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Background: Pretreatment differentiation between glioblastoma and metastasis is a frequently encountered dilemma in neurosurgical practice. Distinction is required for precise planning of resection or radiotherapy, and also for defining further diagnostic procedures. Morphology and spectroscopy imaging features are not specific and frequently overlap. This limitation of magnetic resonance imaging and magnetic resonance spectroscopy was the reason to initiate this study. The aim of the present study was to determine whether the dataset of diffusion tensor imaging metrics contains information which may be used for the distinction between primary and secondary intra-axial neoplasms. Methods: Two diffusion tensor imaging parameters were measured in 81 patients with an expansive, ring-enhancing, intra-axial lesion on standard magnetic resonance imaging (1.5 T system). All tumors were histologically verified glioblastoma or secondary deposit. For qualitative analysis, two regions of interest were defined: intratumoral and immediate peritumoral region (locations 1 and 2, respectively). Fractional anisotropy and mean difusivity values of both groups were compared. Additional test was performed to determine if there was a significant difference in mean values between two locations. Results: A statistically significant difference was found in fractional anisotropy values among two locations, with decreasing values in the direction of neoplastic infiltration, although such difference was not observed in fractional anisotropy values in the group with secondary tumors. Mean difusivity values did not appear helpful in differentiation between these two entities. In both groups there was no significant difference in mean difusivity values, neither in intratumoral nor in peritumoral location. Conclusion: The results of our study justify associating the diffusion tensor imaging technique to conventional morphologic magnetic resonance imaging as an additional diagnostic tool for the distinction between primary and secondary intra-axial lesions. Quantitative analysis of diffusion tensor imaging metric, in particular measurement of fractional anisotropy in peritumoral edema facilitates accurate diagnosis.

Background: Double reading of screening mammograms is associated with a higher rate of screen-detected cancer than single reading, but different strategies exist regarding reader pairing and blinding. Knowledge about these aspects is important when considering strategies for future use of artificial intelligence in mammographic screening. Purpose: To investigate screening outcome, histopathological tumor characteristics, and mammographic features stratified by the first and the second reader in a population based screening program for breast cancer. Material and Methods: The study sample consisted of data from 3,499,048 screening examinations from 834,691 women performed during 1996–2018 in BreastScreen Norway. All examinations were interpreted independently by two radiologists, 272 in total. We analyzed interpretation score, recall, and cancer detection, as well as histopathological tumor characteristics and mammographic features of the cancers, stratified by the first and second readers. Results: For Reader 1, the rate of positive interpretations was 4.8%, recall 2.3%, and cancer detection 0.5%. The corresponding percentages for Reader 2 were 4.9%, 2.5%, and 0.5% (P < 0.05 compared with Reader 1). No statistical difference was observed for histopathological tumor characteristics or mammographic features when stratified by Readers 1 and 2. Recall and cancer detection were statistically higher and histopathological tumor characteristics less favorable for cases detected after concordant positive compared with discordant interpretations. Conclusion: Despite reaching statistical significance, mainly due to the large study sample, we consider the differences in interpretation scores, recall, and cancer detection between the first and second readers to be clinically negligible. For practical and clinical purposes, double reading in BreastScreen Norway is independent. [ABSTRACT FROM AUTHOR]

Background: Cryoablation is a promising minimally invasive, nephron-sparing treatment of small renal carcinoma (RCC) in co-morbid patients. Purpose: To assess the safety, efficacy, and cancer-specific outcomes of computed tomography (CT)-guided cryoablation of stage T1 (RCC). Material and Methods: A retrospective evaluation of 122 consecutive patients with 128 tumors treated with cryoablation during 2016–2017. All patients had biopsy-verified T1 RCC. Results: Median age was 69 years (IQR=59–76); 69% were male. Median tumor size was 26 mm (± 20–33); 9% were stage T1b. Mean follow-up time was 36.3±12.0 months. In total, 14 (11%) procedures led to complications, of which 4 (3%) were intraoperative, 5 (4%) appeared ≤30 days and 5 (4%) >30 days after treatment. Major complications arose after 4 (3%) procedures. Statistically significant associations were found between major complications and stage T1b (P = 0.039), RENAL score (P = 0.010), and number of needles used in cryoablation (P = 0.004). Residual tumor was detected after 4 (3%) procedures and 5 (4%) tumors had local tumor progression. Of 122 patients, 3 (2%) advanced to metastatic disease. Significant statistical associations were found between local tumor progression and T1b stage tumors and number of needles used in cryoablation (P = 0.05 and P = 0.004, respectively). For patients with T1a tumors, the one- and three-year disease-free survival was 98% and 95%, respectively, and for T1b 100% after one year and 75% after three years. Conclusions: This study showed that cryoablation is a safe and effective treatment of stage T1 RCC and suggests that in selecting candidates for cryoablation of RCC, the tumor characteristics are more critical than patients' baseline health status. [ABSTRACT FROM AUTHOR]

