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21062 Background: EGFR is a protooncogen that facilitates metastasis in cancer. It is overexpressed in colorectal carcinoma in 40% to 80%, and correlates a worse prognosis. Aim: To find patterns of EGFR overexpression in NMCC and to correlate these patterns with the follow-up. Methods: We analized NMCC with a selection criteria: 1. primary adenocarcinoma of the colon, without metastasis and with curative surgery, 2. pT3 pN0–2 pM0, progression-free in the first 6 months postsurgery, 3. initial follow-up began 6 months postsurgery, 4. minimum follow-up over 5 years. Dako PharmaDx kit (Glostrup, Denmark) was used for immunohistochemical study for EGFR. Dako staining and A431-AAM cells were used as positive control. Immunoreactivity for membrane (1(+), 2(+) and 3(+) intensity) and for cytoplasma was evaluated. Proportions of immunostained cells were also assessed. Results: 195 patients (p) were eligible. Year of diagnosis: 1994: 1p; 1995: 4p; 1996: 20p; 1997: 29p; 1998: 33p; 1999: 36p; 2000: 34p; 2001: 38p. Male/female: 93/102; Mean age: 71 years (28- 94). Location: 116/79 left/right. Stage II/III: 125/70. EGFR membrane positivity: 84/195 cases (43%), 49/125 (39%) in Stage II and 35/70 (50%) in Stage III. With a median follow-up of 7 years: Stage II: 29/125 relapsed (EGFR±: 12(24%)/17(22%)). Stage III: 33/70 relapsed (EGFR± : 21(60%)/12(34%)). EGFR membrane positivity was a poor prognostic factor with a significant progression-free survival (PFS) (p=0.042) and a non-significant overall survival (OS) (p=0.066). When follow-up period was increased over 10 years (patients from 1994 to 1998), EGFR membrane positivity maintained its poor prognostic factor in PFS (p=0.009) and presented a significant OS (p=0.02). Non-significant differences were found in immunostaining ratios. Conclusions: In patients with non-metastatic colon cancer, EGFR membrane positivity was a tumor progression prognostic factor, and this poor prognosis was maintained over time. Study supported by a grant from C.I.R. Hospital de Sabadell. Consorci Sanitari Parc Taulí. Sabadell and a grant from Merck Laboratory. No significant financial relationships to disclose.