No abstract available

[en] Temperature dependences of β-ray-excited radioluminescence and uv-light-excited photoluminescence were measured in anthracene crystals. They depend on crystals, but their ratio shows the same characteristic in all of the crystals. Large temperature dependence of the ratio cannot be explained by the three relaxation processes of highly excited states, i.e. internal conversion and vibrational relaxation, autoionization (preionization) and exciton fission. It is expected by analyzing the data that there must exist a radiationless decay with an activation energy --0.048 eV in the relaxation manifolds. Predissociation to a geminate radical pair, which is followed by radiationless geminate recombination to an anthracene molecule or fission to isolated radicals, is considered as a competing process with the above three physical processes. (author)

[en] To improve the accuracy of T3 diagnosis in lung cancer, Pneumothorax CT was carried out in four patients having diagnosis of plain CT and enhanced CT. Both plain and enhanced CT demonstrated obliteration of low density zone between tumor and the aorta in all cases. In three of four cases, Pneumothorax CT, however, demonstrated free air space where tumor was evaluated to be invaded. Remaining one presented the loss of such free air space even by Pneumothorax CT and was made the diagnosis of aortic invasion, which was confirmed by surgicopathological finding. Pneumothorax CT is useful for the diagnosis of ruling out tumor invasion to the aorta. (author)

[en] The diagnostic value of the tomogram of digital radiography (CR tomogram) was evaluated in comparison with that of the xerotomogram in 33 patients with small peripheral-type lung lesions, including 22 who were operated on. The margin of the lesions, pleural retraction, involved bronchi, involved vessels, cavity formations and other abnormalities were as clearly visualized by CR tomography as by xerotomography. The thickness of the third or fourth order bronchi could also be observed on the CR tomogram. The CR tomogram proved to be of as much value as the xerotomogram for the diagnostic delineation of the features of peripheral-type lung lesions. (author)

[en] We studied CT and mediastinoscopy as methods for preoperatively diagnosing mediastinal lymph node metastases (N2) in 133 resected lung cancers, and determined the optimal criterion for a CT diagnosis based on node size. All 133 patients were examined with CT, with a resulting sensitivity of 57% and specificity of 81%. The optimal CT criterion for metastasis was a short node axis of ≥10 mm. Where nodes with short axes of ≥20 mm, for squamous cell carcinoma, and ≥15 mm, for adenocarcinoma, were selected, 100% specificity was obtained. It can thus be considered that nodes of this size on CT show definite metastatic disease. Thirty-three patients who satisfied the selection criteria out of a total of 80 patients underwent mediastinoscopy as a clinical trial, with a sensitivity of 70% and a specificity of 100%. Of these, the nine CT false positives (eight squamous cell carcinomas) and three out of the six CT false negatives (all adenocarcinomas) were properly diagnosed. We compared 80 cases diagnosed as N2 by CT alone and by CT plus mediastinoscopy, and obtained the following results: accuracies of 67.5 and 82.5%, sensitivities of 54 and 67% and specificities of 73 and 89%, respectively, showing the addition of mediastinoscopy significantly to improve the diagnosis of N2 disease (P=0.03). We now routinely include a mediastinoscopy except in cases where greatly enlarged nodes are visible on X-ray or in patients who are not candidates for neoadjuvant chemotherapy. (author)

[en] The purpose of this study was to evaluate the usefulness of computed tomographic (CT) fluoroscopy-guided transthoracic needle biopsy (TTNB) with an 18-gauge automatic biopsy gun for the diagnosis of pulmonary nodules. Between March 1996 and January 1998, 50 patients in whom pulmonary lesions could not be diagnosed cytopathologically with fiberoptic bronchoscopy or were not clearly visualized with fluoroscopy underwent CT fluoroscopy-guided TTNB. Final pathological diagnoses were 23 lung carcinomas, five pulmonary metastases and 22 benign lesions. Sufficient tissue for analysis was obtained from 48 of the 50 lesions (96%). The overall diagnostic yield of CT fluoroscopy-guided TTNB was 90%. The sensitivity, specificity and accuracy for malignancy were 89%, 100% and 94%, respectively. In 20 of the 22 cases (91%) of benign lesions, histological analysis yielded correct and specific diagnoses. Complications occurred in 22 of the 50 cases (44%). The most common complication was pneumothorax, which occurred in 21 of the 50 cases (42%). Chest tube insertion was required in 6 (12%). Although CT fluoroscopy could not decrease the complication rate, CT fluoroscopy-guided TTNB with an automatic biopsy gun appears to be a promising technique for diagnosing pulmonary lesions, particularly benign lesions. (author)

