Can the POLARS tool accurately predict low anterior resection syndrome in rectal cancer patients undergoing laparoscopic resection?

Introduction: Radical rectal cancer resection can lead to a long-term bowel function impairment known as low anterior resection syndrome (LARS). It remains unclear how to determine which patients are at a higher risk of developing LARS post-surgery. The POLARS tool was designed to predict the onset and severity of LARS in rectal cancer patients after surgery. The study aimed to assess the accuracy of POLARS in predicting the onset of LARS. Material and methods: A total of 66 rectal cancer patients treated laparoscopically between January 2016 and December 2017 were included in this retrospective study. Using POLARS, the predictive value for the occurrence of LARS was documented. During an average 17-month follow-up period, the bowel function of the patients was assessed using the dedicated LARS questionnaire. The predicted and actual scores were then compared. Results: Study participants included 36 women (54.5%) and 30 men (45.5%), with a mean age of 62.55 years (standard deviation: 10.2; range: 37-81). The mean predicted score according to POLARS was 24.5 (i.e. category "minor LARS"), and the mean actual score in the follow-up period was 16.42 ("no LARS" category). In only 39% of patients, the predicted LARS category was the same as the actual LARS category assessed by the questionnaire. Worse bowel function than reported at follow-up was predicted in 75% of all mispredictions. Conclusions: POLARS did not prove to be accurate in predicting the risk and severity of LARS in these patients, although the average numbers appear promising. Further evaluation of the POLARS tool using a larger cohort is needed.