Performance characteristics of the boson rapid SARS-cov-2 antigen test card vs RT-PCR: Cross-reactivity and emerging variants

Background

SARS-CoV-2 virus has undergone several mutations on its genome, since the onset of the pandemic. Multiple variants of concern (VOC) have emerged including Alpha, Beta, Gamma, and Delta with the more recent one being the Omicron (B.1.1.529). Specific rapid antigen tests (RADs) have been used for the detection of SARS-CoV-2. However, since the emergence of new VOCs, the performance characteristics of these RADs needs to be re-evaluated.

Objectives

The main purposes of this clinical study were to determine the diagnostic sensitivity and specificity of the BOSON Rapid Antigen Test compared to the gold standard real time RT-PCR and to determine the ability of the RAD to accurately depict different VOC. Additionally, the cross reactivity to other viruses and pathogen, as well as, the possible interference of non Covid-19 hospitalized patients for various causes, were investigated.

Results

A total of 623 individuals (symptomatic) were tested. The sensitivity, specificity and accuracy of the BOSON RAD was 95.27%, 100% and 98.45% (n = 448), meeting the WHO recommended standards. Additionally, the Delta (83.33%, Ct < 34) and Omicron (100%, Ct < 26) VOC were determined with high sensitivity. Also, there was no interference from hospitalized, non-Covid 19 patients, and no cross-reactivity was detected.

Conclusions

The study showed that this RAD could rapidly identify individuals with SARS-CoV-2, including those with the new dominant Omicron VOC, with no cross reactivity from other pathogens.

Diagnostic capacity of BAP1 and MTAP in cytology from effusions and biopsy in mesothelioma

INTRODUCTION

Serous effusion is often the first sign of mesothelioma. Diagnosis based on cytologic material from the effusions remains controversial and complementary biopsy is usually required. However, obtaining representative tissue sample may be challenging, while obtaining cytologic material is a minimally invasive procedure, providing potential for an earlier diagnosis. Loss of BRCA1-associated protein (BAP1), combined with loss of methylthionadenosine phosphorylase (MTAP) detected by immunohistochemistry, have shown to be reliable markers in the diagnosis of mesothelioma on histologic sections. Here we evaluate the value of these biomarkers in cytologic specimens.

MATERIALS AND METHODS

The BAP1 and MTAP expression in specimens of 162 mesothelioma patients (156 pleural, 6 peritoneal)-71 cytologic, 91 histologic (44 epithelioid, 31 biphasic, 16 sarcomatoid)-and 20 patients with reactive mesothelial proliferations were investigated.

RESULTS

The loss of BAP1 and/or MTAP was highly sensitive and specific in differentiating mesothelioma from reactive mesothelial proliferations, with no significant difference between pleural effusions and biopsies, specificity of 100% in both and a sensitivity of 78.9% and 80.2%, respectively (P = 0.3). There was a 100% concordance of the expression of BAP1 and MTAP in cytologic and corresponding histopathologic samples. Loss of BAP1 and/or MTAP in histologic sections discriminated sarcomatoid, biphasic, and epithelioid mesothelioma from reactive mesothelial proliferations with a sensitivity of 81.2%, 83.9%, and 77.3% respectively.

CONCLUSION

Loss of expression of BAP1 and/or MTAP differentiated mesothelioma from reactive mesothelial proliferations with excellent specificity and high sensitivity in cytologic samples, comparable to histopathologic sections.

Clinical prognostic factors in pleural mesothelioma: best supportive care and anti-tumor treatments in a real-life setting

BACKGROUND

This study aims to investigate patient- and disease characteristics associated with survival in malignant pleural mesothelioma (MPM) patients with anti-tumor treatment or with best supportive care (BSC).

MATERIALS AND METHODS

Consecutive MPM cases diagnosed in North Denmark Region from 1972 to 2015 were reevaluated and verified by two pathologists using modern immunohistochemical techniques. Danish registries and hospital records were used to gather patient-, asbestos exposure-, and disease information.

RESULTS

Of the 279 patients, anti-tumor treatment was administered to 184 patients (66.0%). All of those received chemotherapy alone or as part of a multimodal treatment, where pemetrexed was given to 126 (68.5%) patients. Asbestos exposure was documented in 92.5% of all patients. In the treated group, mean age was lower (66 years versus 74 years, p < 0.01), rate of occupational asbestos exposure was higher (74.5 versus 54.7%, p < 0.01), more patients had better performance score (98.4 versus 60%, p < 0.01) and stage was lower (81 versus 63.2%, p < 0.01) compared to the BSC group. Multivariate analysis showed that epithelioid subtype was the only common prognostic factor for OS in both groups. In BSC patients, good PS and female gender was associated with improved OS. Median overall survival (OS) was 17 versus 4 months (p < 0.01), and independently of the histopathological subtype, the median and 2-year survival was higher in the treated versus the BSC group (p < 0.02).

