[Perioperative Outcome of Laparoscopic Surgery after Colonic Stent Placement for Obstructive Colorectal Cancer].

In recent years, bridge to surgery(BTS), in which surgery is performed after colorectal stenting for obstructive colorectal cancer, has gradually become popular, and laparoscopic surgery is also a treatment option. From January 2020 to December 2022, we retrospectively evaluated clinicopathological factors in 18 colorectal cancer cases who underwent radical resection after colorectal stenting. We found no difference in patient background, histopathological factors, primary anastomosis rate, stoma creation rate, operative time, postoperative complication rate and length of hospital stay between the laparoscopic surgery(L)and open surgery(O)groups. Blood loss was significantly lower in group L. In T4 patients, laparoscopic surgery after colorectal stenting can be safely performed, but conversion to open surgery may be necessary. Surgery after colorectal stenting should be performed based on preoperative accurate imaging and sufficient experience.

[A Case of Sigmoid Colon Cancer with Retroperitoneal Fibrosis Using Intraoperative Indocyanine Green Fluorescence Angiography for Colorectal Anastomosis].

A 72-year-old man was presented with anemia and diagnosed with sigmoid colon cancer by colonoscopy. CT showed a soft tissue density around the retroperitoneum, leading to the diagnosis of retroperitoneal fibrosis. Stenosis of left ureter, inferior mesenteric artery, and left colic artery due to the soft tissues were detected. Sigmoidectomy and retroperitoneal biopsy were performed, and colorectal anastomosis was completed after confirming the intestinal blood flow by ICG fluorescence angiography. In retroperitoneal fibrosis, identifying blood vessels intraoperatively can be difficult. ICG fluorescence angiography is useful for reliable anastomosis in colorectal cancer surgery with retroperitoneal fibrosis.

[A curative resection with the combination of portal vein branch embolization and systemic chemotherapy in a patient with synchronous multiple and bilobar colorectal liver metastases].

A 60-year-old man was admitted to our institution having a descending colon cancer with synchronous liver metastases. Tumor marker levels were remarkably elevated and the liver metastases were multiple and located at both right lobe and segment 4. Due to lack of the remnant liver volume, left hemicolectomy and intraoperative right portal vein branch embolization were performed as a primary operation. Three weeks after the operation, he started to undergo systemic chemotherapy by mFOLFOX6. After 8 courses of the treatment, grade 3 neurotoxicity appeared, and we changed the regimen to FOLFIRI. During a total of 18 courses of the chemotherapy, the periodic CT scans revealed the liver metastases to be PR or SD, and no other metastatic lesion was detected. After the rest of chemotherapy for 7 weeks, extended right hepatectomy was performed. He had an uneventful postoperative course and the tumor marker levels immediately returned to normal levels. He has been in good health without a recurrence for 10 months after hepatectomy. The combination of portal vein embolization and systemic chemotherapy may contribute to improve respectability of synchronous multiple and bilobar colorectal liver metastases.

Gender differences in pelvic anatomy and effects on rectal cancer surgery.

BACKGROUND/AIMS: The male pelvis is said to be narrower and deeper than the female pelvis. The present study aimed to evaluate anatomical differences in the pelvis between genders, and to analyze effects on rectal cancer surgery. METHODOLOGY: Gender differences in pelvic anatomy were evaluated using computed tomography in 78 Japanese patients who had received low anterior resection for rectal cancer. Factors affecting operative duration and intraoperative blood loss were analyzed for both low anterior resection and ultra-low anterior resection. RESULTS: Pelvic capacity was significantly lower in males (460.0 +/- 16.7 cm3) than in females (634.8 +/- 22.0 cm3; p < 0.0001), and level of the levator ani compared to the upper edge of the pubis was significantly lower in males than in females. Surgical parameters in ultra-low anterior resection were affected by level of the levator ani, tumor volume and tumor height compared to the upper edge of the pubis, not by tumor height above anal verge. CONCLUSIONS: The pelvis was narrower and deeper in males than in females. Obtaining good visualization is critical particularly in performing ultra-low anterior resection against a large tumor located below the upper edge of the pubis in a patient who has deep pelvic floor.

Laser Doppler assessment of the influence of division at the root of the inferior mesenteric artery on anastomotic blood flow in rectosigmoid cancer surgery.

