Imaging and Clinicopathological Features of Acinar Cell Carcinoma

Background

Acinar cell carcinoma (ACC) is a rare pancreatic epithelial malignancy that poses a significant threat. However, there are few related clinical studies. The present study aimed to analyze the imaging and pathological features of ACC to provide a reference for better diagnosis and treatment planning.

Methods

Thirty-nine with ACC, referred to Qianfoshan Hospital, Qilu Hospital and Provincial Hospital in Shandong Province from December 2012 to December 2020, were enrolled. Their imaging and clinicopathological features were analyzed. They were followed up for 1 year, and Cox regression was used to analyze the factors affecting patient prognosis.

Results

ACC was more common in the middle-aged and elderly and peaked at approximately 60 years. The clinical manifestations of the patients were mostly flatulence and upper abdomen pain. The tumor was located in the head of the pancreas in 19 cases, with an average size of 5.8 cm. We found nerve invasion and liver metastasis in one case each. 8 patients showed irregular amorphous tumor calcification on plain computed tomography and 5 showed high and low signals on T1- and T2-weighted images, respectively. Immunohistochemistry revealed 100.0% positive rates for CK, β-catenin, and Ki-67. Thirty-three patients underwent surgical resection, and the 2-year overall mortality rate was 25.6%. Cox analysis revealed that smoking was an independent risk factor affecting patient prognosis.

Conclusion

An in-depth understanding of the imaging and clinicopathological features of ACC is conducive to better diagnosis and treatment planning for ACC and subsequent improvement in patient prognosis.

Analysis of contrast-enhanced spectral chest CT optimal monochromatic imaging combined with ASIR and ASIR-V

OBJECTIVE

The aim of the study was to explore the application of spectral chest CT optimal monochromatic imaging combined with ASIR and ASIR-V to optimize the image quality in the arterial phase.

PATIENTS AND METHODS

62 patients who had undergone contrast-enhanced chest CT examination using spectral CT were included. Twelve sets of arterial phase images were acquired using GSI mode. The CNR, BHA values and subjective scores were statistically analysed. Thus, optimal monochromatic images were obtained. Then, the images were acquired by reconstruction using ASIR and ASIR-V at 30%, 50% and 70% levels. Six sets of images were obtained and compared with QC and the monochromatic image under FBP mode.

RESULTS

In FBP mode, the CNR of 80-keV images was 7.7±2.0, showing no significant difference with QC images (p > 0.05). The BHA value in the blood vessels was 45.2±23.1, which was lower than that in QC images (p < 0.05). The subjective image quality score of 80-keV images was 4.50±0.62. No significant difference was found in QC images (p > 0.05). The subjective score of the artefacts was 2.45±0.62, which was lower than that of QC images (p < 0.05). Thus, 80 keV was chosen as the optimal monochromatic energy to be reconstructed with ASIR and ASIR-V. The CNR of the 80keV+50% ASIR-V group was 13.9±4.3, which was higher than those of 140-kVp and 80-keV images in FBP (p < 0.05). The subjective score was 4.90±0.298, which was higher than that of other groups (p < 0.05).

CONCLUSIONS

Compared with conventional chest CT images in the arterial phase, 80keV+50% ASIR-V images can effectively eliminate beam-hardening artefacts and improve image quality.

Preliminary application of multiple parameters spectral CT in the diagnosis of ovarian cancer

The aim of the study was to evaluate the effectiveness of spectral CT in the diagnosis of ovarian cancer. We retrospectively analyzed the data of 22 patients with spectral CT enhanced scan. The patients were divided into 2 groups: ovarian cancer group (n = 11) and benign tumor group (n = 11), according to the pathologic results. CT values at 40 keV, iodine concentration (IC), water concentration (WC) and spectral curve slope (λHU) of arterial phase and venous phase in the tumors of 2 groups were measured with gemstone spectral imaging (GSI) post-processing software. The independent samples t test was used to compare these multiple parameters above between 2 groups. For the parameters which showed statistically different, the ROC curves were further generated to calculate their diagnostic effectiveness respectively. According to the results, CT values at 40 keV, IC and λHU measured in arterial and venous phases were higher in ovarian cancer group than those in benign tumor group. There were significant differences between these 2 groups (P < 0.05). While WC had no significant difference in these 2 groups (P > 0.05). CT values at 40 keV, IC and λHU had high effectiveness to the diagnosis of ovarian cancer according to ROC curves. The optimal parameter among them was IC in arterial phase with AUC of 0.90. Using 10.92 (100 ug/cm3) as a threshold value, the sensitivity and specificity for diagnosis were 88.9% and 94.7%. Thus, we concluded that spectral CT with multiple parameters was valuable in the diagnosis of ovarian cancer.