Low-dose gemcitabine plus nab-paclitaxel versus standard-dose gemcitabine plus nab-paclitaxel in elderly patients with metastatic pancreatic cancer: A randomized Phase II trial.

Background and Aim: A multicenter, open-label randomized Phase II trial was conducted to determine whether low-dose gemcitabine plus nab-paclitaxel (GnP) could improve tolerability and show equivalent efficacy to the standard-dose GnP for elderly patients with metastatic pancreatic cancer. Methods: Consecutive patients aged ≥65 years with metastatic pancreatic cancer who presented at one of four Japanese referral centers between November 2016 and January 2021 were enrolled. The 60 patients were randomly assigned to low- or standard-dose groups with a 1:1 ratio. Patients in the low-dose GnP group received gemcitabine at a dose of 250 mg/m2 and nab-paclitaxel at 125 mg/m2. Results: Low-dose GnP significantly decreased the rate of cases requiring dose reduction (16.7% vs 63.3%). The response rate (36.7% vs 33.3%) and progression-free survival (7.3 vs 8 months) were comparable between the low- and standard-dose groups as determined by independent review. The difference in the median overall survival between the two groups was not significant (7.9 vs 12 months). The proportion of patients with hematologic and non-hematologic treatment-related adverse events was comparable between the two groups. Conclusion: Low-dose GnP had an equivalent efficacy to conventional therapy; however, it did not reduce adverse events.

High 18F-FDG Uptake in a Papillary Craniopharyngioma of the Third Ventricle.

ABSTRACT: Craniopharyngioma is a benign tumor classified as grade 1 by the World Health Organization Classification of Tumors of the Central Nervous System. We present a rare case of a high-18F-FDG-avidity papillary craniopharyngioma of the third ventricle. A 65-year-old man underwent CT and MRI examinations for gait disturbance, lower-limb weakness, and urinary incontinence, and an oval solid tumor that extended from the suprasellar region to the third ventricle was identified. 18F-FDG PET/CT showed high accumulation (SUVmax, 22.3) in the tumor. A transventricular endoscopic tumor biopsy led to the diagnosis of papillary craniopharyngioma.

Regional cerebral THK5351 accumulations correlate with neuropsychological test scores in Alzheimer continuum.

Objectives: We evaluated the relationship between regional accumulations of the tau positron emission tomography (PET) tracer THK5351 and cognitive dysfunction in the Alzheimer's disease (AD) continuum. Methods: The cases of 18 patients with AD or mild cognitive impairment (MCI) due to AD who underwent three-dimensional MRI, fluoro-2-deoxyglucose (FDG)-(PET), Pittsburgh compound B (PiB)-amyloid PET, and THK5351-tau PET were analyzed. Their mean age was 70.6±11.3, their mean Mini-Mental State Examination (MMSE) score was 22.3±6.8, and their mean Alzheimer Disease Assessment Scale-Cognitive Subtest (ADAS) score was 12.5±7.3. To determine the correlation between each patient's four imaging results and their MMSE and ADAS scores, we performed a voxel-wise statistical analysis with statistical parametric mapping (SPM). Results: The SPM analysis showed that the bilateral parietotemporal FDG accumulations and MMSE scores were positively correlated, and the bilateral parietotemporal FDG accumulations were negatively correlated with ADAS scores. There were significant correlations between bilateral parietotemporal and left posterior cingulate/precuneus THK5351 accumulations and MMSE/ADAS scores. Conclusion: In the AD brain, THK5351 correlates with neuropsychological test scores as well as or more additional than FDG due to its affinity for both tau and monoamine oxidase-B (MAO-B), and measurements of THK5351 may thus be useful in estimating the progression of AD.

Comparison of Conventional Imaging and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Diagnostic Accuracy of Staging in Patients with Intrahepatic Cholangiocarcinoma.

We aimed to examine the accuracy of tumor staging of intrahepatic cholangiocarcinoma (ICC) by using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET-CT). From January 2001 to December 2021, 202 patients underwent PET-CT, CT, and MRI for the initial staging of ICC in two institutions. Among them, 102 patients had undergone surgical treatment. Ninety patients who had a histopathological diagnosis of ICC were retrospectively reviewed. The sensitivity and specificity of 18F-FDG PET-CT, CT, and magnetic resonance imaging (MRI) in detecting tumors, satellite focus, vascular invasion, and lymph node metastases were analyzed. Ninety patients with histologically diagnosed ICC were included. PET-CT demonstrated no statistically significant advantage over CT and MR in the diagnosis of multiple tumors and macrovascular invasion, and bile duct invasion. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET-CT in lymph node metastases were 84%, 86%, 91%, 84%, and 86%, respectively. PET-CT revealed a significantly higher accuracy compared to CT or MRI (86%, 67%, and 76%, p < 0.01, respectively) in the diagnosis of regional lymph node metastases. The accuracy of tumor staging by PET-CT was higher than that by CT/MRI (PET-CT vs. CT vs. MRI: 68/90 vs. 47/90 vs. 51/90, p < 0.05). 18F-FDG PET-CT had sensitivity and specificity values for diagnosing satellite focus and vascular and bile duct invasion similar to those of CT or MRI; however, PET-CT showed higher accuracy in diagnosing regional lymph node metastases. 18F-FDG PET-CT exhibited higher tumor staging accuracy than that of CT/MRI. Thus, 18FDG PET-CT may support tumor staging in ICC.

