Radiomics model versus 2017 revised international consensus guidelines for predicting malignant intraductal papillary mucinous neoplasms.

OBJECTIVES: To evaluate a CT-based radiomics model for identifying malignant pancreatic intraductal papillary mucinous neoplasms (IPMNs) and compare its performance with the 2017 international consensus guidelines (ICGs). MATERIALS AND METHODS: We retrospectively included 194 consecutive patients who underwent surgical resection of pancreatic IPMNs between January 2008 and December 2020. Surgical histopathology was the reference standard for diagnosing malignancy. Using radiomics features from preoperative contrast-enhanced CT, a radiomics model was built with the least absolute shrinkage and selection operator by a five-fold cross-validation. CT and MR images were independently reviewed based on the 2017 ICGs by two abdominal radiologists, and the performances of the 2017 ICGs and radiomics model were compared. The areas under the curve (AUCs) were compared using the DeLong method. RESULTS: A total of 194 patients with pancreatic IPMNs (benign, 83 [43%]; malignant, 111 [57%]) were chronologically divided into training (n = 141; age, 65 ± 8.6 years; 88 males) and validation sets (n = 53; age, 66 ± 9.7 years; 31 males). There was no statistically significant difference in the diagnostic performance of the 2017 ICGs between CT and MRI (AUC, 0.71 vs. 0.71; p = 0.93) with excellent intermodality agreement (k = 0.86). In the validation set, the CT radiomics model had higher AUC (0.85 vs. 0.71; p = 0.038), specificity (84.6% vs. 61.5%; p = 0.041), and positive predictive value (84.0% vs. 66.7%; p = 0.044) than the 2017 ICGs. CONCLUSION: The CT radiomics model exhibited better diagnostic performance than the 2017 ICGs in classifying malignant IPMNs. CLINICAL RELEVANCE STATEMENT: Compared with the radiologists' evaluation based on the 2017 international consensus guidelines, the CT radiomics model exhibited better diagnostic performance in classifying malignant intraductal papillary mucinous neoplasms. KEY POINTS: • There is a paucity of comparisons between the 2017 international consensus guidelines (ICGs) and radiomics models for malignant intraductal papillary mucinous neoplasms (IPMNs). • The CT radiomics model developed in this study exhibited better diagnostic performance than the 2017 ICGs in classifying malignant IPMNs. • The radiomics model may serve as a valuable complementary tool to the 2017 ICGs, potentially allowing a more quantitative assessment of IPMNs.

Effect of multimodal diagnostic approach using deep learning-based automated detection algorithm for active pulmonary tuberculosis.

In this study, we developed a model to predict culture test results for pulmonary tuberculosis (PTB) with a customized multimodal approach and evaluated its performance in different clinical settings. Moreover, we investigated potential performance improvements by combining this approach with deep learning-based automated detection algorithms (DLADs). This retrospective observational study enrolled patients over 18 years of age who consecutively visited the level 1 emergency department and underwent chest radiograph and sputum testing. The primary endpoint was positive sputum culture for PTB. We compared the performance of the diagnostic models by replacing radiologists' interpretations of chest radiographs with screening scores calculated through DLAD. The optimal diagnostic model had an area under the receiver operating characteristic curve of 0.924 (95% CI 0.871-0.976) and an area under precision recall curve of 0.403 (95% CI 0.195-0.580) while maintaining a specificity of 81.4% when sensitivity was fixed at 90%. Multicomponent models showed improved performance for detecting PTB when chest radiography interpretation was replaced by DLAD. Multicomponent diagnostic models with DLAD customized for different clinical settings are more practical than traditional methods for detecting patients with PTB. This novel diagnostic approach may help prevent the spread of PTB and optimize healthcare resource utilization in resource-limited clinical settings.

Coronary CTA for Acute Chest Pain in the Emergency Department: Comparison of 64-Detector-Row Single-Source and Third-Generation Dual-Source Scanners.

