A preliminary investigation of the relationship between 18F-FDG PET/CT metabolic parameters and prognosis in angioimmunoblastic T-cell lymphoma.

Purpose: The goal of the study was to determine the prognostic significance of metabolic parameters in baseline 18F-FDG PET/CT images obtained from patients with angioimmunoblastic T-cell lymphoma (AITL). Methods: Forty patients with pathologically diagnosed AITL who had baseline 18F-FDG PET/CT between May 2014 and May 2021 were assessed as part of this study. Maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), and total metabolic tumor volume (TMTV) were obtained and analyzed. In addition, many relevant features were evaluated, including sex, age, staging, International Prognostic Index (IPI), prediction index for T-cell lymphoma (PIT), Ki-67, and so on. Estimates of progression-free survival (PFS) and overall survival (OS) were determined using the log-rank test and Kaplan-Meier. Results: The median follow-up was 30.2 months (interquartile range 9.82-43.03). Throughout the follow-up period, 29 (72.5%) deaths occurred and 22 (55.0%) patients made progress. The rates for 2- and 3-year PFS were 43.6% and 26.4%, respectively. The 3- and 5-year OS were 42.6% and 21.5%. For TMTV, TLG, and SUVmax, the cut-off values were 87.0 cm3, 711.1, and 15.8, respectively. Poorer PFS and OS were substantially correlated with high SUVmax and TLG. An increased TMTV suggested a shorter OS. TLG performed independently as OS predictors in multivariate analysis. The risk score for predicting the prognosis of AITL includes the TMTV, TLG, SUVmax, and IPI scores, with 4.5 for TMTV, 2 for TLG, 1.5 for IPI scores, and 1 for SUVmax. Three risk categories of patients with AITL had 3-year OS rates of 100.0%, 43.3%, and 25.0%, respectively. Conclusion: Baseline TLG was a strong predictor of OS. Here a new prognostic scoring system for AITL based on the clinical indicators and PET/CT metabolic parameters was constructed, which might make stratification of prognosis easy and also help to individualize treatment.

Prediction of nasal spray drug absorption influenced by mucociliary clearance.

Evaluation of nasal spray drug absorption has been challenging because deposited particles are consistently transported away by mucociliary clearance during diffusing through the mucus layer. This study developed a novel approach combining Computational Fluid Dynamics (CFD) techniques with a 1-D mucus diffusion model to better predict nasal spray drug absorption. This integrated CFD-diffusion approach comprised a preliminary simulation of nasal airflow, spray particle injection, followed by analysis of mucociliary clearance and drug solute diffusion through the mucus layer. The spray particle deposition distribution was validated experimentally and numerically, and the mucus velocity field was validated by comparing with previous studies. Total and regional drug absorption for solute radius in the range of 1 - 110nm were investigated. The total drug absorption contributed by the spray particle deposition was calculated. The absorption contribution from particles that deposited on the anterior region was found to increase significantly as the solute radius became larger (diffusion became slower). This was because the particles were consistently moved out of the anterior region, and the delayed absorption ensured more solute to be absorbed by the posterior regions covered with respiratory epithelium. Future improvements in the spray drug absorption model were discussed. The results of this study are aimed at working towards a CFD-based integrated model for evaluating nasal spray bioequivalence.

Ultrafine particle deposition in a realistic human airway at multiple inhalation scenarios.

The scarcity of regional deposition data in distal respiratory airways represents an important challenge for current toxicology and pharmacology research. To bridge this gap, a realistic airway model extending from nasal and oral openings to distal bronchial airways with varying pathway length was built in this study. Transport and deposition characteristics of naturally inhaled ultrafine particles (UFPs) ranging from 1 to 100 nm were numerically investigated, and effects of different inhalation scenarios were considered. To enable intercase particle deposition comparison, an adjusted parameter, unified deposition enhancement factor (UDEF), was proposed for quantifying the localised deposition concentration. Results show that compartment particle deposition peaked around the ultrafine end of the considered size range, and it dropped rapidly with the increase of particle size. Different inhalation modes caused notable deposition changes in the extrathoracic region, while its effects in the TB airway are much less. For UFPs larger than 10 nm, predicted deposition efficiencies in all compartments are all at lowest levels among considered particle size range, implying UFPs ranging from 10 to 100 nm can travel through the whole respiratory airway model and escape to the alveolar region. Furthermore, high enhancement factors were observed at the vicinity of most bifurcation apexes, and more even UDEF distribution was observed from 1-nm particle cases. While for 100-nm cases, the deposited particles tend to concentrate at few "hot spots" (areas of high deposition concentration in relation to surrounding surfaces) with greater UDEF in the tracheobronchial airway.

