Carbohydrate antigen 19-9 plus carcinoembryonic antigen for prognosis in colorectal cancer: An observational study.

AIM: Carcinoembryonic antigen (CEA) is a primary prognostic marker and can detect colorectal cancer (CRC) recurrence; however, it has low sensitivity. Carbohydrate antigen 19-9 (CA 19-9) can be used as a supplemental tumour marker along with CEA. The purpose of this study was to determine whether preoperative CA 19-9 added to CEA helped predict long-term prognosis and whether follow-up CA 19-9 added to CEA had additional benefits in diagnosing the recurrence of CRC. METHOD: We retrospectively assessed patients who underwent surgery for primary CRC between January 2004 and December 2015 at Seoul National University Hospital. Data on demographics, preoperative and follow-up CEA and CA 19-9 levels, recurrence and survival were obtained and analysed with respect to tumour marker levels to ascertain their prognostic and diagnostic values. RESULTS: A total of 4972 and 1530 patients were included to analyse preoperative and follow-up tumour marker levels, respectively. The 5-year relapse-free survival rates were 72.2% ± 0.8%, 52.5% ± 2.2%, 55.5% ± 3.2% and 32.1% ± 2.3% in the normal CEA and CA 19-9, high CEA, high CA 19-9, and high CEA and high CA 19-9 groups, respectively (all P < 0.001). Patients whose elevated CEA or CA 19-9 levels reduced to normal levels had better survival outcomes than those with postoperatively elevated levels. Elevated follow-up CA 19-9 and CEA levels were related to higher incidences of distant metastasis (CA 19-9, 14.0% vs. 23.1%, P = 0.004; CEA, 12.6% vs. 30.1%, P < 0.001) but not to local recurrence. Combined follow-up CEA and CA 19-9 increased the sensitivity for recurrence to 31.4%, with a 5% difference from the sensitivity of CEA alone. In the subgroup with high preoperative CA 19-9 levels, sensitivity increased by 18.2% overall. CONCLUSION: CA 19-9 is a valuable prognostic and diagnostic marker for CRC when used adjunctively with CEA and can be a supplementary marker with CEA to improve sensitivity, especially with elevated preoperative CA 19-9.

Coring-out fistulectomy for perianal cryptoglandular fistula: a retrospective cohort study on 20 years of experience at a single center.

Purpose: Cryptoglandular fistula is one of the common anal diseases requiring surgical treatment. Various surgical techniques have been introduced; however, there is no known standard technique. Coring-out fistulectomy is a surgical technique that accurately resects only the fistula tract. However, only a few cases of this procedure have been reported. We aimed to analyze the surgical outcomes of coring-out fistulectomy for cryptoglandular anal fistulas. Methods: We retrospectively reviewed the medical records of patients who underwent coring-out fistulectomy for a cryptoglandular fistula between 1999 and 2019. Primary outcomes were the treatment success rate (recurrence and healing rates) and incidence of fecal incontinence. Results: A total of 184 patients were included in our study. The average age of the patients was 44 years (range, 16-75 years), and 88.0% were male. Twenty-four (13.0%), 13 (7.1%), and 68 patients (37.0%) underwent operation for recurrent fistula, multiple tracts, and complex type fistula, respectively. The healing rate was 92.4%, and recurrence occurred in 15 of 170 healed patients (8.8%). Thus, the treatment success rate was 84.2%. There was no fecal incontinence except in 1 patient who had preoperative fecal incontinence because of cauda equine syndrome. In multivariable analysis of the factors affecting the treatment success rate, the complex fistula (odds ratio [OR], 14.2; 95% confidence interval [CI], 4.7-43.0; P < 0.001) and undetected internal opening during the operation (OR, 4.0; 95% CI, 1.4-11.6; P = 0.012) were significant factors. Conclusion: Coring-out fistulectomy is a simple and feasible technique for sphincter-preserving anal fistula surgery.

Two dominant patterns of low anterior resection syndrome and their effects on patients' quality of life.

