Surgical Strategy for Rectovaginal Fistula After Colorectal Anastomosis at a High-volume Cancer Center According to Image Type and Colonoscopy Findings

Patients and Methods

This retrospective study included 11 patients who developed rectovaginal fistula after colorectal anastomosis. Out of 1,455 surgical cases, 9 (0.62%) underwent resection for a primary rectal lesion at the Department of Gastroenterological Surgery, Aichi Cancer Center Hospital between July 2004 and June 2018 (14 years). Two cases underwent resection for a primary rectal lesion at other hospitals in the same period. This research project was approved by the Ethics Committee of our institution (2019-1-034) and conformed to the provisions of the Declaration of Helsinki.

Rectovaginal fistula was classified into four types according to diagnostic contrast enema images and colonoscopy findings, i.e., “Alone type” (n=7, 63.6%), “Dead space type” (n=1, 9.1%), “Anastomotic stricture type” (n=1, 9.1%), and “Dead space and Anastomotic stricture type” (n=2, 18.2%).

“Alone type” was defined as the presence of a rectovaginal fistula without dead space or an anastomotic stricture (Figure 1). “Dead space type” was defined as the presence of a rectovaginal fistula with dead space (Figure 2). “Anastomotic stricture type” was defined as the presence of a rectovaginal fistula with an anastomotic stricture (Figure 3). “Dead space and Anastomotic stricture type” was defined as the presence of a rectovaginal fistula with an anastomotic stricture and dead space (Figure 4). All cases showed eventually complete healing.

Figure 5 shows the surgical strategy for rectovaginal fistula in our hospital. In all 4 types, “Diversion (Stoma)” was initially selected, with the expectation of complete healing. In the absence of complete healing in a “Dead space type” case, “Percutaneous drainage” was then selected. In “Anastomotic stricture type” cases, “Endoscopic balloon dilation” was initially selected. In “Dead space and Anastomotic stricture type” cases, “Percutaneous drainage” and “Endoscopic balloon dilation” were initially selected, with subsequent conversion to “Alone type” and the expectation of complete healing. In further absence of complete healing, “Curettage of foreign bodies”, “Simple full-thickness closure”, “Split-thickness closure” and “Pedicled flaps packing” were selected. “Curettage of foreign bodies” was used to treat infected granulation tissue or staple pins (Figure 6). “Simple full-thickness closure” was used to treat rectovaginal fistula involving the posterior vaginal wall and anterior rectal wall as a unit. “Split-thickness closure” was used to treat rectovaginal fistula with involvement of the anterior rectal wall in a horizontal direction. The vaginal wall was then closed vertically at right angles to the rectal wall or closed vertically in parallel with the rectal wall (Figure 7).

In further absence of complete healing without evidence of local relapse, “Reanastomosis” was selected. “Diversion (Stoma)” was ultimately required for closure.

The surgical strategy appropriate for each rectovaginal fistula type was investigated. Rectovaginal fistulas were grouped into two categories, i.e., “Alone type” and all other types: “Dead space type”, “Anastomotic stricture type” and “Dead space and Anastomotic stricture type”. Similarly, the surgical strategies were grouped into two categories, i.e., “only Diversion (Stoma)” and all other strategies: “Curettage of foreign bodies (infected granulation tissue, staple pins, etc.)”, “Simple full-thickness closure”, “Split-thickness closure (vaginal wall at right angles with the rectal wall and vaginal wall in parallel with the rectal wall)”, “Pedicled flaps packing,” and “Reanastomosis”.

Analyses were performed using the Chi-square test. Statistical significance was set at p<0.05.