BACKGROUND. When coronary CTA is performed in the emergency department (ED), the use of a contemporary scanner with improved temporal resolution may eliminate the need to administer ß-blockers for heart rate (HR) control, thereby expediting workup. OBJECTIVE. The purpose of this study was to compare ED length of stay (LOS), image quality, frequency of nondiagnostic examinations, and other clinical outcomes between patients undergoing coronary CTA in the ED on a single-source CT (SSCT) scanner with HR control versus on a dual-source CT (DSCT) scanner without HR control. METHODS. This retrospective study included 509 patients (283 men, 226 women; mean age, 52.1 ± 15.1 [SD] years) at low to intermediate risk for acute coronary syndrome who underwent coronary CTA for acute chest pain during off-hours in a single ED from March 1, 2020, to April 25, 2022. A total of 205 patients initially underwent CTA using a 64-detector-row SSCT scanner with HR control (oral ß-blocker administration if HR was > 65 beats/min); after scanner replacement on April 26, 2021, 304 patients underwent CTA using a third-generation DSCT without HR control. Groups were compared in terms of ED LOS and CT completion time (defined as time from ordering CTA to completion of acquisition) using propensity score matching and additional endpoints including image quality and nondiagnostic examinations based on radiology reports. RESULTS. The DSCT group, compared with the SSCT group, showed no significant difference in median ED LOS (505 vs 457 minutes, respectively; p = .37) but showed shorter median CT completion time (95 vs 117 minutes, p < .001); on the basis of a mediation analysis, 89% of the reduction in CT completion time for DSCT was attributed to the absence of HR control. The DSCT group, compared with the SSCT group, showed higher frequency of examinations with good or excellent image quality (87.8% vs 60.0%, p < .001) and lower frequency of nondiagnostic examinations (1.6% vs 6.3%, p = .01) but showed no significant difference in frequencies of emergent cardiology consultation, invasive angiography, ED disposition, or coronary revascularization (all p > .05). No patient in either group experienced 30-day all-cause mortality or a major adverse cardiovascular event. CONCLUSION. The use of a DSCT scanner for coronary CTA can eliminate the need for ß-blocker administration for HR control while decreasing nondiagnostic examinations. CLINICAL IMPACT. A DSCT scanner can expedite clinical processes in the ED.

Hyperprogressive disease during PD-1 blockade in patients with advanced gastric cancer.

BACKGROUND: Investigations for programmed cell death-1 (PD-1) blockade-induced hyperprogressive disease (HPD) have not been stringently conducted in patients with advanced gastric cancer (AGC). We explored the occurrence of HPD and its clinical implications in patients with AGC and treated with PD-1 inhibitors. METHODS: We enrolled 169 patients with AGC and treated with either the PD-1 blockade (nivolumab or pembrolizumab; N = 112) or irinotecan monotherapy (N = 57) as a single agent. Tumour growth dynamics based on tumour growth kinetics and tumour growth rate (TGR) and time to treatment failure were analysed to define HPD. The incidence, clinical consequences and predictive markers of HPD were investigated. RESULTS: The optimal criteria for HPD were 4-fold increases in both tumour growth kinetics and TGR ratios and a 40% increase in TGR based on the analysis for patients treated with irinotecan. In total, 10.7% (12/112) of patients experienced HPD after PD-1 inhibitor treatment. Patients with HPD had both shorter progression-free survival (hazard ratio: 2.318; 95% confidence interval: 1.205-4.460) and overall survival (hazard ratio: 2.542; 95% confidence interval: 1.314-4.918) than patients with progressive disease without HPD, losing opportunities for subsequent systemic treatments. Although other variables including PD-L1 expression were not associated with the occurrence of HPD, hypoalbuminemia (<3.25 mg/dL) at baseline was significantly associated with the occurrence of HPD (P < 0.001) and inferior survival outcomes. CONCLUSIONS: HPD occurs in a proportion of patients with AGC and treated with PD-1 inhibitors. PD-1 inhibitor-induced HPD is associated with worse outcome, loss of eligibility for subsequent treatment and hypoalbuminemia, warranting further investigation.

MRI Radiomics Model Predicts Pathologic Complete Response of Rectal Cancer Following Chemoradiotherapy.

