Ana Borda

Endoscopic localization of colorectal cancer: Study of its accuracy and possible error factors

INTRODUCTION accurate preoperative localization of colorectal cancer (CRC) is very important, with a wide range of published error rates. AIMS to determine accuracy of endoscopic localization of CRC in comparison with preoperative computed tomography (CT). To analyse variables that could be associated with a wrong endoscopic localization. PATIENTS AND METHODS endoscopic and CT localization of a series of CRC without previous surgery were reviewed. We studied the concordance between endoscopic and radiologic localization against operative findings comparing accuracy of endoscopy and CT. We analysed the frequency of wrong endoscopic diagnoses with regard to a series of patient, endoscopy and tumor variables. RESULTS two hundred thirty seven CRC in 223 patients were studied. Concordance with surgical localization was: colonoscopy = 0.87 and CT = 0.69. Endoscopic localization accuracy was:91.1%; CT: 76.2%: p = 0.00001; OR = 3.22 (1.82-5.72). Obstructive cancer presented a higher rate of wrong localization: 18 vs. 5.7% in non-obstructive tumors (p = 0.0034; OR = 3.65 (1.35-9.96). Endoscopic localization mistakes varied depending on tumor location, being more frequent in descending colon: 36.3%, p = 0.014; OR = 6.23 (1.38-26.87) and cecum: 23.1%, p = 0.007; OR = 3.92 (1.20-12.43). CONCLUSIONS endoscopic accuracy for CRC localization was very high and significantly better than CT accuracy. Obstructive tumor and those located in the descending colon or cecum wereassociated with a significant increase of the error risk of CRC endoscopic localization.

Influye el posible cansancio del endoscopista en la frecuencia de colonoscopias incompletas y de las lesiones polipoideas diagnosticadas

INTRODUCTION Nowadays, the possible effect of endoscopist fatigue on the results of colonoscopies is under discussion. We aimed to analyze possible differences in cecal intubation and the polyp and adenoma detection rate, depending on whether colonoscopies were performed at the beginning or at the end of the daily endoscopy session and to analyze the influence of the queue position on the detection rate. PATIENTS AND METHODS A retrospective study was performed with 1,000 ambulatory and consecutive colonoscopies, divided into 2 groups: «early» and «late» procedures. A total of 95 colonoscopies were excluded due to poor colon cleansing. After confirming that patient characteristics were homogenous in the two groups, we compared the frequency of complete colonoscopies and the polyp and adenoma detection rate. Possible differences between the 2 groups in the polyp detection rate according to the colonoscopy schedule were analyzed. RESULTS The overall polyp and adenoma detection rates were 44.2 and 30.5%, respectively, with no significant differences among 13 different endoscopists; polyps: p = 0.21; adenomas: p=0.63. No significant differences were found between the «early group» (n= 532) and the «late group» (n = 373) in the rates of complete colonoscopies [97.2 vs 99.4% (p=0.92)], the polyp detection rate [45.9 vs 41.8% (p=0.23)], the adenoma detection rate [30.8 vs 30% (p=0.80)] or the serrated adenoma rate [2.1% vs 1.6% (p=0.62)]. The lesion detection rate did not vary in relation to the «queue position»: polyps [p = 0.60, and adenomas: p = 0.83. CONCLUSIONS In our series, endoscopist fatigue at the end of the day had no influence on the complete colonoscopy rate or on the polyp and adenoma detection rate. There were no differences in the number of polypoid lesions detected according to the timing of the colonoscopy schedule.

Lesiones neoplásicas sincrónicas en el cáncer colorrectal. Análisis de posibles factores que favorezcan su presentación

Aim: few data have been published regardingthe causes of synchronous lesionsinpatientswith colorectal cancer.The aim of our study was to identifypotentialfactors that mightbe implicated in the development of multicentric lesions, since this knowledge could be useful for tailored follow-up once initial synchronousle sions havebeenremoved. Methods: we retrospectively reviewed 382 colorectal cancer cases diagnosedby total colonoscopy and histological study of surgical specimens. We divided our population into 2 groups, based on whether they had synchronous lesions or otherwise. Several data related to personal and family history, habits, symp toms, and tumor characteristics were assessed. Univa riate and multivariate statistical analyseswere performed. Results: 208 (54.5%) patients had synchronous adenomas and 28 (7.3%) had synchronouscancer. A multivariate analysis showed that the followingparameters were consistently related to the presence of multicentriclesions –male gender:OR = 1.97; CI = 1.13-3.45; p = 0.017; age ≥ 59 years: OR = 2.57; CI = 1.54-4.29; p < 0.001; personal history of colonic adeno mas: OR = 3.04; CI = 1.04-8.85; p = 0.042; and obstructivetu mors: OR = 0.48; CI = 0.27-0.85; p = 0.012 . Conclusion: our results show that severalparameters that are easy to measure could be considered risk factors for the develop ment of multicentric lesions. These factors need to be confirmed with follow-up studies analyzingtheir role in patients with and without metachronic lesions once all synchronous lesions have beenremoved.