To identify low anterior resection syndrome (LARS) patterns and their associations with risk factors and quality of life (QOL). This cross-sectional study analyzed patients who underwent restorative anterior resection for left-sided colorectal cancer at Seoul National University Hospital, Seoul, Republic of Korea. We administered LARS questionnaires to assess bowel dysfunction and quality of life between April 2017 and November 2019. LARS patterns were classified based on factor analyses. Variable effects on LARS patterns were estimated using logistic regression analysis. The risk factors and quality of life associated with dominant LARS patterns were analyzed. Data of 283 patients with a median follow-up duration of 24 months were analyzed. Major LARS was observed in 123 (43.3%) patients. Radiotherapy (odds ratio [OR]: 2.851, 95% confidence interval [95% CI]: 2.504-43.958, p = 0.002), low anastomosis (OR: 10.492, 95% CI: 2.504-43.958, p = 0.001), and complications (OR: 2.163, 95% CI: 1.100-4.255, p = 0.025) were independently associated with major LARS. LARS was classified into incontinence- or frequency-dominant types. Risk factors for incontinence-dominant LARS were radiotherapy and complications, whereas those for frequency-dominant LARS included low tumor location. Patients with incontinence-dominant patterns showed lower emotional function, whereas those with frequency-dominant patterns showed lower global health QOL, lower emotional, cognitive, and social functions, and higher incidence of pain and diarrhea. Frequency-dominant LARS had a greater negative effect on QOL than incontinence-dominant LARS. These patterns could be used for preoperative prediction and postoperative treatment of LARS.

ERRATUM: Correction of Figure 1: Outcomes of surgical treatments for rectovaginal fistula and prognostic factors for successful closure: a single-center tertiary hospital experiences.

[This corrects the article on p. 149 in vol. 97, PMID: 31508396.].

Impacts of anemia and transfusion on oncologic outcomes in patients undergoing surgery for colorectal cancer.

PURPOSE: This study aimed to evaluate the prevalence of preoperative anemia and impacts of anemia and transfusion on survival in patients undergoing surgery for colorectal cancer. METHODS: This study included patients who underwent surgery for primary colorectal cancer between 2011 and 2012. The influence of preoperative anemia and postoperative transfusion on recurrence-free survival and overall survival were retrospectively investigated. Anemia was defined as hemoglobin level < 13 g/dL in males and < 12 g/dL in females. The primary outcome was the prevalence of preoperative anemia in patients with colorectal cancer. Secondary outcomes included preoperative anemia management, postoperative 30-day mortality and morbidity, tumor recurrence, and overall survival. RESULTS: Among a total of 1899 patients, 823 patients (43.3%) were anemic preoperatively, and 264 patients (13.9%) received postoperative transfusions. Postoperative transfusion was associated with 30-day postoperative complications (OR = 1.514, 95% CI = 1.020 ~ 2.247) but not preoperative anemia (OR = 1.143, 95% CI, 0.811 ~ 1.611). Preoperative anemia (HR = 1.459, 95% CI = 1.104 ~ 1.929) and postoperative transfusion (HR = 1.566, 95% CI = 1.089 ~ 2.252) were significantly associated with worse recurrence-free survival in multivariable analysis. Preoperative anemia (HR = 1.572, 95% CI = 1.274 ~ 1.940) and postoperative transfusion (HR = 1.381, 95% CI = 1.076 ~ 1.773) were significant independent risk factors for worse overall survival. CONCLUSIONS: Preoperative anemia and postoperative transfusion were associated with worse survival in patients undergoing surgery for colorectal cancer. An alternative therapy to treat anemia and reduce transfusions should be introduced to improve oncologic outcomes.

Preoperative Colonoscopic Tattooing Using a Direct Injection Method with Indocyanine Green for Localization of Colorectal Tumors: An Efficacy and Safety Comparison Study.

Purpose: Endoscopic tattooing is used to mark colorectal lesions for subsequent surgery. As a tattooing agent, India ink has been widely used but is not currently available in Korea. Indocyanine green (ICG) can be applied as an alternative agent. However, studies on colonoscopic tattooing by the direct injection of indocyanine green are lacking. This study aimed to compare the efficacy and safety between an ICG direct injection method and an India ink saline test injection method. Methods: A total of 227 patients who underwent preoperative endoscopic tattooing for colorectal neoplasm (149 patients in the ICG direct injection group and 78 patients in the India ink saline test injection group) were included in the study. The efficacy of the two methods was compared by visualization and safety was compared by evaluating the perioperative tattooing complications. Results: The visualization of lesions in the ICG group was not different from that of the India ink group (p=0.42, 96.0% vs 98.7%, respectively). Only one patient in the ICG group had abdominal pain related to tattooing, but no complications developed in the India ink group. Conclusion: Considering the good visualization and low complication rate, the direct injection of ICG can be used as an alternative tattooing method.