Background Preoperative assessment of pathologic complete response (pCR) in locally advanced rectal cancer (LARC) after neoadjuvant chemoradiotherapy (nCRT) is increasingly needed for organ preservation, but large-scale validation of an MRI radiomics model remains lacking. Purpose To evaluate radiomics models based on T2-weighted imaging and diffusion-weighted MRI for predicting pCR after nCRT in LARC and compare their performance with visual assessment by radiologists. Materials and Methods This retrospective study included patients with LARC (clinical stage T3 or higher, positive nodal status, or both) who underwent post-nCRT MRI and elective resection between January 2009 and December 2018. Surgical histopathologic analysis was the reference standard for pCR. Radiomic features were extracted from the volume of interest on T2-weighted images and apparent diffusion coefficient (ADC) maps from post-nCRT MRI to generate three models: T2 weighted, ADC, and both T2 weighted and ADC (merged). Radiomics signatures were generated using the least absolute shrinkage and selection operator with tenfold cross-validation. Three experienced radiologists independently rated tumor regression grades at MRI and compared these with the radiomics models' diagnostic outcomes. Areas under the curve (AUCs) of the radiomics models and pooled readers were compared by using the DeLong method. Results Among 898 patients, 189 (21%) achieved pCR. The patients were chronologically divided into training (n = 592; mean age ± standard deviation, 59 years ± 12; 388 men) and test (n = 306; mean age, 59 years ± 12; 190 men) sets. The radiomics signatures of the T2-weighted, ADC, and merged models demonstrated AUCs of 0.82, 0.79, and 0.82, respectively, with no evidence of a difference found between the T2-weighted and merged models (P = .49), while the ADC model performed worse than the merged model (P = .02). The T2-weighted model had higher classification performance (AUC, 0.82 vs 0.74 [P = .009]) and sensitivity (80.0% vs 15.6% [P < .001]), but lower specificity (68.4% vs 98.6% [P < .001]) than the pooled performance of the three radiologists. Conclusion An MRI-based radiomics model showed better classification performance than experienced radiologists for diagnosing pathologic complete response in patients with locally advanced rectal cancer after neoadjuvant chemoradiotherapy. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Taylor in this issue.

Development of a nutritional index to evaluate the effectiveness of total parenteral nutrition during the early postoperative period after pancreaticoduodenectomy.

BACKGROUND: Malnutrition leads to adverse effects on the short- and long-term prognosis in patients with periampullary diseases who underwent surgery. Nutritional risk indicators based on albumin and body weight have been developed to evaluate nutritional status and nutritional therapy efficacy, but no standard objective measurement has been devised to evaluate nutritional status during the early period after pancreaticoduodenectomy (PD). Therefore, this study aimed to assess the efficacy of total parenteral nutrition (TPN) during the early postoperative period after PD. METHODS: We analyzed 28 patients with a periampullary disease-common bile duct cancer, ampulla of Vater cancer, pancreatic head cancer, neuroendocrine tumor, chronic pancreatitis-who have undergone PD from Jan. 1, 2012 to Dec. 31, 2016. For all the patients, TPN was administered from postoperative day (POD) 1 at 25 Kcal/kg ideal body weight. Various nutritional indicators were measured such as Body mass index, nutritional risk index, protein, albumin, prealbumin, C-reactive protein. The volume of skeletal muscle area, muscle density, visceral and subcutaneous fat areas were assessed two times, preoperatively and on POD 7 by CT scan at the 3rd lumbar spine (L3) level. RESULTS: Average age of the 28 study subjects (18 males and 10 females) was 63.5±9.7 years. Although there is no difference in BMI between preoperative result and POD 7, protein, albumin, and prealbumin levels were significantly lower POD 7 the preoperative (P<0.001), but CRP was higher (P<0.001), and prealbumin and CRP levels were negatively correlated (R=-0.682, P<0.01). Muscle mass increased postoperatively (P=0.02), but the amount of visceral fat decreased (P=0.00). Based on CRP, and muscle density results, muscle, visceral and subcutaneous fat masses did not change after PD. CONCLUSIONS: In order to evaluate the nutritional status accurately after the hepato-biliary radical surgery, we suggest the muscle and fat mass measurement that can adjust the degree of inflammation during the early postoperative period.

Effect of deep learning-based assistive technology use on chest radiograph interpretation by emergency department physicians: a prospective interventional simulation-based study.

BACKGROUND: Interpretation of chest radiographs (CRs) by emergency department (ED) physicians is inferior to that by radiologists. Recent studies have investigated the effect of deep learning-based assistive technology on CR interpretation (DLCR), although its relevance to ED physicians remains unclear. This study aimed to investigate whether DLCR supports CR interpretation and the clinical decision-making of ED physicians. METHODS: We conducted a prospective interventional study using a web-based performance assessment system. Study participants were recruited through the official notice targeting board for certified emergency physicians and residents working at the present ED. Of the eight ED physicians who volunteered to participate in the study, seven ED physicians were included, while one participant declared withdrawal during performance assessment. Seven physicians' CR interpretations and clinical decision-making were assessed based on the clinical data from 388 patients, including detecting the target lesion with DLCR. Participant performance was evaluated by area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, and accuracy analyses; decision-making consistency was measured by kappa statistics. ED physicians with < 24 months of experience were defined as 'inexperienced'. RESULTS: Among the 388 simulated cases, 259 (66.8%) had CR abnormality. Their median value of abnormality score measured by DLCR was 59.3 (31.77, 76.25) compared to a score of 3.35 (1.57, 8.89) for cases of normal CR. There was a difference in performance between ED physicians working with and without DLCR (AUROC: 0.801, P < 0.001). The diagnostic sensitivity and accuracy of CR were higher for all ED physicians working with DLCR than for those working without it. The overall kappa value for decision-making consistency was 0.902 (95% confidence interval [CI] 0.884-0.920); concurrently, the kappa value for the experienced group was 0.956 (95% CI 0.934-0.979), and that for the inexperienced group was 0.862 (95% CI 0.835-0.889). CONCLUSIONS: This study presents preliminary evidence that ED physicians using DLCR in a clinical setting perform better at CR interpretation than their counterparts who do not use this technology. DLCR use influenced the clinical decision-making of inexperienced physicians more strongly than that of experienced physicians. These findings require prospective validation before DLCR can be recommended for use in routine clinical practice.

