of proliferating fusiform cells containing eosinophilic cytoplasm and oval nuclei. A proliferation of cytologically benign-appearing smooth muscle cells without anaplasia was noted, and necrosis, mitotic activity, and pleomorphism were not seen. Immunohistochemical staining showed strong, diffuse nuclear staining for estrogen and progesterone receptors and diffuse cytoplasmic staining for smooth muscle-specific actin, but without staining for CD10 (a B-lymphocyte marker), and only weak activity for vimentin.
In light of these histopathological findings, among the following choices, which piece of historical information is most useful for establishing the diagnosis for this patient? (click on the correct answer to be directed to the eleventh and last page)