Background: The diagnostic performance of magnetic resonance imaging (MRI) modalities and/or endoscopy for assessing complete response in rectal cancer after neoadjuvant chemoradiotherapy (nCRT) is unclear. Purpose: To summarize existing evidence on the diagnostic performance of diffusion-weighted MRI, perfusion-weighted MRI, T2-weighted MR tumor regression grade, and/or endoscopy for assessing complete tumor response after nCRT. Material and Methods: MEDLINE and Embase databases were searched. The PRISMA guidelines were followed. Sensitivity, specificity, negative predictive, and positive predictive values were retrieved from included studies. Results: In total, 81 studies were eligible for inclusion. Evidence suggests that combined use of MRI and endoscopy tends to improve the diagnostic performance compared to single imaging modality. The positive predictive value of a complete response varies substantially between studies. There is considerable heterogeneity between studies. Conclusion: Combined re-staging tends to improve diagnostic performance compared to single imaging modality, but the vast majority of studies fail to offer true clinical value due to the study heterogeneity. [ABSTRACT FROM AUTHOR]

(1) Background: For the peripheral zone of the prostate, diffusion weighted imaging (DWI) is the most important MRI technique; however, a high b-value image (hbDWI) must always be evaluated in conjunction with an apparent diffusion coefficient (ADC) map. We aimed to unify the important contrast features of both a hbDWI and ADC in one single image, termed multichannel computed diffusion images (mcDI), and evaluate the values of these images in a retrospective clinical study; (2) Methods: Based on the 2D histograms of hbDWI and ADC images of 70 patients with histologically proven prostate cancer (PCa) in the peripheral zone, an algorithm was designed to generate the mcDI. Then, three radiologists evaluated the data of 56 other patients twice in three settings (T2w images +): (1) hbDWI and ADC; (2) mcDI; and (3) mcDI, hbDWI, and ADC. The sensitivity, specificity, and inter-reader variability were evaluated; (3) Results: The overall sensitivity/specificity were 0.91/0.78 (hbDWI + ADC), 0.85/0.88 (mcDI), and 0.97/0.88 (mcDI + hbDWI + ADC). The kappa-values for the inter-reader variability were 0.732 (hbDWI + ADC), 0.800 (mcDI), and 0.853 (mcDI + hbDWI + ADC). (4) Conclusions: By using mcDI, the specificity of the MRI detection of PCa was increased at the expense of the sensitivity. By combining the conventional diffusion data with the mcDI data, both the sensitivity and specificity were improved. [ABSTRACT FROM AUTHOR]

Background: Radiation-associated angiosarcoma of the breast (RAASB) is a serious late consequence caused by breast cancer treatment. Initial symptoms are often inconspicuous, thus contributing to diagnostic delay. Most previous studies of the diagnostic aspects of RAASB are case reports. Purpose: To perform a complete review of the imaging findings and biopsy methods in a nationwide RAASB cohort. Material and Methods: RAASB patients were identified from a national cancer registry and additional patients were included from our hospital. All available information from imaging (mammogram [MGR], ultrasound [US], magnetic resonance imaging [MRI], and computed tomography [CT]) and biopsies was reviewed. The sensitivity of imaging and biopsy methods for detection of RAASB was calculated. Results: Fifty-eight patients with RAASB were found. Fourteen MGR, 30 US, 24 MRI, and 25 CT studies were available for evaluation. The sensitivity of MGR, US, MRI, and CT for detection of RAASB was 43%, 50%, 92%, and 84%, respectively. Superior sensitivity was demonstrated for punch biopsy (84%) and incisional biopsy (93%) compared to fine-needle aspiration cytology (0%) and core needle biopsy (18%). Conclusion: MRI and CT have comparable sensitivity for detection of RAASB, while MGR and US are unreliable. However, negative findings in MRI or CT must be interpreted with caution. Punch biopsy and incisional biopsy are the preferred biopsy methods. [ABSTRACT FROM AUTHOR]

Background: Magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (TULSA) is an emerging method for treatment of localized prostate cancer (PCa). TULSA-related subacute MRI findings have not been previously characterized. Purpose: To evaluate acute and subacute MRI findings after TULSA treatment in a treat-and-resect setting. Material and Methods: Six men with newly diagnosed MRI-visible and biopsy-concordant clinically significant PCa were enrolled and completed the study. Eight lesions classified as PI-RADS 3–5 were focally ablated using TULSA. One- and three-week follow-up MRI scans were performed between TULSA and robot-assisted laparoscopic prostatectomy. Results: TULSA-related hemorrhage was detected as a subtle T1 hyperintensity and more apparent T2 hypointensity in the MRI. Both prostate volume and non-perfused volume (NPV) markedly increased after TULSA at one week and three weeks after treatment, respectively. Lesion apparent diffusion coefficient values increased one week after treatment and decreased nearing the baseline values at the three-week MRI follow-up. Conclusion: The optimal timing of MRI follow-up seems to be at the earliest at three weeks after treatment, when the post-procedural edema has decreased and the NPV has matured. Diffusion-weighted imaging has little or no added diagnostic value in the subacute setting. [ABSTRACT FROM AUTHOR]

