To investigate the correlations between metabolic parameters (MPs) of 18 F-fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography (PET/CT), serum tumor markers (STMs), and tumor mutational burden (TMB) in patients with non-small cell lung cancer (NSCLC).
In this retrospective study, we enrolled 129 patients with NSCLC (males, 78; females, 51) who underwent baseline TMB and STM tests and 18 F-FDG PET/CT scans before treatment between March 2018 and September 2022. Patients were categorized into TMB-high (TMB ≥10 mutations/Mb; n = 27 [20.9%]) and non-TMB-high (TMB <10 mutations/Mb; n = 102 [79.1%]) groups. Binary logistic regression analyses were performed to determine independent predictors of TMB-high. Univariate and multivariate linear regression analyses were performed to determine independent predictors of TMB level on a log scale. Subgroup analyses for adenocarcinoma (ADC), ADC with EGFR+, ADC with EGFR-, and squamous cell carcinoma (SCC) were performed.
For ADC, all MPs (SULpeak , SULmax , SULmean , MTV, and TLG) were significantly higher in the TMB-high group than the non-TMB-high group; smoker (odds ratio [OR] = 27.08, p = 0.018), EGFR+ (OR = 0.03, p = 0.033), KRAS+ (OR = 7.98, p = 0.083), high CEA (OR = 33.56, p = 0.029), and high CA125 (OR = 13.68, p = 0.030) were independent predictors of TMB-high; and all MPs showed significant positive linear correlations with TMB on a log scale, with SULpeak as an independent predictor. However, no significant correlation was observed for SCC.
MPs and STMs can predict the TMB level for patients with ADC, and may serve as potential substitutes for TMB with increased value and easy implementation in guiding immunotherapy through noninvasive methods.

Metastatic germ cell tumors of the testis (GCTs) are risk-stratified according to the International Germ Cell Cancer Collaborative Group (IGCCCG) classification system. This risk classification is based on anatomical risk factors as well as tumor marker levels of AFP, HCG, and LDH assessed pre-chemotherapy after orchiectomy treatment. An incorrect classification is possible when pre-orchiectomy marker levels are used, possibly resulting in over- or undertreatment of patients. The aim was to investigate the potential frequency and clinical relevance of incorrect risk stratification using pre-orchiectomy tumor marker levels.
A multicenter registry analysis, including patients with metastasized nonseminomatous GCT (NSGCT), was conducted by investigators of the German Testicular Cancer Study Group (GTCSG). Based on the marker levels at different timepoints, IGCCCG risk groups were calculated. The agreement was tested using Cohen\'s kappa.
A total of 672 of 1910 (35%) patients were diagnosed with metastatic NSGCTs, and 523 (78%) had sufficient data for 224 follow-up data points. By using pre-orchiectomy tumor marker levels, 106 patients (20%) would have been incorrectly classified. Seventy-two patients (14%) were classified into a higher risk category, and 34 patients (7%) were classified into a lower risk category. Cohen\'s kappa was 0.69 (p < 0.001), showing a strong agreement between the use of both marker timepoints. The treatment of misclassified patients would have resulted in an overtreatment of 72 patients or undertreatment of 34 patients.
The use of pre-orchiectomy tumor marker levels may lead to an incorrect risk classification and might subsequently lead to under- or overtreatment of patients.

S100 protein is routinely used as a serum tumor marker in advanced cutaneous melanoma. However, there is scarce and inconclusive evidence on its value in monitoring disease progression of uveal melanoma. In this monocenter study, we retrospectively assessed the connection between documented S100 protein levels of patients suffering from stage IV uveal melanoma and the clinical course of disease. Where available, we analyzed expression of S100 in melanoma metastases by immunohistochemistry. A total of 101 patients were included, 98 had available serum S100 levels, and in 83 cases, sufficient data were available to assess a potential link of S100 with the clinical course of the uveal melanoma. Only 12 of 58 (20.7%) patients had elevated serum levels at first diagnosis of stage IV disease. During progressive disease, 54% of patients showed rising serum S100 levels, while 46% of patients did not. Tumor material of 56 patients was stained for S100. Here, 26 (46.4%) showed expression, 19 (33.9%) weak expression, and 11 (19.6%) no expression of S100. Serum S100 levels rose invariably in all patients with strong expression throughout the course of disease, while patients without S100 expression in metastases never showed rising S100 levels. Thus, the value of S100 serum levels in monitoring disease progression can be predicted by immunohistochemistry of metastases. It is not a reliable marker for early detection of advanced disease.

