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

Abstract

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.

Prognostic impact of CEA levels in rectal cancer patients who had received neoadjuvant chemoradiotherapy

“…In non-nCRT group, the elevated CEA level after surgery is may be due to false positive. This finding has also been revealed in several existing literature [ 30 - 33 ]. Our results may be useful in predicting recurrence and establishing treatment strategies in rectal cancer patients who received nCRT, especially in patients with continuing CEA level elevation after surgery.…”

“…A r t i c l e [26][27][28][29][30]. Our findings may be due to persistence of micrometastases during nCRT and continued production of CEA as a result.…”

“…There may be tumor cells that have escaped systemic control while local control of tumor cells by nCRT. CEA reflects the burden of these circulating tumor cells and has been used as a marker for detecting micrometastases [ 26 - 30 ]. Our findings may be due to persistence of micrometastases during nCRT and continued production of CEA as a result.…”

Carcinoembryonic antigen BEFORE AND AFTER neoadjuvant chemoradiotherapy IN PREDICTION OF pathological complete response in patients with locally advanced rectal cancer

“…Ни нормализация РЭА (менее 5 нг/мл), ни снижение РЭА более 50 % от исходного не коррелировали с патоморфологическим ответом опухоли (p>0,13). Полученные результаты согласуются с данными Saito et al [16], которые также не обнаружили связи между нормализацией исходно повышенного РЭА после неоадъювантной химиолучевой терапии и степенью патоморфоза. Однако имеются другие исследования, в которых нормализация РЭА после неоадъювантной химиолучевой терапии чаще приводила к полному морфологическому ответу [10][11][12].…”

Abscopal Effects in Metastatic Cancer: Is a Predictive Approach Possible to Improve Individual Outcomes?

“…CEA is expressed as a non-specific tumor marker on the surface of many cancer cells, whereas CEA plasma levels are very faint (0 to 5 ng/mL). Increased CEA levels act as a determiner for the tumor stage and as a predictor of the response to therapy for gastric cancer [218][219][220]. In NSCLC, a CEA plasma level could be used as a prognostic marker for overall survival, recurrence or progression-free survival [221].…”