Standardization of rectal cancer surgery and bowel preparation in Austria

Colorectal cancer (CRC) represents the third most common cancer worldwide [1]. In 2018, the incidence of CRC in Austria was 51.5 per 100,000 people, and the risk of developing CRC by the age of 75 years was 2.6%. Due to screening programs, a decrease in the incidence and mortality of CRC over the last 10 years has been observed [2].

The standard surgical treatment for rectal cancer is total mesorectal excision (TME), which results in a low incidence of local recurrence rates [3, 4]. The TME can be performed using the traditional open or minimally invasive approach, including laparoscopic, robotic and transanal techniques [5]. In a network meta-analysis, Ryan et al. found no significant differences in long-term oncological outcomes, with respect to local recurrence and survival, between all minimally invasive approaches [3].

In contrast to the traditional open surgery, the laparoscopic approach is associated with a significantly improved postoperative recovery, resulting in less pain and a shorter hospital time [6]. In comparison, the advantages of open TME were shorter operative times and more intact mesorectal specimens [6, 7]. Notably, laparoscopic TME is technically demanding, resulting in relatively high learning curves. Son et al. described a minimum of 60–80 cases to attain proficiency in conducting laparoscopic rectal resection [8]. Consequently, transanal TME (TaTME) and robotic TME have been introduced to overcome those limitations.

Patient outcome highly depends on the surgeon’s experience. Jimenez-Rodriguez et al. concluded that it was necessary to attain 21–23 cases in robotic rectal surgery to complete the learning curve [9]. Persiani et al. revealed longer learning curves for TaTME and recommended strict supervision for the first 40–50 cases [10]. In comparison, a systematic review by Burghgraef et al. showed that 32–75 cases were essential to complete the learning curve for robotic TME and 36–75 cases for TaTME [11]. Regarding Austria, it remains unknown how many rectal resections are conducted in each hospital per year and whether surgeons can achieve a sufficient number of resections to complete the learning curve and maintain a reasonable level of experience.

Bowel preparation to reduce postoperative morbidity represents another essential topic in colorectal surgery. Recent data from the American College of Surgeons National Surgical Quality Improvement Program suggested a potential role for either combined mechanical bowel preparation and preoperative oral antibiotics or oral antibiotics alone to lower the number of surgical site infections. Consequently, the American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Use of Bowel Preparation recommended the combined approach for elective colorectal surgery. In addition, multiple studies have revealed no benefit in mechanical bowel preparation alone [12, 13]; however, it remains unclear whether surgical units in colorectal surgery follow the new recommendations.

Thus, the present nationwide survey conducted by the Austrian Society of Surgical Oncology was designed to assess the surgical management of rectal cancer patients in Austria. Additionally, we evaluated the standard approach in bowel preparation in all centers in Austria performing elective colorectal surgery.

We enrolled 64 centers, with Lower Austria having the highest number of participating departments (n =15, 23%, followed by Vienna, n = 10, 16%), and Upper Austria (n = 9, 14%). In Styria eight (13%) departments participated and five each (8%) in Tyrol, Salzburg and Carinthia. The lowest numbers were recorded in Vorarlberg with three (5%) and Burgenland (6%) with four centers.

The purpose of this study was to describe the current clinical practice in Austria for standardized rectal cancer surgery. Additionally, we assessed whether bowel preparation before elective colorectal surgery reflected international recommendations for optimal patient care. We found that there are few well specialized rectal surgery centers in Austria, owing to the low number of low anterior resections performed in each hospital per year. Interestingly, a few hospitals named minimally invasive techniques such as TaTME or robotic surgery as their standard procedure for treating rectal cancer surgically. This is surprisingly taking into account that most departments perform two or three resections per year only. Given the estimated learning curves for TaTME (36–54 cases) and robotic surgery (32–75 patients), the question arises, whether the implementation in every center is reasonable and justified [11].

There has been clear evidence that the postoperative outcome after rectal resections also depends on the surgeon’s training, experience, and volume [14]. Aquina et al. indicated that the postoperative mortality and rate of permanent colostomies were significantly reduced by 57% and 35%, respectively, when rectal resections were performed in high-volume hospitals by high-volume surgeons. According to their definition, such dedicated hospitals undertook at least 25 rectal resections per year, and 1 surgeon conducted at least 10 rectal resections annually [15]. Ho et al. and Hodgson et al. revealed similar results. They demonstrated that patients who underwent rectal resection in specialized hospitals had decreased postoperative mortality and were less likely to obtain a permanent colostomy [16, 17]. In our study, 10 departments showed an annual number of 10 or fewer cases. Even surgeons with many years of experience need to achieve a certain number of procedures to maintain their surgical skills. Surgeons in training may not even complete an adequate number of operations to meet the learning curves.

Van Oostendorp et al. revealed that learning curves played a significant effect, especially for the first 10 operations, in which high rates of local recurrence and anastomotic insufficiency were noted. This was especially the case for novel techniques such as TaTME, where a substantial decrease in the local recurrence rates was observed after 40 procedures [18]. A study in Norway further questioned the safety of TaTME as they found unfavorable rates of local recurrence and anastomotic leakage compared to the Norwegian Colorectal Cancer Registry [19]. In line with other countries, Switzerland established centers for highly specialized medicine, where rectal resections are performed routinely. A caseload of at least 25 resections per year was defined as a cut-off number [20]. A study by Kaech et al. showed that this process of centralization had a positive effect on postoperative mortality [20].

The other main topic of our questionnaire addressed the standardization of bowel preparation regimens among Austrian hospitals. Notably, the majority of participating facilities (84%) reported using a standard preparation technique prior to elective colorectal resections; however, the protocols differed significantly between hospitals and were not always in line with current guideline recommendations. For example, mechanical bowel preparation alone for the right colon was conducted in 20% and for the left colon in 34%. Taking into account the current evidence, mechanical preparation alone is not suggested in colonic surgery, as a reduction in anastomotic leakage rates and surgical site infections was not observed in contrast to no preparation [13]. Interestingly, a European survey by Devane et al. revealed that mechanical bowel preparation alone was routinely prescribed by about 30% of the responders before colon surgery, which was similar to our results [21].

Several surveys [22‐24] showed similar results with infrequent use of oral antibiotics and regular use of mechanical bowel preparation, despite a significantly lower incidence of surgical site infections when using a combination of both [25]. On the contrary, data from the USA revealed a more common use of a combined preparation [26]. This was also in the line with the present results, where a combined preparation before rectal resection was observed in almost 50%.

There were a few limitations of the study that need to be addressed. First, although we provided a large number of participating departments, it does not include all hospitals in Austria. It is also worth mentioning that all numbers were individually entered and calculated by each participating hospital but were not confirmed by national statistics.

Considering the low number of anterior resections conducted in each hospital annually, specialized departments for rectal cancer surgery are still lacking in Austria. Notably, many hospitals did not follow guideline recommendations for bowel preparation routinely.