Carcinoembryonic antigen has prognostic value for tumor downstaging and recurrence in rectal cancer after preoperative chemoradiotherapy and curative surgery: A multi-institutional and case-matched control study of KROG 14-12

Effectiveness of PD-1 inhibitor-based first-line therapy in Chinese patients with metastatic gastric cancer: a retrospective real-world study

Objective

Programmed cell death protein-1 (PD-1) inhibitor-based therapy has demonstrated promising results in metastatic gastric cancer (MGC). However, the previous researches are mostly clinical trials and have reached various conclusions. Our objective is to investigate the efficacy of PD-1 inhibitor-based treatment as first-line therapy for MGC, utilizing real-world data from China, and further analyze predictive biomarkers for efficacy.

Methods

This retrospective study comprised 105 patients diagnosed with MGC who underwent various PD-1 inhibitor-based treatments as first-line therapy at West China Hospital of Sichuan University from January 2018 to December 2022. Patient characteristics, treatment regimens, and tumor responses were extracted. We also conducted univariate and multivariate analyses to assess the relationship between clinical features and treatment outcomes. Additionally, we evaluated the predictive efficacy of several commonly used biomarkers for PD-1 inhibitor treatments.

Results

Overall, after 28.0 months of follow-up among the 105 patients included in our study, the objective response rate (ORR) was 30.5%, and the disease control rate (DCR) was 89.5% post-treatment, with two individuals (1.9%) achieving complete response (CR). The median progression-free survival (mPFS) was 9.0 months, and the median overall survival (mOS) was 22.0 months. According to both univariate and multivariate analyses, favorable OS was associated with patients having Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-1. Additionally, normal baseline levels of carcinoembryonic antigen (CEA), as well as the combination of PD-1 inhibitors with chemotherapy and trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive MGC, independently predicted longer PFS and OS. However, microsatellite instability/mismatch repair (MSI/MMR) status and Epstein-Barr virus (EBV) infection status were not significantly correlated with PFS or OS extension.

Conclusion

As the first-line treatment, PD-1 inhibitors, either as monotherapy or in combination therapy, are promising to prolong survival for patients with metastatic gastric cancer. Additionally, baseline level of CEA is a potential predictive biomarker for identifying patients mostly responsive to PD-1 inhibitors.

Identifying patients suitable for targeted adjuvant therapy: advances in the field of developing biomarkers for tumor recurrence following irradiation

Introduction

Radiation therapy (RT) is commonly used to treat cancer in conjunction with chemotherapy, immunotherapy, and targeted therapies. Despite the effectiveness of RT, tumor recurrence due to treatment resistance still lead to treatment failure. RT-specific biomarkers are currently lacking and remain challenging to investigate with existing data since, for many common malignancies, standard of care (SOC) paradigms involve the administration of RT in conjunction with other agents.

Areas Covered

Established clinically relevant biomarkers are used in surveillance, as prognostic indicators, and sometimes for treatment planning; however, the inability to intercept early recurrence or predict upfront resistance to treatment remains a significant challenge that limits the selection of patients for adjuvant therapy. We discuss attempts at intercepting early failure. We examine biomarkers that have made it into the clinic where they are used for treatment monitoring and management alteration, and novel biomarkers that lead the field with targeted adjuvant therapy seeking to harness these.

Expert Opinion

Given the growth of data correlating interventions with omic analysis toward identifying biomarkers of radiation resistance, more robust markers of recurrence that link to biology will increasingly be leveraged toward targeted adjuvant therapy to make a successful transition to the clinic in the coming years.

The Correlation Between Survival Benefit of Preoperative Radiotherapy and Pretreatment Carcinoembryonic Antigen Level in Locally Advanced Rectal Cancer

Background

Preoperative radiotherapy followed by radical surgery is the standard treatment for locally advanced rectal cancer; however, its long-term survival benefit remains controversial. This study aimed to determine the relationship between pretreatment carcinoembryonic antigen (CEA) levels and the long-term prognosis of preoperative radiotherapy in locally advanced rectal cancer (LARC) patients.