Retroperitoneal sarcomas: Outcomes of repeated resections.

Purpose: Retroperitoneal sarcomas (RPS) are rare malignant tumors arising from mesenchymal cells. The objective of this study was to review the treatment experiences and to identify prognostic factors for overall survival (OS) after primary resection and subsequent reoperations for recurrences. Methods: The medical records of patients who underwent resection for RPS at our institution between June 2002 and December 2016 were retrospectively reviewed. Univariate and multivariable Cox proportional hazards modeling was used to assess the prognostic factors for OS. Results: A total of 48 patients were enrolled. On multivariable analysis in primary resection group, the FNCLCC (Fédération Nationale des Centres de Lutte Contre le Cancer) grade was a significant prognostic factor for OS (P=0.006). The patients who received chemotherapy after primary resection were significantly associated with poor prognosis (P=0.009). The 5-year OS rate after primary resection (n=48) were 58.1% and the 5-year cumulative reoperation rate after primary resection was 62.5%. After second resection for recurrence after primary resection (n=23), the 5-year OS rate was 64.3%. There was a tendency towards decreased surgery-free survival rate as the number of repeated resections for recurrent RPS increased. In the subset of patients (n=16) who underwent more than 3 repeated resections at our institute, the 5-year OS rate was 75.0%, indicating that repeated resections are not associated with worse outcome. Conclusion: Only low tumor grade was an independent favorable prognostic factor for OS. Although the prognosis for RPS remains poor, repeated resections for recurrence are not associated with poor prognosis. Aggressive surgical strategies for recurred RPS patients are warranted.

Outcomes of surgical treatments for rectovaginal fistula and prognostic factors for successful closure: a single-center tertiary hospital experiences.

PURPOSE: Rectovaginal fistula can result from various causes and diverse surgical procedures have developed as a result. We investigated the outcomes of surgical treatments for rectovaginal fistula according to causes and procedures. METHODS: Between 1998 and 2016, 92 patients underwent 128 operations for rectovaginal fistula. Prospectively collected data were recorded, and a retrospective review was conducted. RESULTS: The median age was 49 years, and low fistula occurred in 58 patients (63.0%). The most common cause was radiation therapy, followed by pelvic operation, birth injury, perineal operation, cancer invasion, and trauma. The most common procedure during the first operation was diverting ostomy alone, followed by transanal rectal advancement flap, sphincteroplasty with perineoplasty, bowel resection, fistulectomy with seton placement, and Martius flap. Thirty-one patients (33.7%) experienced successful closure after the first operation. Repeated operations were performed in 16 patients (17.4%), including gracilis muscle transpositions, stem cell injections, and Martius flaps. The overall success rate was 42.4% (n = 39). Radiation therapy and pelvic operation as cause of fistula were significantly poor prognostic factors (P = 0.010, P = 0.045) and Crohn disease had a tendency for poor prognostic factors (P = 0.058). CONCLUSION: Radiation therapy and pelvic operation for cancer were more common causes than birth injury, and these causes of rectovaginal fistula were the most important prognostic factors. An individualized approach and repeated surgeries with complex or newly developed procedures, even among high-risk causes of fistula, may be necessary to achieve successful closure.

Adjuvant chemotherapy does not provide survival benefits to elderly patients with stage II colon cancer.

To date, the effect of adjuvant chemotherapy after curative resection in patients with stage II colon cancer remains controversial. Still, little is known about the effects of adjuvant chemotherapy in patients with stage II colon cancer who are older than 70 years, as most studies did not focus on this population. This study aimed to investigate the oncologic outcomes of elderly patients with stage II colon cancer who underwent curative resection with or without postoperative adjuvant chemotherapy. We retrospectively reviewed medical records of patients older than 70 years who underwent curative resection of stage II primary colon cancer during 2002-2015. Patients were classified into surgery alone (SA) and adjuvant chemotherapy (AC) groups and propensity score-matched at a 1:1 ratio using a logistic regression. The end points were recurrence-free (RFS), cancer-specific (CSS) and overall survival (OS). Of the 623 patients who met the criteria, 145 were assigned to each arm after propensity score matching. The mean ages of the SA and AC groups were 74.3 and 74.0 years, respectively. A log-rank test revealed no significant inter-group differences in RFS (p = 0.202), CSS (p = 0.486) or OS (p = 0.299). In a Cox regression analysis, adjuvant chemotherapy was not found to be an independent factor affecting RFS (p = 0.206), CSS (p = 0.487) or OS (p = 0.301). Adjuvant chemotherapy does not appear to yield survival benefits in elderly patients with stage II colon cancer.

