Imaging Staging Research Articles

Association between skeletal muscle morphometrics and overall survival among older adults with gastrointestinal cancers.

808 Background: Older adults with gastrointestinal (GI) cancers face a higher risk of treatment toxicities and adverse survival outcomes. However, the variability in these outcomes remains poorly understood. Age-related changes, including the progressive loss of skeletal muscle and gain in adipose tissue, contribute to this heterogeneity. Recent studies highlight an association between skeletal muscle gauge (SMG) and overall survival (OS) in older cancer patients, but its relevance among those with GI cancers is unclear. Methods: We included adults aged ≥ 60 years with newly diagnosed GI cancers, enrolled in the University of Alabama at Birmingham (UAB) Cancer and Aging Resilience Evaluation (CARE) registry between October 2017 and April 2024. Skeletal muscle index (SMI; skeletal muscle area in m²/height in cm) and skeletal muscle radiodensity (SMD; Hounsfield units) were derived from single-slice computed tomography (CT) staging scans at the third lumbar vertebra (L3) using validated methods. SMG was calculated as the product of SMI and SMD, reported in arbitrary units (AU). Participants were followed until death or the study cutoff date of July 10, 2024. Kaplan-Meier survival analysis was used to estimate OS by SMG status (low: < median; high: ≥ median). Cox proportional hazards models were employed to assess the relationship between SMG and OS, adjusting for age, sex, race/ethnicity, and cancer stage. Results: A total of 568 patients were included in the study, with a median age at diagnosis of 68 years (interquartile range, IQR: 64-74), 55% male, 73% non-Hispanic White, and 43% were diagnosed with Stage IV disease. Colorectal (33%) and pancreatic (27%) cancers were the most common diagnoses. The median SMG was 1,529 AU (IQR: 1,151–1,967). Over a median follow-up of 60 months, 367 patients (64%) died. Median OS was 19 months for those with low SMG and 26 months for those with high SMG (log-rank test, p < .05). After adjustment for confounders, SMG remained independently associated with OS (adjusted Hazard Ratio: 0.678 per IQR increase; 95% CI: 0.57– 0.807; p < .001), indicating that each IQR increase in SMG is associated with a decrease in all-cause mortality risk by 32.2%. Conclusions: Skeletal muscle gauge, an integrated measure of SMI and SMD, is significantly associated with improved survival among older adults with GI cancers. Further research is needed to determine whether SMG has a causal impact on survival in this population.

Association between visceral adipose tissue radiodensity and overall survival among older adults with colorectal carcinoma.

43 Background: Central obesity is a known risk factor for colorectal carcinoma (CRC); however, the association between visceral adipose tissue (VAT) and survival outcomes remains unclear. This study aims to investigate the relationship between VAT and overall survival (OS) among older adults with CRC. Methods: We analyzed data from the Cancer and Aging Resilience Evaluation registry, including adults aged ≥ 60 years with newly diagnosed CRC who were seen at the University of Alabama at Birmingham for initial consultation between October 2017 and April 2024. Using single-slice computed tomography staging scans, we calculated visceral adipose tissue radiodensity (VATD; in Hounsfield units, HU) at the third lumbar vertebra (L3) using validated methods. A lower VATD (more negative score) indicates higher visceral adipose tissue. Participants were followed until death or the study cutoff date of July 10, 2024. Kaplan-Meier survival analysis was performed to estimate OS for those with low VAT (VATD ≥ median VATD) versus high VAT (VATD < median VATD). Additionally, Cox proportional hazards models were utilized to evaluate the association between VATD and OS, adjusting for age at diagnosis, sex, race/ethnicity, skeletal muscle index (SMI), skeletal muscle density (SMD), and cancer stage. Results: A total of 190 patients were included, with a median age at diagnosis of 68 years (IQR: 64-75), 56% male, 72% non-Hispanic White, and 40% diagnosed with Stage IV disease. The median SMI and SMD were 42.06 (IQR: 33.81 - 49.52) cm 2 /m 2 and 38.68 HU (IQR: 31.38 - 44.89) respectively. The median VATD was -86.14 HU (IQR: -93.78 – -76.39). Over a median follow-up of 60 months, 96 patients (51%) died. Median OS was 27 months for patients with low VAT and 62 months for those with high VAT (log-rank test, p < .001). After adjusting for confounders, VATD remained independently associated with OS (adjusted Hazard Ratio: 1.41 per IQR decrease; 95% CI: 1.06 – 1.86; p ≤ .05), indicating that each IQR decrease in VATD scores (implying an increase in VAT) is associated with a 41% increased risk of all-cause mortality. Conclusions: Our findings demonstrate that increased visceral adipose tissue, indicated by more negative VATD scores, is significantly associated with poorer survival outcomes among older adults with CRC. These results underscore the importance of dietary and weight loss interventions to improve outcomes in this population.