Primary cutaneous mucinous carcinoma (PCMC) is a rare malignant skin adnexal tumor. Recurrences are most often localized, and long-term follow-up after complete surgery consists essentially of self-examination of skin. We report one case of metastatic PCMC with elevated levels of serum CEA and CA15.3. Because of the difficulty to differentiate PCMC and metastasis of mucinous breast cancer, the hypothesis of a metastasized breast cancer was ruled out. These tumor markers contributed to the monitoring of the metastatic disease. Since metastatic disease was diagnosed after several years of seeming complete remission, CEA and CA15.3 would likely have allowed the clinicians to detect the relapse earlier. Although the use of tumor biomarkers in PCMC is not rooted in clinical practice and not mentioned in guidelines, we suggest that CEA and CA15.3 could be of particular interest to monitor and detect early metastatic PCMC.

Biomarkers play a key role in patients with testicular germ cell tumors in a variety of clinical contexts, including initial diagnosis, prognostication, monitoring treatment response, and posttreatment surveillance. Although the classic serum tumor markers for testicular germ cell tumors are essential for clinical management, the low sensitivity (particularly for seminoma and teratoma) and potential for false positives has spurred novel biomarker discovery and validation efforts. Here, we review the current state of serum-based biomarkers for testicular germ cell tumors, with a focus on the classic serum tumor markers and emerging class of microRNA markers.

Plasma and tissue biopsy have both used for targeting actionable driver gene mutations in lung cancer, whose concordance is imperfect. A reliable method to predict the concordance is urgently needed to ease clinical application.
A total of 1012 plasma samples, including 519 with paired-tissue biopsy samples, derived from lung adenocarcinoma patients were retrospectively enrolled. We assessed the associations of several clinicopathological characteristics and serum tumor markers with the concordance between plasma and tissue biopsies.
When carcinoembryonic antigen (CEA) levels were higher than thresholds of 15.01 ng/ml and 51.15 ng/ml, the positive predictive value of concordance reached 90% and 95%, respectively. When CEA levels were lower than thresholds of 5.19 ng/ml and 3.26 ng/mL, the negative predictive value of concordance reached 45% and 50%. The performance of CYFRA21-1 in predicting concordance was similar but inferior to CEA (AUC: 0.727 vs. 0.741, p = 0.633). The performance of CEA combined with CYFRA21-1 in predicting the concordance was similar to that of the combination of independent factors derived from the LASSO regression model (AUC: 0.796 vs. 0.818, p = 0.067). CEA (r = 0.47, p < 0.01) and CYFRA21-1 levels (r = 0.45, p < 0.05) were significantly correlated with the maximum variant allele frequency, respectively.
CEA combined with CYFRA21-1 could effectively predict the concordance between plasma and tissue biopsies, which could be used for evaluating the priority of plasma and tissue biopsies for gene testing to timely guide clinical applications in advanced lung adenocarcinoma patients.

UNASSIGNED: Gastric cancer (GC) is one of the most common malignant tumors in humans. Carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, and CA72-4 are all serum tumor markers for diagnosis of gastric cancer. However, the results of studies reporting the diagnosis of the combined three varied. In this study, the combined diagnostic performance of these 3 serum tumor markers was systematically evaluated.
UNASSIGNED: PubMed, Embase, The Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang data were searched for literature on serum tumor markers CEA, CA19-9, and CA72-4 in the diagnosis of gastric cancer. The inclusion criteria were designed according to the Participants, Intervention, Control, Outcomes, Study (PICOS) principles. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS) scoring scale was used to assess the quality of the literature. After extracting the data, Stata 16.0 software was used for meta-analysis.
UNASSIGNED: A total of 10 articles were finally included, and a total of 6,574 patients participated in diagnosis, 3,077 for confirmed GC and 3,497 for non-GC respectively. Meta-analysis results showed that the diagnostic sensitivity of the combined diagnosis of the 3 tumor markers was 0.67 [95% confidence interval (CI): 0.54, 0.77], the specificity was 0.89 (95% CI: 0.82, 0.93), the positive likelihood ratio was 5.9 (95% CI: 3.5, 9.8), the negative likelihood ratio was 0.38 (95% CI: 0.27, 0.53), and the diagnostic odds ratio (DOR) was 16 (95% CI: 8, 32). The diagnostic sensitivity of CA72-4 diagnosis alone was 0.58 (95% CI: 0.40, 0.73), specificity was 0.86 (95% CI: 0.80, 0.90), the positive likelihood ratio was 4.0 (95% CI: 3.1, 5.1), the negative likelihood ratio was 0.49 (95% CI: 0.34, 0.71), and the DOR was 8 (95% CI: 5, 14). The area under the ROC curve (AUC) values of the combined three diagnosis and CA72-4 diagnosis alone were 0.87 (95% CI: 0.83, 0.89) and 0.84 (95% CI: 0.81, 0.87), respectively, the difference was statistically significant (Z=4.86, P<0.05).
UNASSIGNED: The combined use of the 3 tumor markers has higher sensitivity and specificity than single marker diagnosis in the diagnosis of gastric cancer.