Safety of temporary ileostomy via specimen extraction site in rectal cancer patients who underwent laparoscopic low anterior resection.

If anastomotic site leakage is expected after laparoscopic low anterior resection (LAR), de-functioning ileostomy is required. However, there is controversy about the consequence of stoma formation via the specimen extraction site (SES). Therefore, we aimed to investigate stoma-related complication according to stoma formation via the SES. We enrolled rectal cancer patients who underwent laparoscopic LAR with temporary ileostomy between January 2013 and December 2017. Patients were divided into two groups: stoma through the SES (SES) and stoma through a new site (NS). The difference in the incidence of stoma-related complications was analysed. In total, 198 patients underwent laparoscopic LAR (SES = 141 patients, NS = 57 patients). The SES group had a shorter operation time (204.7 ± 74.4 min vs 229.5 ± 90.5 min, p = 0.049) and was associated with fewer cases of wound infection (0% vs 7%, p = 0.006) than the NS group. There was no statistically significant difference between the SES group and NS group in all-stoma complications (22.7% vs 12.3%, p = 0.095). The incidence of parastomal hernia also was not significantly different (11.3% vs 5.3%, p = 0.286). Stoma via the SES is feasible after laparoscopic LAR with temporary ileostomy, although stoma-related complication rate was higher, without a significant difference. It can shorten the operation time and reduce wound infection rate.

Oncologic outcomes after adjuvant chemotherapy with capecitabine compared to 5-fluorouracil/leucovorin for geriatric stage II colon cancer: a retrospective cohort study.

PURPOSE: After curative resection of stage II colon cancer, adjuvant chemotherapy with 5-fluorouracil/leucovorin (FL) or capecitabine is selectively recommended. However, there is little evidence of the effect of capecitabine on oncologic outcome in geriatric patients with stage II colon cancer compared to that of FL. The aim of this study was to determine the difference in recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) in patients older than 70 years of age with stage II colon cancer receiving capecitabine and FL. METHODS: Patients over 70 years of age diagnosed with primary pathologic stage II colon cancer at the Seoul National University Hospital from January 2005 to December 2015 were included. A prospectively collected database was analyzed retrospectively. Patients were separated into an FL group and a capecitabine group. The primary outcomes were RFS, CSS, and OS. RESULTS: Of the 154 included patients, 96 patients received FL and 58 patients received capecitabine. There was no difference between the two groups in RFS, CSS, or OS (p = 0.763, p = 0.221, and p = 0.470, respectively) as measured by Kaplan-Meier analysis with log-rank test. Administration of capecitabine as compared to FL was not a factor affecting RFS (hazard ratio [HR] 0.503, 95% confidence interval [CI] 0.145-1.745), CSS (HR 1.519, 95% CI 0.348-6.629), or OS (HR 0.941, 95% CI 0.290-3.053) on multivariable analysis. CONCLUSIONS: Capecitabine is a safe regimen in terms of oncologic outcomes compared with FL in older patients with stage II colon cancer.

Do the Oncological and Surgical Outcomes of Young and Older Women Differ in the Treatment of Colorectal Cancer?

BACKGROUND: The present study aimed to compare the surgical and oncological outcomes between young and older women with colorectal cancer (CRC). MATERIALS AND METHODS: This retrospective study included 1815 women with CRC between 2010 and 2014. Participants were divided into a young group (under the age of 65 years) and an old group (65 years and older). The surgical and oncological outcomes were compared between the two groups using univariate and multivariate analyses. RESULTS: Around 45.1% (N = 819) patients were the older group. The old group had a higher comorbidity rate and a lower proportion of receiving postoperative chemotherapy. The old group also had a significantly higher blood loss (190 ± 611 mL vs. 145 ± 200 mL, p = 0.027) and a higher rate of intraoperative transfusion (5.4% vs. 3.0%, p = 0.011). They were found to develop more complications after surgery (11.7% vs. 7.8%, p = 0.015). The overall survival (OS) of the old group was lower than that of the young group (5-year OS rates: 72.8% vs. 83.8%, p < 0.001; adjusted hazard ratio: 1.86, 95% confidence interval: 1.49-2.33). However, the cancer-specific survival (CSS) was not significantly different between the old and young groups (5-year CSS rates: 84.7% vs. 84.9%, p = 0.076). CONCLUSIONS: Older women with CRC had poorer OS than young women with CRC, but had similar CSS. Therefore, the management of comorbidities along with cancer treatment may be important in older women with CRC.