Primary Results of NRG-RTOG1106/ECOG-ACRIN 6697: A Randomized Phase II Trial of Individualized Adaptive (chemo)Radiotherapy Using Midtreatment 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Stage III Non-Small Cell Lung Cancer.

NRG-RTOG0617 demonstrated a detrimental effect of uniform high-dose radiation in stage III non-small cell lung cancer. NRG-RTOG1106/ECOG-ACRIN6697 (ClinicalTrials.gov identifier: NCT01507428), a randomized phase II trial, studied whether midtreatment 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) can guide individualized/adaptive dose-intensified radiotherapy (RT) to improve and predict outcomes in patients with this disease. Patients fit for concurrent chemoradiation were randomly assigned (1:2) to standard (60 Gy/30 fractions) or FDG-PET-guided adaptive treatment, stratified by substage, primary tumor size, and histology. All patients had midtreatment FDG-PET/CT; adaptive arm patients had an individualized, intensified boost RT dose to residual metabolically active areas. The primary therapeutic end point was 2-year centrally reviewed freedom from local-regional progression (FFLP), defined as no progression in or near the planning target volume and/or regional nodes. FFLP was analyzed on a modified intent-to-treat population at a one-sided Z-test significance level of 0.15. The primary imaging end point was centrally reviewed change in SUVpeak from baseline to midtreatment; its association with FFLP was assessed using the two-sided Wald test on the basis of Cox regression. Of 138 patients enrolled, 127 were eligible. Adaptive-arm patients received a mean 71 Gy in 30 fractions, with mean lung dose 17.9 Gy. There was no significant difference in centrally reviewed 2-year FFLP (59.5% and 54.6% in standard and adaptive arms; P = .66). There were no significant differences in protocol-specified grade 3 toxicities, survival, or progression-free survival (P > .4). Median SUVpeak and metabolic tumor volume (MTV) in the adaptive arm decreased 49% and 54%, from pre-RT to mid-RT PET. However, ΔSUVpeak and ΔMTV were not associated with FFLP (hazard ratios, 0.997; P = .395 and .461). Midtreatment PET-adapted RT dose escalation as given in this study was safe and feasible but did not improve efficacy outcomes.

Solitary plasmacytoma: should new approaches in diagnosis and treatment be adopted?

Radiotherapy (RT) is the gold standard for solitary plasmacytomas (SP) with great local control. The influence of radiotherapy as well as factors on multiple myeloma (MM) progression is unknown. We present a retrospective study of 27 patients with SP (bone-SBP- and extramedullary-SEP-), treated since 1995 to 2021. We aim to analyze prognostic factors affecting local control and progression to MM in patients treated with radiotherapy (RT). Mean age was 57.3 years. 22 were SBP and 5 SEP. 13 patients were treated with definitive RT, and 14 with a combination of RT and systemic treatment and/or surgery. Local control was observed in 91.5% of cases. 28% experienced progression to MM. With a median follow up of 61.4 months [39.5, 121.6], 5-years MM-free-survival was 81 ± 8%; no individuals progressed further 50 months since diagnosis. Large tumor bulk (> 5 cm) and type (SBP 36% vs. SEP 0%) were associated with progression. Progression was not affected by doses greater than 46 Gy and/or surgery. An immunophenotype different from IgG kappa was predictive of less progression (p = 0.031) in Cox regression analysis adjusted for age, RT dose and tumor bulk > 5 cm. Patients with positron emission tomography-computed tomography (PET-CT) staging showed less MM progression, without statistical differences. RT achieves more than 90% of local control. The immunophenotype IgG kappa showed more risk of progression to MM. Initial staging with PET-CT seems to lead to a better identification of SP. The inclusion of bad prognosis patients in clinical trials would determine the role of adjuvant chemoimmunotherapy in SP treatment.

