BACKGROUND: To date, carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) have been widely used for the screening, diagnosis and prediction of biliary tract cancer (BTC) patients. However, few studies with large sample sizes of carbohydrate antigen 50 (CA50) were reported in BTC patients.
METHODS: A total of 1121 patients from the Liver Cancer Clin-Bio Databank of Anhui Hepatobiliary Surgery Union between January 2017 and December 2022 were included in this study (673 in the training cohort and 448 in the validation cohort): among them, 458 with BTC, 178 with hepatocellular carcinoma (HCC), 23 with combined hepatocellular-cholangiocarcinoma, and 462 with nontumor patients. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the diagnostic efficacy and clinical usefulness.
RESULTS: ROC curves obtained by combining CA50, CA19-9, and AFP showed that the AUC value of the diagnostic MODEL 1 was 0.885 (95% CI 0.856-0.885, specificity 70.3%, and sensitivity 84.0%) in the training cohort and 0.879 (0.841-0.917, 76.7%, and 84.3%) in the validation cohort. In addition, comparing iCCA and HCC (235 in the training cohort, 157 in the validation cohort), the AUC values of the diagnostic MODEL 2 were 0.893 (95% CI 0.853-0.933, specificity 96%, and sensitivity 68.6%) in the training cohort and 0.872 (95% CI 0.818-0.927, 94.2%, and 64.6%) in the validation cohort.
CONCLUSIONS: The model combining CA50, CA19-9, and AFP not only has good diagnostic value for BTC but also has good diagnostic value for distinguishing iCCA and HCC.

BACKGROUND: The aim is to establish and verify reference intervals (RIs) for serum tumor markers for an apparently healthy elderly population in Southwestern China using an indirect method.
METHODS: Data from 35,635 apparently healthy elderly individuals aged 60 years and above were obtained in West China Hospital from April 2020 to December 2021. We utilized the Box-Cox conversion combined with the Tukey method to normalize the data and eliminate outliers. Subgroups are divided according to gender and age to examine the division of RIs. The Z-test was used to compare differences between groups, and 95% distribution RIs were calculated using a nonparametric method.
RESULTS: In the study, we observed that the RIs for serum ferritin and Des-γ-carboxy prothrombin (DCP) were wider for men, ranging from 64.18 to 865.80 ng/ml and 14.00 to 33.00 mAU/ml, respectively, compared to women, whose ranges were 52.58 to 585.88 ng/ml and 13.00 to 29.00 mAU/ml. For other biomarkers, the overall RIs were established as follows: alpha-fetoprotein (AFP) 0-6.75 ng/ml, carcinoembryonic antigen (CEA) 0-4.85 ng/ml, carbohydrate antigen15-3 (CA15-3) for females 0-22.00 U/ml, carbohydrate antigen19-9 (CA19-9) 0-28.10 U/ml, carbohydrate antigen125 (CA125) 0-20.96 U/ml, cytokeratin 19 fragment (CYFRA21-1) 0-4.66 U/ml, neuron-specific enolase (NSE) 0-19.41 ng/ml, total and free prostate-specific antigens (tPSA and fPSA) for males 0-5.26 ng/ml and 0-1.09 ng/ml. The RIs for all these biomarkers have been validated through our rigorous processes.
CONCLUSIONS: This study preliminarily established 95% RIs for an apparently healthy elderly population in Southwestern China. Using real-world data and an indirect method, simple and reliable RIs for an elderly population can be both established and verified, which are suitable for application in various clinical laboratories.

BACKGROUND: Genetic polymorphisms of molecules are known to cause individual differences in the therapeutic efficacy of anticancer drugs. However, to date, germline mutations (but not somatic mutations) for anticancer drugs have not been adequately studied. The objective of this study was to investigate the association between germline polymorphisms of gemcitabine metabolic and transporter genes with carbohydrate antigen 19-9 (CA 19-9) response (decrease ≥50% from the pretreatment level at 8 weeks) and overall survival (OS) in patients with metastatic pancreatic cancer who receive gemcitabine-based chemotherapy.
METHODS: This multicenter, prospective, observational study enrolled patients with metastatic pancreatic cancer patients who were receiving gemcitabine monotherapy or gemcitabine plus nanoparticle albumin-bound paclitaxel combination chemotherapy. Thirteen polymorphisms that may be involved in gemcitabine responsiveness were genotyped, and univariate and multivariate logistic regression analyses were used to determine the association of these genotypes with CA 19-9 response and OS. The significance level was set at 5%.
RESULTS: In total, 180 patients from 11 hospitals in Japan were registered, and 159 patients whose CA 19-9 response could be assessed were included in the final analysis. Patients who had a CA 19-9 response had significantly longer OS (372 vs. 241 days; p = .007). RRM1 2464A>G and RRM2 175T>G polymorphisms suggested a weak association with CA 19-9 response and OS, but it was not statistically significant. COX-2 -765G>C polymorphism did not significantly correlate with CA 19-9 response but was significantly associated with OS (hazard ratio, 2.031; p = .019).
CONCLUSIONS: Genetic polymorphisms from the pharmacokinetics of gemcitabine did not indicate a significant association with efficacy, but COX-2 polymorphisms involved in tumor cell proliferation might affect OS.

