Factors influencing blood tumor marker concentrations in the absence of neoplasia.

BACKGROUND: Tumor markers (TMs) are a heterogeneous group of molecules used in the diagnosis, prognosis and follow-up of cancer patients. During neoplastic differentiation, cells can either directly synthesize or induce the synthesis of TMs, and the release of these molecules into the bloodstream allows their quantification in biological fluids. Although very small concentrations of TMs are usually present in the serum or plasma of healthy subjects, increased concentrations may also be found in the presence of benign diseases or due to technical interference, producing false positive results. MATERIAL AND METHODS AND RESULTS: Our review analyses the causes of false positives described between January 1970 to February 2023 for the TMs most frequently used in clinical practice: α-fetoprotein (AFP), ß2-microglobulin (ß2-M), cancer antigen 15-3 (CA 15-3), cancer antigen CA 19-9 (CA 19-9), cancer antigen CA 72-4 (CA 72-4), cancer antigen 125 (CA 125), carcinoembryonic antigen (CEA), chromogranin A (CgA), choriogonadotropin (hCG), cytokeratin 19 fragment (CYFRA 21-1), neuron-specific enolase (NSE), human epididymis protein 4 (HE4), serum HER2 (sHER2), squamous cell carcinoma antigen (SCCA), protein induced by vitamin K absence-II (PIVKA-II), Pro-gastrin-releasing peptide (Pro-GRP), prostate-specific antigen (PSA), Protein S-100 (S-100) and thyroglobulin (Tg). A total of 247 references were included. CONCLUSIONS: A better understanding of pathophysiological processes and other conditions that affect the concentration of TMs might improve the interpretation of results and their clinical application.

Variations in tumor growth, intra-individual biological variability, and the interpretation of changes.

OBJECTIVES: The identification of changes in tumor markers (TMs) in cancer patients that indicate response to treatment, stabilization or disease progression is a challenge for laboratory medicine. Several approaches have been proposed: assessing percentage increases, applying discriminant values, and estimating half-life (t1/2) or doubling time (DT). In all of them it is assumed that the TM is a surrogate of the variation in tumor size. In general this variation is time-dependent, but this is not the case of intraindividual biological variability (CVi), which can range from 6 % in CA15-3 to 22 % in CA125. When decisions are made on the basis of DT or t1/2, these values can be affected by the CVi; if it is very large, the growth rate very slow and the period of time between determinations very short, the result obtained for DT may be due mainly to the CVi. The aim of this study is to establish the relationship between the CVi and temporal variables. METHODS: We related equations for calculating DT and t1/2 to the reference change values in tumor markers. RESULTS: The application of the formula obtained allows the calculation of the optimal time between measurements to ensure that the influence of the CVi is minimal in different types of tumors and different scenarios. CONCLUSIONS: Intraindividual variation affects the calculation of DT and t1/2. It is necessary to establish the minimum time between two measurements to ensure that the CVi does not affect their calculation or lead to misinterpretation.

Lung cancer tumor markers in serous effusions and other body fluids.

From its onset and during its progression, lung cancer may affect various extrapulmonary structures. These include the serous membranes, the pleura and pericardium, and less frequently the central nervous system, with leptomeningeal involvement. In these cases, fluid accumulates in the serous membranes which may contain substances secreted by the tumor. Measuring the concentrations of these substances can provide useful information for elucidating the origin of the fluid accumulation, either in pleural and pericardial effusions or in cerebrospinal fluid. This paper describes the histological types of lung cancer that most frequently affect the serosa and leptomeninges. It also reviews the literature on tumor markers in different fluids and makes recommendations for their interpretation.

Comparative study of obstetric antiphospholipid syndrome (OAPS) and non-criteria obstetric APS (NC-OAPS): report of 1640 cases from the EUROAPS registry.

