Texture Features of 18F-Fluorodeoxyglucose Positron Emission Tomography for Predicting Programmed Death-Ligand-1 Levels in Non-Small Cell Lung Cancer.

Background: Identifying programmed death-ligand-1 (PD-L1) expression is crucial for optimizing treatment strategies involving immune checkpoint inhibitors. However, the role of intratumoral metabolic heterogeneity specifically derived from 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) images in predicting PD-L1 expression in patients with newly diagnosed non-small cell lung cancer (NSCLC) remains unexplored. Here, we investigated the association between FDG PET texture features and PD-L1 expression by retrospectively analyzing the data of patients newly diagnosed with NSCLC who underwent FDG PET/CT scans and PD-L1 immunohistochemical staining before treatment. Methods: Patients were categorized based on their tumor proportion scores (TPSs) into negative-, low-, and high-PD-L1 expression groups. We computed the maximum standardized uptake value and 31 texture features for the primary tumor from PET images and compared differences in parameters among the groups. Results: Of the 83 patients, 12, 45, and 26 were assigned to the negative-, low-, and high-PD-L1 expression groups, respectively. Six specific texture features (low gray-level run emphasis, short-run low gray-level emphasis, long-run high gray-level emphasis, low gray-level zone emphasis, high gray-level zone emphasis, and short-zone low gray-level emphasis) helped distinguish among all possible combinations. Conclusions: Our findings revealed that FDG PET texture features are potential imaging biomarkers for predicting PD-L1 expression in patients newly diagnosed with NSCLC.

FDG PET texture indices as imaging biomarkers for epidermal growth factor receptor mutation status in lung adenocarcinoma.

Identifying the epidermal growth factor receptor (EGFR) mutation status is important for the optimal treatment of patients with EGFR mutations. We investigated the relationship between 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) texture indices and EGFR mutation status in patients with newly diagnosed lung adenocarcinoma. We retrospectively analyzed data of patients with newly diagnosed lung adenocarcinoma who underwent pretreatment FDG PET/computed tomography and EGFR mutation testing between August 2014 and November 2020. Patients were divided into mutated EGFR and wild-type EGFR groups. The maximum standardized uptake value (SUVmax) and 31 texture indices for the primary tumor were calculated from PET images and compared between the two groups. Of the 66 patients included, 22 had mutated EGFR and 44 had wild-type EGFR. The SUVmax did not significantly differ between the two groups. Among the 31 evaluated texture indices, the following five showed a statistically significant difference between the groups: correlation (P = 0.003), gray-level nonuniformity for run (P = 0.042), run length nonuniformity (P = 0.02), coarseness (P = 0.006), and gray-level nonuniformity for zone (P = 0.04). Based on the preliminary results of this study in a small patient population, FDG PET texture indices may be potential imaging biomarkers for the EGFR mutation status in patients with newly diagnosed lung adenocarcinoma.

An analysis of the left top pulmonary vein and comparison with the right top pulmonary vein for lung resection by three-dimensional CT angiography and thin-section images.

PURPOSE: The right top pulmonary vein (RTPV) is defined as an anomalous branch of the right superior PV (SPV) draining into the PV or left atrium (LA). Several previous reports have described the RTPV, but only a few have mentioned the left top PV (LTPV). The present study aimed to evaluate the branching patterns of the RTPV and LTPV using thin-section CT images and three-dimensional CT angiography (3D-CTA). MATERIALS AND METHODS: This study included 1437 consecutive patients for evaluation of the right side and 1454 consecutive patients for the left side who were suspected of lung cancer and underwent CTA. We assessed the presence of each RTPV and LTPV and their branching patterns on the CTA images. When the RTPV or LTPV was identified, the maximum short-axis diameter was measured. RESULTS: RTPV was found in 9.1% (131/1437), whereas LTPV was found in 2.9% (42/1454) of the patients. RTPV was also observed in 17.1% (7/41) of LTPV cases, except for one case in which the right side could not be evaluated. The most common RTPV inflow site was the right inferior PV (IPV) in 64.9% (85/131) of the patients, whereas that of the LTPV was the left IPV in 100.0% (42/42) of the patients. The mean diameter of the RTPV and LTPV was 3.3 mm (range, 1.3-7.5 mm) and 2.4 mm (range, 0.9-6.3 mm), respectively (P < 0.01). CONCLUSION: The top PV branching pattern variations can be evaluated using thin-section CT and 3D-CTA images. RTPV is not a rare finding, and LTPV should also be identified in lung cancer cases scheduled for resection.

