Does dual-energy CT differentiate benign and malignant ovarian tumours?

AIM: To assess the ability of dual-energy computed tomography (DECT) to distinguish benign from malignant ovarian tumours (OTs). MATERIALS AND METHODS: Following approval of the institutional review board, the institutional database was mined for treatment-naive patients who underwent primary cytoreduction for OT. Thirty-seven patients were included and divided into those with benign OTs (n = 11) and malignant OTs (n = 26), including high-grade (n = 20) and low-grade (n = 6) malignant OTs. Advanced processing and region of interest delineation on the ovarian mass were performed using the preoperative staging DECT examination using the Advantage Workstation. The pixel-level data of the CT attenuation values at 50, 70, and 120 keV and the effective atomic number (Zeff), water content (WC), and iodine content (IC) in the ovarian mass were recorded. The Wilcoxon rank-sum test was used to compare CT attenuation data at different voltages, Zeff, and WC and IC levels between benign and malignant OTs and between high- and low-grade malignant OTs. Simple logistic regression was used to correlate the imaging characteristics with malignant status and grade. RESULTS: Malignant OTs had significantly higher Zeff and IC compared with benign OTs. The threshold values for the diagnosis of malignant OT were IC≥9.74 (100 µg/cm3) with 81% sensitivity and 73% specificity and Zeff ≥8.16 with 85% sensitivity and 73% specificity. High-grade OTs had significantly higher WC compared with low-grade OTs, and a threshold of ≥1,013.92 mg/cm3 differentiated them with 80% sensitivity and 83% specificity. CONCLUSION: DECT may be a tool to help distinguish malignant and benign OTs and predict tumour grade.

Machine learning-based texture analysis for differentiation of large adrenal cortical tumours on CT.

AIM: To compare the efficacy of computed tomography (CT) texture analysis and conventional evaluation by radiologists for differentiation between large adrenal adenomas and carcinomas. MATERIALS AND METHODS: Quantitative CT texture analysis was used to evaluate 54 histopathologically proven adrenal masses (mean size=5.9 cm; range=4.1-10 cm) from 54 patients referred to Anderson Cancer Center from January 2002 through April 2014. The patient group included 32 women (mean age at mass evaluation=59 years) and 22 men (mean age at mass evaluation=61 years). Adrenal lesions seen on precontrast and venous-phase CT images were labelled by three different readers, and the labels were used to generate intensity- and geometry-based textural features. The textural features and the attenuation values were considered as input values for a random forest-based classifier. Similarly, the adrenal lesions were classified by two different radiologists based on morphological criteria. Prediction accuracy and interobserver agreement were compared. RESULTS: The textural predictive model achieved a mean accuracy of 82%, whereas the mean accuracy for the radiologists was 68.5% (p<0.0001). The interobserver agreements between the predictive model and radiologists 1 and 2 were 0.44 (p<0.0005; 95% confidence interval [CI]: 0.25-0.62) and 0.47 (p<0.0005; 95% CI: 0.28-0.66), respectively. The Dice similarity coefficient between the readers' image labels was 0.875±0.04. CONCLUSION: CT texture analysis of large adrenal adenomas and carcinomas is likely to improve CT evaluation of adrenal cortical tumours.

Imaging and Staging of Endometrial Cancer.

Endometrial carcinoma is the most common female pelvic malignancy in the United States. Although endometrial cancer is staged according to the International Federation of Gynecology and Obstetrics surgical system, early and accurate diagnostic assessment of disease status of gynecologic malignancies is important for optimal treatment planning and outcome prediction. Preoperative imaging may assist in evaluation of local extent and detection of distant metastatic disease guiding the optimal course of treatment. Several imaging techniques such as transvaginal ultrasound, computed tomography, and magnetic resonance imaging have been used as tools for preoperative staging of endometrial cancer. Positron emission tomography/computed tomography and more recently, positron emission tomography/magnetic resonance imaging have also been used in the management of endometrial cancer. Cross-sectional imaging, especially MRI, may detect gross myometrial invasion or extension of tumor to the cervical stroma which can alter management. Imaging studies can also evaluate the presence of lymph nodal involvement, and detect local and distant metastatic disease at diagnosis. Additionally, imaging also plays a role in the monitoring of treatment and surveillance of the patients for detection of early recurrent disease. In this article, we will review the imaging and staging of endometrial cancer.

Uterine Carcinosarcomas.