OBJECTIVES: To compare clinical features, laboratory data and fetal-maternal outcomes between 1000 women with obstetric APS (OAPS) and 640 with aPL-related obstetric complications not fulfilling Sydney criteria (non-criteria OAPS, NC-OAPS). METHODS: This was a retrospective and prospective multicentre study from the European Registry on Obstetric Antiphospholipid Syndrome. RESULTS: A total of 1650 women with 5251 episodes, 3601 of which were historical and 1650 latest episodes, were included. Altogether, 1000 cases (OAPS group) fulfilled the Sydney classification criteria and 650 (NC-OAPS group) did not. Ten NC-OAPS cases were excluded for presenting thrombosis during follow-up. All cases were classified as category I (triple positivity or double positivity for aPL) or category II (simple positivity). Overall, aPL laboratory categories showed significant differences: 29.20% in OAPS vs 17.96% in NC-OAPS (P < 0.0001) for category I, and 70.8% in OAPS vs 82% in NC-OAPS (P < 0.0001) for category II. Significant differences were observed when current obstetric complications were compared (P < 0.001). However, major differences between groups were not observed in treatment rates, livebirths and thrombotic complications. In the NC-OAPS group, 176/640 (27.5%) did not fulfil Sydney clinical criteria (subgroup A), 175/640 (27.34%) had a low titre and/or non-persistent aPL positivity but did meet the clinical criteria (subgroup B) and 289/640 (45.15%) had a high aPL titre but did not fulfil Sydney clinical criteria (subgroup C). CONCLUSION: Significant clinical and laboratory differences were found between groups. Fetal-maternal outcomes were similar in both groups when treated. These results suggest that we could improve our clinical practice with better understanding of NC-OAPS patients.

Cardiac performance after an endurance open water swimming race.

PURPOSE: Endurance exercise competitions have shown a transient negative effect on global right ventricular (RV) performance. Most published studies are based on terrestrial sports. The aim of our study was to evaluate the cardiac effects after an open water swimming race. METHODS: We evaluated 33 healthy swimmers (mean age 40.9 ± 7.2) participating in a 9.5 km open water swimming race. All subjects underwent a standard transthoracic echocardiography including an evaluation of dimensions and myocardial ventricular deformation. Echocardiography was performed 24 h before and within the first hour of arrival at the finish line. Cardiac troponin I (cTn I), NT-ProBNP and leukocytes were also evaluated. RESULTS: No changes in left ventricle (LV) ejection fraction or LV global longitudinal strain were observed. A significant increase in RV end-diastolic area (RVEDA) was noted after the race (RVEDA at baseline 15.12 ± 1.86; RVEDA after race 16.06 ± 2.27, p < 0.05), but no changes were seen in RV fractional area change or RV global longitudinal strain. Cardiac biomarkers and leukocytes significantly increased. No association was detected between the increase in cTn I or NT-proBNP and the RV acute dilatation or LV performance. A significant association was observed between cTn I and leukocytes (r = 0.375, p < 0.05). CONCLUSIONS: An acute RV dilatation but without an impairment in RV deformation was observed after participating in an endurance swimming race. The correlation between the increase in cTn I and leukocytes, but not with ventricular performance, may support the hypothesis of an exercise-induced increase in myocardial sarcolemmal permeability due to an inflammatory response rather than myocardial injury.

Evaluation of two strategies for the interpretation of tumour markers in pleural effusions.

