Reply to: doi:10.1007/s00464-010-1485-0: Evaluation of factors affecting the difficulty of laparoscopic anterior resection for rectal cancer: “narrow pelvis” is not a contradiction

Abstract

Following the widespread success of laparoscopic colon surgery, laparoscopy has now been used in the treatment of rectal cancer. It has shown to be feasible and oncologically safe in single-center series and in two randomized trials, but results from more statistically powered trials are needed. An intuitive feeling and the outcomes from initial clinical experiences suggest that rectal dissection is more difficult than colonic dissection. In rectal dissection, the patient’s anatomical and pathological characteristics need to be taken into account because they may influence the duration of the procedure, the conversion rate and the technical difficulty. Several studies have tried to identify the factors that may influence the outcome of laparoscopic rectal procedures, and BMI, tumor size, pelvis dimensions, and distance of the tumor from the anal verge seem to play a role [1–4]. Our group and others recently published several papers related to this topic. In a prospective series of 60 patients, we found that sex, BMI, smaller pelvis diameter, and tumor size were independent predictors for conversion, operative time, and morbidity [5–10]. These findings, however, were not replicated in a recent paper by Ogiso et al. [11]. We want to congratulate these authors for their fine results because they are much better than the average results in most series of rectal laparoscopy to date. They had no cases of conversion to open surgery, no deaths or positive circumferential margins, no need for temporary ileostomy, and only one anastomotic leakage. However, to explain these marked differences in results, we believe that several points in the Ogiso et al. study need to be analyzed: the form in which the data are presented, the distance from the tumor to the anal verge, and the transversal diameter of the tumor. First of all, Ogiso et al. present their data as median and first and third quartile values rather than as the conventional median and range or mean and standard deviation. These differences make it difficult to gain a clear idea of the range of measurements they provide in the series and even more difficult to compare them with previously published data. Another point of interest is that Ogiso et al. do not state specifically the distance from the anal verge to the tumor. In contrast, they do provide the anastomosis height from the anal verge. Also about this issue, it would be interesting to know why there is a notable difference between men and women. Why a high proportion of patients, 20 of 50, did not have a total mesorectal excision should also be clarified. To our minds, this suggests that the rectal transection was higher than expected. Rectum transection is substantially more difficult in lower tumors and may have played a role here. From the information given, the reader does not have a clear idea about the features of the specimen concerning distance of the tumor from the anal margin. The third point we would like to make refers to the transversal diameter of the tumor. In our experience, the length of the tumor was a factor with predictive value [10]. This difference may be related to the more frequent use of S. Fernandez-Ananin E. M. Targarona C. Balague C. Martinez P. Hernandez M. Trias Unit of Gastrointestinal and Hematological Surgery, Hospital de la Santa Creu i Sant Pau, Autonomous University of Barcelona, Barcelona, Spain