Efficiency of a computer-aided diagnosis (CAD) system with deep learning in detection of pulmonary nodules on 1-mm-thick images of computed tomography.

PURPOSE: To evaluate the performance of a deep learning-based computer-aided diagnosis (CAD) system at detecting pulmonary nodules on CT by comparing radiologists' readings with and without CAD. MATERIALS AND METHODS: A total of 120 chest CT images were randomly selected from patients with suspected lung cancer. The gold standard of nodules ≥ 3 mm was established by a panel of three expert radiologists. Two less experienced radiologists read the images without and afterward with CAD system. Their reading times were recorded. RESULTS: The radiologists' sensitivity increased from 20.9% to 38.0% with the introduction of CAD. The positive predictive value (PPV) decreased from 70.5% to 61.8%, and the F1-score increased from 32.2% to 47.0%. The sensitivity significantly increased from 13.7% to 32.4% for small nodules (3-6 mm) and from 33.3% to 47.6% for medium nodules (6-10 mm). CAD alone showed a sensitivity of 70.3%, a PPV of 57.9%, and an F1-score of 63.5%. Reading time decreased by 11.3% with the use of CAD. CONCLUSION: CAD improved the less experienced radiologists' sensitivity in detecting pulmonary nodules of all sizes, especially including a significant improvement in the detection of clinically important-sized medium nodules (6-10 mm) as well as small nodules (3-6 mm) and reduced their reading time.

Utility of Amplatzer Vascular Plug with Preoperative Common Hepatic Artery Embolization for Distal Pancreatectomy with En Bloc Celiac Axis Resection.

PURPOSE: To evaluate the feasibility and safety of the Amplatzer vascular plug (AVP) for preoperative common hepatic embolization (CHA) before distal pancreatectomy with en bloc celiac axis resection (DP-CAR) to redistribute blood flow to the stomach and liver via the superior mesenteric artery (SMA). MATERIALS AND METHODS: Four patients (3 males, 1 female; median age 69 years) with locally advanced pancreatic body cancer underwent preoperative CHA embolization with AVP. After embolization, SMA arteriography was performed to confirm the alteration of blood flow from the SMA to the proper hepatic artery. RESULTS: In three of four patients, technical successes were achieved with sufficient margin from the origin of gastroduodenal artery. In one patient, the margin was less than 5 mm, although surgery was successfully performed without any problem. Eventually, all patients underwent the DP-CAR without arterial reconstruction or liver ischemia. CONCLUSIONS: AVP application is feasible and safe as an embolic procedure for preoperative CHA embolization of DP-CAR.

Contrast enhancement of intracranial lesions at 1.5 T: comparison among 2D spin echo, black-blood (BB) Cube, and BB Cube-FLAIR sequences.

OBJECTIVES: The purpose of this study was to investigate the usefulness of T1W black-blood Cube (BB Cube) and T1W BB Cube fluid-attenuated inversion recovery (BB Cube-FLAIR) sequences for contrast-enhanced brain imaging, by evaluating flow-related artefacts, detectability, and contrast ratio (CR) of intracranial lesions among these sequences and T1W-SE. METHODS: Phantom studies were performed to determine the optimal parameters of BB Cube and BB Cube-FLAIR. A clinical study in 23 patients with intracranial lesions was performed to evaluate the usefulness of these two sequences for the diagnosis of intracranial lesions compared with the conventional 2D T1W-SE sequence. RESULTS: The phantom study revealed that the optimal parameters for contrast-enhanced T1W imaging were TR/TE = 500 ms/minimum in BB Cube and TR/TE/TI = 600 ms/minimum/300 ms in BB Cube-FLAIR imaging. In the clinical study, the degree of flow-related artefacts was significantly lower in BB Cube and BB Cube-FLAIR than in T1W-SE. Regarding tumour detection, BB Cube showed the best detectability; however, there were no significant differences in CR among the sequences. CONCLUSIONS: At 1.5 T, contrast-enhanced BB Cube was a better imaging sequence for detecting brain lesions than T1W-SE or BB Cube-FLAIR. KEY POINTS: • Cube is a single-slab 3D FSE imaging sequence. • We applied a black-blood (BB) imaging technique to T1W Cube. • At 1.5 T, contrast-enhanced T1W BB Cube was valuable for detecting brain lesions.

Heterogeneity of intratumoral (111)In-ibritumomab tiuxetan and (18)F-FDG distribution in association with therapeutic response in radioimmunotherapy for B-cell non-Hodgkin's lymphoma.

