The carcinoembryonic antigen ratio is a potential predictor of survival in recurrent colorectal cancer

Tumor Marker Trajectories and Survival Analysis in Patients With Normal Carcinoembryonic Antigen Ranges After Colorectal Cancer Resection

BACKGROUND

Evidence regarding postoperative CEA for predicting long-term outcomes of colorectal cancer remains controversial, especially in patients with normal postoperative CEA.

OBJECTIVE

To investigate the risk difference among different postoperative CEA trajectories in patients with normal postoperative CEA after curative colorectal cancer resection.

DESIGN

This cohort study was conducted at a comprehensive cancer center and included data retrieved from a prospectively collected database between January 2006 and December 2018.

SETTINGS

Retrospective cohort study.

PATIENTS

Patients with colorectal cancer who underwent surgery for primary stage I to III colorectal adenocarcinoma were included and those with postoperative CEA >5 ng/mL were excluded.

INTERVENTIONS

Standard curative radical resection was performed.

MAIN OUTCOME MEASURES

Ten-year overall survival and disease-free survival were analyzed.

RESULTS

The study population (n = 8156) was categorized into 6 trajectories: persistent-ultralow (n = 2351), persistent-low (n = 2474), gradually decrease (n = 401), persistent-medium (n = 1727), slightly increase (n = 909), and around-upper-limit (n = 394). The median follow-up time was 7.8 years, and the median time frame in which CEA was measured to determine trajectory was 2.6 years. The persistent-ultralow group had the highest 10-year overall survival (85.1%) and disease-free survival (82.7%). The around-upper-limit group had the lowest 10-year overall survival (55.5%) and disease-free survival (53.4%). The adjusted HR trend was comparable to the crude HR of the persistent-ultralow group. Consequently, the higher initial serum CEA groups had higher HRs of overall survival and disease-free survival. The adjusted HR of overall survival was 2.96 (95% CI, 2.39-3.66) and of disease-free survival was 2.66 (95% CI, 2.18-3.69) for the around-upper-limit groups.

LIMITATIONS

Retrospective design.

CONCLUSIONS

The postoperative serum CEA trajectory is an independent factor associated with long-term outcomes. Although CEA levels were all within normal range, higher levels of postoperative serum CEA trajectory correlated with worse long-term oncological outcomes. See Video Abstract.

TRAYECTORIAS DE MARCADORES TUMORALES Y ANLISIS DE SUPERVIVENCIA EN PACIENTES CON RANGOS NORMALES DE ANTGENO CARCINOEMBRIONARIO POSTERIOR A RESECCIN DE CNCER COLORRECTAL

ANTECEDENTES:La evidencia sobre el CEA post operatorio para la predicción de los resultados a largo plazo del cáncer colorrectal sigue siendo controversial, especialmente en pacientes con CEA post quirúrgico normal.OBJETIVO:Investigar la diferencia de riesgo entre diferentes trayectorias postoperatorias del CEA en pacientes con CEA post quirúrgico normal tras la resección curativa del cáncer colorrectal.DISEÑO:Este estudio de cohorte se realizó en un centro oncológico integral e incluyó datos recuperados de una base de datos recopilada prospectivamente entre enero de 2006 y diciembre de 2018.AJUSTES:Estudio de cohorte retrospectivo.PACIENTES:Se incluyeron pacientes con el diagnostico de CCR que fueron sometidos a cirugía por adenocarcinoma colorrectal primario en estadio I-III. Se excluyeron pacientes con CEA postoperatorio >5 ng/mL.INTERVENCIONES:Se realizó una resección radical curativa estandarizada.PRINCIPALES MEDIDAS DE RESULTADO:Se analizaron la supervivencia general a diez años y la supervivencia libre de enfermedad.RESULTADOS:La población de estudio (n = 8156) fue clasificada en seis trayectorias, que incluyeron ultrabajo persistente (n = 2351), bajo persistente (n = 2474), disminución gradual (n = 401), medio persistente (n = 1727), aumento leve (n = 909) y alrededor del límite superior (n = 394). La mediana del tiempo de seguimiento fue de 7,8 años y la mediana del período de tiempo en el que el CEA fue medido para determinar la trayectoria fue de 2,6 años. El grupo ultrabajo persistente tuvo la mayor supervivencia general a 10 años (85,1 %) y supervivencia libre de enfermedad (82,7 %). El grupo alrededor del límite superior tuvo la supervivencia general a 10 años más baja (55,5 %) y la supervivencia libre de enfermedad (53,4 %). La tendencia del índice de riesgo ajustado fue comparable al índice de riesgo bruto del grupo ultrabajo persistente. En consecuencia, los grupos con CEA sérico iniciales más altos tenían índices de riesgos más altos de supervivencia general y supervivencia libre de enfermedad. Los índices de riesgos ajustados de supervivencia general/supervivencia libre de enfermedad fueron 2,96/2,66 (intervalo de confianza del 95 %: 2,39-3,66/2,18-3,69) para los grupos cercanos al límite superior.LIMITACIONES:El estudio estuvo limitado por su diseño retrospectivo.CONCLUSIONES:La trayectoria del CEA sérico postoperatorio es un factor independiente asociado con resultados a largo plazo. Aunque los niveles de CEA se encontraban todos dentro del rango normal, los niveles más altos de trayectoria del CEA en suero posoperatorio se correlacionaron con peores resultados oncológicos a largo plazo. (Traducción-Dr Osvaldo Gauto ).