Quantitative [99mTc]Tc-MDP SPECT/CT correlated with [18F]NaF PET/CT for bone metastases in patients with prostate cancer.

BACKGROUND: The purpose of the present study was to elucidate the correlation between standardized uptake value (SUV) and volume-based parameters measured by quantitative [99mTc]Tc-methylene diphosphonate (MDP) single photon emission computed tomography (SPECT)/CT and [18F]-sodium fluoride ([18F]NaF) positron emission tomography (PET)/CT in the assessment of bone metastases in patients with prostate cancer. METHODS: The study included 26 male prostate cancer patients with confirmed or suspected bone metastases who underwent both [99mTc]Tc-MDP SPECT/CT and [18F]NaF PET/CT studies. Skeletal lesions visible on both SPECT/CT and PET/CT were classified as benign or metastases. The maximum SUV (SUVmax), peak SUV (SUVpeak), mean SUV (SUVmean), metabolic bone volume (MBV), and total bone uptake (TBU) were calculated for every lesion showing abnormal uptake. RESULTS: A total of 202 skeletal lesions (147 benign and 55 metastases) were detected in the 26 patients. Strong significant correlations were noted between SPECT/CT and PET/CT for the SUV- and volume-based parameters (all P < 0.001). The SUVmax, SUVpeak, SUVmean, and TBU values obtained with SPECT/CT were significantly lower than the corresponding values obtained with PET/CT (all P < 0.001). The MBV in SPECT/CT was significantly higher than that in PET/CT (P < 0.001). All SUV- and volume-based parameters obtained with both SPECT/CT and PET/CT for metastatic lesions were significantly higher than the corresponding parameters for benign lesions (P values from 0.036 to < 0.001). CONCLUSIONS: These preliminary results demonstrate that the SUV- and volume-based parameters for bone uptake obtained with quantitative SPECT/CT and PET/CT are strongly correlated in patients with prostate cancer. The SUV parameters obtained with SPECT/CT were significantly lower than those obtained with PET/CT, whereas the uptake volume obtained with SPECT/CT was significantly higher than that obtained with PET/CT.

Correlation of epidermal growth factor receptor mutation status and PD-L1 expression with [18F]FDG PET using volume-based parameters in non-small cell lung cancer.

OBJECTIVE: We investigated the relationship between 2-deoxy-2-[18F]fluoro-D-glucose (FDG) PET using volume-based parameters and epidermal growth factor receptor (EGFR) mutation status, programmed death-ligand-1 (PD-L1) expression level, and their combination, in pretreated non-small cell lung cancer (NSCLC). METHODS: FDG PET findings and EGFR mutation status and PD-L1 expression level were investigated retrospectively in 93 patients with newly diagnosed NSCLC (77 adenocarcinomas, 16 squamous cell carcinomas). Tumors were divided into six groups: EGFR mutant/negative PD-L1, EGFR mutant/low PD-L1, EGFR mutant/high PD-L1, EGFR wild/negative PD-L1, EGFR wild/low PD-L1, and EGFR wild/high PD-L1. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) for primary tumor were measured from PET images. The EGFR mutation status and PD-L1 expression level were estimated in tumor tissue specimens and compared with the PET parameters. RESULTS: None of the PET parameters differed significantly between EGFR-mutated and wild-type EGFR. According to the PD-L1 level, significant differences were detected in SUVmax (P = 0.001) and TLG (P = 0.016), but not MTV. Comparing all six groups, significant difference was detected in only SUVmax (P = 0.011). CONCLUSION: Based on the preliminary results of this study, FDG PET may help in the prediction of PD-L1 expression level, but not EGFR mutation status, in patients with newly diagnosed NSCLC. The SUVmax rather than MTV or TLG, may be of value in predicting the six groups according to the combination of EGFR mutation status and PD-L1 expression level.