Background: Early prediction of response to concurrent chemoradiotherapy (cCRT) could aid to further optimize treatment regimens for locally advanced cervical cancer (LACC) in the future. Purpose: To explore whether quantitative parameters from baseline (pre-therapy) magnetic resonance imaging (MRI) and FDG-PET/computed tomography (CT) have potential as predictors of early response to cCRT. Material and Methods: Forty-six patients with LACC undergoing cCRT after staging with FDG-PET/CT and MRI were retrospectively analyzed. Primary tumor volumes were delineated on FDG-PET/CT, T2-weighted (T2W)-MRI and diffusion-weighted MRI (DWI) to extract the following quantitative parameters: T2W volume; T2W signalmean; DWI volume; ADCmean; ADCSD; MTV42%; and SUVmax. Outcome was the early treatment response, defined as the residual tumor volume on MRI 3–4 weeks after start of external beam radiotherapy with chemotherapy (before the start of brachytherapy): patients with a residual tumor volume <10 cm3 were classified as early responders. Imaging parameters were analyzed together with FIGO stage to assess their performance to predict early response, using multivariable logistic regression analysis with bi-directional variable selection. Leave-one-out cross-validation with bootstrapping was used to simulate performance in a new, independent dataset. Results: T2W volume (OR 0.94, P = 0.003) and SUVmax (OR 1.15, P = 0.18) were identified as independent predictors in multivariable analysis, rendering a model with an AUC of 0.82 in the original dataset, and AUC of 0.68 (95% CI 0.41–0.81) from cross-validation. Conclusion: Although the predictive performance achieved in this small exploratory dataset was limited, these preliminary data suggest that parameters from baseline MRI and FDG-PET/CT (in particular pre-therapy tumor volume) may contribute to prediction of early response to cCRT in cervical cancer. [ABSTRACT FROM AUTHOR]

Background: Background parenchymal enhancement (BPE) of normal tissue at breast magnetic resonance imaging is suggested to be an independent risk factor for breast cancer. Its association with established risk factors for breast cancer is not fully investigated.Purpose: To study the association between BPE and risk factors for breast cancer in a healthy, non-high-risk screening population.Material and Methods: We measured BPE and mammographic density and used data from self-reported questionnaires in 214 healthy women aged 43-74 years. We estimated odds ratios for the univariable association between BPE and risk factors. We then fitted an adjusted model using logistic regression to evaluate associations between BPE (high vs. low) and risk factors, including mammographic breast density.Results: The majority of women had low BPE (84%). In a multivariable model, we found statistically significant associations between BPE and age (P = 0.002) and BMI (P = 0.03). We did find a significant association between systemic progesterone medication and BPE, but due to small numbers, the results should be interpreted with caution. The adjusted odds ratio for high BPE was 3.1 among women with density D (compared to B) and 2.1 for density C (compared to B). However, the association between high BPE and density was not statistically significant. We did not find statistically significant associations with any other risk factors.Conclusion: Our study confirmed the known association of BPE with age and BMI. Although our results show a higher likelihood for high BPE with increasing levels of mammographic density, the association was not statistically significant. [ABSTRACT FROM AUTHOR]

Background: Genetic factors are important in determining breast density, and heritable factors account for 60% of the variation. Certain single nucleotide polymorphisms (SNPs) are associated with density and risk of breast cancer but the association with prognosis is not clear.Purpose: To investigate associations between selected SNPs and breast cancer survival in the Malmö Diet and Cancer Study (MDCS).Material and Methods: A total of 724 unrelated women with breast cancer and registered radiological and pathological data were identified in MDCS 1991-2007, with genotyping available for 672 women. Associations among 15 SNPs, density, and breast cancer-specific survival were analyzed using logistic/Cox regression, adjusted for factors affecting density and survival. Variants significantly associated with either density or survival were validated in a large independent breast cancer cohort (LIBRO-1).Results: Minor homozygotes of SNPs rs9383589, CCDC170 and rs6557161, ESR1 were associated with high breast density (adjusted odds ratio [AOR] 8.97, 95% confidence interval [CI] 1.35-59.57; AOR 2.08, 95% CI 1.19-3.65, respectively) and poorer breast cancer survival (adjusted hazard ratio [HRadj] 6.46, 95% CI 1.95-21.39; HRadj 2.30, 95% CI 1.33-3.96, respectively) compared to major homozygotes. For SNP rs3757318, ESR1, minor homozygotes (HRadj 7.46, 95% CI 2.28-24.45) were associated with poorer survival. We confirmed that rs6557161, ESR1 was significantly associated with both density and survival in the LIBRO-1 study.Conclusion: These findings support a shared genetic basis for density and breast cancer survival. The SNP significantly associated with both density and survival in both cohorts may be of interest in future research investigating polygenic risk scores for breast cancer risk and screening stratification purposes. [ABSTRACT FROM AUTHOR]