Role of Anterior Segment Optical Coherence Tomography in Staging and Evaluation of Treatment Response in Infectious Keratitis.

The aim of this study was to evaluate the role of anterior segment optical coherence tomography during follow-up of infectious keratitis and to assess response to treatment. This was a prospective, consecutive, observational clinical series of cases. Twenty-three eyes of 23 patients with clinically proven fungal keratitis were included in the study. The patients received medical treatment according to clinical diagnosis, and follow-up was performed weekly. Slit-lamp examination and photography, and anterior segment optical coherence tomography were performed at initial and follow-up visits until corneal healing occurred. The main outcome measures included infiltrate depth, width, and density; central corneal thickness; minimal corneal thickness; corneal thickness at the site of the lesion; and stromal thickness at the center of the lesion. Twenty-three eyes of 23 patients (17 men and 6 women), mean age 42.5 ± 19 (8-66) years, were clinically diagnosed with fungal keratitis. Localization was central in 14 cases and paracentral/peripheral in 9 cases. Healing time was 6 to 12 weeks. Minimal corneal thickness, corneal thickness at the site of lesion, and stromal thickness at the center of lesion, and also infiltrate width and depth changed significantly from the first visit to the healing stage at the last follow-up (0.009, 0.001, 0.007, 0.001, and <0.001, respectively). In cases of fungal keratitis, anterior segment optical coherence tomography can provide the clinician with a quantitative assessment of a number of corneal parameters that can be used to determine effectiveness of therapy and confirm complete healing of the lesions that cannot be achieved by clinical evaluation.

Effect of Dupilumab on Radiological Remission in Patients with Chronic Rhinosinusitis with Nasal Polyp: A One Step Forward Toward Clinical Remission.

While achieving complete radiological improvement in patients with nasal polyps is often observed following surgical resection, the impact of biologic therapy, specifically dupilumab, on polyp size is an area of great interest. The objective of this study was to assess the effect of dupilumab in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) by assessing nasal polyps using the computed tomography (CT) staging system, Lund-Mackay score (LMS). A two-year prospective cohort study was conducted on 29 patients diagnosed with CRSwNP and asthma and eligible for dupilumab as an add-on therapy. The study involved comprehensive assessments of patients before biologic initiation and after the study. These assessments included clinical, laboratory, and radiological evaluations. Dupilumab treatment reduces LMS across sinuses (p<0.001) and improves nasal obstruction (p=0.001). Blood eosinophil count (BEC) predicts persistent sinus obstruction, doubling the likelihood per unit increase (odds ratio: 1.67, p=0.02). BEC levels identify persistent nasal obstruction (AUC: 76%, p=0.04), with a cutoff point above 255.5 cells per microliter, revealing a sensitivity of 100% and a specificity of 42%. The probability of persistent nasal obstruction at the 20th month is 55%, regardless of prior nasal polyp surgery (p=0.41). Dupilumab led to significant radiological improvements in patients with CRSwNP, demonstrating a potential role of radiological remission, irrespective of prior nasal polyp surgery. Additionally, BEC levels may guide the likelihood of persistent nasal obstruction.