Uterine carcinosarcoma (UCS) is a rare and aggressive variant of endometrial cancer, distinguished by its containment of both epithelial and sarcomatous elements. This article reviews the epidemiology, pathologic classification and staging of UCS, along with the typical findings seen on different imaging modalities. Prognosis and therapies will also be discussed.

Ischiorectal fossa: benign and malignant neoplasms of this "ignored" radiological anatomical space.

PURPOSE: To review the pertinent anatomy and the imaging features of common and uncommon benign and malignant neoplasms and masses of the ischiorectal fossa. RESULTS: The ischiorectal or ischioanal fossa is the largest space in the anorectal region. The benign neoplasms that develop in the ischiorectal originate from the different components that forms the fossa including vascular tumors such as aggressive angiomyxoma or hemangioma; neural tumors as plexiform neurofibroma or schwannoma; fat tumors as lipoma; skin/skin appendages tumors as hidradenoma papilliferum; smooth or skeletal muscle tumors as solitary fibrous tumor. The malignant neoplasms that develop in the ischiorectal fossa also originate from different components that forms the fossa including vascular tumors such as angiosarcoma, neural tumors as malignant granular cell tumor and malignant peripheral nerve sheath tumor; fat tumors as liposarcoma; smooth or skeletal muscle tumors as leiomyosarcoma, rhabdomyosarcoma, malignant PEComa, or undifferentiated pleomorphic sarcoma. Additionally, the ischiorectal fossa can also harbor secondary hematogenous metastases and be affected by direct invasion from neoplasms of adjacent pelvic organs and structures. Furthermore, other miscellaneous masses can occur in the ischiorectal fossa including congenital and developmental lesions, and inflammatory and infectious processes. CONCLUSION: Knowledge of the anatomy, and the spectrum of imaging findings of common and uncommon benign and malignant neoplasms of the ischiorectal fossa is crucial for the radiologists during interpretation of images allowing them to make contributions to the diagnosis and better patient management.

Tumor markers: myths and facts unfolded.

OBJECTIVE: The purpose of this article is to review the most commonly used tumor markers in abdominal and pelvic tumors, describe their limitations and explain how to use them in the context of known cancer in order to optimize multidisciplinary care of oncologic patients. CONCLUSION: Tumor markers are important for the diagnosis, staging, monitoring of treatment and detection of recurrence in many cancers. This knowledge is crucial in the daily interpretation of images of oncologic and non-oncologic patients. However, radiologists should also be aware of the limitations of the most commonly used tumor markers and they should not be used solely, but interpreted in conjunction with diagnostic imaging, clinical history and physical examination that will help optimize the multidisciplinary care and management of oncologic patients.

Can MRI help assess aggressiveness of endometrial cancer?

AIM: To identify potential magnetic resonance imaging (MRI) biomarkers to predict the aggressiveness of endometrial cancer. MATERIALS AND METHODS: Seventy-one patients with endometrial cancer who underwent MRI staging were analysed retrospectively. The signal intensity (SI) of the tumours was assessed on sagittal T2-weighted imaging (WI) and sagittal T1WI sequences). The depth of myometrial invasion, tumour grade and subtype, lymphovascular invasion, and microsatellite stability status were assessed histopathologically, and these findings were compared with MRI findings using logistic regression. The log-rank test was used to assess differences in survival among groups defined by different MRI measurements. RESULTS: Tumours with qualitative higher signal than that of normal myometrium on the late T1WI DCE image sequences were more likely to have lymphovascular space invasion (p<0.001). Tumours that had a higher SI tumour ratio (T1 post-contrast arterial/T1 precontrast) had a higher chance of being microsatellite stable (odds ratio 2.36). The SI ratio of the tumour to the myometrium showed that lower T2 tumour/T2 myometrial ratio correlated with ≥50% depth of myometrial invasion as determined by imaging (p=0.006). Endometrial tumours showing a SI of >209 on delayed T1WI sequences had longer recurrence-free survival than those with tumours showing a SI ≤209 (p=0.014). Tumour subtype and grade were not associated with MRI findings. CONCLUSION: The SI of endometrial cancer on MRI may be used to predict the aggressiveness of the tumour and microsatellite stability status. Further studies are needed to confirm these findings.

Mimicking the Synaptic Weights and Human Forgetting Curve Using Hydrothermally Grown Nanostructured CuO Memristor Device.

