A case of intermittent CT imaging for up to 2 hours following asymptomatic air emboli due to a CT-guided lung biopsy.

Air emboli represent rare but severe complications of computed tomography (CT)-guided lung biopsy (CTLB). No reports exist regarding the behavior of air during the early stages of air emboli. We present a case of air emboli following CTLB, evaluated by intermittent CT over a 2-hour period, spanning from onset to resolution. A man in his 60s underwent CTLB for diagnosis of a slowly enlarging pulmonary nodule in the right lower lobe. Immediately post-biopsy, chest CT revealed air emboli in the right coronary artery and apex of the ascending aorta. The patient was in the head-down position on the CT table, and intermittent CT scans were performed over a 2-hour period until the air emboli resolved. Subsequently, the patient was discharged without any complications.

Myeloid sarcoma and pathological fracture: a case report and review of literature.

Myeloid sarcoma is a rare clinical entity that presents as an isolated proliferation of leukemic cells, concurrently with or at relapse of acute myeloid leukemia (AML), myelodysplastic syndromes/neoplasms (MDS), chronic myeloid leukemia (CML), and myeloproliferative neoplasm (MPN). Myeloid sarcoma disrupts the normal architecture of its surrounding tissues. When it forms in long bones, it can cause their pathological fracture. We recently experienced a rare case of MDS presenting with myeloid sarcoma in the femur that eventually resulted in its pathological fracture. Detailed chromosomal analysis of the bone marrow cells suggested emergence of myeloid sarcoma during the fast-paced progression of MDS just after acquiring trisomy 22. A comprehensive review of previous cases of myeloid sarcoma-associated pathological fracture indicated possible involvement of structural rearrangements of chromosomes 9 and 22. Management of myeloid sarcoma should continue to improve, and clinicians should note that myeloid sarcoma with specific chromosomal alterations needs extra medical attention to prevent pathological fracture.

N-butyl-2-cyanoacrylate Packing of a Gastroduodenal Artery Pseudoaneurysm due to Distal Pancreatectomy After Subtotal Esophagectomy.

We describe the successful n-butyl cyanoacrylate (NBCA) packing of a large gastroduodenal artery pseudoaneurysm after distal pancreatectomy in a patient with a history of subtotal esophagectomy and gastric tube reconstruction. The pseudoaneurysm was considered to be caused by direct injury to the gastroduodenal artery (GDA). However, embolization of the GDA was not possible in this case because due to prior esophageal surgery, the main blood vessel supplying the gastric tube was the right epigastric artery from the GDA. Packing a pseudoaneurysm with NBCA is a treatment option when preservation of the parent artery is required.

Effects of deep learning on radiologists' and radiology residents' performance in identifying esophageal cancer on CT.

OBJECTIVE: To investigate the effectiveness of a deep learning model in helping radiologists or radiology residents detect esophageal cancer on contrast-enhanced CT images. METHODS: This retrospective study included 250 and 25 patients with and without esophageal cancer, respectively, who underwent contrast-enhanced CT between December 2014 and May 2021 (mean age, 67.9 ± 10.3 years; 233 men). A deep learning model was developed using data from 200 and 25 patients with esophageal cancer as training and validation data sets, respectively. The model was then applied to the test data set, consisting of additional 25 and 25 patients with and without esophageal cancer, respectively. Four readers (one radiologist and three radiology residents) independently registered the likelihood of malignant lesions using a 3-point scale in the test data set. After the scorings were completed, the readers were allowed to reference to the deep learning model results and modify their scores, when necessary. RESULTS: The area under the curve (AUC) of the deep learning model was 0.95 and 0.98 in the image- and patient-based analyses, respectively. By referencing to the deep learning model results, the AUCs for the readers were improved from 0.96/0.93/0.96/0.93 to 0.97/0.95/0.99/0.96 (p = 0.100/0.006/<0.001/<0.001, DeLong's test) in the image-based analysis, with statistically significant differences noted for the three less-experienced readers. Furthermore, the AUCs for the readers tended to improve from 0.98/0.96/0.98/0.94 to 1.00/1.00/1.00/1.00 (p = 0.317/0.149/0.317/0.073, DeLong's test) in the patient-based analysis. CONCLUSION: The deep learning model mainly helped less-experienced readers improve their performance in detecting esophageal cancer on contrast-enhanced CT. ADVANCES IN KNOWLEDGE: A deep learning model could mainly help less-experienced readers to detect esophageal cancer by improving their diagnostic confidence and diagnostic performance.