509. DOES SARCOPENIA AFFECT THE OUTCOME OF PATIENTS WITH ESOPHAGEAL CARCINOMA AFTER ESOPHAGECTOMY?

Abstract Background Sarcopenia is increasingly recognized as an independent predictor of clinical outcomes of cancer patients such as post-operative complications and prolonged hospital stays. Additionally, sarcopenia can also negatively impact overall survival because of reduced ability to tolerate treatments like neoadjuvant therapy and surgery. At particular risk among cancer patients is the esophageal cancer population because of tumor stenosis leading to dysphagia and impossibility of oral feeding in many patients. The purpose of the current study was to investigate the effect of preoperative sarcopenia on postoperative complications in patients undergoing esophagectomy for esophageal cancer. Methods This retrospective study includes all patients who underwent full-robotic abdominothoracic esophageal resection because of esophageal cancer at our institution between 06/2020 and 12/2022. The skeletal muscle index (SMI) was assessed using the preoperative computed tomographic staging scans by measuring the cross-sectional muscle area at the third lumbar vertebral level. Following cut off SMI values were used to define sarcopenia: men: 52,4 cm2/m2, women: 38,5 cm2/m2 according to Prado et al (Lancet Oncol, 2008). Recorded parameters included demographic data, neo-adjuvant treatment, histologic findings, postoperative course and overall- and disease-free survival. Results A total of 113 cases were included in this preliminary analysis. 97 patients (86%) were classified as having sarcopenia. Of these, 38 patients (40%) had a preoperatively or during esophageal resection implemented percutaneous endoscopic jejunostomy (PEJ) tube to ensure enteral nutrition. Despite age, groups were comparable regarding neoadjuvant treatment and histologic findings (mean age sarcopenic patients: 66y vs. 61y non-sarcopenic patients, p = 0.03). There was no difference in the incidence of occurrence of anastomotic leakage, pulmonary complications, need for re-operation, length of (ICU) stay and overall- and disease-free survival between sarcopenic and non-sarcopenic patients. Conclusion Incidence of sarcopenia is very high among esophageal cancer patients. In our study population, however, preoperative sarcopenia failed to predict complications or long-term outcome after esophagectomy for esophageal cancer. 40% of the sarcopenic patients received a PEJ. This relatively high proportion of implemented PEJ could have contributed to the observed comparable outcomes between sarcopenic and non-sarcopenic patients. This observation underlines the importance of prehabilitation and nutritional support for patients with preoperative sarcopenia.

Role of textural and radiomic analysis parameters in predicting histopathological parameters of the tumor in breast cancer patients.

Texture and radiomic analysis characterizes the tumor's phenotype and evaluates its microenvironment in quantitative terms. This study aims to investigate the role of textural and radiomic analysis parameters in predicting histopathological factors in breast cancer patients. Two hundred and twelve primary breast cancer patients underwent 18F-FDG PET/computed tomography for staging. The images were processed in a commercially available textural analysis software. ROI was drawn over the primary tumor with a 40% threshold and was processed further to derive textural and radiomic parameters. These parameters were then compared with histopathological factors of tumor. Receiver-operating characteristic analysis was performed with a P-value <0.05 for statistical significance. The significant parameters were subsequently utilized in various machine learning models to assess their predictive accuracy. A retrospective study of 212 primary breast cancer patients was done. Among all the significant parameters, SUVmin, SUVmean, SUVstd, SUVmax, discretized HISTO_Entropy, and gray level co-occurrence matrix_Contrast were found to be significantly associated with ductal carcinoma type. Four parameters (SUVmin, SUVmean, SUVstd, and SUVmax) were significant in differentiating the luminal subtypes of the tumor. Five parameters (SUVmin, SUVmean, SUVstd, SUVmax, and SUV kurtosis) were significant in predicting the grade of the tumor. These parameters showcased robust capabilities in predicting multiple histopathological parameters when tested using machine learning algorithms. Though textural analysis could not predict hormonal receptor status, lymphovascular invasion status, perineural invasion status, microcalcification status of tumor, and all the molecular subtypes of the tumor, it could predict the tumor's histologic type, triple-negative subtype, and score of the tumor noninvasively.

707: Expanding access to computed tomographic staging and three dimensional RT for cervical cancer

707: Expanding access to computed tomographic staging and three dimensional RT for cervical cancer

Pseudokidney Sign in Gastric Cancer.

Pseudokidney sign (PKS) is a characteristic sonographic finding of an abnormal mass with a reniform appearance, and a hyperechoic central region surrounded by a hypoechoic area. It has been seldom documented in gastric cancer. A 75-year-old male patient presented with a palpable abdominal resistance in the left upper abdominal quadrant and ultrasound evaluation revealed a well-vascularized mass presenting with PKS. Regional lymphadenopathy was also found, and the working diagnosis of gastric cancer was established. The suspected diagnosis was later verified endoscopically and on pathohistological examinations as gastric adenocarcinoma. Computed tomography staging also revealed distant metastases to the lungs, liver, and adrenal glands and abdominal lymphadenopathy. The PKS often indicates gastrointestinal pathology, and it may be seen in benign and malignant conditions due to gastrointestinal wall thickening. Therefore, additional diagnostic examinations are advised for a more definite diagnosis.

