For nearly half a century, desmoid tumor (DT) has been considered a major complication that occurs in approximately 10%-25% of familial adenomatous polyposis (FAP) patients. It is also the leading cause of death in patients undergoing colectomy. We believe that the mortality rate is improving due to the understanding of the natural history of DT and recent advances in medical treatment. The risk factors of DT development include trauma, having a distal germline APC variant, having a family history of DTs, and estrogens. In the era of minimally invasive surgery, several reports demonstrated no significant difference in both surgical approach (laparoscopic vs. open) and surgical procedure (ileal pouch-anal anastomosis vs. ileorectal anastomosis). Regarding the treatment of FAP-associated DT, rapidly proliferating and life-threatening intra-abdominal DT accounts for approximately 10% of FAP-associated DT; however, it has been shown that it can be controlled by identifying and introducing cytotoxic chemotherapy. Moreover, tyrosine kinase inhibitors and γ-secretases, which are used to treat sporadic DT, which is more frequent than FAP-associated DT, are expected to be effective. In the future, such treatment is expected to further reduce the mortality rate from DT associated with FAP. In addition to the conventional staging of intra-abdominal DT, the classification proposed in Japan was recently thought to be useful for the treatment strategy of FAP-associated DTs. In this review, we summarize the recent advances and current management for the FAP-associated DT, including recent data from Japan.

Rectovaginal fistula (RVF) is a challenging complication with unsatisfactory success and a significant burden for the patients. With insufficient clinical data due to the rare entity, the present state of treatments for RVFs was reviewed especially form the point of factors to determine management, classifications, principle of treatment, conservative and surgical treatments with outcomes. Size, fistula localization and etiology, type of fistula; "simple" or "complex," status of anal sphincter complex and surrounding tissue, presence or absence of inflammation, presence of diverting stoma, previous attempted repair and radiation therapy, patient's condition with co-morbidities, and surgeon's experience are important factors to determine the management of RVF. The inflammation should initially subside in cases with infection. Starting with conservative surgical options and interposing healthy tissue for complex or recurrent fistulas, invasive procedures will be performed if conservative treatment failed. Conservative treatment may be effective in RVFs with minimal symptoms and should be done for small RVFs for a 36 months usual period. Anal sphincter damage might need a repair of sphincter muscles along with RVF repair. Diverting stoma can initially be constructed in patients with severe symptoms and larger RVFs to relief the patient's pain. Simple fistula is usually indicated for local repair. Local repairs to transperineal and transabdominal approaches can be used for complex RVFs. Interposition of healthy, well-vascularized tissue can be required for more complex fistulas and abdominal procedures for high RVFs.

Objectives: The geriatric nutritional risk index (GNRI) is a nutrition-related risk index calculated easily from serum albumin and the ratio of body weight to ideal body weight. We investigated the prognostic values of the GNRI in elderly patients with obstructive colorectal cancer (OCRC) who had a self-expandable metallic stent inserted as a bridge to curative surgery.

Methods: We retrospectively evaluated 61 patients aged ≥65 years with pathological stage I to III OCRC. Associations of preoperative GNRI and pre-stenting GNRI (ps-GNRI) with short- and long-term outcomes were examined.

Results: Multivariate analyses revealed GNRI of <85.3 and ps-GNRI of <92.9 were independently associated with worse cancer-specific survival (CSS; P = 0.016, and P = 0.041, respectively), and overall survival (OS; P = 0.020, and P = 0.024, respectively). A ps-GNRI of <92.9 was correlated with poorer relapse-free survival (RFS) only in the univariate analysis (P = 0.034). For the OCRC cohort without age restriction (n = 86), GNRI of <85.3 and ps-GNRI of <92.9 were independently associated with worse CSS (P = 0.021), and OS (P = 0.023), respectively. In univariate analysis, ps-GNRI of <92.9 was significantly correlated with poorer RFS (P = 0.006). Moreover, ps-GNRI of <92.9 was significantly associated with Clavien-Dindo grade of ≥III postoperative complications (P = 0.037), anastomotic leak (P = 0.032), infectious complications (P = 0.002), and longer postoperative hospital stay (17 days vs. 15 days; P = 0.048).

