RESUMO
BACKGROUND AND OBJECTIVE: Methionyl-tRNA synthetase (MARS) and A variant of Aminoacyl-tRNA synthetase interacting multifunctional protein 2 (AIMP2) with an exon 2 deletion (AIMP2-DX2) are known to be overexpressed in lung cancer. However, their role as diagnostic markers in lung cancer has not been well established. Thus, we evaluated their diagnostic performance in brushed cells obtained from nodular lung lesions suspected of lung cancer. METHODS: Samples obtained by radial endobronchial ultrasound-guided brushing were processed for cytological examination with Papanicolaou (Pap) staining. Then, double IF staining with MARS and AIMP2-DX2 antibodies was measured in the cytology samples for peripheral lung nodules. The diagnostic performance was compared against biomarkers. RESULTS: MARS IF staining was the only independent staining method used for the prediction of malignant cells. The area under the curve (AUC) of conventional cytology, MARS IF, and MARS IF plus cytology was 0.64, 0.68, and 0.69, respectively. The diagnostic accuracy was increased in MARS IF plus conventional cytology compared with cytology alone (71% vs. 47%). CONCLUSIONS: The combination of MARS staining with conventional cytology showed increases in the diagnostic accuracy for diagnosing lung nodules suspected of lung cancer on chest-computed tomography scans.
RESUMO
Cytological specimens from computed tomography (CT)-guided needle aspiration biopsy (CT-NAB) have relatively low sensitivity for lung cancer diagnosis. This study evaluated the usefulness of the dual immunofluorescence (IF) staining method using methionyl-tRNA synthetase (MARS), aminoacyl-tRNA synthetases interacting multi-functional protein-lacking exon 2 (AIMP2-DX2), and pan-cytokeratin (pan-CK) obtained from clinical specimens. One-hundred forty-five cytology specimens were prospectively collected from patients who underwent CT-NAB under the suspicion of lung cancer. The results of two combinations of MARS, AIMP2-DX2, and pan-CK dual IF staining were compared with those of conventional cytology by calculating the area under the curve (AUC). The results of combining dual IF with conventional cytology showed higher AUC than conventional cytology alone: cytology/MARS/AIMP2-DX2 (0.891 vs. 0.829, P = 0.003), cytology/MARS/pan-CK (0.916 vs. 0.829, P < 0.001), and cytology/AIMP2-DX2/pan-CK (0.877 vs. 0.829, P = 0.005). In specimens with non-diagnostic results in conventional cytology, MARS/AIMP2-DX2 dual IF staining showed sensitivity, specificity, and AUC of 60.0%, 86.4%, and 0.79, respectively. The dual IF staining method using two combinations of MARS, AIMP2-DX2, and pan-CK is an effective diagnostic tool that can improve the lung cancer diagnostic yield by complementing conventional cytology.
RESUMO
A 65-year-old woman was treated for an atypical radiological presentation of spinal tuberculosis. Compared with previously reported cases, the following two different radiographic features were found. 1) Although there was multiple and skipped involvement of the vertebral body, the intervertebral disc was relatively preserved. 2) The presence of an epidural granuloma indicated an epidural extension of the lesion of the adjacent vertebral body. These findings strongly mimicked bone marrow infiltrative disease such as a malignancy. Tuberculosis was confirmed through an open biopsy and the patient was treated successfully with antitubercular chemotherapy. This case highlights the importance of being aware that spinal tuberculosis has many different radiographic features and can mimic a spinal malignancy.