Gadoxetic acid-enhanced MRI of macrotrabecular-massive hepatocellular carcinoma and its prognostic implications.

BACKGROUND & AIMS: Despite the clinical and genetic significance of macrotrabecular-massive hepatocellular carcinoma (MTM-HCC), its characteristics on imaging have not been described. This study aimed to characterise MTM-HCC on gadoxetic acid-enhanced MRI and to evaluate the diagnostic accuracy and prognostic value of these imaging characteristics. METHODS: We enrolled 3 independent cohorts from 2 tertiary care centres. The 3 cohorts consisted of a total of 476 patients who underwent gadoxetic acid-enhanced MRI and surgical resection for treatment-naïve single HCCs. Independent review of histopathology and MRI by 2 reviewers was performed for each cohort, and inter-reader agreement was evaluated. Based on the result of MRI review in the training cohort (cohort 1), we developed 2 diagnostic criteria for MTM-HCC and evaluated their prognostic significance. The diagnostic performance and prognostic significance were validated in 2 validation cohorts (cohorts 2 and 3). RESULTS: We developed 2 diagnostic MRI criteria (MRIC) for MTM-HCC: MRIC-1, ≥20% arterial phase hypovascular component; MRIC-2, ≥50% hypovascular component and 2 or more ancillary findings (intratumoural artery, arterial phase peritumoural enhancement, and non-smooth tumour margin). MRIC-1 showed high sensitivity and negative predictive value (88% and 95% in the training cohort, and 88% and 97% in the pooled validation cohorts, respectively), whereas MRIC-2 demonstrated moderate sensitivity and high specificity (47% and 94% in the training cohort, and 46% and 96% in the pooled validation cohorts, respectively). MRIC-2 was an independent poor prognostic factor for overall survival in both training and pooled validation cohorts. CONCLUSIONS: Using gadoxetic acid-enhanced MRI findings, including an arterial phase hypovascular component, we could stratify the probability of MTM-HCC and non-invasively obtain prognostic information. LAY SUMMARY: Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is a histopathologic subtype of HCC characterised by aggressive biological behaviour and poor prognosis. We developed imaging criteria based on liver MRI that could be used for the non-invasive diagnosis of MTM-HCC. HCCs showing imaging findings of MTM-HCC were associated with poor outcomes after hepatic resection.

Human Organic Anion Transporting Polypeptide 1B3 Applied as an MRI-Based Reporter Gene.

OBJECTIVE: Recent innovations in biology are boosting gene and cell therapy, but monitoring the response to these treatments is difficult. The purpose of this study was to find an MRI-reporter gene that can be used to monitor gene or cell therapy and that can be delivered without a viral vector, as viral vector delivery methods can result in long-term complications. MATERIALS AND METHODS: CMV promoter-human organic anion transporting polypeptide 1B3 (CMV-hOATP1B3) cDNA or CMV-blank DNA (control) was transfected into HEK293 cells using Lipofectamine. OATP1B3 expression was confirmed by western blotting and confocal microscopy. In vitro cell phantoms were made using transfected HEK293 cells cultured in various concentrations of gadoxetic acid for 24 hours, and images of the phantoms were made with a 9.4T micro-MRI. In vivo xenograft tumors were made by implanting HEK293 cells transfected with CMV-hOATP1B3 (n = 4) or CMV-blank (n = 4) in 8-week-old male nude mice, and MRI was performed before and after intravenous injection of gadoxetic acid (1.2 µL/g). RESULTS: Western blot and confocal microscopy after immunofluorescence staining revealed that only CMV-hOATP1B3-transfected HEK293 cells produced abundant OATP1B3, which localized at the cell membrane. OATP1B3 expression levels remained high through the 25th subculture cycle, but decreased substantially by the 50th subculture cycle. MRI of cell phantoms showed that only the CMV-hOATP1B3-transfected cells produced a significant contrast enhancement effect. In vivo MRI of xenograft tumors revealed that only CMV-hOATP1B3-transfected HEK293 tumors demonstrated a T1 contrast effect, which lasted for at least 5 hours. CONCLUSION: The human endogenous OATP1B3 gene can be non-virally delivered into cells to induce transient OATP1B3 expression, leading to gadoxetic acid-mediated enhancement on MRI. These results indicate that hOATP1B3 can serve as an MRI-reporter gene while minimizing the risk of long-term complications.