BACKGROUND: Pleural effusions present a diagnostic challenge. Approximately 20% are associated with cancer and some 50% require invasive procedures to perform diagnosis. Determination of tumour markers may help to identify patients with malignant effusions. Two strategies are used to obtain high specificity in the differential diagnosis of malignant pleural effusions: a) high cut-off, and b) fluid/serum (F/S) ratio and low cut-off. The aim of this study is to compare these two strategies and to establish whether the identification of possible false positives using benign biomarkers - ADA, CRP and % of polymorphonuclear cells - improves diagnostic accuracy. METHODS: We studied 402 pleural effusions, 122 of them malignant. Benign biomarkers were determined in pleural fluid, and CEA, CA72-4, CA19-9 and CA15-3 in pleural fluid and serum. RESULTS: Establishing a cut-off value for each TM for a specificity of 100%, a joint sensitivity of 66.5% was obtained. With the F/S strategy and low cut-off points, sensitivity was 77% and specificity 98.2%, Subclassifying cases with negative benign biomarkers, both strategies achieved a specificity of 100%; sensitivity was 69.9% for single determination and 80.6% for F/S ratio. CONCLUSIONS: The best interpretation of TM in the differential diagnosis of malignant pleural effusions is obtained using the F/S ratio in the group with negative benign biomarkers.

Clinical utility of determining tumor markers in patients with signs and symptoms of cancer.

BACKGROUND: Diagnosing patients with signs or symptoms suggestive of cancer is difficult. Serum tumor markers (TM) may be useful, but it is known that a range of pathologies other than cancer can increase their concentrations and so TM data must be interpreted with caution. The aim of this study is to determine the diagnostic accuracy of TMs in patients with signs or symptoms of cancer. METHODS: We prospectively studied 234 patients seen at rapid diagnostic units who presented signs or symptoms suggestive of cancer. Ninety patients had wasting syndrome, 74 had pulmonary symptoms and 70 other presentations. CYFRA21-1, CEA, CA19-9, total bilirubin and creatinine were determined. The final diagnosis was obtained after 6 months' follow-up. Patients were classified according to the absence (group A) or presence (group B) of abnormal bilirubin or creatinine. RESULTS: Of the 234 patients studied, 103 (44.0%) had tumors diagnosed. Cut-off points for each TM were calculated for a specificity of 100%. For the total group, the values were CYFRA21-1, 15 µg/L, CEA, 43.8 µg/L and CA19-9, 7428 KU/L, with an overall sensitivity of 46.6%. For group A (n=142), the following cut-off points were established: CYFRA21-1, 7.8 µg/L, CEA, 13.8 µg/L and CA19-9, 101 KU/L, obtaining a sensitivity of 68.6%. For group B (n=92), the values were the same as for the whole group, and a sensitivity of 42.4% was achieved. CONCLUSIONS: We conclude that TMs can aid diagnosis in these patients with signs or symptoms suggestive of cancer. Their sensitivity can be improved by using different cut-off points in the presence and absence of renal and hepatic dysfunction.

Pituitary-Adrenal Axis and Peripheral Immune Cell Profile in Long COVID.

In Long COVID, dysfunction in the pituitary-adrenal axis and alterations in immune cells and inflammatory status are warned against. We performed a prospective study in a cohort of 42 patients who suffered COVID-19 at least 6 months before attending the Long COVID unit at Althaia Hospital. Based on Post-COVID Functional Status, 29 patients were diagnosed with Long COVID, while 13 were deemed as recovered. The hormones of the pituitary-adrenal axis, adrenocorticotropin stimulation test, and immune cell profiles and inflammatory markers were examined. Patients with Long COVID had significantly lower EuroQol and higher mMRC scores compared to the recovered individuals. Their symptoms included fatigue, myalgia, arthralgia, persistent coughing, a persistent sore throat, dyspnoea, a lack of concentration, and anxiety. We observed the physiological levels of cortisol and adrenocorticotropin in individuals with or without Long COVID. The results of the adrenocorticotropin stimulation test were similar between both groups. The absolute number of neutrophils was lower in the Long COVID patients compared to recovered individuals (p < 0.05). The total count of B lymphocytes remained consistent, but Long COVID patients had a higher percentage of mature B cells compared to recovered participants (p < 0.05) and exhibited a higher percentage of circulating resident memory CD8+ T cells (p < 0.05) and Treg-expressing exonucleases (p < 0.05). Our findings did not identify adrenal dysfunction related to Long COVID, nor an association between adrenal function and clinical symptoms. The data indicated a dysregulation in certain immune cells, pointing to immune activation. No overt hyperinflammation was observed in the Long COVID group.

