181P - Initial CEA and CA19-9 level were associated with pathologic outcome of locally advanced rectal cancer after neoadjuvant chemotherapy with or witho...

Date 17 December 2016
Event ESMO Asia 2016 Congress
Session Poster lunch
Topics Cytotoxic agents
Biomarkers
Rectal Cancer
Surgical oncology
Presenter JianWei Zhang
Citation Annals of Oncology (2016) 27 (suppl_9): ix53-ix67. 10.1093/annonc/mdw581
Authors J. Zhang1, Y. Cai1, H. Hu1, J. Xiao1, J. Ling1, Z. Wu2, Y. Deng1
  • 1Department Of Medical Oncology, The Sixth Affiliated Hospital of Sun Yat-sen University, 510655 - Guangzhou/CN
  • 2Medical Oncology, The Sixth Affiliated Hospital of Sun Yat-sen University, 510655 - Guangzhou/CN

Abstract

Background

Fluorouracil based chemoradiotherapy was the standard treatment for locally advanced rectal cancer. Due to the low incidence of local failure with total mesorectal excision and the severity damage of radiotherapy, we aimed to find out the subgroup of rectal cancer patients who might omit radiotherapy, for whom, preoperative enhancement chemotherapy was sufficient.

Methods

From Jan 2011 to Feb 2015, complete data was available for 309 patients with rectal cancer who received neoadjuvant chemotherapy with or without radiotherapy followed by TME enrolled in FOWARC study. According to the initial level of CEA and CA19-9, patients were categorized into 3 groups: Group A (high CEA and high CA19-9); Group B (high CEA or CA19-9); Group C (low CEA and CA19-9). The pathological complete response (pCR) rate, tumor downstaging rate (ypStage 0-I) and the tumor regression grade (TRG) among each group were analyzed basing on different preoperative treatment (chemoradiotherapy vs. chemotherapy).

Results

Among 309 patients, there were 24, 96 and 189 patients in group A, B and C, respectively. In group A, 14 patients received CRT and 10 patients had CT. The pCR rate was 7.1% vs. 0 (p = 0.38) and the downstaging rate (ypStage 0-I) was 21.3% vs. 30.0% (p = 0.63), the TRG 0-1 was 64.3% vs. 40.0% (p = 0.24), respectively. In group B, 69 patients underwent CRT and 27 had CT. The pCR rate was 21.7% vs. 14.8% (p = 0.44), the downstaging rate was 33.3% vs. 40.7% (p = 0.49) and the TRG 0-1 was 47.8% vs. 25.9% (p = 0.0503). While in group C, 109 patients received CRT and 80 patients underwent CT. The pCR rate was 26.6% vs. 6.3% (p = 0.0003), and the downstaging rate was 55.1% vs. 41.2% (p = 0.06). The TRG 0-1 was 66.1% vs. 36.2% (p = 0.00004).

Conclusions

Preoperative radiotherapy seem to be insensitively to patients with high initial level of CEA and/or CA19-9. The pathological outcome was similar between CRT group and CT group. While in patients with normal CEA and CA19-9, radiotherapy was much more important. The pathological outcome was much better in the group of CRT than that of CT group.

Clinical trial indentification

NCT01211210

Legal entity responsible for the study

N/A

Funding

N/A

Disclosure

All authors have declared no conflicts of interest.