PURPOSE: To investigate the efficacy of intralesional 20% aspirin injection for treatment of experimental peritoneal endometriosis. Methods: Peritoneal endometriosis was experimentally induced in forty adult nulligravid female rabbits. On day 30 post-endometriosis induction, rabbits were randomly divided to assess early (10 days) and late (20 days) effects of intralesional injection of physiological saline solution (control groups) in comparison to intralesional injection of 20% bicarbonate aspirin solution (experimental groups) as follows: control group 1 (10 days, n=10); control group 2 (20 days, n=10); experimental group 3 (10 days, n=10); experimental group 4 (20 days, n=10). Resected tissues, including endometriosis foci, were qualitatively (general morphology and signs of inflammatory cells infiltrate, necrosis and apoptosis) and quantitatively (remaining endometriosis area) assessed by histopathological analysis. Results: Extensive necrosis, hemorrhage, apoptosis, and fibrosis were observed in the experimental groups 3 and 4. Groups 1 and 2 presented typical endometrial tissue cysts, respectively. Groups 3 and 4 showed sparse endometrial tissue foci and no endometrial tissue, respectively. Quantitative analysis revealed that aspirin-treated groups 3 and 4 had significantly (p<0.05) smaller remaining endometriosis area, compared to control groups 1 and 2. Conclusion: Intralesional 20% aspirin injection caused total destruction of peritoneal endometriosis foci in rabbits.

INTRODUÇÃO: A recidiva local no câncer colorretal tem como principal causa o implante de células tumorais nas anastomoses. 11-15 Dessa maneira, lavagem química do lúmen intestinal é preconizada para evitar tanto o implante quanto à recidiva local. 11-28 Em estudos prévios constatamos que a solução bicarbonatada de ácido acetilsalicílico tem efeitos citolíticos e anti-tumorais in-vitro.31 OBJETIVOS: Avaliar a toxicidade da solução de aspirina na mucosa colônica de coelhos com o objetivo de usá-la no preparo intestinal de portadores de câncer colorretal. MATERIAIS E MÉTODOS: Foram utilizados 20 coelhos. Um clampe vascular foi colocado acima do cólon sigmóide. Os animais foram submetidos a um enema com 50 ml da solução de aspirina ou soro fisiológico de acordo com o grupo. Os animais foram sacrificados ao término do procedimento ou tardiamente de acordo com o grupo. RESULTADOS: A solução de aspirina não altera a mucosa colônica de coelhos. CONCLUSÃO: O uso da solução bicarbonatada de ácido acetilsalicílico no preparo intestinal de portadores de câncer colorretal é clinicamente possível.

BACKGROUND: The implantation of viable exfoliated intraluminal tumour cells is the major cause of local recurrence in colorectal cancer. 11-28 Therefore, the bowel lumen wash with a tumoricidal agent has been recommended. 11-28 In previous study we observe that acetylsalicylic acid solution cause neoplastic cell death in vitro.31 PURPOSE: Assess the local effect of acetylsalicylic acid solution on the colonic mucosa of rabbits, in order to use this agent in the bowel lumen wash. METHODS: 20 rabbits were used. A vascular clamp was placed on the distal colon, followed by the instillation per rectum of 50 ml of acetylsalicylic acid solution or saline solution, according to the group. The euthanasia was performed immediately or later according to the group. RESULTS: The acetylsalicylic acid solution doesn't cause any injury on the colonic mucosa of rabbits. Conclusion: The use of acetylsalicylic acid solution in the bowel lumen wash seems clinically feasible.