Extramedullary hematopoiesis on 18F-FDG PET/CT in a patient with thalassemia and nasopharyngeal carcinoma: A case report and literature review.

Extramedullary hematopoiesis (EMH) occurs in various bone marrow disorders and is most commonly seen in thalassemia and myelofibrosis. Here, we report a patient with beta-thalassemia and nasopharyngeal carcinoma having intrathoracic EMH. Our patient is a 42-year-old man who complained of chest discomfort for a month. He was confirmed nasopharyngeal carcinoma (T3N2M0) by histopathology and received chemoradiotherapy 4 months ago. The patient had a long history of beta-thalassemia and a splenectomy due to splenomegaly at 12 years of age. Computed tomography (CT) scan of the chest showed multiple soft tissue masses in bilateral thoracic cavities. 18F-FDG-PET showed no obvious increase of fluorodeoxyglucose (18F-FDG) uptake by the lesions, with an SUVmax value of approximately 2.19. These lesions were considered EMH. The patient had been followed up for more than 1 year, and there were no changes of the lesions in the thoracic cavities.

Imaging appearance of a singular metastatic adenoid cystic carcinoma of the right kidney: A case report and literature review.

Renal metastasis of a submandibular gland adenoid cystic carcinoma is clinically rare when it presents with an atypical imaging appearance of singular renal metastases. Whole-body positron emission tomography (PET)/computed tomography (CT) can determine whether the singular renal mass is benign or malignant and identify metastases in other parts of the body, particularly in uncommon sites. In the present case, the patient developed a rare partial metastasis to the right kidney three years after undergoing a surgery for submandibular gland adenoid cystic carcinoma. Based on the present case, whole-body PET/CT examination could provide an important basis for making treatment plans for singular renal metastases.

The value of 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography in the detection and characterization of soft tissue metastasis.

Metastatic tumours presenting as soft tissue metastasis (STM) are relatively rare. STM represents metastasis to the muscle and subcutaneous tissues. The majority of the currently available clinical or radiological data on STM consist of isolated case reports or reviews. The aim of this study was to report the manifestations, origin and distribution of STM detected by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) and to assess the value of 18F-FDG PET/CT in the characterisation of STM. We reviewed 17 cases of patients with STM who underwent 18F-FDG PET/CT scanning. The imaging and clinical data of these patients were retrospectively analysed. This method is very sensitive in the detection of STM and provides ample information for clinical tumour staging. PET is more sensitive compared to CT in detecting lesions in muscle, before the density and morphology of the soft tissues are altered, providing a clear view within the soft tissue. Due to the limitations in resolution, PET is less sensitive compared to CT in detecting lesions in the subcutaneous tissues. The aim of this study was to improve our knowledge of 18F-FDG PET/CT findings in the diagnosis of STM and determine its value in the staging of malignant tumours.

Estimation of the displacement of cardiac substructures and the motion of the coronary arteries using electrocardiographic gating.

PURPOSE: The aim of this study was to quantify the displacement of cardiac substructures, including the anterior myocardial territory (AMT), left ventricle, and coronary arteries during a normal cardiac cycle. MATERIALS AND METHODS: Computed tomography (CT) images with retrospective electrocardiographic gating of 17 eligible patients were obtained. All images were reconstructed automatically for the end-diastolic and end-systolic phases. CT scanning without contrast at a random phase and a selected vertebral body were used as references to measure three-dimensionaldisplacements of the cardiac substructures. RESULTS: The displacement between the end-diastolic and end-systolic phases (Dd-s) was greater than that between the end-systolic and random phases and between the end-diastolic and random cardiac phases. The largest displacements for the heart were in the left, posterior, and inferior directions with an average Dd-s of approximately 4-6 mm. The average Dd-s for the AMT and left ventricle was 1.2-2.7 mm in the anterior and right directions, 4.3-7.8 mm in left and posterior directions, and 4.9-6.3 mm in superior and inferior directions. For the coronary arteries, the average Dd-s was 2.8-5.9 mm in the anterior-posterior direction, 3.5-6.6 mm in left-right direction, and 3.8-5.3 mm in the superior-inferior direction. Inter-observer agreement was excellent for the heart, AMT, and left ventricle (kappa coefficient, >0.75 for all) and good for most coronary arteries in three dimensions (kappa coefficient, 0.511-0.687). The Dd-s did not differ significantly between men and women. CONCLUSION: Most average displacements of the cardiac substructures and coronary arteries were 3-8 mm in three dimensions. These findings will be useful to accurately estimate the radiation dose to cardiac substructures during thoracic radiation and to evaluate the risk of radiation-related heart disease.