Sa1908 Onodera Index Independently Predicts Survival in Surgically Treated Colorectal Carcinoma

INTRODUCTION: Onodera index (OI) combines circulating lymphocytes and albumin levels. It has been used as a nutritional and immunological marker and it has been recently proposed in Eastern literature its possible value as a predictive variable of prognosis in colorectal cancer (CRC). AIMS: To analyse the prognostic value of OI, assessed at initial diagnosis, on survival of patients with resected CRC. PATIENTS AND METHODS: We present a retrospective observational study including 207 consecutive patients with CRC and surgically treated on elective basis. Clinical follow-up was performed, documenting all cases of tumor-related deaths. OI was calculated according to the equation: [10 x serum albumin (g/dl) + 0.005 x circulating lymphocytes/mm2]. OI values 6 mcg/l, OI < 40 and OI ≥ 40. Univariant and multivariant analysis were performed [Cox model, stepwise, determining hazard ratio (HR) and 95% confidence interval (CI 95%)]. Finally, Fisher and square chi tests were used to compare 5-year mortality rates between groups with OI < 40 and OI ≥ 40, calculating odds ratio (OR) and CI. RESULTS: 26 patients (12.6%) presented a low OI. Median follow up was 81 months, with an interquartile range of 60-96. Overall tumor-related mortality was 23.7% and 19.8% 5 years after surgery. Variables with independent prognostic value in multivariant analysis are summarised in the following table below. 5-year mortality rate was significantly higher in patients with low OI: 42.3% vs 16.7% [OR = 3.69; CI = (1.42-9.58); p=0.002]. CONCLUSIONS: 1. A low Onodera index, assessed at initial CRC diagnosis, is associated with a worse survival curve after tumor resection. 2. This negative prognostic significance of an Onodera index < 40 has proved to have an independent predictive value. 3. Post-surgery 5-year mortality is higher in patients with a low Onodera index. Variables with independent prognostic value in multivariant analysis

ESTUDIO DEL INTERVALO DIAGNÓSTICO DE LAS SUCESIVAS GENERACIONES DE ADENOMAS METACRÓNICOS EN EL CARCINOMA DE COLON Y RECTO

Introduccion Un elevado porcentaje de canceres colo-rectales (CCR) desarrollan adenomas metacronicos. Son escasos los trabajos que analizan el periodo de tiempo transcurrido entre la reseccion del tumor y el diagnostico de las sucesivas generaciones de adenomas metacronicos. Objetivos Estudiar la evolucion del tiempo hasta el diagnostico en las sucesivas generaciones de adenomas metacronicos. Comparar la latencia diagnostica de la primera lesion metacronica entre los pacientes con y sin lesiones sincronicas previas. Material y metodos Analizamos 382 CCR, seguidos mediante colonoscopias completas. Determinamos el tiempo transcurrido entre la reseccion del cancer inicial y el diagnostico de la 1 a , 2 a y 3 a generacion de adenomas metacronicos. Comparamos las posibles diferencias en cuanto a tiempo hasta el diagnostico del primer adenoma metacronico entre los casos con y sin lesiones sincronicas iniciales. Para el estudio estadistico empleamos el test de Mann Whitney, considerando significativos los valores de p Resultados 208/382 pacientes (54,5%) presentaron adenomas sincronicos y 162 (42,4%) desarrollaron adenomas metacronicos. La media de colonoscopias de control ha sido de 2,74±1,75 por paciente. La mediana del tiempo (meses) de las sucesivas colonoscopias fue 1 a =15; 2 a =32; 3 a =46; 4 a =63; 5 a =72; 6 a =85; 7 a =93 y 8 a =100 meses. Las medianas del tiempo hasta el diagnostico para la 1 a generacion de adenomas metacronicos fueron de 21 meses, reduciendose a 16 para la 2 a generacion y 14 meses para la 3 a . En los pacientes con adenomas sincronicos, la primera lesion metacronica se diagnostico significativamente antes: mediana=19 meses con respecto a los que no tenian lesiones sincronicas: mediana=30 meses (p=0,011). Conclusiones 1. El intervalo hasta el diagnostico de las lesiones metacronicas se va reduciendo progresivamente en las sucesivas generaciones de adenomas. 2. El tiempo transcurrido hasta el diagnostico del primer adenoma metacronico es significativamente menor en los canceres colo-rectales con adenomas sincronicos iniciales. 3. Nuestros resultados aconsejan efectuar el primer control endoscopico de forma mas precoz en los pacientes que hubieran presentado previamente adenomas sincronicos.

T1091 Synchronous Neoplastic Lesions in Colorectal Cancer. Analysis of Possible Risk Factors Favouring Presentation

Aim: few data have been published regardingthe causes of synchronous lesionsinpatientswith colorectal cancer.The aim of our study was to identifypotentialfactors that mightbe implicated in the development of multicentric lesions, since this knowledge could be useful for tailored follow-up once initial synchronousle sions havebeenremoved. Methods: we retrospectively reviewed 382 colorectal cancer cases diagnosedby total colonoscopy and histological study of surgical specimens. We divided our population into 2 groups, based on whether they had synchronous lesions or otherwise. Several data related to personal and family history, habits, symp toms, and tumor characteristics were assessed. Univariateand multivariate statistical analyses were performed. Results: 208 (54.5%) patients had synchronous adenomas and 28 (7.3%) had synchronouscancer. A multivariate analysis showed that the followingparameters were consistently related to the presence of multicentriclesions –male gender:OR = 1.97; CI = 1.13-3.45; p = 0.017; age ≥ 59 years: OR = 2.57; CI = 1.54-4.29; p < 0.001; personal history of colonic adeno mas: OR = 3.04; CI = 1.04-8.85; p = 0.042; and obstructivetu mors: OR = 0.48; CI = 0.27-0.85; p = 0.012. Conclusion: our results show that severalparameters that are easy to measure could be considered risk factors for the develop ment of multicentric lesions. These factors need to be confirmed with follow-up studies analyzingtheir role in patients with and without metachronic lesions once all synchronous lesions have beenremoved.