Randomized clinical trial to evaluate the effect of a supervised exercise training program on readmissions in patients with myocardial ischemia: a study protocol.

BACKGROUND: In recent decades, several studies have assessed the value of cardiac rehabilitation as secondary prevention and have reported substantial reductions in readmissions. However, conclusive evidence is scarce. The present study aims to evaluate the efficacy of a supervised exercise training program for improving percentages of hospital readmission for cardiac causes in patients with myocardial ischemia in the first year after a cardiac event. The effect on all-cause readmission, all-cause mortality, functional capacity, quality of life and adherence to regular exercise is also discussed. METHODS/DESIGN: This study will be conducted as a randomized controlled trial. Eligible patients will be randomly assigned to a control group receiving standard care or to an intervention group which, in addition to standard care, will take part in a supervised exercise training program consisting of three hours a week (spread over three alternate days) of supervised exercise training for 10 weeks. Both groups will perform an exercise stress test and a blood test during the first and third month after hospital discharge. The follow-up period will be 12 months after hospital discharge. The primary outcome measures will be the percentage of patients readmitted, total number of readmissions and length of hospitalization for cardiac disease during the first year after hospital discharge, and time to first hospital admission for cardiac disease. DISCUSSION: A representative group of hospitalized patients after myocardial ischemia will be studied in order to provide comprehensive data on the potential impact of a supervised exercise training program on hospital readmission rates. TRIAL REGISTRATION: Current Controlled Trials ISRCTN57634424.

Thrombosis and Hyperinflammation in COVID-19 Acute Phase Are Related to Anti-Phosphatidylserine and Anti-Phosphatidylinositol Antibody Positivity.

Antiphospholipid antibodies (APLA) are strongly associated with thrombosis seen in patients with antiphospholipid syndrome. In COVID-19, thrombosis has been observed as one of the main comorbidities. In patients hospitalised for COVID-19, we want to check whether APLA positivity is associated with COVID-19-related thrombosis, inflammation, severity of disease, or long COVID-19. We enrolled 92 hospitalised patients with COVID-19 between March and April 2020 who were tested for 18 different APLAs (IgG and IgM) with a single line-immunoassay test. A total of 30 healthy blood donors were used to set the cut-off for each APLA positivity. Of the 92 COVID-19 inpatients, 30 (32.61%; 95% CI [23.41-43.29]) tested positive for APLA, of whom 10 (33.3%; 95% CI [17.94-52.86]) had more than one APLA positivity. Anti-phosphatidylserine IgM positivity was described in 5.4% of inpatients (n = 5) and was associated with the occurrence of COVID-19-related thrombosis (p = 0.046). Anti-cardiolipin IgM positivity was the most prevalent among the inpatients (n = 12, 13.0%) and was associated with a recorded thrombosis in their clinical history (p = 0.044); however, its positivity was not associated with the occurrence of thrombosis during their hospitalisation for COVID-19. Anti-phosphatidylinositol IgM positivity, with a prevalence of 5.4% (n = 5), was associated with higher levels of interleukin (IL)-6 (p = 0.007) and ferritin (p = 0.034). Neither of these APLA positivities was a risk factor for COVID-19 severity or a predictive marker for long COVID-19. In conclusion, almost a third of COVID-19 inpatients tested positive for at least one APLA. Anti-phosphatidylserine positivity in IgM class was associated with thrombosis, and anti-phosphatidylinositol positivity in IgM class was associated with inflammation, as noticed by elevated levels of IL-6. Thus, testing for non-criteria APLA to assess the risk of clinical complications in hospitalised COVID-19 patients might be beneficial. However, they were not related to disease severity or long COVID-19.

A new approach to prostate cancer screening.