Accurate method for value assignment of carcinoembryonic antigen reference materials

BACKGROUND

In this study, we explored the commutability of reference materials (RMs) for carcinoembryonic antigen (CEA), selected the appropriate diluent matrix of the first International Reference Preparation (IRP) 73/601 of the World Health Organization (WHO 73/601) for CEA, and improved the comparability of CEA measurement results among different assay systems.

METHODS

Forty serum samples were divided into five aliquots. WHO 73/601 was diluted into nine concentrations using five diluents with different components, and the candidate RMs for CEA at five concentrations (C1-C5) were prepared by the Beijing Clinical Laboratory Center (BCCL). The samples were analyzed via five automated CEA immunoassays.

RESULTS

Carcinoembryonic antigen candidate RMs were commutable among all immunoassays based on the CLSI approach and among 7 of 10 assay combinations based on the IFCC approach. WHO 73/601 diluted in phosphate-buffered saline (PBS) was commutable among all assays based on the CLSI approach and among 5 of 10 pairwise comparisons based on the IFCC approach with correction of bias at diluted concentrations, except for the lowest concentration, which had the smallest variation among systems. The median percentage biases among assays were decreased after calibration.

CONCLUSION

The BCCL candidate RMs (C2-C5) for CEA were commutable among all immunoassays. WHO 73/601 RMs diluted in a PBS buffer matrix were selected as common calibrators for five immunoassays, which reduced bias, thereby effectively improving the harmonization of CEA detection; therefore, they could be used to assign values to CEA candidate RMs developed by BCCL. Our findings promote the harmonization of CEA detection in immunoassays.

Predicting disease-free survival in colorectal cancer by circulating tumor DNA methylation markers

BACKGROUND

Recurrence represents a well-known poor prognostic factor for colorectal cancer (CRC) patients. This study aimed to establish an effective prognostic prediction model based on noninvasive circulating tumor DNA methylation markers for CRC patients receiving radical surgery.

RESULTS

Two methylation markers (cg11186405 and cg17296166) were identified by Cox regression and receiver operating characteristics, which could classify CRC patients into high recurrence risk and low recurrence risk group. The 3-year disease-free survival was significantly different between CRC patients with low and high recurrence risk [Training set: hazard ratio (HR) 28.776, 95% confidence interval (CI) 3.594-230.400; P = 0.002; Validation set: HR 7.796, 95% CI 1.425-42.660, P = 0.018]. The nomogram based on the above two methylation markers and TNM stage was established which demonstrated robust prognostic prediction potential, as evidenced by the decision curve analysis result.

CONCLUSIONS

A cell-free DNA methylation model consisting of two DNA methylation markers is a promising method for prognostic prediction in CRC patients.