Methods

Data of LARC patients who underwent surgery between 2011 and 2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) database, and patients were accordingly divided into surgery (S) group and radiotherapy followed by surgery (RT+S) group. The primary outcomes were cancer-specific survival (CSS) and cancer-specific mortality (CSM). CSS was evaluated using Kaplan-Meier analysis, while CSM was evaluated using a competitive risk model. Subgroup analysis was also conducted, which was stratified by pretreatment CEA levels.

Results

A total of 2,760 patients were eligible for this study, including 350 (12.7%) patients in the S group and 2,410 (87.3%) in the RT+S group. There were no significant differences in the CSS and CSM rates at 1, 3, and 4 years between the S and RT+S groups before and after PSM (all p > 0.05). Pretreatment CEA levels were independently associated with CSS and CSM after adjusting for age, sex, stage, pathological factors, and treatment factors (all p < 0.05). Subgroup analysis showed that preoperative radiotherapy would benefit patients with elevated CEA in terms of CSS and CSM (both p < 0.05) but not those patients with normal CEA (both p > 0.05). Further analysis showed that preoperative radiotherapy was an independent protective factor for CSS and CSM in patients with elevated CEA levels (both p < 0.05).

Conclusions

Pretreatment CEA level may be considered a potential biomarker to screen LACR patients who would benefit from preoperative radiotherapy in terms of long-term prognosis.

Follow-up of colorectal cancer and patterns of recurrence

Colorectal cancer is one of the commonest cancers detected as also amongst the most common causes of cancer death. Survival has improved due to better disease understanding and treatment; however, a substantial proportion of patients recur after curative intent therapy. In this article, we will discuss the imaging features of recurrent colorectal cancer and the role of the radiologist in its management.

Serum carcinoembryonic antigen pre-operative level in colorectal cancer: revisiting risk stratification

BACKGROUND

Biomarkers may play a role as predictive and prognostic factors in colorectal cancer patients. The aims of the study were to verify the prognostic role of pre-operative serum carcinoembryonic antigen (CEA) level in predicting overall survival and risk of recurrence in a cohort of colorectal cancer patients and to evaluate optimal cut-off values.

METHODS

A retrospective cohort analysis was performed on colorectal cancer patients undergoing elective curative surgery between 2004 and 2019 at an Italian Academic Hospital. Main outcomes were overall survival, disease-free survival at 3-years and risk of local, loco-regional and distant recurrence during follow-up. A receiver operating characteristic (ROC) curve analysis was plotted using CEA pre-operative values and follow-up data in order to estimate the optimal cut-off values.

RESULTS

A total of 559 patients were considered. The mean CEA value was 12.1 ± 54.1 ng/mL, and the median 29.3 (0-4995) ng/mL. The ROC curve analysis identified 12.5 ng/mL as the best CEA cut-off value to predict the risk of metastatic development after surgery in stage I-III colorectal cancer patients, and 10 ng/mL as the best CEA cut-off value to predict overall survival and disease-free survival in stage III-IV patients. These data suggest a stratification of colorectal cancer patients in three classes of risk: a low risk class (CEA <10 ng/mL), a moderate risk class (CEA 10-12.5 ng/mL) and a high risk class (CEA >12.5 ng/mL).

CONCLUSION

In conclusion, pre-operative serum CEA measurements could integrate information to enhance patient risk stratification and tailored therapy.

Clinical predictors of pathological good response in locally advanced rectal cancer

Purpose

The aim of this study was to identify the clinical predictors of pathological good response (PGR) after neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC) to clarify the indications for local excision.

Methods and materials

A total of 173 patients with LARC (cT3–4/N +) who were treated with nCRT followed by surgery were enrolled in our retrospective study. Patients were categorized into two groups according to the different tumor responses of surgical pathology. Stage ypT0–1N0 was defined as the group with PGR, and stage ypT2–4N0/ypTanyN + was the defined as the pathological poor response (PPR) group, and the potential predictors were compared.

Results

Of 173 patients, PGR was achieved in 57 patients (32.95%). The distance from the inferior margin of the tumor to the anal verge, cT classification, pretreatment carcinoembryonic antigen (CEA) and the interval from the end of radiation to surgery were correlated with pathological response. In the multivariate analysis, the distance from anal verge < 5 cm (OR = 0.443, p = 0.019), pretreatment CEA < 5 ng/mL (OR = 0.412, p = 0.015) and the interval from the end of radiation to surgery ≥ 84 days (OR = 2.652, p = 0.005) were independent predictors of PGR.