Successful transcatheter embolization of an unruptured idiopathic peripheral pulmonary artery aneurysm.

Pulmonary artery aneurysms (PAAs) occurring in the distal branch of the pulmonary artery are rare, and there are only a few reports of transcatheter embolization of unruptured idiopathic peripheral PAAs. We report a case of a 66-year-old woman with a history of surgery for pulmonary arteriovenous malformations who presented with an idiopathic peripheral PAA of A10 confirmed by contrast-enhanced computed tomography and pulmonary artery angiography. Transcatheter embolization was performed to prevent rupture, and the aneurysm was successfully embolized. Although there is no consensus on the indications and treatment for unruptured idiopathic peripheral PAAs, transcatheter embolization may be a favorable treatment option.

Preoperative portal vein embolization: a comparison of ethanol and coils versus ethanol alone.

PURPOSE: To compare the efficacy and safety of preoperative portal vein embolization (PVE) with ethanol and coils versus ethanol alone. MATERIAL AND METHODS: Between April 2014 and May 2019, 45 patients underwent right preoperative PVE with ethanol and coils (n = 19; EthCo group) or ethanol alone (n = 26; Eth group). RESULTS: The change in % future liver remnant (FLR) was not significantly different between the EthCo and Eth groups (11.2 ± 4.3% versus 11.3 ± 4.1%, p = .98). Less ethanol was used in the EthCo group (9.7 ± 3.5 mL versus 11.9 ± 4.4 mL, p = .02). Recanalization was observed in eight patients only in the Eth group (p < .01). There were no differences in the pre-/post-PVE laboratory data between the two groups, except for post-PVE albumin. The volume of ethanol used was positively correlated with the post-PVE total bilirubin (p = .01), aspartate aminotransferase (AST) (p < .01) and alanine aminotransferase (ALT) (p < .01) levels. CONCLUSION: The efficacy of PVE did not differ between the EthCo and Eth groups. The use of ethanol and coils was associated with less recanalization and liver damage compared with ethanol alone.

Atypical Neurofibromatous Neoplasm with Uncertain Biologic Potential in the Posterior Mediastinum of a Young Patient with Neurofibromatosis Type 1: A Case Report.

Atypical neurofibromatous neoplasm with unknown biological potential (ANNUBP), proposed in a recent NIH consensus overview, is a rare precursor entity of malignant peripheral nerve sheath tumor (MPNST) in neurofibromatosis type 1 (NF1) patients. Only one report on imaging findings of ANNUBP is available. Herein, we present the case of a 19-year-old female, diagnosed with a mediastinal tumor by chance, who visited to our hospital. She had café-au-lait spots on her trunk and a past history of resected neurofibroma. Her family also had café-au-lait spots; therefore, an NF1-induced tumor was strongly suspected. MRI revealed a paravertebral mass of 7.5 cm in size consisting of an inner rim with low T2 signal intensity and an outer rim with high T2 intensity, which was similar to a target sign, adjacent to the pulmonary veins; the center of the tumor was well enhanced by gadolinium, and the peripheral region was myxoid and slightly enhanced. FDG-PET showed high FDG uptake, SUVmax of 8.5, although the peripheral region represented low FDG accumulation. CT-guided needle biopsy was repeated because of the suspicion of an MPNST, which resulted in the histopathological diagnosis of ANNUBP. Marginal tumor resection was performed, and the final post-resection histopathological diagnosis was ANNUBP transformed from neurofibroma; the region of ANNUBP lost p16 immunostaining, although it was retained in the peripheral region of the neurofibroma. There has been no recurrence or metastasis 1 year after treatment. In conclusion, ANNUBP could be represented as a well-enhanced homogeneous mass on MRI and a high FDG accumulated region on FDG PET/CT, as seen in MPNST, in NF1 patients.