In the present investigation, we have fabricated copper oxide (CuO) thin film memristor by employing a hydrothermal method for neuromorphic application. The X-ray diffraction pattern confirms the films are polycrystalline in nature with the monoclinic crystal structure. The developed devices show analog memory and synaptic property similar to biological neuron. The size dependent synaptic behavior is investigated for as-prepared and annealed CuO memristor. The results suggested that the magnitude of synaptic weights and resistive switching voltages are dependent on the thickness of the active layer. Synaptic weights are improved in the case of the as-prepared device whereas they are inferior for annealed CuO memristor. The rectifying property similar to a biological neuron is observed only for the as-prepared device, which suggested that as-prepared devices have better computational and learning capabilities than annealed CuO memristor. Moreover, the retention loss of the CuO memristor is in good agreement with the forgetting curve of human memory. The results suggested that hydrothermally grown CuO thin film memristor is a potential candidate for the neuromorphic device development.

Imaging findings of recurrent pancreatic cancer following resection.

Pancreatic cancer is a challenging malignancy to treat, largely due to aggressive regional involvement, early systemic dissemination, high recurrence rate, and subsequent low patient survival. Generally, 15-20% of newly diagnosed pancreatic cancers are candidates for possible curative resection. Eighty percent of these patients, however, will experience locoregional or distant recurrence in first 2 years. Although there is no strong evidence-based guideline for optimal surveillance after pancreatic cancer resection, careful comparison of surveillance follow-up multi-detector CT (MDCT) studies with a postoperative baseline MDCT examination aids detection of early recurrent pancreatic cancer. In this review article, we describe imaging findings suggestive of recurrent pancreatic cancer and review routine and alternative imaging options.

A Diagnostic Challenge: Pancreatic Cancer or Autoimmune Pancreatitis?

We report a rare case of seronegative autoimmune pancreatitis (AIP) that presented as a pancreatic focal lesion and was considered to be pancreatic cancer based on the clinical presentation and imaging findings. The endoscopic ultrasound-guided biopsies of the pancreatic mass revealed no malignant cells and the pancreatic swelling had become diffuse on repeat imaging. AIP was suspected and a trial of steroids was considered as a diagnostic and therapeutic method. The patient responded dramatically to corticosteroid treatment with resolution of symptoms and normal imagining and laboratory parameters. This case highlights the challenge in the diagnostic approach of a pancreatic mass.

Is MRI helpful in assessing the distance of the tumour from the internal os in patients with cervical cancer below FIGO Stage IB2?

AIM: To determine the ability of magnetic resonance imaging (MRI) in detecting tumour-free margins from the internal os (IO). MATERIALS AND METHODS: A database search yielded 79 women with early-stage cervical cancer who underwent radical hysterectomy and preoperative MRI. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MRI in assessment of ≤5 and >5 mm IO involvement were calculated with histopathological surgical specimen findings considered to be the reference standard. A main and subset analysis was performed. The subset analysis included only those patients who would have been considered for radical trachelectomy. RESULTS: For predicting a distance between the tumour and the IO of ≤5 mm, MRI had a sensitivity of 73%, a specificity of 98.3%, a PPV of 95%, a NPV of 88.1%, and an accuracy of 89.8% for the main analysis, and sensitivity of 81.8%, a specificity of 93.2% a PPV of 69.2% a NPV of 96.5% and an accuracy of 91.4% for the subset analysis. CONCLUSION: MRI has high specificity, NPV, and accuracy in detecting tumour from the IO, making MRI suitable for treatment planning in patients desiring trachelectomy to preserve fertility.

Development of RP UPLC-TOF/MS, stability indicating method for omeprazole and its related substances by applying two level factorial design; and identification and synthesis of non-pharmacopoeial impurities.

A new UPLC-TOF/MS compatible, reverse phase-stability indicating method was developed for determination of Omeprazole (OMP) and its related substances in pharmaceutical dosage forms by implementing Design of Experiment (DoE) i.e. two level full factorial Design (2(3)+3 center points=11 experiments) to understand the Critical Method Parameters (CMP) and its relation with Critical Method Attribute (CMA); to ensure robustness of the method. The separation of eleven specified impurities including conversion product of OMP related compound F (13) and G (14) i.e. Impurity-I (1), OMP related compound-I (11) and OMP 4-chloro analog (12) was achieved in a single method on Acquity BEH shield RP18 100 × 2.1 mm, 1.7 µm column, with inlet filter (0.2 µm) using gradient elution and detector wavelength at 305 nm and validated in accordance with ICH guidelines and found to be accurate, precise, reproducible, robust and specific. The drug was found to degrade extensively in heat, humidity and acidic conditions and forms unknown degradation products during stability studies. The same method was used for LC-MS analysis to identify m/z and fragmentation of maximum unknown impurities (Non-Pharmacopoeial) i.e. Impurity-I (1), Impurity-III (3), Impurity-V (5) and Impurity-VIII (9) formed during stability studies. Based on the results, degradation pathway for the drug has been proposed and synthesis of identified impurities i.e. impurities (Impurity-I (1), Impurity-III (3), Impurity-V (5) and Impurity-VIII (9)) are discussed in detail to ensure in-depth understanding of OMP and its related impurities and optimum performance during lifetime of the product.