Conclusions

The distance from the inferior margin of the tumor to the anal verge, pretreatment CEA and the interval from the end of radiation to surgery were significant predictors of PGR in LARC. A prospective study is needed to further validate these results in the future.

Prognostic Value of Pretreatment Serum CA199 in Patients with Locally Advanced Rectal Cancer Treated with CRT Followed by TME with Normal Pretreatment Carcinoembryonic Antigen Levels

BACKGROUND

Elevated pretreatment carcinoembryonic antigen (CEA) levels are related to poor prognosis in patients with locally advanced rectal cancer (LARC) treated with neo-CRT followed by TME. In patients with normal pretreatment CEA levels, the prognostic significance of carbohydrate antigen 199 (CA199) is controversial.

OBJECTIVES

The aim of this study was to explore the prognostic value of pretreatment serum CA199 in patients with LARC who had normal pretreatment CEA levels treated with neo-CRT followed by curative surgery.

METHODS

A retrospective study of 456 patients with LARC treated with neo-CRT followed by TME between January 2006 and May 2017 was performed. We employed the maximal χ2 method to determine the CA199 threshold of 9.1 U/mL based on the difference in survival and divided patients into 2 groups. Group 1: patients with pretreatment s-CEA < 5 ng/mL and CA199 ≥ 9.1 U/mL. Group 2: patients with pretreatment s-CEA < 5 ng/mL and CA199 < 9.1 U/mL. Overall survival (OS) across CA199 was assessed using Cox proportional hazard regression models (PS:CEA ≥ 5 ng/mL was seen as elevated).

RESULTS

Multivariate analyses demonstrated that the following factors were significantly related to OS in patients with LARC with normal pretreatment CEA levels: ypT (odds ratio [OR] 1.863, p = 0.030), ypN (OR 1.622, p = 0.026), and pretreatment CA199 levels (OR 1.886, p = 0.048).

CONCLUSION

Pretreatment CA199 is an independent factor for OS in patients with LARC with normal pretreatment CEA levels, which may reach the clinic to guide individualized decision-making.

Carcinoembryonic Antigen Improves the Performance of Magnetic Resonance Imaging in the Prediction of Pathologic Response after Neoadjuvant Chemoradiation for Patients with Rectal Cancer

PURPOSE

The purpose of this study was to investigate the role of carcinoembryonic antigen (CEA) levels in improving the performance of magnetic resonance imaging (MRI) for the prediction of pathologic response after the neoadjuvant chemoradiation (NCRT) for patients with rectal cancer.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 524 rectal cancer patients who underwent NCRT and total mesorectal excision between January 2009 and December 2014. The performances of MRI with or without CEA parameters (initial CEA and CEA dynamics) for prediction of pathologic tumor response grade (pTRG) were compared by receiver-operating characteristic analysis with DeLong's method. Cox regression was used to identify the independent factors associated to pTRG and disease-free survival (DFS) after NCRT.

RESULTS

The median follow-up was 64.0 months (range, 3.0 to 113.0 months). On multivariate analysis, poor tumor regression grade on MRI (mrTRG; p < 0.001), initial CEA (p < 0.001) and the mesorectal fascia involvement on MRI before NCRT (mrMFI; p=0.054) showed association with poor pTRG. The mrTRG plus CEA parameters showed significantly improved performances in the prediction of pTRG than mrTRG alone. All of mrTRG, mrMFI, and initial CEA were also identified as independent factors associated with DFS. The initial CEA further discriminated DFS in the subgroups with good mrTRG or that without mrMFI.

CONCLUSION

The CEA parameters significantly improved the performance of MRI in the prediction of pTRG after NCRT for patients with rectal cancer. The DFS was further discriminated by initial CEA level in the groups with favorable MRI parameters.

Pathologic Staging Inconsistency Between ypT4N0 (stage II) and ypT1-2N1 (stage III) After Preoperative Chemoradiotherapy and Total Mesorectal Excision in Rectal Cancer: A Multi-Institutional Study

BACKGROUND

In the Surveillance, Epidemiology, and End Results population-based data, the survival curves reversed between T4N0 (stages IIB or IIC) and T1-2N1 (stage IIIA) in rectal cancer. However, T4N0 had a higher stage than T1-2N1 in the current colorectal staging system.