An analysis of anatomical variations of the left pulmonary artery of the interlobar portion for lung resection by three-dimensional CT pulmonary angiography and thin-section images.

PURPOSE: The purpose of the present study was to analyze the left pulmonary artery (LPA) branching pattern of the interlobar portion using three-dimensional CT pulmonary angiography (3D-CTPA) and thin-section CT images, and to attempt to diagrammatize these patterns. MATERIALS AND METHODS: The study included 320 patients suspected of having lung cancer of the left upper/lower lobe who underwent CTPA. The number and origin of the LPA branches of the interlobar portion, A1 + 2c, A6, and lingular artery from pars interlobaris (PI), were identified meticulously using 3D-CTPA and thin-section images. We then diagrammatized the identified LPA branching patterns of the interlobar portion. RESULTS: The diagrammatized LPA branching patterns of the interlobar portion were broadly classified into seven types in the order of bifurcation from proximal to distal. Type 1 was the most frequent (120/320, 37.5%). PI originated from the lower portion, that is, from A8 or the common trunk of A8 and A9 in 95 cases (29.7%). We could also precisely diagrammatize the LPA branching patterns of the interlobar portion into 85 types in all 320 patients. CONCLUSION: 3D-CTPA and thin-section images provided precise preoperative information regarding the LPA branching patterns of the interlobar portion.

A Case of Glioblastoma With Calcified Region Imaged With 18F-NaF PET/CT.

F-NaF is a bone-seeking positron-emitting tracer with high sensitivity and specificity for detection of osseous lesions. We report a case of primary glial tumor that showed extraosseous uptake on F-NaF PET/CT. CT revealed a mass in the right parietal lobe with calcification. F-NaF PET/CT showed abnormal tracer uptake in the brain tumor, which was subsequently confirmed to be a glioblastoma by histologic examination.

Preoperative Evaluation of the Right Upper Lobe Pulmonary Artery by 3D-CT Pulmonary Angiography vs. Thin-Section Multiplanar Reconstruction Images Obtained by Contrast-Enhanced Multidetector-Row CT.

We compared the effectiveness of 3-dimensional computed tomography pulmonary angiography (3D-CTPA) and thin-section multiplanar reconstruction (MPR) images obtained using contrast-enhanced multidetector row CT (MDCT), in the evaluation of pulmonary artery (PA) branches of the right upper lobe. We studied 127 patients suspected of having lung cancer of the right upper lobe who underwent contrast-enhanced MDCT scans and a right upper lobectomy. We compared the intraoperative findings of the PA branches of the right upper lobe obtained with 3D-CTPA and thin-section MPR images. In 125 (97.7%) patients, one or more PA branches arose from arteries other than the superior trunk. Among 10 (7.9%) patients, a PA branch arose from the middle lobe in one patient and from the superior segment of the lower lobe in the other 9 patients. According to the intraoperative findings, 97.2% and 99.7% of the PA branches were identified by 3D-CTPA and thin-section MPR images, respectively (p ＜ 0.03). The single branch missed by both imaging modalities was 1.0mm in dia. The 8 branches missed only by 3D-CTPA were ＜ 1.4mm in dia. Both the 3D-CTPA and thin-section MPR images provided precise preoperative information regarding PA branches of the right upper lobe. However, the thin-section MPR images appeared to contribute more to the evaluation of smaller PA branches.

11C-PiB PET/CT in nasopharyngeal amyloidosis associated with multiple myeloma.

We present an unusual case of nasopharyngeal amyloidosis associated with multiple myeloma. A 63-year-old woman presented with 2 months' history of epistaxis and dentalgia 3 years after being diagnosed with multiple myeloma. CT and C-Pittsburgh compound B (PiB) PET images demonstrated that the intense C-PiB uptake corresponded to the nasal, paranasal, and palatal area matching the CT mass lesion. Histopathologic examination confirmed amyloidosis.