A case of intracystic papillary carcinoma accompanying widespread ductal carcinoma in situ.

A 39-year-old Japanese woman noticed a right breast tumor in July 2004. Mammography (MMG) demonstrated an oval tumor without calcification. Dynamic Magnetic Resonance Imaging (D-MRI) demonstrated a high-intensity mass on T2-weighted images, showing mild enhancement during the arterial phase and persistent enhancement during the arterial late phase. Core needle biopsy revealed papillary carcinoma suggestive of Intracystic Papillary Carcinoma (IPC). Auchincloss operation was performed following a partial mastectomy, as the surgical margin after partial mastectomy was positive for carcinoma. Histopathologic mapping of her right breast revealed wide and extensive intraductal spread of DCIS around the IPC. IPC was originally reported to be a localized non-invasive mammary carcinoma. But approximately, half of IPC cases are associated with invasive carcinoma or DCIS beyond the tumor. Careful selection of operative procedure is needed after localized non-invasive IPC or IPC associated with DCIS around the main tumor or invasive carcinoma is diagnosed.

Application of subsecond rotation scan to helical CT for lung cancer screening.

PURPOSE: To clarify whether the benefit of a reduced effective scan width obtained using a smaller pitch outweighs the disadvantage of increased noise in the application of a subsecond helical CT to mass screenings for lung cancer. MATERIALS AND METHODS: Twenty-two helical CT scans of the lung were obtained in 11 healthy subjects using the following parameters: 1) scan 1 was performed at 120 kVp, 50 mA, 10-mm collimation, 1-second/rotation, helical pitch of 2.0; and 2) scan 2 was performed at 120 kVp, 50 mA, 10-mm collimation, 0.75-second/rotation, helical pitch of 1.5. Computer-generated nodules measuring 10 mm and 6 mm in diameter showing ground-glass opacity were superimposed on these images. The detectability of each nodule was evaluated by six blinded readers using ROC analysis. RESULTS: Detectability of the 6-mm nodules was significantly higher in scan 2 than in scan 1. Detectability of the 10-mm nodules was not significantly different between scans 1 and 2. CONCLUSION: The use of a smaller pitch by employing a subsecond rotation scan in a helical CT for lung cancer screenings improves the detection of small lesions without increasing either the scanning time or radiation dose.

Intra- and interobserver agreement and performance score of breast phantom image interpretation: influence of ambient room lighting levels.

The influence of ambient room lighting conditions on soft-copy breast phantom image interpretation was evaluated by comparing cathode ray tube (CRT) monitors with liquid crystal displays (LCDs). Nine observers were asked to use a three-point scale to rate the visibility of various phantom objects (masses, specks, and fibers) displayed on a 21-inch CRT (2,560 x 2,048) and a 21-inch LCD (2,560 x 2,048) under three different levels of ambient lighting (20, 100 and 420 lux at the display center). Each phantom image was interpreted twice, and the reproducibility of judgment and inter-observer agreement was evaluated using kappa statistics. Except for the "mass" score, the LCD score showed a significantly higher value (p<0.05) compared with that of CRT. Nevertheless, no significant differences were found among the three lighting levels. Furthermore, intra- and inter-observer agreement in judgments showed no effects of room illumination. Although the breast phantom objects were better visualized on LCDs than on CRT monitors, room illumination did not affect the performance score of soft-copy reading.

Multi-slice CT of thyroid nodules: comparison with ultrasonography.

PURPOSE: To evaluate the usefulness of multi-slice computed tomography (MSCT) in comparison with ultrasonography (US) for the differentiation of benign from malignant thyroid nodules and the evaluation of tumor extension. MATERIALS AND METHODS: Thirty patients with thyroid nodules (14 malignant, 16 benign) who underwent both MSCT and US participated in the present study. MSCT with contrast enhancement was performed, and 3D shaded volume rendering (SVR) and multiplanar reconstruction (MPR) were employed to differentiate benign from malignant nodules and to evaluate tumor extension. US images were obtained using a 7.5 MHz annular array probe. A three-point rating scale was used for image interpretation, and the kappa statistic was employed to evaluate agreement between MSCT and US. RESULTS: Sensitivity in differentiating benign from malignant nodules was found to be 85.7% for US and 78.6% for MSCT. Disagreement between MSCT and US occurred in assessing the homogeneity of the solid component and the presence of fibrous capsule. In two of seven T4 cases, MPR provided a more accurate diagnosis than US examination in detecting extracapsular invasion. CONCLUSION: For differential diagnosis of thyroid nodules, US was found to be better than MSCT. However, MSCT could be useful for the evaluation of advanced cases with suspicion of extracapsular extension.

Diagnostic value of curved multiplanar reformatted images in multislice CT for the detection of resectable pancreatic ductal adenocarcinoma.

The purpose of this study was to assess the usefulness of curved multiplanar reformatted (MPR) images obtained by multislice CT for the depiction of the main pancreatic duct (MPD) and detection of resectable pancreatic ductal adenocarcinoma. This study included 28 patients with pancreatic carcinoma (size range 12-40 mm) and 22 without. Curved MPR images with 0.5-mm continuous slices were generated along the long axis of the pancreas from pancreatic-phase images with a 0.5- or 1-mm slice thickness. Seven blinded readers independently interpreted three sets of images (axial images, curved MPR images, and both axial and curved MPR images) in scrolling mode. The depiction of the MPD and the diagnostic performance for the detection of carcinoma were statistically compared among these images. MPR images were significantly superior to axial images in depicting the MPD, and the use of both axial and MPR images resulted in further significant improvements. For the detection of carcinoma, MPR images were equivalent to axial images, and the diagnostic performance was significantly improved by the use of both axial and MPR images. High-resolution curved MPR images can improve the depiction of the MPD and the diagnostic performance for the detection of carcinoma compared with axial images alone.

Interobserver agreement and performance score comparison in quality control using a breast phantom: screen-film mammography vs computed radiography.

Our objective was to evaluate interobserver agreement and to compare the performance score in quality control of screen-film mammography and computed radiography (CR) using a breast phantom. Eleven radiologists interpreted a breast phantom image (CIRS model X) by four viewing methods: (a) original screen-film; (b) soft-copy reading of the digitized film image; (c) hard-copy reading of CR using an imaging plate; and (d) soft-copy reading of CR. For the soft-copy reading, a 17-in. CRT monitor (1024x1536x8 bits) was used. The phantom image was evaluated using a scoring system outlined in the instruction manual, and observers judged each object using a three-point rating scale: (a) clearly seen; (b) barely seen; and (c) not seen. For statistical analysis, the kappa statistic was employed. For "mass" depiction, interobserver agreement using CR was significantly lower than when using screen-film ( p<0.05). There was no significant difference in the kappa value for detecting "microcalcification"; however, the performance score of "microcalcification" on CR hard-copy was significantly lower than on the other three viewing methods ( p<0.05). Viewing methods (film or CR, soft-copy or hard-copy) could affect how the phantom image is judged. Paying special attention to viewing conditions is recommended for quality control of CR mammograms.

Lung: feasibility of a method for changing tube current during low-dose helical CT.

A method for changing the tube current during helical scanning was applied to low-dose computed tomography (CT) in the lung. The changing method resulted in significant equalization of image noise in various lung sections compared with that at scanning with constant tube current. Detectability of nodules was equivalent between 60 mA and the changing method, whereas degradation occurred at 20 mA. This method seems feasible for the low-dose CT of lung cancer screening.