PATIENTS AND METHODS

We analyzed 1804 patients with rectal cancer who were treated with preoperative chemoradiotherapy and curative surgery. We grouped patients by pathologic stage, and recurrence-free survival (RFS) and overall survival rates were calculated and compared for each stage. We evaluated prognostic factors that influenced recurrence and survival.

RESULTS

In the recurrence and survival analysis, 3-year RFS rates were 95.9% for ypStage 0, 94.0% for ypStage I, 78.9% for ypStage IIA, 55.8% for ypStage IIB/C, 80.2% for ypStage IIIA, 64.6% for ypStage IIIB, and 44.9% for ypStage IIIC. Patients with ypStage IIB/C showed significantly worse RFS (P = .004) than did those with ypStage IIIA. The ypStage IIB/C group showed significantly higher rates of both locoregional recurrence (24.3% vs. 5.5%; P = .02) and distant metastasis (31.6% vs. 17.1%; P = .048) than did the ypStage IIIA group. Compared with ypStage IIIA, ypStage IIB/C showed significantly higher pre-chemoradiotherapy carcinoembryonic antigen (P = .004), circumferential radial margin involvement (P = .001), and positive perineural invasion (P = .014).

CONCLUSION

Patients with rectal cancer staged ypT4N0 were associated with higher locoregional recurrence and distant metastasis rates than those staged ypT1-2N1 in the current staging system.

UGT1A1 polymorphisms in rectal cancer associated with the efficacy and toxicity of preoperative chemoradiotherapy using irinotecan

The purpose of the present study was to assess the efficacy and toxicity of preoperative chemoradiotherapy using irinotecan against locally advanced lower rectal cancer according to UDP-glucuronosyltransferase 1A1 (UGT1A1) polymorphisms. Between 2009 and 2016, 46 patients with resectable rectal cancer (T3-T4, N0-N2, M0) received preoperative chemoradiotherapy consisting of 80 mg/m2 per day tegafur/gimeracil/oteracil (S-1; days 1-5, 8-12, 22-26, and 29-33), 60 mg/m2 per day irinotecan (days 1, 8, 22, and 29), and 45 Gy radiation (1.8 Gy/day, 5 days per week for 5 weeks). Six to eight weeks after completing chemoradiotherapy, total mesorectal excision was carried out. Patients with UGT1A1 polymorphisms were divided into WT (n = 26), heterozygous (n = 15), and homozygous (n = 5) groups, the latter including double heterozygosities. We evaluated associations between clinical characteristics, including UGT1A1 polymorphisms, and chemoradiotherapy efficacy and toxicity. Incidence rates of grade 3+ neutropenia and diarrhea were 17.0% and 30.4%, respectively. Relative dose intensity was 89.3%. Pathological complete response rate (grade 3) was 26.1%, and the good response (grade 2/3) rate was 84.8%. UGT1A1 polymorphisms were significantly associated with neutropenia and pathological good responses, but not with diarrhea. UGT1A1 polymorphism was the only predictive factor for pathological good responses. Our results indicate that UGT1A1 polymorphism is a predictive factor to determine the clinical efficacy of preoperative chemoradiotherapy and hematological toxicity induced by chemoradiotherapy using irinotecan in locally advanced rectal cancer patients.

Prognostic Role of Carcinoembryonic Antigen Level after Preoperative Chemoradiotherapy in Patients with Rectal Cancer

BACKGROUND

The prognostic role of post-chemoradiotherapy (CRT) carcinoembryonic antigen (CEA) level is not clear. We evaluated the prognostic significance of post-CRT CEA level in patients with rectal cancer after preoperative CRT.

METHODS

We reviewed 659 consecutive patients who underwent preoperative CRT and total mesorectal excision for non-metastatic rectal cancer. Patients were categorized into two groups according to post-CRT serum CEA level: low CEA (< 5 ng/mL) and high CEA (≥ 5 ng/mL).