BACKGROUND: The prognostic value of carbohydrate antigen 19-9 (CA19-9) is known to be affected by elevated bilirubin levels in patients with gallbladder carcinoma (GBC). The clinical significance of changes in the ratio of CA19-9 levels to total bilirubin (TB) levels in patients with GBC after curative-intent resection remains unknown. The aim of this study was to determine the prognostic value of changes in preoperative and postoperative CA19-9/TB ratio in these patients.
METHODS: Prospectively collected data on consecutive patients who underwent curative-intent resection for GBC between January 2015 and December 2020 stored in a multicenter database from 10 hospitals were analyzed in this retrospective cohort study. Based on the adjusted CA19-9 defined as the ratio of CA19-9 to TB, and using 2×10 3  U/µmol as the upper normal value, patients were divided into a normal group (with normal preoperative and postoperative adjusted CA19-9), a normalization group (with abnormal preoperative but normal postoperative adjusted CA19-9), and a non-normalization group (with abnormal postoperative adjusted CA19-9). The primary outcomes were overall survival (OS) and recurrence-free survival (RFS). The log-rank test was used to compare OS and RFS among the groups. The Cox regression model was used to determine factors independently associated with OS and RFS.
RESULTS: The normal group ( n =179 patients) and the normalization group ( n =73 patients) had better OS and RFS than the non-normalization group ( n =65 patients) (the 3-year OS rates 72.0%, 58.4% and 24.2%, respectively; the RFS rates 54.5%, 25.5% and 11.8%, respectively; both P <0.001). There were no significant differences between the normal and the normalization groups in OS and RFS (OS, P =0.255; RFS, P =0.130). Cox regression analysis confirmed that the non-normalization group was independently associated with worse OS and RFS. Subgroup analysis revealed that the non-normalization group of patients who received adjuvant therapy had significantly improved OS and RFS as compared to those who did not receive adjuvant therapy (OS, P =0.025; RFS, P =0.003).
CONCLUSIONS: Patients with GBC who underwent curative-intent surgical resection with postoperative abnormal levels of adjusted CA19-9 (the CA19-9/TB ratio) were associated with poorer long-term survival outcomes. Adjuvant therapy after surgery improved the long-term outcomes of these patients.

OBJECTIVE: We investigated true indication of neoadjuvant therapy (NAT) in resectable pancreatic cancer and the optimal surgical timing in borderline resectable pancreatic cancer.
METHODS: A total of 687 patients with resectable or borderline resectable pancreatic cancer were enrolled. Survival analysis was performed by intention-to-treat analysis and propensity score matching (PSM) was conducted.
RESULTS: In resectable disease, the NAT group showed better overall survival (OS) compared with the upfront group. Multivariate analysis identified CA19-9 level (≥100 U/mL) and lymph node metastasis to be prognostic factors, and a tumor size of 25 mm was the optimal cut-off value to predict lymph node metastasis. There was no significant survival difference between patients with a tumor size ≤25 mm and CA19-9 < 100 U/mL and those in the NAT group. In borderline resectable disease, OS in the NAT group was significantly better than that in the upfront group. CEA (≥5 ng/mL) and CA19-9 (≥100 U/mL) were identified as prognostic factors; however, the OS of patients fulfilling these factors was worse than that of the NAT group.
CONCLUSIONS: NAT could be unnecessary in patients with tumor size ≤25 mm and CA19-9 < 100 U/mL in resectable disease. In borderline resectable disease, surgery should be delayed until tumor marker levels are well controlled.