Primary vaginal cancer: role of MRI in diagnosis, staging and treatment.

Primary carcinoma of the vagina is rare, accounting for 1-3% of all gynaecological malignancies. MRI has an increasing role in diagnosis, staging, treatment and assessment of complications in gynaecologic malignancy. In this review, we illustrate the utility of MRI in patients with primary vaginal cancer and highlight key aspects of staging, treatment, recurrence and complications.

MRI is highly specific in determining primary cervical versus endometrial cancer when biopsy results are inconclusive.

AIM: To evaluate utility of magnetic resonance imaging (MRI) in determining the primary site of endometrial versus cervical tumours when the biopsy results are inconclusive. MATERIAL AND METHODS: Forty-eight patients who underwent a total hysterectomy for unknown primary adenocarcinoma of the uterus after endometrial and/or endocervical biopsies were included in the study. The 48 available pelvic MRI images were reviewed by two body radiologists independently and jointly to resolve discordance, blinded to any clinical and pathological information. The clinical information and histopathology were reviewed by a radiology fellow and a pathologist specializing is gynaecological oncology. The final surgical pathology was used as the reference standard to confirm the origin of the primary tumour. RESULTS: The radiologists correctly identified the primary sites in 85% of the cases (41/48). There was substantial agreement between the two readers (kappa statistics = 0.79). Both radiologists found that T2 and dynamic T1-weighted images (WI) were most helpful in making the diagnosis, and dynamic T1WI helped resolve problematic cases. The sensitivity and specificity for detecting endometrial and cervical cancer on MRI were 88% and 88% and 75% and 93%, respectively. CONCLUSION: MRI has high sensitivity and specificity in determining the origin of the primary endometrial versus cervical tumours when endometrial/endocervical curettage is inconclusive.

Carcinoid tumours: predicting the location of the primary neoplasm based on the sites of metastases.

OBJECTIVES: To predict the primary neuroendocrine tumour of the gastrointestinal tract site based on observed metastatic sites. METHODS: We studied data from the radiology database of a single, large cancer centre on 250 patients with pathologically confirmed neuroendocrine tumours. Primary tumour sites and the locations of metastases were collected from pathologic and radiologic reports of all available imaging modalities, such as computed tomography (CT), positron emission tomography (PET/CT), magnetic resonance imaging (MRI) and octreotide scans in the database. A nominal regression model was used to predict primary tumour site using the observed metastatic sites. Regression coefficients that were not statistically significant at the 5 % level were eliminated from the model in a stepwise procedure. RESULTS: Lung and liver metastases were not statistically significant predictors of the location of primary tumours (p = 0.86 and 0.074, respectively); whereas, lymph node, bone, and peritoneal metastases were significant predictors (p < 0.0001, 0.0004, and 0.014, respectively). CONCLUSIONS: Metastatic neuroendocrine tumours to the lymph nodes, bone, and peritoneum can be used to predict the primary neuroendocrine site; however, metastases in the lung and liver alone cannot predict the site of the primary tumour site.

CT imaging features of acinar cell carcinoma and its hepatic metastases.

