5242 - Differences in survival between right and left-sided colorrectal cancer (CRC) in every stage, a CARESS-CCR Group Study.

Background

Until now, we have managed all CRC patients (pts) in the same way, However, emergent data show that location of primary tumour can have a prognostic and predictive value in metastatic setting. In this study, we analized differences in sv for every stage between right (R) and left-sided (L) CRC.

Methods

This prospective, multicentre observational study was conducted in coordination with 22 public-sector hospitals of Spain. Pts diagnosed with new CRC, stage I-IV and surgically treated, were included. We defined R-CRC as tumours originated in cecum, ascending colon, hepatic flexure or transverse colon, and L in splenic flexure, descending and sigmoid colon or rectum.

Results

Data from 1742 pts were examined for sidedness, stage, and survival at 2 years. 509 (29.2%) had R and 1233 (70.8%) L-CRCs. Most of cases were non-metastatic (92.3%), and males (63.4%). At 2 years, 14.2% of R-CRCs and 15.8% of L-CRCs experienced a recurrence (p 0.408). Nevertheless, the survival analysis revealed a poorer outcome for R-CRCs, with less patients alive at 2 years: 86.6% (CI 95%:83.5 - 89.6) than L-CRCs: 92.4% (CI 95% 90.8 - 93.8); p < 0.001. The prognosis was significantly better for L-tumours in more advanced stages (III and IV), and in stage I as well. Patients with stage II seemed to have a very similar outcome, regardless their tumours were placed in right or left side. Only survival mean was slightly higher in R-CRCs, but percentage of survival at 2 years was the same for two both sides, without showing any statistical difference.Table:

594P Differences in survival between R-CRC and L-CRC in every stage

Conclusions

Overall, prognosis is better for L-tumours in every stage, most notably in advances stages (III-IV). However, stage II behaves in a distinct manner and no differences in survival are found between R-CRC and L-CRCs in these pts.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

REDISSEC.

Funding

REDISSEC (RD12/0001/0010), Fondo de Investigaciones Sanitarias (13/0013) and Fondo Europeo de Desarrollo Regional (FEDER).

Disclosure

All authors have declared no conflicts of interest.