Prognostic significance of sealed-off perforation in colon cancer: a prospective cohort study.

BACKGROUND: Perforated colon cancer is a rare complication, but has a high risk of recurrence. However, most studies have not distinguished sealed-off perforation from free perforation, and the prognosis is unclear. The aim of this study was to evaluate the oncologic outcome of colon cancer with sealed-off perforation. METHODS: Eighty-six consecutive patients who underwent resection for colon cancer with sealed-off or free perforation were included. We defined sealed-off perforation as a colon perforation with localized abscess identified on operative, computed tomography, or pathologic findings, with no evidence of free perforation, including fecal contamination and dirty fluid collection in the peritoneal cavity. Oncologic outcomes were compared between patients with colon cancer with sealed-off perforation and free perforation using a log-rank test and Cox regression analysis. RESULTS: The sealed-off perforation group included 62 patients, and 24 patients were in the free perforation group. TNM stage and lymphatic, venous, and perineural invasion were similar between the groups. The median follow-up period was 28.9 months (range 0-159). The sealed-off perforation group had better prognosis compared with the free perforation group in terms of progression-free survival (PFS) and overall survival (OS), although there were no statistically significant differences in PFS (5-year PFS 53.7% vs. 40.5%, p = 0.148; 5-year OS 53.6% vs. 22.9%, p = 0.001). However, in multivariable analysis using the Cox progression test, sealed-off perforation did not show a significant effect on cancer progression (p = 0.138) and OS (p = 0.727). CONCLUSIONS: Colon cancer with sealed-off perforation showed no difference in prognosis compared with free perforation.

Significance of lymph node metastasis in the survival of stage IV colorectal cancer by hematogenous metastasis.

PURPOSE: Although lymph node (LN) metastasis is an important prognostic marker of colorectal cancer (CRC), the effect of LN metastasis on the survival of stage IV CRC is debated yet. METHODS: LN status and survivals as well as clinicopathological features of synchronous stage IV CRC patients, operated for 8 years, were analyzed. Patients with hematogenous metastases were included only but those with peritoneal seeding or preoperative adjuvant therapy were not included. RESULTS: Total 850 patients were enrolled and 77 (9.1%) were without LN metastases (N0M1). N0M1 patients were older and have favorable pathological features including lower CEA than patients with LN metastasis (N + M1). The pathologically poor features accumulated with N stage progression within N + M1. N0M1 had better 5-year overall survival (OS) and disease free survival than N + M1. And 5-year OS's within N + M1 group were stratified and different according to N stage progression, although the effect of N stage progression is different according to curative resection or not. When compared with stage III, 5-year OS of N0M1 with curative resection was comparable to that of anyTN2aM0 and was better than anyTN2bM1. CONCLUSION: LN metastasis is a significant prognostic factor in stage IV by hematogenous metastasis, too. N stage progression accumulates pathologically poor prognostic factors. However, the effect on survival of each N stage progression differs depending on curative resection or not of the hematogenous metastases.

The impact of visceral adipose tissue amount on the adequacy of lymph node retrieval in colorectal cancer surgery.

BACKGROUND: Obesity is increasing worldwide, potentially influencing surgical outcomes in colorectal cancer (CRC) patients. We analyzed the effects of obesity indexes on lymph node (LN) retrieval in CRC patients. METHOD: We applied obesity indexes of body mass index (BMI) and visceral (VAT) and subcutaneous (SAT) adipose tissue volumes to stage I-III CRC patients. The primary outcome was the effect of these indexes on the number of retrieved LNs (12 > LNs ≥ 12). RESULTS: Among 519 patients, 35.6% had a BMI ≥ 25 kg/m2 . After adjusting for gender, age, tumor location, resected colon length, and local invasion and LN statuses, patients in the highest VAT quartile showed a 5.848 decrease in the number of retrieved LNs, with an odds ratio of 0.483 (95% confidence interval [CI] 0.260-0.8979) for adequate LN retrieval (≥12), compared with those in the lowest quartile (P < 0.001 for both). Analysis of the model predicting LN retrieval revealed VAT as the only obesity index (area under the curve [AUC] = 0.721) providing significant additional predictive power (P = 0.037) to the model including age, gender, staging, tumor location, and resected colon length (AUC = 0.707). CONCLUSION: Increased VAT may cause inadequate LN retrieval in CRC patients. In viscerally obese patients, VAT volumes should be considered when clinically interpreting LN status.

