Clinical: Therapy & observation S259 is still unclear. Administration of melatonin can be one of the new therapeutic options in the treatment of UC. Methods: Double-blind, multicenter, randomized clinical study in 62 patients with mild and moderate UC in acute phase of disease was performed. Clinical severity of UC was based on Mayo score assessment. Endoscopic (EI) and histological (HI) indexes were evaluated. Bioptates of the colon mucosa were stained by haematoxylin-eosin, alcian blue at pH 1.0 and 2.5, PAS-reaction. Melatonin containing EC-cells were identified by Sevka’s method. Immunohistochemistry was performed using monoclonal mouse antibodies raised against the mucins (Muc2, Muc3, Muc4), trefoil factor-3 (TFF3) and CD3, CD20, CD34, CD68. All patients received standard treatment of UC (5-ASA, topical steroids) during 30 days. 32 patients were treated with melatonin (2 mg per day orally) in addition to the base therapy (1st group). 30 patients who didn’t receive melatonin were considered as a 2nd group. Results: Before the therapy total Mayo index in all UC patients’s group consisted 7.6+0.9 score points. The severity of UC correlated with the extensive of inflammation in the large intestine. The level of staining of Muc2 and Muc3 in all patients with UC was low, up to its complete absence (59.2% and 53.1% cases, p = 0.05). Muc4 and TFF3 had high and medium staining intensity. Low quantity of EC-cells in the colon mucosa was found. After the treatment the most pronounced improvement was found in patients who received melatonin in addition to the standard treatment. Clinical remission was achieved earlier in the 1st group (day 12.2+4.1) with Mayo index 1.9+0.5 score points in contrast to the 2nd group: remission on 18.3+7.2 days, index Mayo 2.7+0.8 (p = 0.05). The significant evidence of mucosal healing was mentioned in patients with melatonin: EI 1.1+0.5, HI 1.8+0.8, which were accompanied with increasing of Muc2 and Muc3 production (up to 75% cases), quantity of EC- cells, changes of CD3, CD20, CD34, CD68 in the colon mucosa. Conclusions: Melatonin application in addition to the standard treatment of UC was more effective than standard therapy alone. Melatonin showed significant improvement in the course of disease, earlier achievement of remission phase, evidence of deep histological remission in patients with UC. P462 Influence of immunosuppressant treatment on the development and progression of neoplasms in patients with inflammatory bowel disease G. Ontanilla Clavijo*, E. Leo Carnerero, C. Trigo Salado, M.D. De La Cruz Ramirez, A. Araujo Miguez, J.M. Herrera Justiniano, J.L. Marquez Galan. HU Virgen del Rocío, UGC Digestive Diseases, Seville, Spain Background: To understand the incidence of neoplasms of any type in patients with inflammatory bowel disease (IBD) as well as the relationship with immunomodulating and biological treatments on their risk and progression. Methods: Retrospective analysis that includes 510 patients with IBD: 328 Crohn’s disease (CD), 172 ulcerative colitis (UC) and 10 indeterminate colitis (IC), with the latter two considered as a single entity. We collect demographic characteristics, tobacco and alcohol use, phenotypic characteristics of IBD, use of immunosuppres- sants (IS) (azathioprine (AZA), methotrexate (MTX), anti-TNF agents) in monotherapy or concomitantly. Although we record all neoplasms that develop at any point in life, we perform the analysis on all those detected once the patient was diagnosed with IBD. Results: The age at diagnosis of IBD was 31.3 years and the follow-up time was 9.69 years; 277 patients (54.3%) had been smokers at some time during their life, while excessive alcohol consumption was found in 37 (7.3%) patients. In CD, use of some type of IS treatment was prescribed in 248/328 patients (76%), while in UC-IC group it was 68/182 (37.3%). In both cases, AZA was the most