Prostate cancer screening based on prostate-specific antigen (PSA) testing has been a matter of controversy. Although screening for prostate cancer was effective in reducing mortality, it resulted in overdiagnosis, which translated into unnecessary treatments and numerous adverse effects. As a result, recommendations from scientific societies became increasingly restrictive. In the recent years, new approaches to prostate cancer screening have been proposed. These new approaches are aimed at solving the controversy between widespread screening vs. no screening, and reconsidering PSA testing as a screening tool with a good benefit/risk balance. In this context, the European Association of Urology submitted a proposal to the European Commission for prostate cancer screening to be performed as a function of baseline PSA concentrations. The European Commission recently recommended the implementation of organized prostate cancer screening programs for men aged ≤70 years based on PSA values in combination with follow-up magnetic resonance imaging.

Utility of human epididymis protein 4 in the differential diagnosis of ascites.

BACKGROUND AND AIMS: Human epididymal protein 4 (HE4) may be a useful tool in the differential diagnosis of malignant ascites. The aim of this study was to evaluate the diagnostic utility of HE4 for detecting malignant ascites, taking into account the possible false positives identified with adenosine deaminase (ADA), C-reactive protein (CRP), % polynuclear cells (%PMN) and glomerular filtration rate (eGFR). METHODS: Concentrations of HE4, ADA, %PMN and CRP were determined in 114 samples of peritoneal fluid and creatinine in serum in order to calculate eGFR. RESULTS: Concentrations of HE4 presented significant differences (P = 0.028) in benign [median (interquartile range)] [582(372)] pmol/L) and malignant ascites ([8241(367)] pmol/L. Sensitivity was 21.2% and specificity 100%. Significant differences were also observed for HE4 between tumors of gynecological origin ([3165(8769)] pmol/L) and others ([665(663)] pmol/L), with a sensitivity of 67% and a specificity of 100%. Classifying according to possible false positives (ADA > 45U/L, CRP > 50 mg/L, %PMN > 90 and eGFR < 30 mL/min/1.73 m2) at maximum specificity, a sensitivity of 33.3% was obtained for HE4, with a cut-off point of 2660 pmol/L. Without possible false positives (ADA < 45U/L, CRP < 50 mg/L, %PMN < 90 and eGFR ≥ 30 mL/min/1.73 m2), a sensitivity of 37.7% was obtained at 100% specificity for a cut-off point of 1041 pmol/L. Applying these criteria to the entire group, a sensitivity of 36.4% was obtained at maximum specificity. CONCLUSIONS: HE4 allows the identification of malignant ascites with moderate sensitivity at maximum specificity. HE4 levels can differentiate between tumors of gynecological origin and others. Classification according to possible false positives increases sensitivity without losing specificity.

Diagnostic accuracy of tumour markers in serous effusions: a validation study.

The utility of tumour markers (TM) in the differential diagnosis of cancer in serous effusion (fluid effusion (FE)) has been the subject of controversy. The aim of this study was to prospectively validate our previous study and to assess whether the addition of adenosine deaminase (ADA), C-reactive protein (CRP) or percentage of polymorphonuclear cells (%PN) allows the identification of false positives. In this study, carcinoembryonic antigen, cancer antigen 15-3, cancer antigen 19-9, ADA, CRP and %PN in FE were determined in 347 patients with 391 effusions. Effusions were considered as malignant effusion when at least one TM in serum exceeded the cutoff and the ratio FE/S was higher than 1.2. Also, cases with values of ADA, CRP and %PN above the established cutoffs in serous effusion were considered as potential false positives. The combined sensitivity and specificity of the three TM was 76.2 % (95 % confidence intervals (CI) 67.8-83.3 %) and 97.0 % (95 % CI 94.1-98.7), respectively. Subanalysis of the 318 cases with previous criteria and negative ADA, CRP and %PN obtained sensitivities of 78.4 % (95 % CI 69.4-85.6) and a specificity of 100 % (95 % CI 98.2-100). The results obtained validate our previous study and are improved with the addition of ADA, CRP and %PN. TM in serous effusions and serum could be useful for the diagnostic assessment of patients with serous effusions.