Chilaiditi syndrome, jejunal diverticulosis, and multiple primary malignant neoplasms (MPMN) are all relatively rare entities. In this study, clear cell renal cell carcinoma together with adenocarcinoma arising in the rectum were confirmed in an 82-year-old patient. Jejunal diverticulosis and Meckel diverticulitis were detected intraoperatively. Following radiotherapy with 25 Gy delivered in 5 fractions over 1 week, the patient underwent partial nephrectomy as well as abdominoperineal rectal resection and cholecystectomy due to cholelithiasis. The immediate postoperative period was uneventful, but the patient died of myocardial infarction on postoperative day 4. Malignancy may accompany Chilaiditi syndrome. In the presence of MPMN, appropriate treatment must be chosen individually on a case-to-case basis. Although there is no treatment for asymptomatic jejunal diverticulosis and Meckel diverticulitis, it should always be kept in mind that they may cause potentially serious complications.

Background: Recently, the evaluation of the tumor size and local extension of early-stage uterine cervical cancer on magnetic resonance imaging is important for the accurate clinical staging and to determine the indication of less extensive surgery such as fertility sparing radical trachelectomy. Purpose: To compare the diagnostic ability of reduced field-of-view diffusion-weighted imaging with those of three-dimensional (3D) contrast-enhanced T1-weighted imaging and T2-weighted imaging for assessing the tumor margin delineation and local extent of uterine cervical cancer. Material and Methods: 3T magnetic resonance images, including T2-weighted imaging, reduced field-of-view diffusion-weighted imaging, and 3D contrast-enhanced T1-weighted imaging, in 27 women with surgically proven cervical cancer (19 FIGO stage IB1, 3 IB2, and 5 IIA1) were retrospectively evaluated. Tumor margins and local tumor extent, including the presence of invasion to parametrium and vagina were evaluated on both sagittal and oblique axial (short axis) images; the results were compared with histologically confirmed tumor extension. Results: Reduced field-of-view diffusion-weighted imaging diagnosed the tumor margins, which was more accurate than T2-weighted imaging (P <0.001) and slightly better than 3D contrast-enhanced T1-weighted imaging. Reduced field-of-view diffusion-weighted imaging could define the tumor margins well even in small lesions (≤ 20 mm). Histological examination revealed parametrial invasion in two cases (clinically under-staged) and vaginal invasion in four cases. Reduced field-of-view diffusion-weighted imaging could demonstrate local extension of all lesions, which was more accurate than clinical examination and T2-weighted imaging. Conclusion: Addition of reduced field-of-view diffusion-weighted imaging may improve the staging accuracy of magnetic resonance imaging for cervical cancer in assessing the local tumor extent. [ABSTRACT FROM AUTHOR]

Quantitative T2-mapping using magnetic resonance imaging (MRI) allows measurement of tissue T2-relaxation times to complement anatomical and spatial information derived from T2-weighted imaging. Studies have shown varying T2-relaxation times between prostate malignancy and non-malignant prostatic tissue. This paper aims to critically review the literature in a systematic review, to determine the usefulness of T2-mapping in the evaluation of prostate malignancy. A literature search of PubMed and Embase databases was performed. There were 17 studies, up to 31 June 2018, that measured T2-relaxation times of prostate cancer and non-malignant prostatic tissue. Data reviewed from each study included: number of patients and regions of interest evaluated; patient age; study design; T2-mapping technique utilized; reported T2-relaxation values; method of data analysis; method of "ground-truth" assessment; and reported limitations. The T2-relaxation times of prostate cancer and non-malignant prostatic tissue were compared. The T2-relaxation times in the transition zone (TZ) are generally lower than the peripheral zone (PZ). The T2-relaxation times in prostate malignancy are significantly lower than normal PZ in all the studies that performed a statistical comparison. In three out of four studies that performed a statistical comparison, there was no significant difference in the T2-relaxation times between prostate malignancy and non-malignant TZ. T2-mapping appears useful in identifying prostate malignancy in the peripheral zone but is unable to reliably distinguish prostate malignancy and non-malignant transition zone. Further studies are recommended to determine if T2-mapping can improve diagnostic accuracy when used in conjunction with multiparametric MRI for detection of prostate malignancy. [ABSTRACT FROM AUTHOR]