The harmonization status of most tumor markers (TMs) is unknown. We report a feasibility study performed to determine whether external quality assessment (EQA) programs can be used to obtain insights into the current harmonization status of the tumor markers α-fetoprotein (AFP), prostate specific antigen (PSA), carcinoembryonic antigen (CEA), cancer antigen (CA)125, CA15-3 and CA19-9.
EQA sample results provided by 6 EQA providers (INSTAND [Germany], Korean Association of External Quality Assessment Service [KEQAS, South Korea], National Center for Clinical Laboratories [NCCL, China], United Kingdom National External Quality Assessment Service [UK NEQAS, United Kingdom], Stichting Kwaliteitsbewaking Medische Laboratoriumdiagnostiek [SKML, the Netherlands], and the Royal College of Pathologists of Australasia Quality Assurance Programs [RCPAQAP, Australia]) between 2020 and 2021 were used. The consensus means, calculated from the measurement procedures present in all EQA programs (Abbott Alinity, Beckman Coulter DxI, Roche Cobas, and Siemens Atellica), was used as reference values. Per measurement procedure, the relative difference between consensus mean for each EQA sample and the mean of all patient-pool-based EQA samples were calculated and compared to minimum, desirable, and optimal allowable bias criteria based on biological variation.
Between 19040 (CA15-3) and 25398 (PSA) individual results and 56 (PSA) to 76 (AFP) unique EQA samples were included in the final analysis. The mean differences with the consensus mean of patient-pool-based EQA samples for all measurement procedures were within the optimum bias criterion for AFP, the desirable bias for PSA, and the minimum bias criterion for CEA. However, CEA results <8 µg/L exceeded the minimum bias criterion. For CA125, CA15-3, and CA19-9, the harmonization status was outside the minimum bias criterion, with systematic differences identified.
This study provides relevant information about the current harmonization status of 6 tumor markers. A pilot harmonization investigation for CEA, CA125, CA15-3, and CA19-9 would be desirable.

We previously showed that the nab-paclitaxel plus S-1 (NPS) regimen had promising effects against metastatic pancreatic ducal adenocarcinoma (mPDAC), whose efficacy however could not be precisely predicted by routine biomarkers. This prospective study aimed to investigate the values of mutations in circulating tumor DNA (ctDNA) and their dynamic changes in predicting response of mPDAC to NPS chemotherapy.
Paired tumor tissue and blood samples were prospectively collected from patients with mPDAC receiving first-line NPS chemotherapy, and underwent next-generation sequencing with genomic profiling of 425 genes for ctDNA. High mutation allelic frequency (MAF) was defined as ≥ 30% and ≥ 5% in tumor tissue and blood, respectively. Kappa statistics were used to assess agreement between mutant genes in tumor and ctDNA. Associations of mutations in ctDNA and their dynamic changes with tumor response, overall survival (OS), and progression-free survival (PFS) were assessed using the Kaplan-Meier method, multivariable-adjusted Cox proportional hazards regression, and longitudinal data analysis.
147 blood samples and 43 paired tumor specimens from 43 patients with mPDAC were sequenced. The most common driver genes with high MAF were KRAS (tumor, 35%; ctDNA, 37%) and TP53 (tumor, 37%; ctDNA, 33%). Mutation rates of KRAS and TP53 in ctDNA were significantly higher in patients with liver metastasis, with baseline CA19-9 ≥ 2000 U/mL, and/or without an early CA19-9 response. κ values for the 5 most commonly mutated genes between tumor and ctDNA ranged from 0.48 to 0.76. MAFs of the genes mostly decreased sequentially during subsequent measurements, which significantly correlated with objective response, with an increase indicating cancer progression. High mutations of KRAS and ARID1A in both tumor and ctDNA, and of TP53, CDKN2A, and SMAD4 in ctDNA but not in tumor were significantly associated with shorter survival. When predicting 6-month OS, AUCs for the 5 most commonly mutated genes in ctDNA ranged from 0.59 to 0.84, larger than for genes in tumor (0.56 to 0.71) and for clinicopathologic characteristics (0.51 to 0.68). Repeated measurements of mutations in ctDNA significantly differentiated survival and tumor response. Among the 31 patients with ≥ 2 ctDNA tests, longitudinal analysis of changes in gene MAF showed that ctDNA progression was 60 and 58 days ahead of radiologic and CA19-9 progression for 48% and 42% of the patients, respectively.
High mutations of multiple driving genes in ctDNA and their dynamic changes could effectively predict response of mPDAC to NPS chemotherapy, with promising reliable predictive performance superior to routine clinicopathologic parameters. Inspiringly, longitudinal ctDNA tracking could predict disease progression about 2 months ahead of radiologic or CA19-9 evaluations, with the potential to precisely devise individualized therapeutic strategies for mPDAC.