Conclusions: In OCRC patients, decreased preoperative and pre-stenting GNRI were significantly correlated with poorer survival, and decreased pre-stenting GNRI was significantly associated with worse short- and long-term outcomes.

Objectives: Anorectal sensation is an essential component for maintaining normal defecation and continence. This study aimed to investigate changes in anorectal sensation with age and sex using the anorectal sensory threshold to electrical stimulation in a large population with a broad age spectrum.

Methods: This study enrolled consecutive adult patients (20-89 years old) who underwent anorectal physiology tests to screen for functional or organic anorectal disease. Anorectal sensitivity was measured using an endoanal electrode with a 45-mm long bipolar needle. A constant electrical current was delivered to the lower end of the rectum and the anal canal. The minimum current in milliamperes at which the initial sensation was felt was defined as the sensory threshold.

Results: Overall, 888 patients were included in this study. The most frequent comorbidities were constipation and hemorrhoids. The median sensory threshold for all patients was 0.5 (interquartile range, 0.2-1.5) mA, and the overall sensory threshold was significantly higher in men than in women. The 95% confidence interval of the sensory threshold for men and women were 0.1-6.8 and 0.1-5.1 mA, respectively. The sensory threshold increased significantly with age in both sexes (men, r = 0.384; women, r = 0.410). There was no sex difference in the sensory threshold between ages 20 and 40 years; however, between ages 50 and 70 years, men had a higher sensory threshold than women.

Conclusions: The anorectal sensory threshold to electrical stimulation increased with age, and the influence of aging was more significant in men than in women.

Objectives: Preventing anastomotic complications during rectal cancer surgery is important. Compared with a manual circular stapler, a powered circular stapler is expected to reduce undesirable tension during anastomosis. However, whether a powered circular stapler can reduce anastomotic complications during robotic low anterior resection (Ro-LAR) remains unclear. We aimed to investigate whether the use of a powered circular stapler contributes to safe anastomosis in Ro-LAR.

Methods: A total of 271 patients who underwent Ro-LAR for rectal cancer between April 2019 and April 2022 were included. Depending on the type of device employed, patients were divided into a powered circular stapler group (PCSG) and a manual circular stapler group (MCSG). Clinicopathological features and surgical outcomes were compared between the two groups.

Results: There were no differences in clinicopathological characteristics and surgical outcomes, except for anastomotic outcomes, between the two groups. Patients with positive air leak tests were significantly more in the MCSG (p=0.026; PCSG, 1.5%; MCSG, 8.0%). Frequencies of anastomotic leakage (p=0.486; PCSG, 6.1%; MCSG, 8.9%) and anastomotic bleeding (p=1.000; PCSG, 0.7%; MCSG, 0.8%) were similar between the two groups. Multivariate analysis showed that the use of a powered circular stapler significantly increased the negative leak tests (p=0.020, odds ratio 6.74, 95% confidence interval 1.35-33.56).

Conclusions: Use of a powered circular stapler in Ro-LAR for rectal cancer was significantly associated with a negative air leak test, suggesting that it contributes to stable and safe anastomosis.

Objectives: This study aimed to compare the short and long-term outcomes of cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy and resection of isolated peritoneal metastases in patients with peritoneal metastases from colorectal cancer in Japan.

Methods: We included patients who had undergone surgery for peritoneal metastases from colorectal cancer between 2013 and 2019. Data were retrieved from a prospectively maintained multi-institutional database and retrospective chart review. Patients were classified into cytoreductive surgery and resection of isolated peritoneal metastases groups based on the surgery they had undergone.