Tumor-associated macrophage-derived inflammatory cytokine enhances malignant potential of malignant pleural mesothelioma.

Malignant pleural mesothelioma (MPM) is an asbestos-related aggressive malignant neoplasm. Due to the difficulty of achieving curative surgical resection in most patients with MPM, a combination chemotherapy of cisplatin and pemetrexed has been the only approved regimen proven to improve the prognosis of MPM. However, the median overall survival time is at most 12 mo even with this regimen. There has been therefore a pressing need to develop a novel chemotherapeutic strategy to bring about a better outcome for MPM. We found that expression of interleukin-1 receptor (IL-1R) was upregulated in MPM cells compared with normal mesothelial cells. We also investigated the biological significance of the interaction between pro-inflammatory cytokine IL-1ß and the IL-1R in MPM cells. Stimulation by IL-1ß promoted MPM cells to form spheroids along with upregulating a cancer stem cell marker CD26. We also identified tumor-associated macrophages (TAMs) as the major source of IL-1ß in the MPM microenvironment. Both high mobility group box 1 derived from MPM cells and the asbestos-activated inflammasome in TAMs induced the production of IL-1ß, which resulted in enhancement of the malignant potential of MPM. We further performed immunohistochemical analysis using clinical MPM samples obtained from patients who were treated with the combination of platinum plus pemetrexed, and found that the overexpression of IL-1R tended to correlate with poor overall survival. In conclusion, the interaction between MPM cells and TAMs through a IL-1ß/IL-1R signal could be a promising candidate as the target for novel treatment of MPM (Hyogo College of Medicine clinical trial registration number: 2973).

Right Lower Lobectomy for an Aberrant Mediastinal Inferior Lobar Artery.

A 74-year-old woman was referred for a right lower lobe consolidation (maximum diameter, 73 mm) pathologically diagnosed as invasive mucinous adenocarcinoma (c-T4 N0 M0, c-stage IIIA). Computed tomography revealed an aberrant mediastinal inferior lobar branch (A6 and common basal artery [A7 to A10]) from the right main pulmonary artery (PA). Right lower lobectomy and lymph node dissection were performed. A mediastinal inferior lobar branch is extremely rare, and this patient with lung cancer underwent right lower lobectomy for all inferior PA branches (A6 and A7 to A10) arising from the main PA into the lower lobe.

EphA2 inhibition suppresses proliferation of small-cell lung cancer cells through inducing cell cycle arrest.

Small-cell lung cancer (SCLC) is characterized by one of neuroendocrine tumors, and is a clinically aggressive cancer due to its rapid growth, early dissemination, and rapid acquisition of multidrug resistance to chemotherapy. Moreover, the standard chemotherapeutic regimen in SCLC has not changed for three decades despite of the dramatic therapeutic improvement in non-SCLC. The development of a novel therapeutic strategy for SCLC has become a pressing issue. We found that expression of Eph receptor A2 (EphA2) is upregulated in three of 13 SCLC cell lines and five of 76 SCLC tumor samples. Genetic inhibition using siRNA of EphA2 significantly suppressed the cellular proliferation via induction of cell cycle arrest in SBC-5 cells. Furthermore, small molecule inhibitors of EphA2 (ALW-II-41-27 and dasatinib) also exclusively inhibited proliferation of EphA2-positive SCLC cells by the same mechanism. Collectively, EphA2 could be a promising candidate as a therapeutic target for SCLC.

Successful Treatment of Pulmonary Pleomorphic Carcinoma with Nivolumab: A Case Report.