BACKGROUND: The applicability of neoadjuvant treatment (NAT) for resectable pancreatic ductal adenocarcinoma (PDAC) has arisen, however, high-level evidence is lacking. This study aimed to explore patient subgroups with high-risk resectable PDAC for selecting candidates who may benefit from NAT.
METHODS: The 1132 patients with resectable or borderline resectable PDAC who underwent surgery between 2007 and 2021 were retrospectively reviewed. Patients with resectable PDAC without contact of major vessels (R-no contact) ( n =651), with contact of portal vein or superior mesenteric vein (PV/SMV) ≤180° (R-contact) ( n =306), and borderline resectable PDAC without arterial involvement (BR-V) ( n =175) were analyzed.
RESULTS: The mean age was 64.3±9.8 years, and 647 patients (57.2%) were male. The median follow-up was 26 months in the entire cohort. Patients with resectable PDAC without vascular contact had the most improved overall survival (OS) (median; 31.5 months). OS did not significantly differ between NAT and upfront surgery in the entire resectable PDAC cohort. However, in R-contact group, NAT showed significantly improved OS compared to upfront surgery (33 vs. 23 months). Neoadjuvant FOLFIRINOX was showed a better OS than gemcitabine-based regimens in patients who underwent NAT (34 vs. 24 months). NAT was associated with a better survival in the patients with CA 19-9 level ≥150 U/ml, only when the tumor has PV/SMV contact in resectable disease (40 vs. 19 months, P =0.001).
CONCLUSIONS: NAT can be considered as an effective treatment in patients with resectable PDAC, particularly when the tumor is in contact with PV/SMV and CA 19-9 ≥150 U/ml.

Postoperative CA19-9 elevation after pancreatic cancer resection suggests recurrence but can also occur in benign conditions. This study aimed to investigate the interpretation of postoperative CA19-9 elevation after pancreatic cancer surgery in terms of cancer recurrence. A cohort of patients undergoing pancreatectomy for pancreatic cancer at our hospital was included. Among them, 52 patients exhibited postoperative CA19-9 elevation without radiological evidence of recurrence. These patients were evaluated with follow-up CA19-9 measurements. The CA19-9 increase rates were calculated based on the first elevation and the follow-up measurement. The association between the CA19-9 increase rate and tumor recurrence was assessed. Patients with a CA19-9 increase rate of ≥ 30% had a significantly higher frequency of recurrence within 3 months compared to those without such an increase (p = 0.0002). Multivariate analysis demonstrated that a CA19-9 increase rate of ≥ 30% was an independent risk factor for recurrence (odds ratio 8.17, p = 0.0309). The CA19-9 value at the first elevation (p = 0.1794) and at the follow-up measurement (p = 0.1121) were not associated with recurrence. After the first postoperative CA19-9 elevation, the CA19-9 increase rate based on follow-up measurements can serve as a predictive factor for tumor recurrence.

OBJECTIVE: This study examined the clinical significance of very high preoperative carbohydrate antigen 19-9 (CA19-9) levels in patients with early-stage colorectal cancer (CRC).
METHODS: We retrospectively analyzed the clinicopathological data of patients who underwent curative resection for primary CRC (c-Stage I-III) between 2004 and 2022 in our facility. The patients were classified into three groups according to the preoperative CA19-9 level: normal (≤37.0 U/ml), high (>37.0 to ≤100.0 U/ml), and very high (>100.0 U/ml).
RESULTS: Of 971 patients, 885 (91.1%), 67 (6.9%), and 19 (2.0%) had normal, high, and very high CA19-9 levels, respectively. Overall survival (very high vs. normal: p<0.0001, very high vs. high: p=0.01) and recurrence-free survival (very high vs. normal: p<0.0001, very high vs. high: p=0.18) were significantly worse in the very high group. On multivariate analysis including TNM stage, very high preoperative CA19-9 levels were independently associated with worse overall (odds ratio=4.54; 95% confidence interval=2.03-10.16; p=0.0002) and recurrence-free survival (odds ratio=3.49; 95% confidence interval=1.82-6.69; p=0.0002).
CONCLUSIONS: High preoperative CA19-9 levels were associated with poor survival in early-stage CRC. Careful intraoperative observation and close follow-up might be necessary.