Results: A total of 413 patients were eligible for analysis (257 and 156 patients in the cytoreductive surgery and resection of isolated peritoneal metastases groups, respectively). There was no significant difference in overall survival (hazard ratio and 95% confidence intervals, 1.27 [0.81, 2.00]). Six cases (2.3%) of postoperative mortality were observed in the cytoreductive surgery group, whereas none were observed in the resection of the isolated peritoneal metastases group. Cases of postoperative complications were significantly higher in the cytoreductive surgery group (risk ratio 2.02 [1.18, 2.48]) than those in the resection of isolated peritoneal metastases group. Among patients with a high peritoneal cancer index (6 points or higher), the complete resection rate was 115/157 (73%) and 15/44 (34%) in the cytoreductive surgery and the resection of isolated peritoneal metastases groups, respectively.

Conclusions: Cytoreductive surgery was not superior in providing long-term survival benefits for colorectal cancer peritoneal metastases; however, cytoreductive surgery provided a higher complete resection rate even in patients with a high peritoneal cancer index (6 points or higher).

Objectives: There are many surgical options for the treatment of rectal prolapse. To date, the efficacy of mesh-free laparoscopic suture rectopexy remains unclear due to the limited number of reports. This study aimed to evaluate the safety and efficacy of laparoscopic suture rectopexy.

Methods: This observational cohort study is a retrospective cross-sectional analysis of a continuously maintained database. All patients underwent laparoscopic suture rectopexy for rectal prolapse between April 2012 and March 2018. The primary outcomes measured were recurrence rates and complications of laparoscopic suture rectopexy.

Results: A total of 268 patients (29 male and 239 female) underwent laparoscopic suture rectopexy. Their mean age was 77 (19-95) years, and the mean prolapse length was 6.4 (3.5-20) cm. One patient suffered an intraabdominal abscess. Spondylitis developed in another patient following surgery. The median follow-up period was 45 (12-82) months. A total of 22 patients (8.2%) developed recurrence. The average time to recurrence was 15.6 (1-44) months. Multivariate analysis revealed a significant correlation between recurrence and prolapse length >7.0 cm (OR: 1.26, 95% CI: 1.38-1.42, P < 0.01).

Conclusions: Laparoscopic suture rectopexy for complete rectal prolapse is a minimally invasive and safe procedure that may lead to lower recurrence rates.

Objectives: This study aims to clarify the appropriate follow-up period after aluminum potassium sulfate and tannic acid (ALTA) sclerotherapy for internal hemorrhoids by transanal ultrasonography.

Methods: Forty-four patients (98 lesions) who underwent ALTA sclerotherapy were analyzed. Transanal ultrasonography was performed pre and post-ALTA sclerotherapy to observe the thickness and the internal echo image of hemorrhoid tissue. Patients who developed complications were excluded.

Results: No recurrence in 12 months was observed in 44 patients.

After 1-3 months of ALTA sclerotherapy, hemorrhoids were observed in the low-echo imaging region. During this period, hemorrhoidal tissue was observed thickest by granulation. Moreover, hemorrhoid tissue contracted by fibrosis formed 5-7 months post-ALTA sclerotherapy, with a thinner hemorrhoid. Furthermore, hemorrhoids hardened and regressed with intense fibrosis 12-months after the therapy and eventually became thinner than pre-ALTA sclerotherapy.

Conclusions: After ALTA sclerotherapy, the suggested follow-up period with and without the development of complications is ~6 and ~3 months, respectively.