RESULTS

Median post-CRT CEA level was 1.7 ng/mL (range, 0.1-207.0). A high post-CRT level was significantly associated with ypStage, ypT category, tumor regression grade, and pre-CRT CEA level. The 5-year overall survival rate of the 659 patients was 87.8% with a median follow-up period of 57.0 months (range, 1.4-176.4). When the post-CRT CEA groups were divided into groups according to pre-CRT CEA level, the 5-year overall survival rates were significantly different (P < 0.001 and P = 0.001, respectively). Post-CRT CEA level was an independent prognostic factor for overall survival. Multivariate analysis revealed that operation method, differentiation, perineural invasion, postoperative chemotherapy, tumor regression grade, and post-CRT CEA level were independent prognostic factors for overall survival.

CONCLUSION

The level of serum CEA after preoperative CRT was an independent prognostic factor for overall survival in patients with rectal cancer.

Relations of Changes in Serum Carcinoembryonic Antigen Levels before and after Neoadjuvant Chemoradiotherapy and after Surgery to Histologic Response and Outcomes in Patients with Locally Advanced Rectal Cancer

OBJECTIVES

The histologic response to neoadjuvant chemoradiotherapy (nCRT) has been intimately related to outcomes in locally advanced rectal cancer. Serum carcinoembryonic antigen (CEA) levels change after nCRT and after surgery as compared with before nCRT.

METHODS

The subjects were 149 patients with locally advanced rectal cancer who received nCRT between 2005 and 2013. The patients were divided into 4 groups according to the serum CEA levels: group 1, 55 patients with negative serum CEA levels before nCRT; group 2, 41 patients with positive serum CEA levels before nCRT that became negative after nCRT; group 3, 37 patients with positive serum CEA levels after nCRT that became negative after surgery; and group 4, 16 patients with positive serum CEA levels after nCRT as well as after surgery.

RESULTS

Pathological complete response, T downstaging, and tumor shrinkage were significantly higher in group 1 than in other groups. Disease-free survival was significantly poorer in group 4. The lack of a decrease in the serum CEA level in group 4 was most likely attributed to the persistence of micrometastases outside the resection field.

CONCLUSIONS

Changes in serum CEA levels measured before nCRT, after nCRT, and after surgery can be used to reliably predict the histologic response to nCRT and outcomes.

Pretreatment magnetic resonance imaging of regional lymph nodes with carcinoembryonic antigen in prediction of synchronous distant metastasis in patients with rectal cancer

Distant metastasis in patients with rectal cancer remains a problem influencing prognosis. Prediction of synchronous distant metastasis is important for the choice of personalized treatment strategies and postoperative follow-up protocol. So far, there are few studies about the predictive value of MRI features combined with clinical characteristics for synchronous distant metastasis in rectal cancer, especially for the lesions developed within 6 months after surgery. We retrospectively reviewed the pretreatment clinical characteristics and magnetic resonance imaging (MRI) features of 271 patients from January 2010 to December 2011with pathologically confirmed rectal adenocarcinoma and tried to identify independent risk factors for synchronous distant metastasis. Forty-nine patients (18.1%) were confirmed to have synchronous distant metastasis. Multivariate logistic regression model demonstrated that the elevated carcinoembryonic antigen (CEA), positive MRI-predicted lymph nodes staging (mrN), and MRI-predicted mesorectal fascia (mrMRF) involvement were independent risk factors. The odd ratios were 12.2 for elevated CEA, 5.4 for mrN1 and 7.6 for mrN2, and 3.8 for mrMRF involvement, respectively. The accuracy and specificity for predicting synchronous distant metastasis by evaluating the positive mrN combined with elevated CEA were improved to 87.8% and 94.6%, respectively. The accuracy, sensitivity and specificity of positive mrN assessment were 86.1%, 71.4% and 91.7%, respectively using the histopathologic results as the reference standard. Altogether, our findings suggest that pretreatment positive mrN and elevated CEA are independent risk factors for synchronous distant metastasis in rectal cancer and combination of both could help to recognize the patients with high risk for structuring personalized treatment protocol.

The Impact of Surgical Timing on Pathologic Tumor Response after Short Course and Long Course Preoperative Chemoradiation for Locally Advanced Rectal Adenocarcinoma

Purpose

A pooled analysis of multi-institutional trials was performed to analyze the effect of surgical timing on tumor response by comparing short course concurrent chemoradiotherapy (CCRT) with long course CCRT followed by delayed surgery in locally advanced rectal cancer.