CONCLUSIONS

This retrospective study showed that epithelioid subtype is the only independent positive prognostic factor of survival in treated patients with MPM. For BSC patients, the epithelioid subtype, good PS, and female gender were positive prognostic factors, while age and comorbidities were not significant. This study with long-term follow-up of treated and BSC MPM patients can contribute to the clinical stratification of patients. Further validation is appropriate to verify these findings.

Adjuvant platinum-based chemotherapy in non-small cell lung cancer: The role of relative dose-intensity and treatment delay

BACKGROUND

The study investigated the association of the relative dose-intensity (RDI) of cisplatin and timing of adjuvant platinum-based chemotherapy (APC) with survival for stage I-III non-small cell lung cancer (NSCLC) patients.

MATERIAL AND METHODS

Real-life data of patients treated with APC (four cycles of cisplatin and vinorelbine) between 2007 and 2014 was included to analyse the association between disease-free survival (DFS) and overall survival (OS) with RDI (ratio of received to planned dose-intensity). High RDI was defined as cisplatin RDI of > 75% and low RDI ≤ 75%.

RESULTS

Out of 198 patients, 166 were eligible. Low RDI was administered to 72 (43%) patients. In multivariate analysis, those patients had a significantly higher risk of recurrence (HR: 1.87, 95%CI 1.13-3.09, p = 0.01) and death (HR: 1.91, 95%CI 1.32-3.23, p = 0.01) versus patients in the high RDI group. The risk of death was significantly higher in patients with PS 1 treated with low versus high RDI (HR: 2.72, 95%CI: 1.22-6.09, p = 0.014). The risk of recurrence was higher for patients with squamous cell carcinoma of low versus high RDI (HR: 3.82, 95%CI: 1.01-14.4, p = 0.048). No impact of delayed APC beyond six weeks from surgery on neither DFS (HR: 0.78, 95%CI: 0.46-1.33, p = 0.36) nor OS (HR 0.67, 95%CI: 0.40-1.15, p = 0.15) was observed.

CONCLUSION

Low cisplatin RDI ≤ 75% of APC, but not extended time from surgery to APC onset > six weeks, was associated with significantly shorter survival in NSCLC patients.

Internal quality control in an academic cytopathology laboratory for the introduction of a new reporting system for endometrial cytology

BACKGROUND

To evaluate reproducibility of a reporting system for endometrial cytology.

METHODS

Cytologic slides from 49 patients, prepared via liquid based cytology, were blindly examined by five cytopathologists of various experience levels, applying a recently introduced reporting system as previously reported. The agreement among cytopathologists was evaluated via Kappa (κ) statistics and the Kendall's Coefficient of Variation (W); cytologic results were compared with the relevant histologic report.

RESULTS

Substantial agreement among all five raters was found in the benign, ACE-L and malignant categories, fair agreement in inadequate and ACE-H categories, whereas only slight agreement in ACE-U. For the three more experienced cytopathologists, an almost perfect agreement was found in inadequate, benign, and ACE-L categories, substantial agreement in ACE-H and malignant categories and fair agreement in ACE-U category. Overall agreement for all five cytopathologists and for all categories was moderate, whereas it was very high for the three senior raters. Using the Kendall's test, both five cytopathologists (W = 0.81) and the three senior ones (W = 0.93) had very high agreement. Sensitivity: 83.33-92.59%, specificity: 83.33-94.74%, ROC area: 71.72-90.3%.

CONCLUSION

Application of appropriate statistical tests shows that integration of a new reporting cytologic system is effective with an overall accuracy around 90%. Both statistical tests applied disclosed lower agreement rates among both all five raters and the three most experienced ones in the intermediate categories constituting the gray zone, thus delineating the need for better training of cytopathologists to correctly identify diagnostic criteria for classification of a given case into these categories.