HSR24-148: Outcome of Positron Emission Tomography-Computed Tomography Staging in Breast Cancer Patients Having Neo-Adjuvant Systemic Therapy.

HSR24-148: Outcome of Positron Emission Tomography-Computed Tomography Staging in Breast Cancer Patients Having Neo-Adjuvant Systemic Therapy.

An unusual cause of biliary obstruction: a case report

Abdominal aortic aneurysms are considered as an unusual cause of extraductal biliary obstruction with less than 30 case studies found within the literature. This case report will discuss an 81-year-old female with an incidental initially asymptomatic finding of extrahepatic biliary obstruction and gallbladder distension secondary to an abdominal aortic aneurysm in routine computed tomography staging scan. Extraductal biliary obstructions can require alternative or additional interventions to that of treatment for intraductal obstruction. Subsequently, the aetiology of biliary obstruction is important for clinicians to consider and recognise, to allow for the implementation of appropriate and timely management.

Comparing fluorodeoxyglucose positron emission tomography with computed tomography in staging for nodal and distant metastasis in urothelial/bladder cancer.

We aim to assess the clinical value of 18F-fluorodeoxyglucose positron (18F-FDG-PET) scan in detecting nodal and distant metastasis compared with computed tomography (CT) scan in patients with urothelial carcinoma or bladder cancer, aiming to improve staging accuracy and thereby better prognosticate and determine therapy. A retrospective review of 75 patients with invasive bladder cancer (≥T1) who were staged with both CT and 18F-FDG-PET within an 8-week interval was performed for the period between 2015 and 2020. Seventy-two per cent (54/75) had formal pelvic lymph node (LN) dissection or biopsy of lesions suspicious for metastases. FDG-PET definitions for positive sites were assessed depending on SUV Max (nodes with SUVmax >4 at any size, SUV > 2 for lymph nodes >8mm, or any SUV if the lymph node was >10mm on axial images). For CT scanning, enlarged LN by RECIST 1.1 criteria (>10mm) as well as qualitative findings suggesting metastasis were considered positive. The analysis was based on the comparison of CT and 18F-FDG-PET findings to histopathology results from LN dissection or biopsies. Sensitivity, specificity, positive predictive values (PPV) and negative predictive value (NPV) of CT versus FDG-PET for detecting metastasis, in patients who underwent pelvic LN dissection or biopsy of lesions suspicious of metastases, were 46.6% (95% CI: 21%-70%) versus 60% (95% CI: 32%-84%), 100% (95% CI: 91%-100%) versus 83.78% (95% CI: 69%-94%), 100% (95% CI: 63%-100%) versus 60% (95% CI: 32%-84%), and 82.2% (95% CI: 68%-92%) versus 83.78% (95% CI: 69%-94%), respectively. 7/75 (9.3%) patients avoided cystectomy due to 18F-FDG-PET features of metastases that were not detected by CT. FDG-PET may be more sensitive than CT for metastases in the staging of bladder cancer, which resulted in significant avoidance of aggressive local management in cases with occult metastasis.

Expanding Access to Computed Tomographic Staging and Three-Dimensional Intensity Modulated Radiotherapy for Cervical Cancer in Ghana.

To build capacity for improved treatment of locally advanced cervical cancer in Ghana, including computed tomography (CT) staging and intensity modulated radiotherapy (IMRT). Patients with histologically confirmed cervical cancer were prospectively staged with abdominopelvic CT and ultrasound and offered the opportunity to have IMRT instead of conventional two-dimensional radiotherapy. The development of an efficient, high-quality, and safe IMRT program was facilitated by investment in new technology and comprehensive training of the interdisciplinary radiotherapy team in collaboration with a North American center of excellence. Of 215 patients with cervical cancer referred in 2022, 66% were able to afford CT scans and 26% were able to afford IMRT. Lymph node metastases were identified in 52% of patients by CT but in only 2% of patients by ultrasound. The use of CT resulted in 63% of patients being upstaged and changed treatment intent or radiation treatment volumes in 67% of patients. Patients who had IMRT experienced fewer acute side effects and were more likely to complete treatment as planned. It is feasible to provide state-of the-art cancer treatment with CT staging and IMRT to patients with cervical cancer in low-resource settings and achieve meaningful improvements in outcomes. It requires a broad commitment by program leadership to invest in technology and staff training. Major challenges include balancing improved clinical care with reduced patient throughput when radiation treatment capacity is constrained, and with the additional cost in the absence of universal health coverage.