widely-used drug (242 CD and 65 UC-IC). MTX was used in 41 CD and 9 UC-IC, infliximab in 79 and 27 patients and adalimumab in 66 and 5, respectively. At least two concomitant IS agents were used in 111/510 patients (21.8%). Five patients had neoplasm prior to IBD diagnosis. After IBD diagnosis, 23 neoplasms (4.5% of patients) were diagnosed. Among the factors analyzed, we only found alcohol to be a risk factor for the development of neoplasm (5/37 [13.5%] vs. 18/473 [3.8%], p = 0.02). Patients treated with an IS agent at any time developed neoplasms after the diagnosis of IBD in 12/316 (3.3%) vs. 11/194 (5.7%) of cases never treated with IS (p = 0.3) regardless of the type of IS used or whether combined therapy was used at any time (3/111 [2.7%]) or not (20/399 [5%]). When IS treatment was discontinued, IBD remained inactive in 2/7 cases while there was recurrence in the remaining 5 (one of whom required surgery) after a two- year follow-up period. Nevertheless, the mean age at diagnosis of the neoplasm was lower in patients treated with IS (46.5 vs. 58 years, p = 0.06). After a mean follow-up of 3.13 years, mortality due to neoplasm in patients on IS treatment was 25% (3/12) vs. 9% (1/11) in patients who did not receive IS. Conclusions: The use of IS drugs does not promote the development of neoplasms, even with combined therapy. However, when neoplasms do appear they are more aggressive since they occur at earlier ages and are associated with a higher short-term mortality rate due to the neoplasm. P463 Infliximab use in ulcerative colitis from 2003 to 2013: Clinical practice, safety and efficacy L. Fern´ andez-Salazar 1 *, J. Barrio 2 , C. Mu˜ noz 3 , J. Legido 4 , G. Gonz´ alez 1 , R. S-Oca˜ na 2 , F. Santos 2 , B. Velayos 1 , J.M. Gonz´ alez 1 . 1 Hospital Clínico Universitario, Gastroenterology, Valladolid. ACAD, Spain, 2 Hospital Universitario Río Hortega, Gastroenterology, Valladolid, Spain, 3 Hospital Virgen de la Salud, Gastroenterology, Toledo. ACAD, Spain, 4 Complejo Asistencial de Segovia, Gastroenterology, Segovia. ACAD, Spain Background: Infliximab (IFX) was approved in 2006 for the treatment of ulcerative colitis (UC) unresponsive to other therapies. We want to describe our current practice in treating UC with IFX with special attention to some topics as cotreatment with immunosuppressant agents, intensification, IFX response, and colectomy rates. Methods: This is a multicentric and retrospective study which collects clinical data from UC patients teated with IFX in four Spanish hospitals from June 2003 to September 2013. Results: 88 UC patients (age 35 years (SD 14.8), 42% females, E1 12%, E2 27%, E3 60%) were treated with IFX during 25 (SD 22) months. 83% received intravenous steroids at least once and 80% were treated with thiopurines before IFX. Thiopurines were stoped because of intolerance in 45% and because of resistance in 50%. 7% received methotrexate, 18% cyclosporine or tacrolimus and 21% were treated with leukocyto-apheresis. Time from UC diagnosis to infliximab was 8.8 (SD 6.9) years. IFX was decided because: steroid resistance 27%, intolerance/ resistance to steroids or immunosuppressant agents 38%, steroid dependence 30%, pouchitis 2%, extraintestinal mani- festations 1%. 5 mg/kg (0 2 and 6 weeks) induction dose was programmed for 98% of patients but the third dose was finally 10 mg/kg in 7%. Steroids were used with infliximab induction in 78%. Mantainment (5 mg/kg every 8 weeks) was scheduled in 92% of patients (42% with clinical remission after induction, 39% with clinical response after induction and 10% with no response to induction). 75% of patients received thiopurines (63% since more than 6 months before IFX induction, 14% since less than 6 months before induction, 14% since induction, 6% Downloaded from https://academic.oup.com/ecco-jcc/article-abstract/8/Supplement_1/S259/369540 by guest on 03 June 2020