Pulmonary pleomorphic carcinoma (PPC) has a poor prognosis due to the poor results of treatment with systemic chemotherapy. We report the case of a 73-year-old woman with PPC who showed a favorable response to nivolumab. As first-line treatment for postoperative recurrence, she received carboplatin and nanoparticle albumin-bound paclitaxel. However, 12 months later, a new metastatic lymph node appeared. Nivolumab was administered as second-line treatment, and the patient showed a favorable prolonged response. The effects of treatment of PPC with nivolumab seem promising. The results of a future prospective study are expected to identify indicators for the treatment of PPC.

Proximal total splenic artery embolization for refractory hepatic encephalopathy.

A Japanese woman with a history of Kasai operation for biliary atresia had living-donor liver transplantation at the age of 22. The first episode of refractory HE and late cellular rejection was treated by a high dose of methylprednisolone. The second episode of refractory HE was treated by balloon-occluded retrograde transvenous obliteration for a spleno-renal shunt. However, the third episode of refractory HE occurred 11 years after liver transplantation. The liver cirrhosis and hypersplenism were present with a Child-Pugh score of C-10. Although portal vein flow was hepatopetal, superior mesenteric vein flow regurgitated. We performed proximal total splenic artery embolization (TSAE). Superior mesenteric vein flow changed to a hepatopetal direction and she became clear. At a year after proximal TSAE, her spleen volume had decreased to 589 mL (20% decrease) on computed tomography. She is well and has a Child-Pugh score of 8 without overt HE. We report the first case of refractory HE treated by proximal TSAE that is a possible less invasive treatment option for a selected patient.

Metabolic response assessment with 18F-FDG-PET/CT is superior to modified RECIST for the evaluation of response to platinum-based doublet chemotherapy in malignant pleural mesothelioma.

PURPOSE: Efficient monitoring of tumor responsiveness to chemotherapy is essential to mitigate high mortality risks and cytotoxic effects of chemotherapeutics. However, there is no consensus on the most suitable diagnostic technique/parameters for assessing response to chemotherapy in malignant pleural mesothelioma (MPM). We compared the tumor responsiveness of MPM patients as assessed using modified RECIST (mRECIST) criteria and integrated 18F-FDG-PET/CT. METHODS: Histologically confirmed MPM patients (N=82) who were treated with three cycles of cisplatin and pemetrexed, or carboplatin and pemetrexed, were included. mRECIST and integrated 18F-FDG-PET/CT were used to evaluate MPM tumor response to chemotherapy. Metabolic non-responders were defined as those with a 25% or greater increase in SUVmax compared with the previous value. Time to progression (TTP) and overall survival (OS) were compared between metabolic-responders and non-responders. RESULTS: After three cycles of chemotherapy, 62(75.6%) of the patients were classified as having SD, 15 (18%) with partial remission (PR), and 5 (6%) with progressive disease (PD), based on mRECIST criteria. The cumulative median OS was 728.0days (95% confidence interval [CI]: 545.9-910.1) and cumulative median TTP was 365.0days (95% CI: 296.9-433.1). For the 82 patients, the disease control rate was 93.9%, whereas the metabolic response rate was only 71.9% (p<0.001). All PD and PR patients were found to be metabolic responders on 18F-FDG-PET/CT; however, among the 62mRECIST SD patients, 18 (29%) were classified as metabolic non-responders. The median TTP for metabolic responders was 13.7 months, while it was 10.0 months for non-responders(p<0.001). Metabolic responders had a trend toward longer OS, although the difference did not reach statistical significance (metabolic responders:33.9 months; non-responders: 21.6 months; p>0.05). CONCLUSION: Several mRECIST-confirmed SD MPM patients may be classified as metabolic non-responders on18F-FDGPET/CT. Metabolic response is significantly correlated with the median TTP, suggesting it should be included in the evaluation of the response to chemotherapy in MPM patients classified as mRECIST SD, to identify non-responders.

Usefulness of preoperative CT colonography for colon cancer.