Background: Residual tumor volume (RTV) and extent of resection (EOR) have previously been shown to affect survival in glioblastoma (GB) patients. Quantitative radiological assessment (QRA) of these factors could potentially affect clinical decision-making in the postoperative period.Purpose: The first aim was to evaluate the reproducibility of different volume estimation methods of RTV and EOR by comparing QRA with subjective visual estimation and with objective volume estimations. The second aim was to clarify whether QRA of RTV and EOR would provide accuracy in predicting progression-free survival (PFS) and overall survival (OS) in GB patients.Material and Methods: Seventy GB patients were studied retrospectively. Reproducibility of QRA was compared to conventional visual analysis. Intra-rater agreement between two repeated measurements of 25 patients was calculated. QRA for RTV and EOR was made for the entire study population. Survival analysis was performed by multivariate cox-regression analysis.Results: QRA of RTV and EOR gave superior intra-rater agreement compared to subjective evaluation. Multivariate survival analysis showed prognostic significance on 18 months PFS (hazard ratio [HR] = 0.44, P = 0.003) and OS (HR = 0.42, P = 0.012) at RTV < 1.6 mL and with EOR > 96% on PFS (HR = 2.152, P = 0.005) but not on OS (HR = 1.92, P = 0.053).Conclusion: QRA of tumor volumes is more robust compared to standard evaluation methods. Since EOR and RTV are correlated to the prognosis in GB, quantitative analysis of tumor volumes could aid decision-making and patient management postoperatively. [ABSTRACT FROM AUTHOR]

Purpose To compare the Lung Imaging Reporting and Data System (Lung-RADS) version 1.1 with version 2022 classification of airway nodules detected at lung cancer screening CT examinations. Materials and Methods This retrospective study included all patients who underwent a lung cancer screening CT examination in the authors' health care network between 2015 and 2021 with a reported airway or endobronchial nodule. A fellowship-trained cardiothoracic radiologist reviewed these CT images and characterized the airway nodules by size, location, multiplicity, morphology, dependent portions of airway, internal air, fluid attenuation, distal changes, outcome at follow-up, and final pathologic diagnosis, if malignant. Sensitivity and specificity of Lung-RADS version 1.1 in detecting malignant nodules were compared with those of Lung-RADS version 2022 using the McNemar test. Results A total of 174 patients were included. Of these, 163 (94%) had airway nodules that were deemed benign, while 11 (6%) had malignant nodules. Airway nodules in the trachea and mainstem bronchi were all benign, while lobar and segmental airway nodules had the highest risk for lung cancer (17.2% and 11.1%, respectively). Of the 12 subsegmental airway nodules that were obstructive, three (25%) were malignant and nine (75%) were benign. Nodules with nonobstructive morphologies, dependent portions of airway, internal air, or fluid attenuation were all benign. Only 10 of the 92 (10.9%) patients with positive Lung-RADS by clinical report had cancer. Lung-RADS version 2022 resulted in higher specificity than version 1.1 (82% vs 50%, P < .001), without sacrificing sensitivity (91% for both). Conclusion Compared with the previous version, Lung-RADS version 2022 reduced the number of false-positive screening CT examinations while still identifying malignant airway nodules. Keywords: CT, Lung, Primary Neoplasms, Pulmonary, Lung Cancer Screening, Lung-RADS, Nodule Risk, Airway Nodule, Endobronchial Nodule © RSNA, 2024.

Background: Comparable oncological outcomes have been seen after surgical nephrectomy and thermal ablation of renal tumors recently. However, periprocedural outcome needs to be assessed for aiding treatment decision.Purpose: To compare efficacy rates and periprocedural outcome (technical success, session time, hospitalization time, and complications) after renal tumor treatment with laparoscopic partial nephrectomy (LPN) or radiofrequency ablation (RFA).Material and Methods: The initial experience with 49 (treated with LPN) and 84 (treated with RFA) consecutive patients for a single renal tumor (diameter ≤ 5 cm, limited to the kidney) during 2007-2014 was evaluated. Patient and tumor characteristics, efficacy rates, and periprocedural outcome were collected retrospectively. The stratified Mantel Haenzel and Van Elteren tests, adjusted for tumor complexity (with the modified R.E.N.A.L nephrometry score [m-RNS]), were used to assess differences in treatment outcomes.Results: Primary efficacy rate was 98% for LPN and 85.7% for RFA; secondary efficacy rate was 93.9% for LPN and 95.2% for RFA; and technical success rate was 87.8% for LPN and 100% for RFA. Median session (m-RNS adjusted P < 0.001; LPN 215 min, RFA 137 min) and median hospitalization time were longer after LPN (m-RNS adjusted P < 0.001; LPN 5 days, RFA 2 days). Side effects were uncommon (LPN 2%, RFA 4.8%). Complications were more frequent after LPN (m-RNS adjusted P < 0.001; LPN 42.9%, RFA 10.7%).Conclusion: Both methods achieved equivalent secondary efficacy rates. RFA included several treatment sessions, but session and hospitalization times were shorter, and complications were less frequent than for LPN. The differences remained after adjustment for renal tumor complexity. [ABSTRACT FROM AUTHOR]