Malignant mesothelioma in 91 danish women: The environmental asbestos exposure

8560

Background: Malignant Mesothelioma (MM) is an asbestos-related malignancy that presents mainly in the pleura (MPM) and peritoneum (MAM). In a densely populated area of Aalborg city in North Jutland, Denmark, a large Eternit asbestos factory that was active for 60 years until 1986 and two shipyards were situated. The Region of North Jutland, Denmark has a high mm incidence in women of 1.0/100,000. Methods: From 1974-2015, 101 histological and cytological samples of women diagnosed with mm in Aalborg University Hospital were identified re-evaluated by modern immunohistochemistry. Patient information regarding asbestos exposure was retrieved from medical records and selected Danish registries. Asbestos exposure was classified as primary for asbestos workers; domestic, for women living with an asbestos worker; environmental, when living or working within 10.000 meters from an asbestos emitting location; unknown, where no source of asbestos exposure could be identified. Results: Clinical and histopathological mm diagnosis was certain for 91 women. Potential asbestos exposure is summarized in Table 1. The employment of the women and their relatives include work at the asbestos cement factory, shipyard, construction, laboratory, pipe factory, electrician and insulator. The women with domestic and combined domestic and environmental (secondary) exposure to asbestos were most prone to develop MPM rather than MAM while women primary exposed to asbestos developed MAM rather than MPM (p=0.016). Conclusions: This study showed that the vast majority (64%) of the women diagnosed with mm had documented non-occupational asbestos exposure and almost 1/5 had a sole environmental exposure, by living in proximity to asbestos industry. Environmental asbestos exposure is a serious risk factor for mm in women. Primary asbestos exposure, inferring more intense exposure through occupation, may predispose to peritoneal mesothelioma in women. [Table: see text]

Identification and Functional Characterization of a Calcium-Sensing Receptor Mutation in an Infant with Familial Hypocalciuric Hypercalcemia

Familial hypocalciuric hypercalcemia (FHH) is an autosomal dominant disorder, associated with inactivating mutations of the calcium-sensing receptor (CaSR). To evaluate the functional significance of a CaSR mutation, identified in a young infant who presented with hypercalcemia and hypocalciuria. The CaSR gene coding sequences were analyzed by polymerase chain reaction amplification and direct sequencing analysis. The mutation identified was introduced by site-directed mutagenesis into a wild-type (WT) CaSR plasmid, and human embryonic kidney 293 T cells were transfected with either the WT or mutant CaSR. The function of the mutated CaSR protein was analyzed by evaluating the free intracellular calcium [(Ca2+)i] response after challenge with extracellular calcium (Ca2+). We identified a heterozygous mutation c.772_773delGTinsA in exon 4 resulting in the substitution of amino acid valine (Val) with amino acid arginine (Arg) and the premature pause of the translation 46 amino acids later (Val258ArgfsTer47). Functional assay showed that cells transfected with the mutant CaSR had a significantly poorer response to extracellular Ca2+ stimulation compared with the WT. We have shown that the c.772_773delGTinsA mutation causes a significant alteration of CaSR function leading to features of FHH in an affected young infant since the first months of life.

Functional and immunohistochemical characterization of CCEae3a, a carboxylesterase associated with temephos resistance in the major arbovirus vectors Aedes aegypti and Ae. albopictus

Temephos is a major organophosphate (OP) larvicide that has been used extensively for the control of Aedes albopictus and Aedes aegypti, the major vectors for viral diseases, such as dengue fever, zika and chikungunya. Resistance to temephos has been recently detected and associated with the upregulation of carboxylesterases (CCEs) through gene amplification, in both species. Here, we expressed the CCEae3a genes which showed the most striking up-regulation in resistant Aedes strains, using the baculovirus system. All CCEae3a variants encoded functional enzymes, with high activity and preference for p-nitrophenyl butyrate, a substrate that was shown capable to differentiate temephos resistant from susceptible Aedes larvae. Enzyme kinetic studies showed that CCEae3as from both Ae. aegypti and Ae. albopictus (CCEae3a_aeg and CCEae3a_alb, respectively) strongly interact with temephos oxon and slowly released the OP molecule, indicating a sequestration resistance mechanism. No difference was detected between resistant and susceptible CCEae3a_aeg variants (CCEae3a_aegR and CCEae3a_aegS, respectively), indicating that previously reported polymorphism is unlikely to play a role in temephos resistance. HPLC/MS showed that CCEae3as were able to metabolize temephos oxon to the temephos monoester [(4-hydroxyphenyl) sulfanyl] phenyl O,O-dimethylphosphorothioate. Western blot and immunolocalization studies, based on a specific antibody raised against the CCEae3a_alb showed that the enzyme is expressed at higher levels in resistant insects, primarily in malpighian tubules (MT) and nerve tissues.