Juvenile polyposis syndrome (JPS) is a rare disease characterized by multiple hamartomatous polyps within the gastrointestinal tract. SMAD4 or BMPR1A is known as a causative gene of JPS. Approximately 75% of newly diagnosed cases have an autosomal-dominantly inherited condition, whereas 25% are sporadic without previous history of polyposis in the family pedigree. Some patients with JPS develop gastrointestinal lesions in childhood and require continuous medical care until adulthood. JPS is classified into three categories according to phenotypic features of polyp distributions, including generalized juvenile polyposis, juvenile polyposis coli, and juvenile polyposis of the stomach. Juvenile polyposis of the stomach is caused by germline pathogenic variants of SMAD4 with a high risk leading to gastric cancer. Pathogenic variants of SMAD4 are also associated with hereditary hemorrhagic telangiectasia-JPS complex, inducing regular cardiovascular survey. Despite growing concerns regarding the managing JPS in Japan, there are no practical guidelines. To address this situation, the guideline committee was organized by the Research Group on Rare and Intractable Diseases granted by the Ministry of Health, Labor and Welfare involving specialists from multiple academic societies. The present clinical guidelines explain the principles in the diagnosis and management of JPS with three clinical questions and corresponding recommendations based on a careful review of the evidence and involve incorporating the concept of the Grading of Recommendations, Assessment, Development, and Evaluation system. Herein, we present the clinical practice guidelines of JPS to promote seamless implementation of accurate diagnosis and appropriate management of pediatric, adolescent, and adult patients with JPS.

Objectives: The present study aimed to investigate the clinical relevance of lateral pelvic lymph node dissection (LPLND) in low rectal cancer without preoperative treatment, with a focus on the presence of LPLN enlargement in preoperative imaging.

Methods: Consecutive patients with cT3 to T4 low rectal cancer who underwent mesorectal excision and LPLND without preoperative treatment between 2007 and 2018 at a single dedicated cancer center were included. LPLN short-axis diameter (SAD) measured using preoperative multi-detector row computed tomography (MDCT) was evaluated retrospectively.

Results: A total of 195 consecutive patients were analyzed. Overall, 101 (51.8%) and 94 (48.2%) patients had visible and no visible LPLNs in preoperative imaging, including 56 (28.7%), 28 (14.4%), and 17 (8.7%) patients had SADs of <5 mm, 5-7 mm, and ≥7 mm, respectively. Incidence of pathologically confirmed LPLN metastasis were 18.1%, 21.4%, 28.6%, and 52.9%, respectively. Overall, thirteen (6.7%) patients developed local recurrence (LR), including one patient who developed lateral recurrence, yielding a 5-year cumulative risk for LR of 7.4%. Five-year RFS and OS for all patients were 69.7% and 85.7%, respectively. No differences were observed in the cumulative risk for LR and OS between any pairs of groups.

Conclusions: No significant difference was observed in the cumulative risk for LR and OS regardless of LPLN SAD, implying the good impact of LPLND on the prevention of lateral recurrence, as well as the difficulty of predicting LPLN metastasis using only LPLN SAD in preoperative imaging.

In our previous report, we have noted an increase of computed tomography (CT) attenuation values in perirectal fat tissue after Gant-Miwa-Thiersch (GMT) procedure for rectal prolapse. Based on these results, we hypothesized that the GMT procedure may have a rectal fixation effect due to inflammatory adhesions extending to the mesorectum. Herein, we report a case of laparoscopic observation of perirectal inflammation after GMT. A 79-year-old woman with a history of seizures, stroke, subarachnoid hemorrhage, and spondylosis underwent the GMT procedure under general anesthesia in the lithotomy position for rectal prolapse measuring 10 cm in length. But rectal prolapse recurred 3 weeks after surgery. Therefore, an additional Thiersch procedure was performed. However, rectal prolapse still recurred, and laparoscopic suture rectopexy was performed 17 weeks after initial surgery. During rectal mobilization, marked edema and rough membranous adhesions were observed in the retrorectal space. The average CT attenuation value obtained 13 weeks after initial surgery was found to be significantly elevated in the mesorectum compared with the subcutaneous fat, especially in the posterior side (P < 0.05). These findings suggest that the extension of inflammation to the rectal mesentery after the GMT procedure may have strengthened adhesions in the retrorectal space.