Development and Validation of a 18F-FDG PET/CT-Based Clinical Prediction Model for Estimating Malignancy in Solid Pulmonary Nodules Based on a Population With High Prevalence of Malignancy

PURPOSE

To develop a prediction model based on ¹⁸F-fludeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) for solid pulmonary nodules (SPNs) with high malignant probability.

PATIENTS AND METHODS

We retrospectively reviewed the records of CT-undetermined SPNs, which were further evaluated by PET/CT between January 2008 and December 2015. A total of 312 cases were included as a training set and 159 as a validation set. Logistic regression was applied to determine independent predictors, and a mathematical model was deduced. The area under the receiver operating characteristic curve (AUC) was compared to other models. Model fitness was assessed based on the American College of Chest Physicians guidelines.

RESULTS

There were 215 (68.9%) and 127 (79.9%) malignant lesions in the training and validation sets, respectively. Eight independent predictors were identified: age [odds ratio (OR) = 1.030], male gender (OR = 0.268), smoking history (OR = 2.719), lesion diameter (OR = 1.067), spiculation (OR = 2.530), lobulation (OR = 2.614), cavity (OR = 2.847), and standardized maximum uptake value of SPNs (OR = 1.229). Our AUCs (training set, 0.858; validation set, 0.809) was better than those of previous models (Mayo: 0.685, P = .0061; Peking University People's Hospital: 0.646, P = .0180; Herder: 0.708, P = .0203; Zhejiang University: 0.757, P = .0699). The C index of the nomogram was 0.858. Our model reduced the diagnosis of indeterminate nodules (26.4% vs. 79.2%, 53.5%, 39.6%, and 34.0%, respectively) while improved sensitivity (81.3% vs. 16.4%, 49.2%, 62.5%, and 68.0%, respectively) and accuracy (65.4% vs. 16.4%, 39.6%, 52.8%, and 58.5%, respectively).

CONCLUSION

Our model could permit accurate diagnoses and may be recommended to identify malignant SPNs with high malignant probability, as our data pertain to a very high-prevalence cohort only.

News in the Indications of Direct Oral Anticoagulants According to the American College of Chest Physicians 2016 Guidelines

BACKGROUND

The 10th edition of the CHEST Guideline and Expert Panel Report for the treatment of venous thromboembolism (VTE) was recently updated with recommendations on both the choice of anticoagulants and the duration of treatment in diverse clinical scenarios.

METHOD

In this paper, we focus on news in the use of direct oral anticoagulants (DOACS), a group of synthetic low molecular weight drugs capable of directly and specifically inhibiting either activated factor X or both free and fibrin- bound thrombin.

RESULTS

New to the guidelines is the recommendation of the use of DOACS over vitamin K-antagonists (VKA´s) in individuals without cancer who develop VTE. The choice and intensity of anticoagulants is the same for lower and upper extremity thrombosis or for pulmonary embolism. For cancer-related thrombosis low molecular weight heparin is still recommended over the use of VKA´s or DOACS, though high quality evidence for this choice is lacking. If therapy is given beyond three months, remaining on the same anticoagulant is suggested. Re-thrombosis while on regular use of DOACs requires switching to low molecular weight heparins at least for one month.

CONCLUSION

Ultimately the choice of anticoagulant will depend on patient-specific factors such as comorbidities, compliance, patient preferences, availability and costs. We address the news in DOAC use in VTE from the perspective of an upper-middle income economy.

Acid-base transport in pancreatic cancer: molecular mechanisms and clinical potential