Multimodality Appearances of Marginal Zone Lymphoma Masquerading as Cryptogenic Organizing Pneumonia-serial Chest Radiograph and High-resolution Computed Tomography Appearances: (18F) Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Staging Utility.

Marginal zone lymphoma (MZL) is a group of low-grade, indolent, non-Hodgkin lymphomas rarely manifesting in the lungs. A 46-year-old man presenting with shortness of breath and cough was investigated and treated over 10 months for an atypical pattern of lung disease in keeping with cryptogenic organizing pneumonia (COP). Initial lung biopsies were nondiagnostic - repeat sampling eventually showed MZL. Staging whole-body (18F) fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) demonstrated multisystem stage IV disease with intensely avid widespread pulmonary changes resembling COP. The case elegantly illustrates that pulmonary MZL can present insidiously masquerading as COP and shows the value of (18F) FDG PET/CT to stage extranodal MZL.

Increased serum cystatin C levels in patients with idiopathic epiretinal membrane

ABSTRACT Clinical relevance Increased serum cystatin C may play a role in the pathogenesis of idiopathic epiretinal membrane (IERM). Physicians should be aware of this relationship and should refer patients to the ophthalmology clinic for screening. Background To evaluate the serum cystatin C level in patients with IERM, and its associations with visual acuity. Methods Sixty-eight patients with IERM and sixty-nine controls were enrolled in this cross-sectional study. Based on the results of optical coherence tomography, patients with IERM were divided into four stages (I, II, III and IV). Serum cystatin C was measured in all participants. Serum cystatin C levels were compared between the control group and IERM group and between the IERM group with different optical coherence tomography stages. Multiple linear regression was used to evaluate the relationship between serum cystatin C and IERM stages and best corrected visual acuity. Results Serum cystatin C level was higher in the IERM group than in the control group (P < 0.001). There were statistically significant differences in serum cystatin C among different stages of IERM (P I vs II = 0.011, P I vs IV < 0.001 and P III vs IV = 0.040, respectively). There were significant differences in best corrected visual acuity among different stages of IERM (P I vs III = 0.018, P I vs IV < 0.001, P II vs IV < 0.001 and PIII vs IV < 0.001, respectively). Regression analysis showed a positive correlation between serum cystatin C and best corrected visual acuity (t = 2.238 P = 0.029). The cut-off value of receiver operation characteristic curve of serum cystatin C for IERM was 0.775. Conclusion This study revealed that serum cystatin C may be involved in the pathogenesis of IERM and can predict its occurrence. Elevated serum cystatin C appears to be associated with the severity of the disease and relatively poor vision acuity in IERM patients.

Using of 18 fluorine labeled prostatic specific membrane antigen positron emission tomography-computed tomography in staging of prostatic cancer in correlation with prostate specific antigen level

Using of 18 fluorine labeled prostatic specific membrane antigen positron emission tomography-computed tomography in staging of prostatic cancer in correlation with prostate specific antigen level

Reduced volume of diabetic pancreatic islets in rodents detected by synchrotron X-ray phase-contrast microtomography and deep learning network

The pancreatic islet is a highly structured micro-organ that produces insulin in response to rising blood glucose. Here we develop a label-free and automatic imaging approach to visualize the islets in situ in diabetic rodents by the synchrotron radiation X-ray phase-contrast microtomography (SRμCT) at the ID17 station of the European Synchrotron Radiation Facility. The large-size images (3.2mm×15.97mm) were acquired in the pancreas in STZ-treated mice and diabetic GK rats. Each pancreas was dissected by 3000 reconstructed images. The image datasets were further analysed by a self-developed deep learning method, AA-Net. All islets in the pancreas were segmented and visualized by the three-dimension (3D) reconstruction. After quantifying the volumes of the islets, we found that the number of larger islets (=>1500 μm3) was reduced by 2-fold (wt 1004±94 vs GK 419±122, P<0.001) in chronically developed diabetic GK rat, while in STZ-treated diabetic mouse the large islets were decreased by half (189±33 vs 90±29, P<0.001) compared to the untreated mice. Our study provides a label-free tool for detecting and quantifying pancreatic islets in situ. It implies the possibility of monitoring the state of pancreatic islets in vivo diabetes without labelling.