Background: The prevalence of intracranial neoplasms in dogs represents 2.1 to 4.0% of the cases. Brain tumors may be primary or metastatic. The objective of this study was to describe two cases of intra encephalic neoplasia in elderly dogs received for necropsy by the Veterinary Oncology Service in the Federal University of Pelotas. Cases: Case 1: A 12-year-old female canine, without breed and medium size, was received for necropsy. The animal has had behavioral changes. Macroscopic examination of the encephalus revealed asymmetry and congestion. The organs were collected and fixed in 10% formalin. In the brain cleavage we noticed an extensive brown-gray mass with reddish areas, expansive, moderately demarcated, soft to cut and discrete hydrocephalus. Serial fragments of the brain and fragments of the organs were sent for processing. The slides were stained with the hematoxylin and eosin technique for histopathological analysis. At the microscopic examination, cuboidal cells were observed in the encephalus sometimes in acinar arrangements, of extensive and very limited pattern, diagnosed as ependymoma. Case 2: It is a 15-year-old, female Poodle dog, with several tumors. During necropsy multiple subcutaneous nodules, mesentery, intestinal serosa, stomach and liver were noticed. At the cut these were firm and whitish. No macroscopic changes were observed in the other organs. Fragments of organs and brain were collected and a serial section of the encephalus was performed for further processing and histological analysis. In the histopathological analysis the masses were constituted by proliferation of sometimes rounded cells, elongated, with rounded nuclei and eosinophilic cytoplasm, allowing the diagnosis of mesothelioma. The same cell pattern was observed in other organs. In the frontal cortex of the encephalus there were small foci of cells similar to those observed in the mesentery, as well as metastatic emboli in the meningeal and encephalic vessels, characterizing the diagnosis of metastatic mesothelioma. Discussion: Neoplasms of the central nervous system may be primary or metastatic. The ependymoma observed in case 1 was only diagnosed after visualization of the encephalic mass during necropsy, pointing to the importance of postmortem examination. Brain neoplasms in dogs occur with a frequency and variety similar to that of humans. Most of these are found in older dogs, and 95% of those affected are over five years of age. One situation that may occur in ependymomas is the development of obstructive hydrocephalus by the expansion of the neoplasm into the ventricular system. The animal studied in case 1 presented behavioral changes for weeks before death, and at necropsy ventricular dilation was evidenced, suggesting that hydrocephalus had occurred and the behavioral changes due to tumor localization. Metastatic brain neoplasms occur due to the hematogenous spread of many tumors. The species in which the metastatic neoplasms are most commonly described is the canine. Metastases of mesotheliomas in the central nervous system are rare, which reinforces the need for a thorough postmortem examination, as evidenced in the second case of this study, since the animal did not manifest clinically signs of neurological involvement and the metastasis was only identified microscopically by serial cuts of the encephalon. It can be concluded that detailed, systematic and serial post-mortem examination of the central nervous system should be part of the diagnostic routine even if no clinical neurological signs are evident. The reports presented here are of importance since they are considered rare diagnoses of primary and metastatic brain tumors. [ABSTRACT FROM AUTHOR]

Background Active surveillance (AS) of low-risk prostate cancer (PCa) is an accepted alternative to active treatment. However, the conventional diagnostic trans-rectal ultrasound guided biopsies (TRUS-bx) underestimate PCa aggressiveness in almost half of the cases, when compared with the surgical specimen. Purpose To investigate if additional multi-parametric magnetic resonance imaging (mpMRI) of the prostate and MRI-guided in-bore biopsies (MRGB) at AS inclusion would improve selection of patients for active treatment. Material and Methods All patients enrolled in AS programs at two Danish centers, from October 2014 to January 2016, were offered an mpMRI 8-12 weeks after the initial diagnostic TRUS-bx. Candidates had low-risk disease (PSA < 10 ng/mL,  6 or GS 6 (3 + 3) lesions with ≥ 6 mm maximal cancer core length (MCCL). Results A total of 78 patients were included and in 21 patients a total of 22 PIRADS-score 4 or 5 lesions were detected. MRGB pathology revealed that 17 (81%) of these and 22% of the entire AS population harbored significant cancers at AS inclusion. In eight (38%) cases, the GS was upgraded. Also, nine patients (43%) had GS 6 (3 + 3) foci with MCCL ≥ 6 mm. Conclusion In an AS cohort based on TRUS and TRUS-bx diagnostic strategies, supplemental mpMRI and in-bore MRGB were able to efficiently reclassify a substantial number of patients as candidates for immediate active treatment. [ABSTRACT FROM AUTHOR]