Materials and Methods

Three hundred patients with cT3-4N0-2 rectal adenocarcinoma were included. Long course patients from KROG 14-12 (n=150) were matched 1:1 to 150 short course patients from KROG 10-01 (NCT01129700) and KROG 11-02 (NCT01431599) according to stage, age, and other risk factors. The primary endpoint was to determine the interval between surgery and the last day of neoadjuvant CCRT which yields the best tumor response after the short course and long course CCRT. Downstaging was defined as ypT0-2N0M0 and pathologic complete response (ypCR) was defined as ypT0N0M0, respectively.

Results

Both the long and short course groups achieved lowest downstaging rates at < 6 weeks (long 20% vs. short 8%) and highest downstaging rates at 6-7 weeks (long 44% vs. short 40%). The ypCR rates were lowest at < 6 weeks (both long and short 0%) and highest at 6-7 weeks (long 21% vs. short 11%) in both the short and long course arms. The downstaging and ypCR rates of long course group gradually declined after the peak at 6-7 weeks and those of the short course group trend to constantly increase afterwards.

Conclusion

It is optimal to perform surgery at least 6 weeks after both the short course and long course CCRT to obtain maximal tumor regression in locally advanced rectal adenocarcinoma.

Elevated CEA is associated with worse survival in recurrent rectal cancer

This study investigated the prognostic impact of serum carcinoembryonic antigen (CEA) level in recurrent rectal cancer. We reviewed 745 patients who developed recurrence after curative treatment for rectal cancer between January 2000 and December 2012. Multivariate analyses for survival revealed that age > 60 years (p = 0.005), r-CEA ≥ 5 ng/ml (p < 0.001), disease free interval (DFI) < 12 months (p < 0.001), and palliative or conservative treatment (p < 0.001) were unfavorable factors.

Preoperative chemoradiotherapy versus postoperative chemoradiotherapy for stage II-III resectable rectal cancer: a meta-analysis of randomized controlled trials

Purpose

Whether preoperative chemoradiotherapy (CRT) is better than postoperative CRT in oncologic outcome and toxicity is contentious in prospective randomized clinical trials. We systematically analyze and compare the treatment result, toxicity, and sphincter preservation rate between preoperative CRT and postoperative CRT in stage II–III rectal cancer.

Materials and Methods

We searched Medline, Embase, and Cochrane Library from 1990 to 2014 for relevant trials. Only phase III randomized studies performing CRT and curative surgery were selected and the data were extracted. Meta-analysis was used to pool oncologic outcome and toxicity data across studies.

Results

Three randomized phase III trials were finally identified. The meta-analysis results showed significantly lower 5-year locoregional recurrence rate in the preoperative-CRT group than in the postoperative-CRT group (hazard ratio, 0.59; 95% confidence interval, 0.41–0.84; p = 0.004). The 5-year distant recurrence rate (p = 0.55), relapse-free survival (p = 0.14), and overall survival (p = 0.22) showed no significant difference between two groups. Acute toxicity was significantly lower in the preoperativeCRT group than in the postoperative-CRT group (p < 0.001). However, there was no significant difference between two groups in perioperative and chronic complications (p = 0.53). The sphincter-saving rate was not significantly different between two groups (p = 0.24). The conversion rate from abdominoperineal resection to low anterior resection in low rectal cancer was significantly higher in the preoperative-CRT group than in the postoperative-CRT group (p < 0.001).

conclusions

As compared to postoperative CRT, preoperative CRT improves only locoregional control, not distant control and survival, with similar chronic toxicity and sphincter preservation rate in rectal cancer patients.

Pre-treatment carcinoembryonic antigen and outcome of patients with rectal cancer receiving neo-adjuvant chemo-radiation and surgical resection: a systematic review and meta-analysis

Neo-adjuvant chemo-radiation is the standard of care for patients with locally advanced rectal carcinoma. The aim of the present paper is to evaluate the relationship of the baseline serologic concentration of the carcinoembryonic antigen with the outcome. Data sources included MEDLINE and Web of Science databases. A systematic search of the databases by a predefined criterion has been conducted. Chemo-radiation followed by surgical resection of rectal tumors was the intervention of interest. From selected studies, the relationships between carcinoembryonic antigen and pathologic complete response, disease-free survival and overall survival were assessed. Carcinoembryonic antigen correlated significantly and inversely with the rate of pathologic complete responses (OR 2.00). Similar to this relationship, a low baseline carcinoembryonic antigen concentration was associated with a better disease-free survival (OR 1.88) and a better overall survival (OR 1.85). Heterogeneity of studies and publication bias were considerable in evaluating the relationship of baseline carcinoembryonic antigen and pathologic complete response. Baseline carcinoembryonic antigen should be regarded as a predictor of outcome of patients undergoing neo-adjuvant chemo-radiation. A calibration of the cutoff value from 5 to 3 ng/ml appears more appropriate to this patient population and should be evaluated in prospective trials.