The predictive potential of contrast-enhanced computed tomography based radiomics in the preoperative staging of cT4 gastric cancer.

The accuracy of preoperative staging is crucial for cT4 stage gastric cancer patients. The aim of this study was to develop the radiomics model and evaluate its predictive potential for differentiating preoperative cT4 stage gastric cancer patients into pT4b and no-pT4b patients. A multicenter retrospective analysis of 704 gastric cancer patients with preoperative contrast-enhanced computed tomography (CE-CT) staging cT4 between January 2008 and December 2021. These patients were divided into the training cohort (478 patients, the Affiliated Hospital of Qingdao University) and validation cohort (226 patients, the Weihai Wendeng District People's Hospital). According to the pathological stage of the tumors, the patients were divided into pT4b or no-pT4b stage. In the training cohort, the clinical and radiomics features were analyzed to construct the clinical model, tri-phase radiomics signatures and nomogram. Two kinds of methods were employed to achieve dimensionality reduction: (I) the least absolute shrinkage and selection operator (LASSO); and (II) the minimum redundancy maximum relevance (mRMR) algorithms. We utilized Logistic regression, support vector machine (SVM), Decision tree and Adaptive boosted tree (AdaBoost) algorithms as the machine learning classifiers. The nomogram was constructed on the clinical characteristics and the Rad-score. The performance of the models was evaluated by receiver operating characteristic (ROC) area under the curve (AUC), Decision Curve Analysis (DCA) curve and calibration curve. The 345 pT4b and 359 no-pT4b stage patients were included in this study. In the validation cohort, the AUC of the clinical model was 0.793 (95% CI: 0.732-0.855). The tri-phase radiomics features combined with the SVM algorithm was the best radiomics signature with an AUC of 0.862 (95% CI: 0.812-0.912). The nomogram was the best predictive model of all with an AUC of 0.893 (95% CI: 0.834-0.927). In the training and validation cohorts, the calibration curves and DCA curves of the nomogram showed satisfactory result. CE-CT-based radiomics nomogram offers good accuracy and stability in differentiating preoperative cT4 stage gastric cancer patients into pT4b and non-pT4b stages, which has a great clinical relevance for selecting the course of treatment for cT4 stage gastric cancer patients.

Microcomputed tomography staging of bone histolysis in the regenerating mouse digit.

Humans and mice have the ability to regenerate the distal digit tip, the terminal phalanx (P3) in response to amputation. What distinguishes P3 regeneration from regenerative failure is formation of the blastema, a proliferative structure that undergoes morphogenesis to regenerate the amputated tissues. P3 regeneration is characterised by the phases of inflammation, tissue histolysis and expansive bone degradation with simultaneous blastema formation, wound closure and finally blastemal differentiation to restore the amputated structures. While each regenerating digit faithfully progresses through all phases of regeneration, phase progression has traditionally been delineated by time, that is, days postamputation (DPA), yet there is widespread variability in the timing of the individual phases. To diminish variability between digits during tissue histolysis and blastema formation, we have established an in-vivo method using microcomputed tomography (micro CT) scanning to identify five distinct stages of the early regeneration response based on anatomical changes of the digit stump. We report that categorising the initial phases of digit regeneration by stage rather than time greatly diminishes the variability between digits with respect to changes in bone volume and length. Also, stages correlate with the levels of cell proliferation, osteoclast recruitment and osteoprogenitor cell recruitment. Importantly, micro CT staging provides a means to estimate open versus closed digit wounds. We demonstrate two spatially distinct and stage specific bone repair/regeneration responses that occur during P3 regeneration. Collectively, these studies showcase the utility of micro CT imaging to infer the composition of radiolucent soft tissues during P3 blastema formation. Specifically, the staging system identifies the onset of cell proliferation, osteoclastogenesis, osteoprogenitor recruitment, the spatial initiation of de novo bone formation and epidermal closure.