AIMS: The aim of this study is to evaluate the influence of dividing the inferior mesenteric artery (IMA) and preserving the left colic artery (LCA) on rectosigmoid cancer surgery. PATIENTS AND METHODS: Colonic blood flow at the proximal site of the anastomosis was measured by laser Doppler flowmetry in 96 patients with cancer of the rectum and sigmoid colon while clamping IMA or LCA. Results were analyzed with patient characteristics and postoperative complications. RESULTS: Blood flow was significantly decreased by either IMA or LCA clamping, and its reduction rate was 38.5 +/- 1.8%, ranged from 0 to 82.8%, or 16.4 +/- 1.8%, ranged from 0 to 66.2%, respectively. For multivariate analyses, aging and male gender were predictive factors of high blood flow reduction by IMA clamping. The reduction rate was significantly correlated with aging in male patients, while no such correlation was observed in women. Aging correlation in men was more significant in ultralow anterior resection cases. Three elderly male patients received IMA high ligation among 19 patients who demonstrated more than 50% blood flow reduction by IMA clamping. Among these, two patients, those who underwent ultralow anterior resection, suffered severe anastomotic ischemia. CONCLUSIONS: Colonic blood flow at the proximal site of the anastomosis was significantly decreased by either IMA or LCA clamping. Patients with high reduction by IMA clamping need intraoperative efforts to prevent anastomotic ischemia, particularly in elderly male patients who undergo ultralow anterior resection.

Decreased interstitial cells of Cajal in the neorectum after anterior resection of the rectum.

BACKGROUND/AIMS: Patients who have undergone anterior resection for rectal carcinoma often complain of anorectal and defecatory dysfunction postoperatively. The aim of this study was to examine the expression of interstitial cells of Cajal (ICCs) in the sigmoid colon used for constructing the neorectum after anterior resection of the rectum. METHODOLOGY: As the neorectum group, we assessed 12 patients with local and anastomotic recurrence or new neoplasm in the neorectum after anterior resection of the rectum. The control group consisted of 16 patients who underwent sigmoid colon resection for sigmoid colon carcinoma. All resected specimens were investigated with immunohistochemical staining, using c-kit antibody for ICCs. The correlation between the number of ICCs and defecatory symptoms was assessed for the neorectum. RESULTS: The total number of ICCs significantly decreased in the neorectum group as compared to the control group. In particular, a significant difference was noted between the two groups as to the number of ICCs found between the layers of the myenteric plexus in histological studies, as well as in the circular and longitudinal muscles. There was no correlation between the number of ICCs and the time interval from the initial anterior resection to the resection of the neorectum, nor was there any relationship between the number of ICCs and defecatory symptoms. CONCLUSIONS: The expression of ICCs in the neorectum was reduced in the early stages after anterior resection of the rectum. Expression of ICCs in the neorectum did not recover to preoperative levels over time.

Assessment of rectal aberrant crypt foci by standard chromoscopy and its predictive value for colonic advanced neoplasms.

BACKGROUND AND AIMS: Aberrant crypt foci (ACF) are thought to be preneoplastic lesions and are assessed by magnifying chromoscopy with methylene blue staining. The aim of this study was to evaluate the predictive value of rectal ACF recognized by conventional chromoscopy for colonic advanced neoplasms. METHODS: Total colonoscopy, involving rectal chromoscopy using indigo carmine with standard colonoscopies, was performed on 386 patients. Patients who showed no ACF were classified as Grade 0, and those who had 1-4, 5-9, and 10+ ACF were classified as Grades 1, 2, or 3, respectively. The correlation between ACF grading and the prevalence of colonic advanced neoplasm, any adenoma>or=1 cm in size and/or with villous or tubulovillous morphology, and/or with high-grade dysplasia or invasive cancer, was assessed. RESULTS: Sixty-three patients were classified as ACF Grade 0, 119 as Grade 1, 116 as Grade 2, and 88 as Grade 3. Colonic advanced neoplasm was observed in 4 patients (6.3%) for Grade 0, 43 (36.1%) for Grade 1, 61 (52.6%) for Grade 2, and 57 (64.8%) for Grade 3. As the ACF grade increased, the chance of a patient having a colonic advanced neoplasm increased. For multivariate analyses, compared with patients with Grade 0, those with Grades 1, 2, or 3 had a greater risk of colonic advanced neoplasm (odds ratio [OR] 9.18, 95% CI 3.08-27.33, OR 20.44, 95% CI 6.81-61.42, and OR 32.94, 95% CI 10.49-103.41, respectively). CONCLUSIONS: Chromoscopic assessment of rectal ACF by conventional techniques is useful for predicting colonic advanced neoplasms.

Induction and recovery of colonic motility/defecatory disorders after extrinsic denervation of the colon and rectum in rats.

BACKGROUND: Anterior resection for rectal disease is associated with extrinsic autonomic denervation of the neorectum, which may influence the myenteric plexus, and subsequently the motility/defecatory status after operation. METHODS: A rat model with denervated neorectum was constructed. Colonic contractile activity in vivo, the amount of generic neuron marker (PGP 9.5) and nitric oxide synthase (NOS) were measured periodically. The responses of the muscle strip in each period to electrical field stimulation were evaluated using various neurotransmitters. RESULTS: In rats with denervated neorectum, giant migrating contractions (GMCs) of the distal colon, the number of fecal lumps per day and their small size, significantly increased in the early phase postoperatively, although both recovered in the late-phase period. The contractile response of the muscle strip of the denervated colon to acetylcholine was reduced throughout the period; however, contraction of the denervated colon under the addition of NO inhibitor (l-NAME) was enhanced significantly in the late-phase period, and recovered to the control level by atropine. Neuronal NOS, but not PGP 9.5 concentration, in the myenteric plexus at the distal denervated colon, significantly increased in the late-phase period. None of the above items differed from the control at other colonic portions throughout the period. CONCLUSIONS: Extrinsic autonomic denervation causes abnormal hyper-motility in the neorectum, which may be associated with multiple evacuations in the early phase postoperatively. Increased acetylcholine and the subsequent increase of neuronal NOS in the myenteric plexus may be an adaptive mechanism to compensate for such abnormal colonic motility after extrinsic denervation.