The Modified Response Evaluation Criteria in Solid Tumors (RECIST) Yield a More Accurate Prognoses Than the RECIST 1.1 in Hepatocellular Carcinoma Treated with Transarterial Radioembolization.

Background/Aims: The Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and modified RECIST (mRECIST) criteria have been used to assess treatment responses for hepatocellular carcinoma (HCC) patients. We investigated which criteria provides better survival predictions in HCC patients treated with transarterial radioembolization (TARE). Methods: In total, 102 patients with unresectable intrahepatic HCC, who were treated with TARE between 2012 and 2017, were reviewed retrospectively. The treatment response after TARE was evaluated at 1, 3, and 6 months by the mRECIST and RECIST 1.1. Responders were defined as patients with complete or partial responses by each criterion. Results: The median age of 83 men and 19 women was 64.3 years. The median alpha-fetoprotein and des-gamma-carboxy prothrombin levels were 37.1 ng/mL and 1,780.0 mAU/mL, respectively. The median maximal tumor size was 8.3 cm, and multiple tumors were observed in 36 patients (35.3%). During the follow-up period (median, 20.7 months), 21 patients (20.6%) died, with a mean survival time of 55.5 months. The cumulative survival rate was 96.1% at 6 months and 89.3% at 12 months. Responders, defined by the mRECIST at 1, 3, and 6 months after TARE, showed better survival outcomes than nonresponders (hazard ratio [HR]=5.736, p=0.008 at 1 month; HR=3.145, p=0.022 at 3 months, and HR=2.887, p=0.061 at 6 months). The survival rates of responders and nonresponders defined by the RECIST 1.1 were similar (all p>0.05). Conclusions: Response evaluations that use the mRECIST provide more accurate prognoses than those that use the RECIST 1.1 in HCC patients treated with TARE.

Metal implants influence CT scan parameters leading to increased local radiation exposure: A proposal for correction techniques.

Metal implants not only deteriorate image quality, but also increase radiation exposure. The purpose of this study was to evaluate the effect of metal hip prosthesis on absorbed radiation dose and assess the efficacy of organ dose modulation (ODM) and metal artifact reduction (MAR) protocols on dose reduction. An anthropomorphic phantom was scanned with and without bilateral metal hip prostheses, and surface and deep level radiation doses were measured at the abdomen and pelvis. Finally, the absorbed radiation doses at pelvic and abdominal cavities in the reference, ODM, and two MAR scans (Gemstone spectral imaging, GE) were compared. The Mann Whitney-U test and Kruskal-Wallis test were performed to compare the volume CT dose index (CTDIvol) and mean absorbed radiation doses. Unilateral and bilateral metal hip prostheses increased CTDIVOL by 14.4% and 30.5%, respectively. MAR protocols decreased absorbed radiation doses in the pelvis. MAR showed the most significant dose reduction in the deep pelvic cavity followed by ODM. However, MAR protocols increased absorbed radiation doses in the upper abdomen. ODM significantly reduced absorbed radiation in the pelvis and abdomen. In conclusion, metal hip implants increased radiation doses in abdominopelvic CT scans. MAR and ODM techniques reduced absorbed radiation dose in abdominopelvic CT scans with metal hip prostheses.

Phase II trial of preoperative sequential chemotherapy followed by chemoradiotherapy for high-risk gastric cancer.

