Pathological impact of transanal colorectal tube for obstructive colorectal cancer

Colorectal cancer (CRC) with acute colorectal obstruction (ACO) is an emergency. Transanal colorectal tube (TCT) use can be a safe single-stage surgery with laparoscopy-assisted colectomy; it offers long-term outcomes equivalent to emergency surgery for stage-II/III CRC with ACO. Self-expanding metallic stent use, another alternative, may have detrimental pathological and molecular effects, whereas the pathological impact of TCT placement remains unclear. We hypothesized that TCT placement might exert little damage on primary tumor. Hence, the current study analyzed the pathological impact of TCT placement for CRC with ACO compared to emergency surgery. Data from consecutive patients with stage-II/III distal CRC with ACO who underwent surgery between January 2007 and December 2015 were retrospectively reviewed at two Japanese affiliate hospitals. Inflammatory and malignant potential-related parameters were analyzed by a single blinded pathologist. We extracted mRNA from tumor tissues to analyze inflammatory cytokines. Sixty-eight patients with stage-II/III distal CRC with ACO were identified (surgery: 25 patients; TCT: 43 patients). Baseline characteristics were well balanced between the two groups. TCT showed a significantly lower frequency of abscess (surgery vs TCT, 36.0% vs 11.6%; P = 0.017) and a lower tendency of pathological perforation (surgery vs TCT, 20.0% vs 4.7%, respectively; P = 0.091), compared to the surgery group. There were no significant intergroup differences in oncological factors, including perineural invasion (surgery vs TCT, 52.0% vs 62.8%; P = 0.383), microlymphatic involvement (surgery vs TCT, 52.0% vs 58.1%; P = 0.623), and microvascular involvement (surgery vs TCT, 32.0% vs 25.6%; P = 0.570). No significant intergroup differences were found in interleukin (IL)-6, IL-8, or IL-1β gene expression levels (P = 0.580, 0.250, 0.941). TCT placement had no pathologically detrimental effects on the tumor or surrounding tissues and might be an attractive non-invasive strategy for cases of curative distal CRC with ACO.