Inconclusive Result from CT Guided Transthoracic Needle Aspiration and Biopsy: Affecting Factors and Final Outcome

PURPOSE: Inconclusive results from computed tomography (CT)-guided transthoracic needle aspiration and biopsy (TNAB) performed for lung lesions presents a clinical dilemma. The purpose of this study was to determine the factors affecting an inconclusive result from a CT guided TNAB, and to evaluate the final outcomes of these inconclusive results. MATERIALS AND METHODS: The medical records and radiologic features of 331 patients with lung lesion who received CT guided TNAB were analyzed retrospectively. The results of the TNAB were classified as conclusive (malignancy or specific benign diagnosis) or inconclusive (nonspecific benign or nondiagnostic). RESULTS: Of the 331 cases, 269 (81.3%) were diagnosed as a malignancy (210) or a specific benign lesion (59) after the first TNAB. The remaining 62 (18.7%) were inconclusive. Benign disease, a lesion size < or =15 mm, and morphology of the consolidation type were features significantly correlated with inconclusive results. Of these 62 inconclusive cases a second TNAB was performed in 23, and conclusive diagnoses were obtained in 19 (82.6%). Surgery or radiographic follow up was done in other cases. Finally, among the 62 inconclusive results on the first CT guided TNAB, 16 lesions were diagnosed as malignant, 26 were classified as specific benign disease, and the remaining 20 were defined as nonspecific inflammation. Age over 50 and morphology of a nodule or a mass type were significantly correlated with a malignancy in these 62 cases with inconclusive results on the first TNAB. CONCLUSION: A final diagnosis of benign disease was significantly higher after the CT guided TNAB was inconclusive for lesions < or =15 mm that had consolidation type morphology. Despite the application of core biopsy procedures, there continue to be appreciable numbers of inconclusive results after the first CT guided TNAB. A repeat CT guided TNAB had a high diagnostic yield in these cases and therefore should be considered for cases with inconclusive results.

Primary Mediastinal Synovial Sarcoma

We report a rare case of a primary mediastinal synovial sarcoma. A 44-year-old man had a well-defined tumor in the left posterior mediastinum involving the left lower lobe of the lung, as detected on chest computed tomography, and underwent an en bloc excision and a left lower lobectomy. Grossly, the tumor measured 8.0 cm in the greatest diameter, with a solid and tan-white cut surface. Histologically, the tumor was mainly composed of spindle-shaped cells with a few foci of epithelial differentiation. Immunohistochemical studies were focally positive for cytokeratin, and diffusely positive for vimentin and bcl-2. Epithelial membrane antigen, S-100 protein, desmin, smooth muscle actin, calretinin, and CD34 were all negative. The SYT-SSX1 gene fusion transcript was detected by a reverse transcription- polymerase chain reaction, which was diagnostic of primary synovial sarcoma of the mediastinum. We also reviewed the literature with regard to the clinicopathologic, immunohistochemical, and molecular studies of primary intrathoracic synovial sarcoma

The Magnetic Relaxation Properties of DTPA-bis(4-carboxycyclohexyl) amide Paramagnetic Gd-chelates

PURPOSE: To evaluate the NMR relaxation properties of newly developed high performance paramagnetic. MATERIALS AND METHODS: 4-aminomethylcyclohexane carboxylic acid (0.63 g, 4 mmol) was mixed with the suspension solution of DMF (15 mL) and DTPA-bis-anhydride (0.71 g, 2 mmol) to synthesize the ligand. The ligand was then mixed with Gd2O3 (0.18 g, 0.5 mmol) to synthesize Gd-chelate. For the measurement of magnetic relaxivity of paramagnetic compounds, the compounds were diluted to 1mM and then the relaxation times were measured at 1.5T(64 MHz). Inversion-recovery pulse sequence was employed for T1 relaxation measurement and CPMG(Carr-Purcell-Meiboon-Gill) pulse sequence was employed for T2 relaxation measurement. Using MATLAB(Version 7.1) program, T1 magnetic relaxation map, R1 map, T2 magnetic relaxation map and R2 map were developed to represent magnetic relaxation time and magnetic relaxivity as image. RESULTS: Compared to R1=4.9 mM(-1) sec(-1) and R2= 4.8 mM(-1) sec(-1) of Omniscan (Gadodiamide), which is commercially available paramagnetic MR agent, R1 of SUK090(Gd-C32H74N5O24) was 12.46 mM(-1) sec(-1) and R1 of SUK091(Gd-C34H78N5O24) was 12.77 mM(-1) sec(-1). However, R1 of SUK092(Gd-C30H56N5O17) was decreased to 2.09 mM(-1) sec(-1). In case of R2, SUK090(Gd-C32H74N5O24) was 8.76 mM(-1) sec(-1) and SUK091(Gd-C34H78N5O24) was 7.60 mM(-1) sec(-1) whereas SUK092(Gd-C30H56N5O17) CONCLUSION: Among three new paramagnetic complexes, SUK090(Gd-C32H74N5O24) and SUK091(Gd-C34H78N5O24) showed higher T1, T2 magnetic relaxation rates than that of commercially available paramagnetic MR agent and thus expected to have more contrast enhancement effect.