Can serum dynamics of carcinoembryonic antigen level during neoadjuvant chemoradiotherapy in rectal cancer predict tumor response and recurrence? A multi-institutional retrospective study

PURPOSE

We evaluate whether the change of carcinoembryonic antigen (CEA) level before and after preoperative chemoradiotherapy (CRT) in rectal cancer affects tumor response and recurrence or not.

METHODS

We retrospectively analyzed 1447 rectal cancer patients who underwent preoperative CRT followed by curative surgery. All patients received preoperative radiotherapy of 50.4 Gy in 28 fractions with 5-fluorouracil or capecitabine. Total mesorectal excision was performed 4 to 8 weeks after preoperative CRT. CEA levels were checked before and after CRT. Clinical and pathologic factors were analyzed for tumor response and recurrence.

RESULTS

Post-CRT CEA level (cutoff value, 2.5 ng/mL) was not a significant factor for tumor response on the multivariate analysis (p = 0.095). Patients were categorized according to the pre- and post-CRT CEA level (group A: pre-CRT CEA ≤5 ng/mL; group B: pre-CRT CEA >5 ng/mL and post-CRT CEA ≤2.5 ng/mL; group C: pre-CRT CEA >5 ng/mL and post-CRT CEA >2.5 ng/mL). The relapse-free survival (RFS) at 5 years was significantly higher in group A than in groups B and C (82.6 vs. 73.7 % vs. 72.2 %, p < 0.001). The overall survival (OS) at 5 years was significantly higher in group A than in groups B and C (90.1 vs. 84.4 % vs. 83.4 %, p < 0.001). However, there is no significant difference for RFS and OS between groups B and C (all, p > 0.05).

CONCLUSIONS

Decline of elevated CEA level (>5 ng/mL) during preoperative chemoradiotherapy has no significant effect on tumor response and recurrence in rectal cancer.

Significance of histologic tumor grade in rectal cancer treated with preoperative chemoradiotherapy followed by curative surgery: A multi-institutional retrospective study

BACKGROUND AND PURPOSE

To evaluate the pre-treatment clinical factors affecting recurrence and survival in rectal cancer patients who receive preoperative chemoradiotherapy (CRT) and curative surgery.

METHODS AND MATERIALS

The clinical data of 1782 patients from 8 institutions in Korea were analyzed. The potential prognostic factors that could be acquired before radical surgery were patient age, gender, clinical T and N stages, tumor size and location, tumor grade, carcinoembryonic antigen (CEA) level, and the concurrent chemotherapy regimen. The relapse-free survival (RFS), overall survival (OS), and cumulative incidence of locoregional and distant recurrence were analyzed according to the clinical factors.

RESULTS

Among the pre-treatment clinical factors, tumor grade, pre-CRT CEA level, tumor location, and clinical N stage were significant prognostic factors affecting the RFS. The high-grade tumor was the hazardous factor for RFS on the multivariate analysis [Hazard ratio (HR), 1.83; 95% confidence interval (CI), 1.29-2.58; p=0.001]. The 5-year RFS rate for high-grade tumors was significantly lower than that for low-grade tumors (63.8% vs. 78.8%, p<0.001). The tumor grade was a significant prognostic factor for distant recurrence (HR, 1.83, 95% CI, 1.29-2.58; p<0.001), but not for locoregional recurrence (HR, 1.49, 95% CI, 0.68-3.26; p=0.320) on the multivariate analysis. The 5-year OS rate for high-grade tumors was significantly lower than that for low-grade tumors (70.6% vs. 85.5%, p<0.001).

CONCLUSION

The tumor grade is the significant pre-treatment clinical factor for recurrence and survival in rectal cancer patients who receive preoperative CRT and curative surgery.