BACKGROUND AND PURPOSE: To evaluate the safety and efficacy of preoperative chemotherapy (CTx) followed by chemoradiotherapy (CCRT) for high-risk gastric cancer (GC). METHODS AND MATERIALS: The inclusion criteria were as follows: (1) Borrmann type 4; (2) large Borrmann type 3 (≥8 cm); (3) single bulky (≥3 cm × 1) or multiple lymph nodes (≥1.5 cm × 3). Patients received two 21-day courses of induction CTx of TS-1 (35 mg/m2, p.o, twice daily on days 1-14), docetaxel (30 mg/m2, i.v., days 1 and 8), and cisplatin (30 mg/m2, i.v., days 1 and 8) followed by CCRT (two courses of TS-1 and cisplatin in combination with 45 Gy radiation). RESULTS: Forty-two patients were enrolled between March 2014 and February 2016, and 39 of these completed sequential CTx and CCRT. Among the 33 patients who underwent R0 resection, the pathologic response rate was 39.4% [no residual carcinoma (n = 5, 15.2%), with 1-10% residual carcinoma (n = 8, 24.2%)]. Overall, 4 patients (12.1%) were pathologic stage 0, 7 (21.2%) were stage I, 10 (30.3%) were stage II, and 12 (36.4%) were stage III. The overall survival rate at 3 years was 77.9% for stages 0 and I, 66.8% for stages II-III, and 33.3% for unresectable cases (P = 0.001). Toxicity was mild to moderate with grade 4 neutropenia (n = 1) and neutropenic fever (n = 1) as the most prominent side-effects. CONCLUSIONS: Sequential CTx and CCRT prior to surgery are feasible and effective for high-risk GC. TRIAL REGISTRATION NUMBER: NCT02495493.

Multidisciplinary treatment for patients with stage IV gastric cancer: the role of conversion surgery following chemotherapy.

BACKGROUND: With advances in gastric cancer chemotherapy, conversion surgery has drawn attention as a new strategy to improve the outcome of stage IV disease. We investigated the efficacy of conversion surgery following chemotherapy for patients with stage IV gastric cancer. METHODS: We retrospectively reviewed clinico-pathologic variables and oncologic outcomes for 101 patients with stage IV gastric cancer who were treated with systemic chemotherapy followed by gastrectomy with intension of curative resection from January 2005 to December 2012. RESULTS: In terms of the best response from palliative chemotherapy, complete or partial response were observed in 65 patients (64.4%) in overall. Complete response of metastatic site were observed in 72 (71.3%) and 66 (65.3%) patients as best and pre-operative response, respectively. The overall complete macroscopic resection, rate was 56.4%. Eleven patients (10.9%) received combined metastasectomy. There was no postoperative surgery-related mortality for 1 month. The median overall survival time was 26.0 months. Multivariable analysis identified complete macroscopic resection, chemotherapy response (complete response/partial response) of metastatic sites, and change in CEA level as independent prognostic factors contributing to overall survival. CONCLUSIONS: Patients with stage IV gastric cancer who exhibit a good clinical response to chemotherapy might obtain greater survival benefit from gastrectomy following chemotherapy compared with patients who exhibit a poor response to chemotherapy. Prospective, randomized trials are required to determine the best strategy for combining initial chemotherapy with subsequent gastrectomy.

Marked Loss of Muscle, Visceral Fat, or Subcutaneous Fat After Gastrectomy Predicts Poor Survival in Advanced Gastric Cancer: Single-Center Study from the CLASSIC Trial.

BACKGROUND: There is increasing interest in the influence of body composition on oncological outcomes. We evaluated the role of skeletal muscle and fat among patients with gastric cancer (GC) who underwent gastrectomy with or without adjuvant chemotherapy, as well as those changes' associations with survival outcomes. METHODS: The present study evaluated 136 patients with GC who were enrolled in the CLASSIC Trial at Yonsei Cancer Center. Baseline body compositions including skeletal muscle area, Hounsfield units (HU), visceral fat area, and subcutaneous fat area were measured by preoperative computed tomography (CT). CT before and after the gastrectomy were used to determine the 6-month relative changes in body composition parameters. Continuous variables were dichotomized according to the best cutoff values by Contal and O'Quigley method. RESULTS: Seventy-three patients (53.7%) underwent surgery alone, and 63 patients (46.3%) underwent surgery followed by adjuvant chemotherapy. The baseline body composition parameters were not associated with disease-free survival (DFS) or overall survival (OS). Except for the HU, the marked loss of muscle, visceral fat, or subcutaneous fat significantly predicted shorter DFS and OS. Patients with a marked loss in at least one significant body composition parameter had significantly shorter DFS (hazard ratio 2.9, 95% confidence interval 1.7-4.8, P < 0.001) and OS (hazard ratio 2.9, 95% confidence interval 1.7-5.0, P < 0.001). CONCLUSIONS: Marked loss in body composition parameters significantly predicted shorter DFS and OS among patients with GC who underwent gastrectomy. Postoperative nutrition and active healthcare interventions could improve the prognosis of these GC patients.

Reproducibility of European Association for the Study of the Liver criteria and modified Response Evaluation Criteria in Solid Tumors in patients treated with sorafenib.