BACKGROUND: Computed tomographic colonography (CTC) is reported to be feasible for screening of colorectal polyps; however, its efficacy in preoperative workup remains unknown. This study was done to define our CTC methodology and assess CTC's potential for preoperative examination in patients with colon cancer. METHODS: A total of 86 colon cancer patients underwent CTC prior to laparoscopic colectomy in our department from February 2014 to November 2015. The location of primary colon cancer determined by CTC was compared with that confirmed during the surgery. CTC was performed just after preoperative colonoscopy; for a small colon cancer, we performed clipping during colonoscopy to enhance CTC detectability. We classified wall deformities and compared them with the pathological T stage. RESULTS: CTC accurately located all 87 primary colon cancers prior to surgery. No patient experienced complications associated with CTC. The deformity classification correlated significantly with the pathological T stage (p < 0.001, Kruskal-Wallis nonparametric tests). CTC provided reconstructed images depicting the feeding artery of the primary colon cancer; feeding artery information obtained by CTC facilitated precise lymph node dissection. CONCLUSION: CTC appears to be a feasible and useful preoperative examination modality for colon cancer treatment.

Reducing CT radiation exposure with organ effective modulation: A retrospective clinical study.

OBJECTIVE: To evaluate the effect of Organ Effective Modulation (OEM) on objective and subjective image quality as well as the radiation dose needed for thoracoabdominal computed tomography (CT). METHOD: This retrospective study included 196 consecutive patients who were referred to our institution for enhanced thoracoabdominal CT on a specific scanner. Patients were divided into two groups: those for whom OEM was used and those for whom it was not used. For the non-OEM group, the tube current was controlled with an angular-longitudinal modulation technique. All CT examinations were performed with adaptive iterative dose reduction with 3D processing (AIDR-3D). The radiation dose was compared between the two groups. Objective image noise was measured in several regions at the thoracic and abdominal level. Subjective image quality was assessed by two radiologists for image noise, artifacts, sharpness, and overall diagnostic acceptability at the chest, abdomen, and pelvis. RESULTS: The CTDIvol was 8.3% lower in the OEM group and high-BMI patients tended to have higher dose reductions. Image noise was not significantly different at the thoracic level, except for the ventral air space, which showed more noise in the OEM group. At the abdominal level, the OEM group showed less noise in every region, only demonstrating a significant difference in the posterior segment of the right hepatic lobe. Subjective image quality assessment indicated more artifacts in the thoracic ventral air space in the OEM group, whereas all other items including the overall diagnostic acceptability showed no statistical differences between the two groups. CONCLUSION: OEM can reduce the radiation dose by approximately 8% without affecting the diagnostic acceptability of the image compared to angular-longitudinal modulation, especially in patients with a high BMI.

Double-Balloon-Assisted n-Butyl-2-Cyanoacrylate Embolization of Intrahepatic Arterioportal Shunt Prior to Chemoembolization of Hepatocellular Carcinoma.

A case of multiple hepatocellular carcinomas with a severe intrahepatic arterioportal shunt that was successfully embolized with n-butyl-2-cyanoacrylate with coaxial double-balloon occlusion prior to transcatheter arterial chemoembolization is presented. A proximal balloon positioned at the proper hepatic artery was used for flow control, and a coaxial microballoon, positioned in the closest of three arterial feeding branches to the arterioportal shunt, was used to control the delivery of n-butyl-2-cyanoacrylate. This coaxial double-balloon technique can prevent proximal embolization and distal migration of n-butyl-2-cyanoacrylate and enable precise control of the distribution of n-butyl-2-cyanoacrylate. It could also be applicable to n-butyl-2-cyanoacrylate embolization for other than intrahepatic arterioportal shunt.

CT findings of gastric and intestinal anisakiasis.