OBJECTIVE: To evaluate and describe the computed tomography features of pure acinar cell carcinoma (ACC) and its liver metastases. METHODS: Thirty patients were evaluated. Two radiologists evaluated imaging findings for each tumor for size, location, internal density, enhancement, tumor calcifications, pancreatic, and common biliary ductal obstructions and metastases. RESULTS: 70 % were male. Fourteen tumors were located in the pancreatic head, 14 in the tail, one in the neck, and one in the uncinate process. Abdominal pain was the most common presenting symptom (93 %), 20 % had pancreatitis and 17 % had obstructive jaundice. The average tumor size was 7 cm, 97 % of tumors were solid, well circumscribed (73 %); isodense to normal pancreatic parenchyma (40 %) on the non-contrast study, hypodense on the arterial (47 %), and hypodense on the portal venous (37 %) phase. 30 % patients had pancreatic ductal dilation, 10 % had pancreatic ductal ingrowth, 6 % had calcifications, and 20 % had central necrosis, and 31 % (5/16) showed biliary ductal dilation. At presentation, 50 % had metastatic adenopathy and 40 % patients had liver metastases, which typically were well circumscribed, hypoattenuating to the hepatic parenchyma on all the phases of contrast enhancement and had a lobulated margin. CONCLUSION: ACCs of the pancreas often present as large, well circumscribed, solid masses commonly in males. Despite their large size, they may not cause CBD obstruction.

CdS-sensitized TiO2 nanocorals: hydrothermal synthesis, characterization, application.

Cadmium sulfide (CdS) nanoparticle-sensitized titanium oxide nanocorals (TNC) were synthesized using a two-step deposition process. The TiO(2) nanocorals were grown on the conducting glass substrates (FTO) using A hydrothermal process and CdS nanoparticles were loaded on TNC using successive ionic layer adsorption and reaction (SILAR) method. The TiO(2), CdS and TiO(2)-CdS samples were characterized by optical absorption, X-ray diffraction (XRD), FT-Raman, FT-IR, scanning electron microscopy (SEM) and contact angle. Further, their photoelectrochemical (PEC) performance was tested in NaOH, Na(2)S-NaOH-S and Na(2)S electrolytes, respectively. When CdS nanoparticles are coated on TNCs, the optical absorption is found to be enhanced and band edge is red-shifted towards visible region. The TiO(2)-CdS sample exhibits improved photoelectrochemical (PEC) performance with maximum short circuit current of (J(sc)) 1.04 mA cm(-2). After applying these TiO(2)-CdS electrodes in photovoltaic cells, the photocurrent was found to be enhanced by 2.7 and 32.5 times, as compared with those of bare CdS and TiO(2) nanocorals films electrodes respectively. Also, the power conversion efficiency of TiO(2)-CdS electrodes is 0.72%, which is enhanced by about 16 and 29 times for TiO(2), CdS samples.

Diagnostic imaging in gynecologic malignancy.

Advances in imaging techniques over the past few decades have continued at an astounding pace and now physicians have various modalities to examine the human body. These imaging techniques may be used to assist in diagnosis, staging, and follow-up of oncology patients. The increasing complexity of diagnostic radiology provides a challenge to radiologists and oncologists to use these tools in a clinically efficient and cost-effective manner. The ultimate goal is to offer a safe and effective examination that provides clinically relevant information for the management of an individual patient. Currently ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) are being used to evaluate patients with gynecological malignancies. Goal of this review is to provide an overview of clinically available imaging techniques and discuss relative strengths and weaknesses. This article summarizes the diagnostic performance (sensitivity, specificity, positive and negative likelihood ratios) of US, CT, MRI and PET/CT in the diagnosis of various gynecological diseases and tumors. US is the first-line imaging modality of choice and is used to discriminate between benign and malignant adnexal masses and for characterizing adnexal tumors such as dermoid cyst, endometrioma, hemorrhagic corpus luteum, etc., for diagnosing intrauterine pathology in women with dysfunctional uterine bleeding, and for confirming or refuting pelvic pathology in women with pelvic pain. MRI can play a role in detecting the extent of disease and helps in local staging of gynecologic tumors. CT can be used to detect extrapelvic disease and PET/CT can assist in detecting distant metastatic disease in order to select appropriate surgical candidates.

Current staging of hepatocellular carcinoma: imaging implications.

The incidence of hepatocellular carcinoma has been rising in the USA in the past two decades. Hepatocellular carcinoma primarily affects older people and reaches its highest prevalence among those aged between 50 and 70 years. Chronic infection by the hepatitis B virus is the most common cause of this disease. Since hepatocellular carcinoma is an indolent tumor, it has a low life expectancy. In patients with suspected hepatocellular carcinoma, CT, MRI, and ultrasound techniques are useful for formulating the diagnosis based on vascularity and specific enhancement features. In this paper we will discuss the multimodal approach for diagnosis and surveillance of hepatocellular carcinoma. We will also furnish the latest staging and treatment, epidemiology, clinical presentation, pathology and laboratory findings in hepatocellular carcinoma.