Denervation of the neorectum as a potential cause of defecatory disorder following low anterior resection for rectal cancer.

PURPOSE: The aim of this study was to determine whether denervation of the sigmoid colon during low anterior resection contributes to the postoperative motility characteristics of the neorectum and to the defecatory function of patients. METHODS: Sixty-seven patients who underwent either low or ultralow anterior resection for rectal cancer were evaluated. In accordance with the length of denervated neorectum, each patient was assigned to either the short-denervation or long-denervation group, determined by whether the inferior mesenteric artery was divided. Colonic propagated contraction was then measured by means of intraluminal pressure monitoring. Transit time was calculated with orally administered radiopaque markers. RESULTS: Propagated contraction down to the neorectum was significantly less common in the long-denervation group (14/36) than in the short group (12/15, P < 0.05), whereas spastic minor contraction at the neorectum was significantly more common in the long-denervation group (21/36) than the in short group (3/15, P < 0.05). Colonic transit time below the sigmoid colon was significantly longer in long group (6.4 hours) than in the short group (3.4 hours, P < 0.01). Although motility disorder of the neorectum was correlated with clinical defecatory malfunctions, including multiple evacuations, urgency, and soiling, no significant correlation was noted between the length of the denervated neorectum and the defecatory disorders. CONCLUSIONS: Motility of the neorectum following low anterior resection appears degraded by intraoperative maneuvers that cause denervation of the remnant sigmoid colon. Motility disorder of the neorectum, but not the length of the denervated neorectum causing the disorder, correlates well with several defecatory malfunctions. This finding suggests that postoperative defecatory disorder as a result of low anterior resection is caused by many factors in addition to denervation of the neorectum.

Defecatory malfunction caused by motility disorder of the neorectum after anterior resection for rectal cancer.

BACKGROUND: The correlation between postoperative defecatory status after anterior resection for rectal cancer and physiologic neorectal motility has not been well delineated. METHODS: Sixty patients who underwent anterior resection were examined. Motility of the neorectum was examined with 4-sensor intraluminal pressure monitoring, and segmental colonic transit time was determined with radiopaque Sitzmarks (Konsyl, Fort Worth, Texas) capsules. RESULTS: Twenty-eight patients experienced loss of propagated contraction waves down to the neorectum, which was closely correlated with a prolonged transit time through the neosigmoid colon and neorectum. In 26 patients, minor spastic waves were observed at the neorectum, which did not correlate well with the loss of propagated waves. The loss of propagation and the existence of spastic waves were significantly correlated with urgency of defecation and multiple evacuations. The latter was also associated with major soiling and with patients' assessments of impaired defecatory function. CONCLUSIONS: The physiologic motility of the neorectum is one of the factors responsible for postoperative defecatory function after anterior resection for rectal cancer.

[The effectiveness of prosthodontic mandibular advancement for obstructive sleep apnea syndrome].

PURPOSE: This study investigated the hypothesis of a direct association between the shift of incisal point and the diameter of the oropharynx space, and nocturnal oximetry with and without prosthodontic mandibular advancement (PMA) which is one type of oral appliance used to treat obstructive sleep apnea syndrome (OSAS), and to indicate the effects of PMA. METHODS: A total of 19 patients with OSAS were subjected to finger pulse oximetry recording and lateral cephalometric radiography: with and without PMA. The distance of the oropharynx space (PNS-AS, SPAS, MAS, and IAS) and the shift of incisal point with PMA were measured. The oxygen desaturation index (ODI 4%) and the cumulative percentages of time spent at saturations below 90% (CT(90)) during sleeping were calculated. Spearman's rank correlation test was used to measure the relationship between the increase of the velopharyngeal space and the distance of the mandible. The ODI 4%, CT(90) and distance of the velopharyngeal space were compared for all subjects with and without PMA by Wilcoxon's linking test. RESULTS: There was a strong relationship between the increase of the lower part (IAS) and the distance of anterior shift of incisal point (r=0.61, p=0.01). ODI 4% and CT(90) significantly decreased (p<0.01) and the three liners of the oropharynx(SPAS, MAS, IAS) significantly increased with PMA (p<0.01). CONCLUSIONS: It was shown that prosthodontic mandibular advancement could reduce the ODI 4% and CT(90) value in patients with OSAS, by enlarging the oropharynx space.