Solid tumors are characterized by a microenvironment that is highly acidic, while intracellular pH (pHi) is normal or even elevated. This is the result of elevated metabolic rates in the highly proliferative cancer cells, in conjunction with often greatly increased rates of net cellular acid extrusion. Studies in various cancers have suggested that while the acid extrusion mechanisms employed are generally the same as those in healthy cells, the specific transporters upregulated vary with the cancer type. The main such transporters include Na(+)/H(+) exchangers, various HCO3(-) transporters, H(+) pumps, and lactate-H(+) cotransporters. The mechanisms leading to their dysregulation in cancer are incompletely understood but include changes in transporter expression levels, trafficking and membrane localization, and posttranslational modifications. In turn, accumulating evidence has revealed that in addition to supporting their elevated metabolic rate, their increased acid efflux capacity endows the cancer cells with increased capacity for invasiveness, proliferation, and chemotherapy resistance. The pancreatic duct exhibits an enormous capacity for acid-base transport, rendering pHi dysregulation a potentially very important topic in pancreatic ductal adenocarcinoma (PDAC). PDAC - accounting for about 90% of all pancreatic cancers - has one of the highest cancer mortality rates known, and new diagnostic and treatment options are highly needed. However, very little is known about whether pH regulation is altered in PDAC and, if so, the possible role of this in cancer development. Here, we review current models for pancreatic acid-base transport and pH homeostasis and summarize current views on acid-base dysregulation in cancer, focusing where possible on the few studies to date in PDAC. Finally, we present new data-mining analyses of acid-base transporter expression changes in PDAC and discuss essential directions for future work.

Characteristics of patients with rheumatoid arthritis in Qatar: a cross-sectional study

OBJECTIVE

To describe the clinical characteristics, serologic, radiological and clinical disease activity, and modality of therapy in patients with rheumatoid arthritis (RA) at tertiary outpatient care in Qatar.

METHODS

The study design was cross-sectional where 100 consecutive cases who met 1987 American College of Rheumatology criteria for diagnosis of RA were enrolled in this study. Demographic data (sex, nationality and age) numbers of swollen and tender joints, X-rays and current medications were collected during outpatients visits to Hamad General Hospital. Disease Activity Score of 28 joints (DAS28) and Health Assessment Questionnaires (HAQ) scores were calculated. All patients with RA who were seen as rheumatology outpatients were invited to participate in the study.

RESULTS

One hundred patients were seen and examined during their follow-up at the outpatient clinic; data were collected and analyzed. Females represented 67% of all patients, 6% had more than six swollen joints, 9% had more than six tender joints. DAS28 and erythrocyte sedimentation rate (DAS28) calculation revealed 49% of patients were in remission (DAS28 < 2.6), 15% had low disease activity (DAS28 2.6-3.2) and 36% had DAS28 > 3.2.Mean HAQ score was 1.02. Rheumatoid factor (RF) was positive in 63%, while anti-cyclic citrullinated protein antibody (anti-CCP) was positive in 71%, and 49% were positive for both. Radiography of hands and feet during the previous year was done in 65% of patients: 11% of them had erosions. Sixty-six percent were on one synthetic disease-modifying anti-rheumatic drug (DMARD) and 27% where on more than one synthetic DMARD and 7% where on no DMRD. Glucocorticoids were used in 51% and 29% were on biologics.

CONCLUSION

Sixty-four percent of rheumatoid arthritis patients in Qatar were in remission or had low disease activity while the remaining 36% had active disease and among these patients 29% were on biologics.

Comparison of sensitivity and specificity of anti-CCP and anti-MCV antibodies in an Iranian cohort of patients with rheumatoid arthritis

Background : Anti-CCP is a test commonly used for the diagnosis of rheumatoid arthritis. The aim of this study was to determine the diagnostic values of ACCP compared to anti-MCV in rheumatoid arthritis patients in north of Iran.

METHODS

The serum samples of 150 RA patients and 75 controls, with the mean age of 49.6+11.8 and 48.8+12 years respectively, were tested using the commercially available ELISA kits for ACCP and anti-MCV. Sensitivity, Specificity were determined and Roc curve were used for comparison between these two groups.

RESULTS

The sensitivity of ACCP versus anti-MCV was 85% and 81%, respectively. Specificity was 96% and 95%, respectively. In the RA patients, ACCP was positive in 127 (84.7%) and anti MCV in 121 (80.7%) cases. In the control group, these parameters were positive in 3 (4%) and 4 (5.3%) (p<0.0001 and p<0.0001, respectively). The correlation coefficient for ACCP and anti-MCV was calculated at 0.63 (p<0.001). The area under the curve for ACCP was 0.941±0.015 (p<0.001), anti-MCV was 0.902±0.02 (p<0.001). The measure of agreement (Kappa) for these variables was 0.81. In these patients, there was no correlation between DAS28 and the positivity of these tests.

CONCLUSION

It was concluded, compared to ACCP, anti-MCV has approximately the same accuracy for the diagnosis of rheumatoid arthritis and it does not have additional value.