Cytopathologic diagnosis of fine needle aspiration biopsies of thyroid nodules

Fine-needle aspiration (FNA) cytology is an important diagnostic tool in patients with thyroid lesions. Several systems have been proposed for the cyropathologic diagnosis of the thyroid nodules. However cases with indeterminate cytological findings still remain a matter of debate. In this review we analyze all literature regarding Thyroid Cytopathology Reporting systems trying to identify the most suitable methodology to use in clinical practice for the preoperative diagnosis of thyroid nodules. A review of the English literature was conducted, and data were analyzed and summarized and integrated from the authors’ perspective. The main purpose of thyroid FNA is to identify patients with higher risk for malignancy, and to prevent unnecessary surgeries for benign conditions. The Bethesda System for Reporting Thyroid Cytopathology is the most widely used system for the diagnosis of thyroid FNA specimens. This system also contains guidelines for the diagnosis and treatment of indeterminate or suspicious for malignancy cases. In conclusion, patients who require repeated FNAs for indeterminate diagnoses will be resolved by repeat FNA in a percentage of 72%-80%.

The key role of bisphosphonates in the supportive care of cancer patients

The present review aims at providing an assessment of the clinical significance of Biphosphonates (BPs) in the treatment of patients with cancer.

MATERIALS AND METHODS

A systematic literature review was performed based on database search in PubMed/Medline and included articles up to August 2013.

RESULTS

BPs can reduce, delay, and prevent complications related to bone metastases. They improve mobility, functionality, pain, and quality of life. They limit survival of any inactive cancer cells in the microenvironment of the bone marrow, contributing to their death from anti-neoplastic treatments. Moreover, they limit and delay bone morbidity due to osteoporosis related to hormonotherapy in breast and prostate cancer. Finally, benefits can be derived from the combination of BPs with radiotherapy in bone density, recalcification, opioid use, and patient's quality of life and performance status.

CONCLUSION

The contribution of BPs in the course of certain neoplasms is preventive and synergistic to other treatments.

Fine needle aspiration cytology of nodular thyroid lesions: a 2-year experience of the Bethesda system for reporting thyroid cytopathology in a large regional and a university hospital, with histological correlation

OBJECTIVE

Thyroid fine needle aspiration (FNA) contributes to the appropriate management of nodular thyroid lesions. The introduced categories in the Bethesda system for reporting thyroid cytopathology (TBSRTC) are associated with an implied cancer risk, providing a clinical management guideline. This study aims to evaluate the reproducibility of this implied risk and to compare the results from two different cytopathology departments.

METHODS

Five hundred histologically confirmed FNAs, studied since the introduction of TBSRTC, were obtained from 4208 and 3587 FNAs performed in a large regional hospital in Herakleion, Crete (group A) and a university hospital in Athens (group B), respectively. Reports were issued according to TBSRTC. Aspirates were prepared with ThinPrep(®) and evaluated by two experienced cytopathologists. The reproducibility and accuracy were evaluated.

RESULTS

The proportion test for suspicious for malignancy (SFM) and malignant (M) cytology reports (P < 0.0001), and the number of malignancies on histology (P < 0.0001), were significantly higher in group A than in group B, consistent with a higher incidence of thyroid carcinomas in southern Greece. Although the malignancy rates were higher in group A than in group B for all categories, except M (A, 99.3%; B, 100%), the difference was only significant for benign aspirates (P = 0.0303). Malignancy rates for all categories in group A were above the TBSRTC recommended range, but were consistent with an increased prevalence of malignancy in that centre, differences in reporting practice and the variable ranges reported in the literature. There was lower sensitivity (P = 0.019) and overall accuracy (P = 0.003) in group A relative to group B, but no difference in specificity.

CONCLUSIONS

TBSRTC provides valuable information for the appropriate management of nodular thyroid lesions, both in a university and a large regional hospital.

mRNA and DNA detection of human papillomaviruses in women of all ages attending two colposcopy clinics

OBJECTIVE

HPV infection is a common finding, especially in young women while the majority of infections are cleared within a short time interval. The aim of this study was to examine the efficacy of HPV DNA and mRNA testing in a population attending colposcopy units of two University hospitals.

METHODS

1173 liquid based cervical samples from two colposcopy clinics were tested for HPV DNA positivity using a commercial typing kit and HPV E6/E7 mRNA positivity with a flow cytometry based commercial kit. Statistic measures were calculated for both molecular tests and morphological cytology and colposcopy diagnosis according to histology results.

