Pathological findings of pulmonary papillary adenoma with EGFR mutation and literature review: two cases report.

OBJECTIVE: Pulmonary papillary adenoma is an extremely rare benign tumor. It is derived from type II lung cells and club cells, suggesting that it may originate from stem cells with two-way differentiation. Only one case has been reported with FGFR2-IIIb overexpression. METHODS: Two cases of pulmonary papillary adenoma with available data on clinical features, histological morphology, immunophenotype and molecular characteristics were analyzed. RESULTS: Both tumors were well-circumscribed unencapsulated nodules composed of papillary structures with fibrovascular cores lined by a single layer of cuboidal or columnar epithelium without necrosis, nuclear atypia and mitoses, or invasion. But malignant transformation features include complex branching structures and significantly enlarged, irregular, and crowded malignant cells in one case. Immunohistochemistry showed that the tumor cells were strongly positive for TTF1, NapsinA, EMA and CK7 and negative for CEA and P63, with a low Ki-67 proliferation index. The EGFR somatic mutation exon19:c.2236_2256delinsATC (p.E746_S752delinsI) was found in one case by next-generation sequencing (NGS) technology. CONCLUSION: Pulmonary papillary adenoma is very rare. Virtually all papillary adenomas are clinically silent and discovered incidentally. They are benign tumors, and resection is curative. An EGFR 19 exon deletion mutation in a patient with this tumor type was detected for the first time by NGS, and our results suggest that the malignant transformation of pulmonary papillary adenoma may be mediated by EGFR mutation.

Diagnostic Value of X-Map Images Reconstructed by Plain Dual-Energy Computed Tomography Scans in Acute Ischemic Stroke.

OBJECTIVE: This study aimed to evaluate the diagnostic value of X-Map reconstruction based on Dual-Energy Computed Tomography (DECT) in acute ischemic stroke (AIS). METHODS: Sixty-six cases of suspected AIS patients hospitalized from November, 2021 to April, 2022 were retrospectively selected. DECT, Computed Tomography Perfusion imaging (CTP), Computed Tomography Angiography (CTA), and MRI were all performed within 24 hours after symptom onset. As the gold standard for diagnosing AIS, a total of 53 patients were diagnosed with AIS based on the diffusion-weighted imaging positive results in MRI. The Chi-square test was used to evaluate the diagnostic efficacy of AIS among X-Map, CTP, and CTA. RESULTS: In the 53 patients with confirmed ASI, a total of 72 lesions were detected, including in the frontal lobes (n=33), parietal lobes (n=7), temporal lobes (n=12), basal ganglia regions (n=12), thalamus (n=3), and pons (n=5). The case detection rate of X-Map for AIS was similar to that of CTP (p=0.151) but was significantly higher than that of CTA (p<0.001). In terms of diagnostic efficacy, among the total 66 patients enrolled, X-Map achieved a higher diagnostic sensitivity (85%) than CTP and CTA. However, CTP achieved the best diagnostic specificity (84.6%) and diagnostic accuracy (77.4%) among the diagnostic tools used. CONCLUSION: X-Map provides a better or equal clinical value for the diagnosis of AIS as compared to CTA and CTP, respectively, highlighting its potential in clinical applications.