Determination of the biological variation of S100ß and lactate dehydrogenase in disease-free patients with malignant melanoma.

BACKGROUND: Biological variation is important for determining analytical goals and for establishing the magnitude of change between two consecutive measurements. The aim of this study was to determine the biological variation for S100ß and lactate dehydrogenase in patients diagnosed with malignant melanoma but without evidence of disease recurrence. METHODS: The biological variation of S100ß and lactate dehydrogenase was estimated from a mean of four consecutive measurements in 32 patients diagnosed with malignant melanoma but without evidence of disease recurrence, 3 months after tumor resection or 4 months after finishing adjuvant treatment. The mean sampling interval was 3 months. RESULTS: Mean concentrations of S100ß and lactate dehydrogenase were 0.0557 µg/L and 6.3 µkat/L, respectively. Between-run analytical variation was 3.5% at 0.181 µg/L for S100ß and 3.5% at 2.83 µkat/L for lactate dehydrogenase. Biological variations obtained for S100ß and lactate dehydrogenase were 14.2% and 8.2%, respectively. The analytical goals (defined as 50% of biological variation) were 7.1% for S100ß and 4.1% for lactate dehydrogenase. CONCLUSIONS: The estimation of biological variation allows us to calculate analytical goals and reference change values. These are necessary tools for the correct interpretation of serial measurements in patient follow-up.

Increased plasma concentrations of tumour markers in the absence of neoplasia.

Tumour markers are a very heterogeneous group of molecules that are generally found in very small concentrations in the plasma and serum of healthy individuals. In the process of neoplastic differentiation the cell can synthesize, release, or induce synthesis of other cells, thus increasing their concentration in plasma and serum. These substances may also increase their plasma concentration in patients without cancer due to processes that increase the release or reduce catabolism, and so give rise to false positives. An understanding of the main physiopathological processes that increase the concentrations of these substances could improve our interpretation of tumour markers and their clinical application. In this study we review the physiopathological processes that may increase the plasma concentrations of tumour markers. We performed a bibliography review in PubMed, searching for causes of false positives for the following tumour markers: α-Fetoprotein, CA 125, CA 15-3, CA 19-9, CA 72-4, carcinoembryonic antigen, CYFRA 21-1, squamous cell carcinoma, prostatic specific antigen, ß(2)-microglobulin, choriogonadotropin (ß chain), chromogranin A, neuron specific enolase, HER2-neu, progastrin releasing peptide, S-100, and thyroglobulin. The results favour the use of tests which can identify pathological processes that may increase tumour marker concentrations.

Lupus anticoagulant is an independent risk factor for non-thrombotic in-hospital mortality in COVID-19 patients.

BACKGROUND: Thromboembolic disease is a frequent cause of death during SARS CoV-2 infection. Lupus anticoagulant (LA) appears frequently during the acute phase of infection. It is not clear whether it is merely an epiphenomenon or whether it is related to the patients' outcome. METHODS: Prospective observational cohort of 211 patients (118 women, mean age 65 years, range: 18 to 99) hospitalized for COVID-19. All patients were tested for LA at admission and retested six months after discharge. RESULTS: The LA test was positive in 128 patients (60.7%). The survival probability at 31 days was clearly worse in the LA-positive group (60%) than in the LA-negative group (90%) (P = 0.023). This notable difference in survival was confirmed by multivariate analysis (HR 3.9, 95% CI 1.04-14.5, P = 0.04). However, it was not explained by differences in thrombotic events (three in either group, P = 0.6). LA-positive patients had higher ferritin, CRP and IL-6 levels, and lower PAFI ratio and lymphocyte and platelet counts. Six months after discharge, LA was negative in the vast majority of positive cases (94%). CONCLUSION: LA is an independent predictor of in-hospital mortality in COVID-19 patients. It is associated with inflammation and disease severity but not with thromboembolic events. This marker usually disappears at six months.