RESULTS

HPV DNA, high-risk HPV DNA, HPV16 or 18 DNA and HPV mRNA was detected in 55.5%, 50.6%, 20.1% and 29.7% of the cervical smears respectively. Concordance between the DNA and the mRNA test was 71.6% with their differences being statistically significant. Both tests' positivity increased significantly as lesion grade progressed and both displayed higher positivity rates in samples from women under 30 years old. mRNA testing displayed similar NPV, slightly lower sensitivity but significantly higher specificity and PPV than DNA testing, except only when DNA positivity for either HPV16 or 18 was used.

CONCLUSIONS

Overall mRNA testing displayed higher clinical efficacy than DNA testing, either when used as a reflex test or as an ancillary test combined with morphology. Due to enhanced specificity of mRNA testing and its comparable sensitivity in ages under 25 or 30 years old, induction of mRNA testing in young women could be feasible if a randomized trial verifies these results.

Comparison of two commercially available methods for HPV genotyping: CLART HPV2 and Linear Array HPV Genotyping tests

OBJECTIVE

To compare the clinical efficiency of two commercially available HPV DNA detection and typing tests. The CLART HPV2 test, a novel HPV test based on DNA microarrays that can identify 35 HPV genotypes, was compared to the Linear Array HPV Genotyping (LA) test, a more widely used test able to identify 37 HPV genotypes.

STUDY DESIGN

The CLART test was evaluated by comparing the genotyping results of 538 ThinPrep Pap tests with the LA test as well as with the cytological and histological findings.

RESULTS

The exact same types and results were identified in 86.1% of the samples (kappa = 0.74). The tests showed excellent agreement in HPV positivity and identification of single and multiple infections (concordance rate 88.7%, kappa = 0.827).

CONCLUSION

The CLART test demonstrated results comparable to those of the LA test in clinical sensitivity as measured by the positive predictive value of CIN2+ in ASCUS (67.3% vs. 57.1%), while overall it exhibited higher sensitivity, specificity, positive and negative predictive values and area under curves than the LA test in all cytological and histological subgroups analyzed.

Cascaded learning vector quantizer neural networks for the discrimination of thyroid lesions

OBJECTIVE

To investigate capability of combination of learning vector quantizer (LVQ) neural networks (NNs) in discrimination of benign from malignant thyroid lesions.

STUDY DESIGN

The study included 335 liquid-based cytology, fine needle aspiration (FNA), Papanicolaou-stained specimens. All cases were compared to the histologic diagnosis. Features describing size, shape, and texture of -100 nuclei per case were extracted from cytologic images using a custom image analysis system. These features were used to classify each nucleus by LVQ type NNs. The nucleus classification results were used to classify individual lesions with a second LVQ NN. Cases were distributed by histologic diagnosis. Data from -50% from each category were used for training LVQ classifiers. Remaining data were used to test classifier performance. The system was used to discriminate to individual cellular level and individual patient level between benign and malignant nuclei.

RESULTS

Application of the proposed algorithm combining two LVQ NNs allows discrimination between benign and malignant cell nuclei and lesions.

CONCLUSION

Results indicate that use of NNs, combined with image morphometry, can provide information on thyroid lesion malignancy potential. The system could improve FNA diagnostic accuracy of the thyroid gland, especially in follicular neoplasms suspicious for malignancy and in Hürthle cell tumors.

A preliminary study of the potential of tree classifiers in triage of high-grade squamous intraepithelial lesions

OBJECTIVE

To investigate the potential value of tree classifiers for the triage of high-grade squamous intraepithelial lesions.

STUDY DESIGN

The dataset comprised 808 histologically confirmed cases having a complete range of the cytologic sample assessments--liquid-based cytology, reflex human papillomavirus (HPV) DNA test, E6/E7 HPV mRNA test, and p16 immunocytochemical examinations. Data include 488 histologically negative (cervical intraepithelial neoplasia [CIN] 1 and below) or clinically negative cases and 320 with histologic diagnosis of CIN 2 or worse. Cytologic diagnosis was made according to the criteria of the Bethesda System. Cases were classified in two groups according to histology: those with CIN 2 or worse and those with CIN 1 and below. Fifty percent were randomly selected as a training set and the remaining were as a test set.

RESULTS

Application of tree classifier on the test set gave correct classification of 66.9% for CIN 2 and above cases and 97.3% for CIN 1 and below, producing overall accuracy of 91.5%, outperforming cytologic diagnosis alone.

CONCLUSION

Application of tree classifiers, based on standard cytologic diagnosis and expression of studied biomarkers, produces improved classification results for cervical precancerous lesions and cancer diagnosis and