Background Pancreatic neuroendocrine tumors (PNET) include heterogeneous tumors with a variable degree of inherent biologic aggressiveness represented by the histopathologic grade. Although several studies investigated the computed tomography (CT) characteristics which can predict the histopathologic grade of PNET, accurate prediction of the PNET grade by CT examination alone is still limited. Purpose To investigate the important CT findings and CT texture variables for prediction of grade of PNET. Material and Methods Sixty-six patients with pathologically confirmed PNETs (grade 1 = 45, grades 2/3 = 21) underwent preoperative contrast-enhanced CT. Two reviewers determined the presence of predefined CT findings. CT texture was also analyzed on arterial and portal phase using both two-dimensional (2D) and three-dimensional (3D) analysis. Multivariate logistic regression analysis was performed in order to identify significant predictors for tumor grade. Results Among CT findings and CT texture variables, the significant predictors for grade 2/3 tumors were an ill-defined margin (odds ratio [OR] = 7.273), lower sphericity (OR = 0.409) on arterial 2D analysis, higher skewness (OR = 1.972) and lower sphericity (OR = 0.408) on arterial 3D analysis, lower kurtosis (OR = 0.436) and lower sphericity (OR = 0.420) on portal 2D analysis, and a larger surface area (OR = 2.007) and lower sphericity (OR = 0.503) on portal 3D analysis ( P < 0.05). Diagnostic performance of texture analysis was superior to CT findings (AUC = 0.774 vs. 0.683). Conclusion CT is useful for predicting grade 2/3 PNET using not only the imaging findings including an ill-defined margin, but also the CT texture variables such as lower sphericity, higher skewness, and lower kurtosis. [ABSTRACT FROM AUTHOR]

Background Automated breast volume scanner (ABVS) is an ultrasound (US) device with a wide scanner that sweeps over a large area of the breast and the acquired transverse images are sent to a workstation for reconstruction and review. Whether ABVS is as reliable as handheld US is, however, still not established. Purpose To compare the sensitivity and specificity of ABVS to handheld breast US for detection of breast cancer, in the situation of recall after mammography screening. Material and Methods A total of 113 women, five with bilateral suspicious findings, undergoing handheld breast US due to a suspicious mammographic finding in screening, underwent additional ABVS. The methods were assessed for each breast and each detected lesion separately and classified into two categories: breasts with mammographic suspicion of malignancy and breasts with a negative mammogram. Results Twenty-six cancers were found in 25 women. In the category of breasts with a suspicious mammographic finding (n = 118), the sensitivity of both handheld US and ABVS was 88% (22/25). The specificity of handheld US was 93.5% (87/93) and ABVS was 89.2% (83/93). In the category of breasts with a negative mammography (n = 103), the sensitivity of handheld US and ABVS was 100% (1/1). The specificity of handheld US was 100% (102/102) and ABVS was 94.1% (96/102). Conclusion ABVS can potentially replace handheld US in the investigation of women recalled from mammography screening due to a suspicious finding. Due to the small size of our study population, further investigation with larger study populations is necessary before the implementation of such practice. [ABSTRACT FROM AUTHOR]

Background: There is conflicting opinion as to the optimum extent of resection for right-sided colonic cancer, which is currently graded by pathological analysis of the resected specimen. It is not known if computed tomography (CT) analysis of residual post-resection arterial stump length could be used as an alternative in vivo marker for extent of mesenteric resection. Ileocolic artery stumps have been demonstrated previously on CT after right hemicolectomy, but only in the early postoperative period.Purpose: To analyze preoperative right colonic arterial anatomy using portal venous colorectal cancer staging CT and subsequently determine if post-resection arterial stumps (a potential in vivo marker of surgical resection) could be consistently identified using routine follow-up CT scans many months after cancer resection.Material and Methods: A retrospective analysis of routine staging and follow-up CT scans for 151 patients with right-sided colorectal cancer was performed. Preoperative right colonic arterial anatomy and postoperative arterial stumps were analyzed and measured.Results: Preoperative ileocolic (98.8%), middle (94.7%), and right colic artery (23.8%) identification was comparable to catheter angiogram studies. Postoperative ileocolic stumps were consistently demonstrated (88.3%) many months (average, 2 years and 42 days) after resection and were significantly longer than expected for a standard D2 resection (paired t-test, t(127) = -11.45, P ≤ 0.001).Conclusion: This is the first study to successfully demonstrate ileocolic arterial stumps many months (and years) after cancer resection using routine portal venous CT. Further prospective research should assess whether arterial stumps can be used as an in vivo marker of surgical quality and extent. [ABSTRACT FROM AUTHOR]

Background: Cancer-related obstruction of large abdominal and pelvic veins might become symptomatic with clinical signs of lower limb venous congestion. Technical and clinical outcome after interventional treatment is not well studied yet.Purpose: To retrospectively assess the technical and clinical outcome of endovascular management of symptomatic cancer-related iliocaval venous obstructive disease.Material and Methods: From 1998 to 2013, 19 patients (15 men, 4 women; mean age, 63.6 years) referred for interventional treatment of cancer-related iliocaval obstructive disease were identified. Patients' symptoms included unilateral (n = 16; 84%) or bilateral (n = 3; 16%) painful swelling of the lower limbs. Patients' demographics as well as interventional and clinical outcome data were collected.Results: All 19 patients underwent, under local anesthesia, stenting of the iliac vein (n = 16; 84%) or inferior vena cava (n = 3; 16%). Immediate technical success (n = 19) was 100%; immediate clinical success (n = 18) was 94.7%. During follow-up, seven patients (36.8%) presented with recurrent symptoms of painful limb swelling. Estimated survival after 3 and 6 months was 68.4% (95% confidence interval [CI], 47.8-82.3%) and 19.8% (95% CI, 11.9-29.2%), respectively.Conclusion: Endovascular stenting of cancer-related iliocaval venous obstructive disease is safe and results in immediate relief of symptoms. However, recurrent venous obstruction is common. At 3 months follow-up, the majority of patients with iliac vein stenting were still alive. [ABSTRACT FROM AUTHOR]