BACKGROUND & AIMS: The European Association for the Study of the Liver criteria and the modified Response Evaluation Criteria in Solid Tumors are used for assessing the treatment outcomes of hepatocellular carcinoma. We investigated the inter- and intra-observer reproducibility of the European Association for the Study of the Liver criteria and modified Response Evaluation Criteria in Solid Tumors in patients with advanced hepatocellular carcinoma treated with sorafenib. METHODS: A total of 99 patients with treatment-naive advanced hepatocellular carcinoma receiving sorafenib were included. The κ-values for the inter- and intra-observer agreement of the treatment response were calculated. RESULTS: Inter-observer agreement for baseline tumour number was excellent, as reflected by the high κ-value. The κ-statistics showed "excellent" concordance between the 2 sets of measurements by observer A regarding the overall responses using the European Association for the Study of the Liver criteria (κ = .948, agreement rate = 84.8%) and modified Response Evaluation Criteria in Solid Tumors (κ = .944, agreement rate = 83.8%; all P < .001). In addition, high κ-values indicated concordance between the first sets of measurements by observers A and B (κ = .991 by the European Association for the Study of the Liver criteria and .988 by modified Response Evaluation Criteria in Solid Tumors, all P < .001). When agreements in radiological overall responses between the 2 sets of measurements by observer B and between the second sets of measurements by observers A and B were calculated, similar results regarding high κ-values (>.8) were obtained. CONCLUSIONS: The reproducibility of the European Association for the Study of the Liver criteria and modified Response Evaluation Criteria in Solid Tumors in assessing treatment outcomes was high in patients with advanced hepatocellular carcinoma treated with sorafenib.

Increased hepatic FDG uptake on PET/CT in hepatic sinusoidal obstructive syndrome.

PURPOSE: Imaging features of sinusoidal obstruction syndrome (SOS), an increasingly common drawback of chemotherapy, were evaluated via 18F-fluorodeoxyglucose (FDG) positron emission tomography computed tomography (PET/CT). EXPERIMENTAL DESIGN: This retrospective study was approved by our Institutional Review Board, with a waiver of informed consent. FDG PET/CT studies of 35 patients (male, 24; female, 11; median age, 53.2 years) obtained between January, 2005 and December, 2012 were analyzed before and after systemic chemotherapy. Diagnosis of SOS was based on histologic (n=13) or gadoxetic acid-enhanced MRI (n=22) findings. On PET/CT images, ROIs drawn on non-tumorous liver generated mean standardized uptake value (SUVliver). Total lesion glycolysis of liver (TLGliver) was calculated as: SUVliver × CT-derived hepatic volume. Paired t-test was applied to compare changes before and after SOS. RESULTS: Mean (±standard error [SE]) values of hepatic volume (baseline, 1307.7±46.2 cm3; SOS, 1395.4±41.3 cm3; p=0.004), SUVliver (baseline, 2.08±0.06; SOS, 2.27±0.07; p=0.02), and TLGliver (baseline, 2697.5±114.5; SOS, 3170.2±134.2; p=0.001) significantly increased with development of SOS. In contrast, mean SUVaorta was unchanged (baseline, 1.53±0.04; SOS, 1.50±0.04; p=0.52). CONCLUSIONS: Hepatic FDG uptake on PET/CT intensified after onset of SOS and thus may be an inappropriate reference in this setting, potentially skewing chemotherapeutic responses gauged by lesion-to-liver SUV ratio.

Dynamic contrast-enhanced MRI coupled with a subtraction technique is useful for treatment response evaluation of malignant melanoma hepatic metastasis.

PURPOSE: To determine whether contrast-enhanced MRI including subtraction sequences can predict the treatment response of melanoma liver metastasis. RESULTS: High precontrast T1 signal intensity (SI) of melanoma lesions obscured detection of enhancement after contrast injection. It was impossible to determine whether or not enhancement occurred in the majority of lesions (85.4%, n = 35/41) without including the subtraction technique. Positive enhancement was identified in 14.6% (n = 6/41) of patients without subtraction images, but increased to 68.3% (n = 28/41) by including subtraction images. Follow-up studies determined lesion progression in 34.1% (n = 14/41) of patients. Positive enhancement on the subtraction image (odds ratio = 12.1, P = 0.048) and intermediate high T2 SI (odds ratio = 8.16, P = 0.040) were significantly associated with higher risk of lesion progression. MATERIALS AND METHODS: Patients who underwent MRI for melanoma liver metastases between January 2007 and February 2015 were enrolled. The study analyzed 41 liver metastases in 15 patients [11 male and four female; median age 56 years (range 21-81)] for size, lesion enhancement with and without subtraction images, and T2 SI. Follow-up imaging studies were used to determine treatment response. Data were analyzed with generalized estimating equations. CONCLUSIONS: MRI including the subtraction technique is useful for determining the treatment response of melanoma liver metastases. Lesion contrast enhancement and intermediate high T2 SI increased the risk of lesion progression.