BACKGROUND: The purpose of this study was to quantitatively evaluate the tumor accumulation and heterogeneity of (111)In-ibritumomab tiuxetan (Zevalin®) and tumor accumulation of (18)F-fluoro-deoxyglucose (FDG) and compare them to the tumor response in B-cell non-Hodgkin's lymphoma patients receiving (90)Y-ibritumomab tiuxetan (Zevalin®) therapy. METHODS: Sixteen patients with histologically confirmed non-Hodgkin's B-cell lymphoma who underwent (90)Y-ibritumomab tiuxetan therapy along with (111)In-ibritumomab tiuxetan single-photon emission computerized tomography (SPECT)/CT and FDG positron emission tomography (PET)/CT were enrolled in this retrospective study. On pretherapeutic FDG PET/CT images, the maximum standardized uptake value (SUVmax) was measured. On SPECT/CT images, a percentage of the injected dose per gram (%ID/g) and SUVmax of (111)In-ibritumomab tiuxetan were measured at 48 h after its administration. The skewness and kurtosis of the voxel distribution were calculated to evaluate the intratumoral heterogeneity of tumor accumulation. As another intratumoral heterogeneity index, cumulative SUV-volume histograms describing the percentage of the total tumor volume above the percentage thresholds of pretherapeutic FDG and (111)In-ibritumomab tiuxetan SUVmax (area under the curve of the cumulative SUV histograms (AUC-CSH)) were calculated. All lesions (n = 42) were classified into responders and non-responders lesion-by-lesion on pre- and post-therapeutic CT images. RESULTS: A positive correlation was observed between the FDG SUVmax and accumulation of (111)In-ibritumomab tiuxetan in lesions. A significant difference in pretherapeutic FDG SUVmax was observed between responders and non-responders, while no significant difference in (111)In-ibritumomab tiuxetan SUVmax was observed between the two groups. In contrast, voxel distribution of FDG demonstrated no significant differences in the three heterogeneity indices between responders and non-responders, while (111)In-ibritumomab tiuxetan demonstrated skewness of 0.58 ± 0.16 and 0.73 ± 0.24 (p < 0.05), kurtosis of 2.39 ± 0.32 and 2.78 ± 0.53 (p < 0.02), and AUC-CSH of 0.37 ± 0.04 and 0.34 ± 0.05 (p < 0.05) for responders and non-responders. CONCLUSIONS: Pretherapeutic FDG accumulation was predictive of the tumor response in (90)Y-ibritumomab tiuxetan therapy. The heterogeneity of the intratumoral distribution rather than the absolute level of (111)In-ibritumomab tiuxetan was correlated with the tumor response.

Discordance of motion artifacts on magnetic resonance imaging in Creutzfeldt-Jakob disease: comparison of diffusion-weighted and conventional imaging sequences.

PURPOSE: Motion artifact is problematic in the diagnosis of Creutzfeldt-Jakob disease (CJD) because of dementia. The purpose was to compare the occurrence of this artifact between a diffusion-weighted (DW) magnetic resonance (MR) imaging sequence and conventional sequences. MATERIALS AND METHODS: Ten MR examinations comprising T2-weighted, T1-weighted, DW, and fluid-attenuated inversion recovery imaging in seven CJD patients were retrospectively evaluated. The occurrence of motion artifacts on each sequence were assessed, and the examination was classified into four groups as follows: group A, motion artifact not revealed on DW imaging but revealed on one or more other sequences; group B, revealed on DW imaging and one or more other sequences; group C, not revealed on any sequences; and group D, revealed on DW imaging but not on any other sequences. RESULTS: The 10 MR examinations were classified as eight group A (80%), one B (10%), one C (10%), and zero D (0%). CONCLUSION: Motion artifacts are likely to occur in any conventional imaging sequences in CJD, but the fast-imaging ability of DW imaging can reduce this artifact. The combination of an absence of motion artifact on DW imaging and the presence on conventional sequences may be one of the frequent findings of CJD.

Quantitative evaluation of norcholesterol scintigraphy, CT attenuation value, and chemical-shift MR imaging for characterizing adrenal adenomas.

OBJECTIVE: The objective of our study was to evaluate diagnostic ability and features of quantitative indices of three modalities: uptake rate on norcholesterol scintigraphy, computed tomography (CT) attenuation value, and fat suppression on chemical-shift magnetic resonance imaging (MRI) for characterizing adrenal adenomas. METHODS: Image findings of norcholesterol scintigraphy, CT, and MRI were reviewed for 78 patients with functioning (n = 48) or nonfunctioning (n = 30) adrenal masses. The norcholesterol uptake rate, attenuation value on unenhanced CT, and suppression on in-phase to opposed-phase MRI were measured for adrenal masses. RESULTS: The norcholesterol uptake rate, CT attenuation value, and MR suppression index showed the sensitivity of 60%, 82%, and 100%, respectively, for functioning adenomas of <2.0 cm, and 96%, 79%, and 67%, respectively, for those of >or=2.0 cm. A statistically significant correlation was observed between size and norcholesterol uptake, and between CT attenuation value and MR suppression index. Regarding norcholesterol uptake, the adenoma-to-contralateral gland ratio was significantly higher in cortisol releasing than in aldosterone-releasing adenomas. CONCLUSIONS: The norcholesterol uptake rate was reliable for characterization of adenomas among adrenal masses of >or=2.0 cm. CT attenuation value and MR suppression index were well correlated with each other, and were useful regardless of mass size.