Background: Tumor volumetry with magnetic resonance imaging (MRI) is very common; however, the accuracy of such measures remains unclear, especially after treatment.Purpose: To determine the accuracy of preoperative volume measurements of uterine cervical carcinomas resected with and without neoadjuvant chemotherapy (NAC) on T2-weighted (T2W) and diffusion-weighted (DWI) MRI.Material and Methods: Twenty-nine consecutive patients with surgically confirmed uterine cervical carcinoma were included in this study. MRI scans were performed before preoperative treatment in 17 patients and after two courses of NAC in 12 patients. In all patients, T2W images and DWI were obtained to measure the tumor diameters. The maximum diameter of the surgical specimens was macroscopically measured. The correlation coefficients between the measured tumor size using T2W imaging and DWI and the size measured on the surgical specimens were calculated for all specimens.Results: The correlation coefficient of the three-dimensional (3D) tumor volume measurement using T2W imaging and DWI was 0.97 in the primary surgery group and was 0.96 in the NAC group. The 3D tumor volume measurement using MRI and the measurement of the actual surgical specimen was 0.55 for T2WI and 0.48 for DWI in the primary surgery group and 0.88 for T2WI and 0.95 for DWI in the NAC group.Conclusion: T2WI and DWI can provide accurate 3D tumor volume measurements of uterine cervical carcinomas in patients with and without preoperative chemotherapy, suggesting that tumor volumetry using 3 T MRI after uterus-preserving treatment is feasible. [ABSTRACT FROM AUTHOR]

Background: Given that transarterial chemoembolization (TACE) is usually a repeated procedure for treatment of hepatocellular carcinoma (HCC), repeated radiologic response assessments rather than a single time point assessment may have different clinical implications through the repeated course of TACE.Purpose: To evaluate the efficacy of RECIST and mRECIST criteria as a survival predictor across early time points after repeated TACE of HCC.Material and Methods: Ninety-eight patients with intermediate stage HCC received repeated iodized oil TACE. Treatment response was assessed according to RECIST and mRECIST criteria at 1, 3, and 6 months after initial TACE. Cox proportional model was used for survival analysis and the predicting power of each time point response was evaluated with C-statistics and time-dependent area under the receiver operating characteristic curve (AUC). Inter-method agreement was assessed with the κ coefficient.Results: mRECIST was not applicable in 15 patients because of patchy uptake of iodized oil after TACE. On multivariate analysis, responders at 6 months by RECIST, responders at 3 months, and 6 months by mRECIST showed better survival than non-responders (P < 0.05). Predicting power of response criteria improved over time and mRECIST at 6 months showed the best performance. The degree of agreements was poor or fair between RECIST and mRECIST.Conclusion: mRECIST predicted long-term survival as early as 3 months after TACE of intermediate stage HCC. The predicting power of the uni-dimensional response criteria tended to be stronger over time. [ABSTRACT FROM AUTHOR]

Background: The prognosis of glioma patients is contingent on precise target selection for stereotactic biopsies and the extent of tumor resection. 11C-L-methionine (MET) positron emission tomography (PET) demonstrates tumor heterogeneity and invasion with high diagnostic accuracy. Purpose: To compare the spatial tumor distribution delineated by MET PET with that by perfusion- and diffusion-weighted magnetic resonance imaging (MRI), in order to understand the diagnostic value of these MRI methods, when PET is not available. Material and Methods: Presurgical MET PET and MRI, including perfusion- and diffusion-weighted MRI, were acquired in 13 patients (7 high-grade gliomas, 6 low-grade gliomas). A quantitative volume of interest analysis was performed to compare the modalities objectively, supplemented by a qualitative evaluation that assessed the clinical applicability. Results: The inaccuracy of conventional MRI was confirmed (area under the curve for predicting voxels with high MET uptake = 0.657), whereas cerebral blood volume (CBV) maps calculated from perfusion data improved accuracy (area under the curve = 0.760). We considered CBV maps diagnostically comparable to MET PET in 5/7 cases of high-grade gliomas, but insufficient in all cases of low-grade gliomas when evaluated subjectively. Cerebral blood flow and apparent diffusion coefficient maps did not contribute to further accuracy. Conclusion: Adding perfusion-weighted MRI to the presurgical protocol can increase the diagnostic accuracy of conventional MRI and is a simple and well-established method compared to MET PET. However, the definition of low-grade gliomas with subtle or no alterations on cerebral blood volume maps remains a diagnostic challenge for stand-alone MRI. [ABSTRACT FROM AUTHOR]