Imaging Findings of Liposuction with an Emphasis on Postsurgical Complications.

Liposuction is one of the most frequently performed cosmetic surgeries worldwide for reshaping the body contour. Although liposuction is minimally invasive and relatively safe, it is a surgical procedure, and it carries the risk of major and minor complications. These complications vary from postoperative nausea to life-threatening events. Common complications include infection, abdominal wall injury, bowel herniation, bleeding, haematoma, seroma, and lymphoedema. Life-threatening complications such as necrotizing fasciitis, deep vein thrombosis, and pulmonary embolism have also been reported. In this paper, we provide a brief introduction to liposuction with the related anatomy and present computed tomography and ultrasonography findings of a wide spectrum of postoperative complications associated with liposuction.

Possible Contrast Media Reduction with Low keV Monoenergetic Images in the Detection of Focal Liver Lesions: A Dual-Energy CT Animal Study.

OBJECTIVE: To investigate the feasibility of dual-energy CT for contrast media (CM) reduction in the diagnosis of hypervascular and hypovascular focal liver lesions (FLL). SUBJECTS AND METHODS: The Institutional Animal Care and Use Committee approved this study. VX2 tumors were implanted in two different segments of the liver in 13 rabbits. After 2 weeks, two phase contrast enhanced CT scans including the arterial phase (AP) and portal-venous phase (PVP) were performed three times with 24-hour intervals with three different concentrations of iodine, 300 (I(300)), 150 (I(150)) and 75 mg I/mL (I(75)). The mean HU and standard deviation (SD) were measured in the liver, the hypervascular portion of the VX2 tumor which represented hypervascular tumors, and the central necrotic area of the VX2 tumor which represented hypovascular tumors in 140 kVp images with I(300) as a reference standard and in monoenergetic images (between 40 keV and 140 keV) with I(150) and I(75). The contrast-to-noise ratio (CNR) for FLLs and the ratio of the CNRs (CNR(ratio)) between monoenergetic image sets with I(150) and I(75), and the reference standard were calculated. RESULTS: For hypervascular lesions, the CNR(ratio) was not statistically different from 1.0 between 40 keV and 70 keV images with I(150), whereas the CNR(ratio) was significantly lower than 1.0 in all keV images with I(75). For hypovascular lesions, the CNR(ratio) was similar to or higher than 1.0 between 40 keV and 80 keV with I(150) and between 40 keV and 70 keV with I(75).. CONCLUSIONS: With dual-energy CT, the total amount of CM might be halved in the diagnosis of hypervascular FLLs and reduced to one-fourth in the diagnosis of hypovascular FLLs, while still preserving CNRs.

Clinical application of image-enhanced minimally invasive robotic surgery for gastric cancer: a prospective observational study.

BACKGROUND: This study was performed to validate the feasibility and role of image-guided robotic surgery using preoperative computed tomography (CT) images for the treatment of gastric cancer. METHODS: Twelve patients scheduled to undergo robotic gastrectomy for gastric cancer were registered. Vessels encountered during gastrectomy were reconstructed using 3D software and their anatomical variation was evaluated using preoperatively performed CT-angiography. The vascular information was transferred to a robot console using a multi-input display mode. Radiologic findings acquired from preoperative CT by the radiologist were compared with intraoperative findings of the surgeon. This study is registered with www.clinicaltrials.gov as NCT01338948. RESULTS: All 12 robotic gastrectomies were performed without any problems. All anatomical data acquired using 3D software were transferred successfully during surgery. Intraoperative vascular images depicted vasculatures around the stomach and could identify important vascular variations. During surgery, relevant vascular information led the surgeon to branch sites and facilitated lymphadenectomy around the vessels. Image-guidance during the operation provided a vascular map and enabled the surgeon to avoid accidental bleeding and damage to other organs by preventing vascular injuries. CONCLUSION: Image-guided robotic surgery for gastric cancer using preoperative CT-angiography reconstructed during operation by a surgically trained radiologist who could adjust the images by anticipating the operative procedure was feasible and improved the efficiency of surgery by eliminating the possibility of vascular injuries.