Etiologies and 12-month mortality in patients with isolated involuntary weight loss at a rapid diagnostic unit.

BACKGROUND: Numerous studies on involuntary weight loss (IWL) have been published since the 1980s, although most of them have included small samples of patients with specific symptoms. The aim of the present study was to determine the causes, demographic and clinical characteristics and mortality at 12 months in patients attended at a rapid diagnostic unit (RDU) for isolated IWL. METHODS: A single-center retrospective observational study including all patients presenting to the RDU for isolated IWL between 2005 and 2013. The following data were recorded: demographic and clinical variables, results of complementary tests (blood tests, x-rays, computed tomography scan and digestive endoscopy), main diagnosis and vital status at 12 months. RESULTS: Seven hundred and ninety-one patients met the criteria for IWL. Mean age was 67.9 years (SD 4.7), 50.4% were male and mean weight loss was 8.3 kg (SD 4.7). The cause for IWL was malignant disease in 23.6% of patients, non-malignant organic disease in 44.5%, psychiatric disorder in 29.0% and unknown in 3.2%. Overall mortality at 12 months was 18.6% (95%CI: 16.1-21.6). The mortality rate was highest in the group with malignancy (61.1%; 95%CI: 54.2-68.2). CONCLUSIONS: Almost a quarter of all patients attended at the RDU for IWL were diagnosed with cancer. Mortality at 12 months was higher in this group than in the other three. Malignancy should therefore be ruled out during the first visit for patients attended for IWL.

Tumour Markers in the Differential Diagnosis of Patients With Isolated Involuntary Weight Loss.

BACKGROUND/AIM: Paraneoplastic syndrome symptoms include isolated involuntary weight loss (IIWL). The differential diagnosis of cancer from other diseases may require a significant number of tests. Tumour markers (TMs) can be used for the diagnosis and stratification of patients according to cancer risk. PATIENTS AND METHODS: This study included 606 patients (48% females) seen at the rapid diagnostic unit for IIWL. We determined the levels of TMs carcinoembryonic antigen, carbohydrate antigen 19-9, soluble fragments of cytokeratin 19, carbohydrate antigen 15-3, carbohydrate antigen 125, neuron specific enolase, alpha-fetoprotein, prostatic specific antigen using the multiparametric analyser COBAS 601. Two cut-off points were established, the upper reference limit described by the manufacturer and a high cut-off point suggested by Molina et al., to stratify patients according to cancer risk. RESULTS: Patients were classified according to TM levels as follows: I) all TMs below the upper reference limit; II) highest number of TMs between the two cut-offs; III) at least one TM above the higher cut-off. The odds ratio for malignancy was 4.3 for group II and 248 for group III. These results indicate that when at least one TM is above the higher cut-off, neoplasia is highly probable. CONCLUSION: TM determination allowed to establish cancer risk in patients with IIWL.

Previous SARS-CoV-2 Infection Increases B.1.1.7 Cross-Neutralization by Vaccinated Individuals.

With the spread of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is a need to assess the protection conferred by both previous infections and current vaccination. Here we tested the neutralizing activity of infected and/or vaccinated individuals against pseudoviruses expressing the spike of the original SARS-CoV-2 isolate Wuhan-Hu-1 (WH1), the D614G mutant and the B.1.1.7 variant. Our data show that parameters of natural infection (time from infection and nature of the infecting variant) determined cross-neutralization. Uninfected vaccinees showed a small reduction in neutralization against the B.1.1.7 variant compared to both the WH1 strain and the D614G mutant. Interestingly, upon vaccination, previously infected individuals developed more robust neutralizing responses against B.1.1.7, suggesting that vaccines can boost the neutralization breadth conferred by natural infection.