Prognosis Can Be Predicted More Accurately Using Pre- and Postchemoradiotherapy Carcinoembryonic Antigen Levels Compared to Only Prechemoradiotherapy Carcinoembryonic Antigen Level in Locally Advanced Rectal Cancer Patients Who Received Neoadjuvant Chemoradiotherapy

Biomarkers in Locally Advanced Rectal Cancer: A Review

Locally advanced rectal cancers (LARC) are the subject of a rapidly evolving treatment paradigm. The critical timepoints where management decisions are required during the care of the LARC patient are: prior to the institution of any treatment, post neoadjuvant therapy and post-surgery. This article reviews the clinical, imaging, blood-based, tissue-based, and molecular biomarkers that can assist clinicians at these timepoints in the patient's management, in prognosticating for their LARC patients or in predicting responses to therapy in the multi-modality neoadjuvant treatment era.

Prognostic value of FDG PET-CT in suspected recurrence of colorectal carcinoma: survival outcomes of a 10-year follow-up : FDG PET in recurrent colorectal CA

OBJECTIVE

We aimed to evaluate the predictive value of FDG PET-CT scan and CEA measurements in recurrent colorectal cancer (CRC) patients.

METHODS

The records of 211 CRC patients who had FDG PET-CT scans between April 2009 and June 2011 due to suspicion of recurrence were extracted from the data of our previous report of 235 patients after 24 patients were excluded from the study due to lack of follow-up data or death unrelated to CRC. FDG PET-CT findings, simultaneous CEA levels, and survival data were evaluated retrospectively to determine the prognostic factors that affected the overall survival (OS) of the patients.

RESULTS

The mean age of 211 patients was 60.2 ± 12.8 years. The median follow-up time was 39 months (CI 95%: 4-123 months). The CRC-related death rate was 71.6% and the median OS time was measured 39 months (CI 95%: 27-50 months) for 211 patients. The median OS time for the patients with positive findings for recurrence in PET scans was 28 months (CI 95%: 22-33 months) which was significantly shorter (p < 0.001) than that of PET-negative patients (median OS was not reached; mean OS: 105 months; CI 95%: 95-116 months). CEA positivity also had a significant negative effect on survival (p < 0.001). Median OS times in patients with elevated and normal levels of CEA were 24 months (CI 95%: 17-30 months) and 85 months (CI 95%: 62-107 months), respectively. When the effect of CEA positivity was evaluated in patients with negative PET scans for recurrence, no statistically significant difference was determined (p = 0.209), but PET positivity had a significant negative effect on OS in patients with normal levels of CEA (p < 0.001). On the other hand, PET negativity had a significant positive effect on OS in patients with elevated CEA levels (p = 0.002). The extend of recurrent disease had also a significant effect on OS. The patients with distant metastasis had less favorable OS than those patients with only local recurrence (p < 0.001). The presence of liver metastasis also diminished the OS, but this effect was not statistically significant (p = 0.177).

CONCLUSION

FDG PET-CT scan which is a reliable imaging method to detect recurrence in CRC patients, regardless of CEA levels, can also provide valuable prognostic information, even superior to that of CEA measurement.

CEA Decline Predicts Tumor Regression and Prognosis in Locally Advanced Rectal Cancer Patients with Elevated Baseline CEA

Purpose: To investigate the value of carcinoembryonic antigen (CEA) decline in predicting pathological tumor regression and outcome for locally advanced rectal cancer (LARC) patients who received neoadjuvant therapy with elevated baseline CEA.

Methods: LARC patients with elevated pre-treatment CEA who received neoadjuvant therapy and radical tumor resection were retrospectively collected. Serum CEA level during treatment were recorded and the predictive value of pre-treatment CEA, post-treatment CEA and CEA ratio (CEA^{post-treatment} /CEA^{pre-treatment}) for tumor regression grade (TRG), overall survival and diseases free survival were estimated by logistic regression or cox proportional hazard regression.

Results: Two hundred and eighty-four LARC patients with elevated pre-treatment CEA were enrolled and the baseline, post-treatment CEA level and CEA ratio were 11.87 (5.02-731.31) ng/ml, 4.23 (0.50-173.80) ng/ml and 0.31(0.01-2.55) respectively. CEA level in 59.2% of the patients declined to normal after neoadjuvant therapy. Multivariate analysis showed that CEA ratio was an independent predictor for TRG (OR=3.463, 95% CI: 1.269-9.446, P=0.015) and tumor downstage (OR=0.393, 95% CI: 0.187-0.829, P=0.014). Patients with normalized post-treatment CEA level had better overall survival (P=0.010) and disease free survival (P=0.003) than those with elevated CEA level. Higher post-treatment CEA was an independent unfavored predictor for overall survival in LARC patients with elevated pre-treatment CEA (OR=1.042, 95% CI: 1.017-1.067, P=0.001).

Conclusion: Post/pre-treatment CEA ratio predicted tumor regression in term of TRG and tumor downstage for LARC patients with elevated pre-treatment CEA and higher post-treatment CEA predicted poor overall survival.

Neoadjuvant Modified FOLFOX6 With or Without Radiation Versus Fluorouracil Plus Radiation for Locally Advanced Rectal Cancer: Final Results of the Chinese FOWARC Trial

PURPOSE

In the multicenter, open-label, phase III FOWARC trial, modified infusional fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) plus radiotherapy resulted in a higher pathologic complete response rate than fluorouracil plus radiotherapy in Chinese patients with locally advanced rectal cancer. Here, we report the final results.

METHODS

Adults ages 18 to 75 years with stage II/III rectal cancer were randomly assigned (1:1:1) to five cycles of infusional fluorouracil (leucovorin 400 mg/m², fluorouracil 400 mg/m², and fluorouracil 2.4 g/m² over 48 hours) plus radiotherapy (46.0 to 50.4 Gy delivered in 23 to 25 fractions during cycles 2 to 4) followed by surgery and seven cycles of infusional fluorouracil, the same treatment plus intravenous oxaliplatin 85 mg/m² on day 1 of each cycle (mFOLFOX6), or four to six cycles of mFOLFOX6 followed by surgery and six to eight cycles of mFOLFOX6. The primary end point was 3-year disease-free survival (DFS).

RESULTS

In total, 495 patients were randomly assigned to treatment. After a median follow-up of 45.2 months, DFS events were reported in 46, 39, and 46 patients in the fluorouracil plus radiotherapy, mFOLFOX6 plus radiotherapy, and mFOLFOX6 arms. In each arm, the probability of 3-year DFS was 72.9%, 77.2%, and 73.5% (P = .709 by the log-rank test), the 3-year probability of local recurrence after R0/1 resection was 8.0%, 7.0%, and 8.3% (P = .873 by the log-rank test), and the 3-year overall survival rate was 91.3%, 89.1%, and 90.7% (P = .971 by log-rank test), respectively.

CONCLUSION

mFOLFOX6, with or without radiation, did not significantly improve 3-year DFS versus fluorouracil with radiation in patients with locally advanced rectal cancer. No significant difference in outcomes was found between mFOLFOX6 without radiotherapy and fluorouracil with radiotherapy, which requires additional investigation of the role of radiotherapy in these regimens.

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.