PURPOSE: To illustrate the CT findings of gastrointestinal anisakiasis. SUBJECTS AND METHODS: The Institutional Review Board approving this retrospective study waived the requirement for informed consent. Review of our emergency department's clinical records from September 2008 to January 2012 identified 41 consecutive patients who were diagnosed with gastrointestinal anisakiasis. 20 patients were diagnosed with gastric anisakiasis with endoscopically proven Anisakis larvae, and 21 patients were diagnosed with intestinal anisakiasis with positive test results for anti-anisakidae antibody and the presence of intestinal lesions on CT. Two radiologists retrospectively assessed the CT findings. RESULTS: The mean time delay from raw fish ingestion to symptom onset was 5.2 h (range 0.5-24 h) in gastric anisakiasis and 39 h (range 12-120 h) in intestinal anisakiasis. Gastric anisakiasis showed marked submucosal edema of the gastric wall (20/20 patients, 100%), increased attenuation of adjacent fat (19/20, 95%), and ascites (14/20, 70%) on CT. Intestinal anisakiasis showed marked submucosal edema of the intestine (21/21 patients, 100%) without showing complete intraluminal occlusion, ascites (21/21, 100%), increased attenuation of adjacent fat (19/21, 90%), and fluid collection in the distal segment of the constricted small intestine (13/21, 62%) on CT. CONCLUSION: Severe submucosal edema with ascites is a characteristic finding of gastrointestinal anisakiasis when compared with other forms of gastroenteritis. When CT shows the typical findings of gastrointestinal anisakiasis, radiologists may suggest the possibility of clinically undiagnosed anisakiasis, especially in intestinal anisakiasis as the diagnosis is sometimes difficult due to the long interval between food intake and symptom onset.

Free fatty acids inhibit protein tyrosine phosphatase 1B and activate Akt.

BACKGROUND/AIMS: Accumulating evidence has suggested that free fatty acids (FFAs) interact with protein kinases and protein phosphatases. The present study examined the effect of FFAs on protein phosphatases and Akt. METHODS: Activities of protein phosphatase 1 (PP1), protein phosphatase 2A (PP2A), and protein tyrosine phosphatase 1B (PTP1B) were assayed under the cell-free conditions. Phosphorylation of Akt was monitored in MSTO-211H human malignant pleural mesothelioma cells without and with knocking-down phosphatidylinositol 3 kinase (PI3K) or 3-phosphoinositide-dependent protein kinase-1 (PDK1). RESULTS: In the cell-free assay, unsaturated FFAs (uFFAs) such as oleic, linoleic and linolenic acid and saturated FFAs (sFFAs) such as stearic, palmitic, myristic, and behenic acid markedly reduced PTP1B activity, with the potential for uFFAs greater than that for sFFAs. All the investigated sFFAs inhibited PP2A activity, but otherwise no inhibition was obtained with uFFAs. Both uFFAs and sFFAs had no effect on PP1 activity. Oleic acid phosphorylated Akt both on Thr308 and Ser473, while stearic acid phosphorylated Akt on Thr308 alone. The effects of oleic and stearic acid on Akt phosphorylation were abrogated by the PI3K inhibitor wortmannin or the PDK1 inhibitor BX912 and also by knocking-down PI3K or PDK1. CONCLUSION: The results of the present study indicate that uFFAs and sFFAs could activate Akt through a pathway along a PI3K/PDK1/Akt axis in association with PTP1B inhibition.

Serum HMGB1 as a diagnostic marker for malignant peritoneal mesothelioma.

BACKGROUND: Diffuse malignant peritoneal mesothelioma (DMPM) is an aggressive malignant tumor of mesothelial origin that shows a limited response to cytoreductive surgery along with intraperitoneal chemotherapy. Therefore, early diagnosis of DMPM is very important. Some researchers have previously reported that high-mobility group box 1 (HMGB1) was correlated with pulmonary fibrosis. DMPM involves the malignant transformation of mesothelial cells, which originate from mesenchymal cells, similar to lung fibroblasts. Here, we investigated serum levels of HMGB1 in patients with MPM and compared them with those of a population that had been exposed to asbestos without developing MPM. STUDY: The serum concentrations of HMGB1 were measured in 13 DMPM patients and 45 individuals with benign asbestos-related diseases. RESULT: We demonstrated that the patients with DMPM had significantly higher serum levels of HMGB1 compared with the population who had been exposed to asbestos but did not develop DMPM. CONCLUSION: Our data suggest that serum HMGB1 concentration is a useful serum marker for DMPM.