Fusion PET-CT detection of neurolymphomatosis originating from primary breast lymphoma: A case report and literature review.

Neurolymphomatosis (NL) is an extremely rare manifestation. Involvement of the cranial and peripheral nerves is an unusual manifestation of NL which is occasionally difficult to diagnose using conventional imaging modalities. A 45-year-old female in complete remission from primary breast lymphoma presented with multiple neurological symptoms. (18)F-FDG PET/CT revealed multiple nodular hypermetabolic lesions along the cranial and peripheral nerves, which corresponded to the patient's neurological symptoms. These findings suggest that (18)F-FDG PET/CT successfully detects the infiltration of cranial and peripheral nerves by lymphoma.

Dosimetric comparison of intensity-modulated radiotherapy plans, with or without anterior myocardial territory and left ventricle as organs at risk, in early-stage left-sided breast cancer patients.

PURPOSE: We evaluated heart sparing using an intensity-modulated radiotherapy (IMRT) plan with the left ventricle (LV) and/or the anterior myocardial territory (AMT) as additional organs at risk (OARs). METHODS AND MATERIALS: A total of 10 patients with left-sided breast cancer were selected for dosimetric planning. Both lungs, the right breast, heart, LV, and AMT were defined as OARs. We generated one tangential field plan and four IMRT plans for each patient. We examined the dose-volume histogram parameters of the planning target volume and OARs. RESULTS: Compared with the tangential field plan, the mean dose to the heart in the IMRT plans did not show significant differences; however, the dose to the AMT and LV decreased by 18.7-45.4% and 10.8-37.4%, respectively. The maximal dose to the heart decreased by 18.6-35.3%, to the AMT by 22.0-45.1%, and to the LV by 23.5-45.0%, And the relative volumes of the heart (V≥12), AMT (V>11) and LV (V>10) decreased significantly with different levels, respectively. The volume of the heart, AMT, LV, both lungs, and right breast receiving≥5 Gy showed a significant increase. Compared with the IMRT (H) plan, the mean dose to the heart, AMT, and LV decreased by 17.5-21.5%, 25.2-29.8%, and 22.8-29.8% and the maximal dose by 13.6-20.6%, 23.1-29.6%, and 17.3-29.1%, respectively. The IMRT plans for both lungs and the right breast showed no significant differences. CONCLUSIONS: The IMRT plans with the addition of the AMT and/or LV as OARs considerably increased heart sparing. We recommend including the LV as an additional OAR in such plans.

Correlation between calcified liver metastases and histopathology of primary colorectal carcinoma in Chinese.

The study examined the association between calcified liver metastases and the histopathology of the primary colorectal carcinoma in Chinese. The clinical, pathological and CT data were retrospectively analyzed in 210 patients (mean age: 54.2 years) with liver metastases from colorectal carcinoma. Plain CT scanning and contrast-enhanced scanning were performed in all the patients. For the contrast-enhanced examination, iohexol was injected by using a high pressure syringe at a flow rate of 2.5-3.0 mL/s. The arterial phase lasted approximately 25 s and the portal venous phase about 60 s. All patients had no history of chronic liver diseases and had never received interventional treatments. χ(2)-test was used to analyze the rate of calcification in the liver metastasis from colorectal cancer of different differentiation degrees. Among the 210 cases of liver metastases, 22 patients (10.5%) were found to have calcified liver metastases on CT scan. Two patients with calcified liver metastasis received lumpectomy and developed calcification in recurrent tumors. Another two patients had calcification in newly developed tumor masses. And the calcification in the newly developed masses was similar to that of their primary counterparts in terms of morphology and distribution. On the enhanced CT scan, the tumors exhibited no enhancement during hepatic arterial phase and showed slight rim enhancement during portal venous scan in the 22 cases. The calcification became obscure on contrast-enhanced scans. Histopathologically, the primary tumors were well-differentiated adenocarcinoma in 6 cases, moderately-differentiated adenocarcinoma in 10, poorly-differentiated adenocarcinoma in 4 and mucinous adenocarcinoma in 2 among the 22 cases. No statistical correlation was noted between the incidence of calcified liver metastasis and the pathological subtypes and differentiation degrees of the primary colorectal carcinoma. It was concluded that calcified liver metastases may result from colorectal adenocarcinomata of different differentiation degrees or mucinous adenocarcinomata in Chinese population. There is no correlation between calcification of liver metastases and the pathological subtype of the primary colorectal carcinoma in Chinese, which is different from the findings that calcified metastases were associated with colorectal mucinous adenocarcinoma in other ethnic groups.