[en] Axial multiplanar reconstruction CT using the interpolation technique (AMPR-CT) permits continuous axial images to be cine-displayed and visualized 3-dimensionally. We performed AMPR-CT for 26 patients with pulmonary nodules who underwent surgical resection (15 cases of lung cancer) in order to evaluate the relationships between lesions and surrounding structures, particularly vessels and bronchi, and to assess the effectiveness of AMPR-CT. AMPR-CT, film-based CT (Conv. CT) and CR tomography were compared against resected specimens with regard to the relationships between lesions, vessels and bronchi. AMPR-CT was significantly superior to Conv. CT and CR tomography in detecting involvement of pulmonary vessels. Involvement of pulmonary veins was seen in all resected lung cancers, where as such involvement was seen in only one of 8 non-neoplastic lesions. Thus, involvement of pulmonary veins is strongly suggestive of malignancy (p<0.001). AMPR-CT permits pulmonary nodules to be visualized 3-dimensionally and allows morphological assessment. AMPR-CT is a useful technique that improves CT's diagnostic capabilities. (author)

[en] The clinical features of intrathoracic recurrence detected by chest computed tomography (CT) after surgical resection of lung carcinoma and the diagnostic ability of CT were examined. Chest CT scans were retrospectively compared with plain chest X-ray films that were available at the time of CT. In 109 patients who had undergone surgical resection, intrathoracic recurrences at 116 sites were detected by chest CT. Of the recurrent lesions, 47% (54 of 116) were pulmonary metastases and 30% (35 of 116) were lymph node metastases. According to histologic type, 42% (18 of 43) of squamous cell carcinoma recurred in the lymph nodes and 56% (35 of 62) of adenocarcinomas metastasized to the lung. In cases of stage I disease, 36% (5 of 14) of squamous cell carcinomas metastasized to lymph nodes and 50% (7 of 14) metastasized to lungs, 5% (1 of 19) of adenocarcinomas metastasized to lymph nodes and 84% (16 of 19) metastasized to lungs. Although 61% (33 of 54) of pulmonary metastases and 67% (8 of 12) of pleural metastases detected by chest CT were visible on chest X-ray films, only 14% (5 of 35) of lymph node metastases and none of stump recurrence detected by chest CT were also detected on chest X-ray films. Chest CT was statistically more helpful for detecting recurrences than chest X-ray (p<0.05). However, it was often difficult to distinguish among lymph node recurrence, postoperative reactive change and stump recurrence, and between solitary pulmonary metastasis and double cancer. (author)

[en] We sought to determine the volume of each anatomic lung lobe reconstructed using paired inspiratory and expiratory three-dimensional CT (3D-CT) imaging and compare these to pulmonary function test results for 20 chronic obstructive plumonary disease (COPD) patients. The combination of inspiratory and expiratory 3D-CT improved correlation coefficients between forced expiratory volume 1.0 (FEV_1.0) and 3D-CT index. In addition, pulmonary function results were primarily affected by the normal lobar volumes of the lower lobes. (author)

[en] 

Background

For thymic epithelial tumors (TETs), the National Comprehensive Cancer Network guideline has suggested that complete excision of the tumor should be performed without a preoperative biopsy when resectable. However, little evidence has been provided to support this strategy. The purpose of this study was to review our diagnostic process and to evaluate the validity of radical resection of anterior mediastinal masses (AMMs) without pathological confirmation.

Methods

A total of 254 patients underwent surgical resection for AMMs between 2004 and 2015. This study included 181 patients with likely TETs according to clinical features, serum levels of tumor markers and autoimmune-antibodies, and radiological findings. In addition, AMMs likely TETs were classified into resectable or unresectable tumors. We retrospectively reviewed the diagnostic process of those patients and validated surgical resection of AMMs without a definitive diagnosis.

Results

Among 254 patients, 181 were suspected of having a TET based on the serum levels of tumor markers and autoimmune-antibodies and the radiological findings. Of them, 157 patients were deemed resectable and underwent surgical resection without histological confirmation, and 144 (92%) were diagnosed with TETs in the final pathological examinations. In 13 patients with non-TETs, the tumors were difficult to differentiate from TETs by imaging and clinical findings alone.

Conclusions

A total of 92% of patients suspected of having a TET and who underwent complete resection without pathological confirmation were accurately diagnosed and properly treated. Surgical resection without a definitive diagnosis was feasible in patients suspected of having a TET when they were considered resectable.