Predictive Factors for Lymph Node Metastasis and Prognostic Factors for Survival in Rectal Neuroendocrine Tumors.

INTRODUCTION: Neuroendocrine tumors have malignant potential, and lymph node metastasis can occur. This study aimed to identify predictive factors of lymph node metastasis and prognostic factors for survival in rectal neuroendocrine tumors. METHODS: Sixty-four patients underwent endoscopic or surgical treatment for rectal NET. The data on these patients were collected in our database prospectively and reviewed retrospectively. RESULTS: Transanal excision was performed in 28 (43.8%) patients, endoscopic mucosal resection or submucosal dissection was performed in 15 (23.4%) patients, and radical resection was performed in 21 (31.8%) patients. Lymph node and distant metastasis was present in 16 (25.0%) and fir (7.8%) patients. The significant risk factors for lymph node metastasis identified in the multivariable analyses were tumor size (≥ 2 cm, p = 0.003) and tumor grade (G2, p < 0.001; G3, p = 0.008). In patients with a tumor smaller than 2 cm, the risk factors for lymph node metastasis included the tumor grade, mitosis count, and Ki-67 index. The median follow-up period was 30.0 months, and recurrence developed in four (6.8%) patients. The significant prognostic factors for survival included tumor size, T stage, lymph node metastasis, and tumor grade. CONCLUSION: Tumor grade combined with tumor size is an important predictive factor for lymph node metastasis and could serve as a prognostic factor for survival outcomes.

Long-Term Surgical Outcome of Trocar Site Hernia Repair.

Port site hernias are emerging as a problematic complication of laparoscopic surgery. The aim of this study was to elucidate the characteristics of port site hernias and determine the long-term outcomes based on the interval between primary surgery and hernia occurrence. Twenty-four patients were surgically treated for trocar site hernia between 1997 and 2013. The patients were grouped into early-onset group (EOG; less than one month) and late-onset group (LOG; more than one month) based on the interval between laparoscopic surgery and hernia onset. A retrospective analysis was performed. There were seven patients in the EOG and 17 patients in the LOG. The body mass index was significantly higher (P = 0.033) in the LOG. In the EOG, primary closure was performed, and there were no recurrences. In the LOG, mesh reinforcement was applied in 58.8 per cent of patients, and 29.4 per cent of patients had recurrences. This recurrence rate was higher than the recurrence rate after primary repair of incisional hernia after open laparotomy (P = 0.088). In conclusion, In the EOG, small bowel resection was more frequent, but once repaired, there were no recurrences. Although mesh reinforcement was applied in the LOG, the recurrence rate was not less than the EOG.

Erratum: Biofeedback Therapy Before Ileostomy Closure in Patients Undergoing Sphincter-Saving Surgery for Rectal Cancer: A Pilot Study.

[This corrects the article on p. 138 in vol. 31, PMID: 26361615.].

Biofeedback Therapy Before Ileostomy Closure in Patients Undergoing Sphincter-Saving Surgery for Rectal Cancer: A Pilot Study.

PURPOSE: This study prospectively investigated the effects of biofeedback therapy on objective anorectal function and subjective bowel function in patients after sphincter-saving surgery for rectal cancer. METHODS: Sixteen patients who underwent an ileostomy were randomized into two groups, one receiving conservative management with the Kegel maneuver and the other receiving active biofeedback before ileostomy closure. Among them, 12 patients (mean age, 57.5 years; range, 38 to 69 years; 6 patients in each group) completed the study. Conservative management included lifestyle modifications, Kegel exercises, and medication. Patients were evaluated at baseline and at 1, 3, 6, and 12 months after ileostomy closure by using anal manometry, modified Wexner Incontinence Scores (WISs), and fecal incontinence quality of life (FI-QoL) scores. RESULTS: Before the ileostomy closure, the groups did not differ in baseline clinical characteristics or resting manometric parameters. After 12 months of follow-up, the biofeedback group demonstrated a statistically significant improvement in the mean maximum squeezing pressure (from 146.3 to 178.9, P = 0.002). However, no beneficial effect on the WIS was noted for biofeedback compared to conservative management alone. Overall, the FI-QoL scores were increased significantly in both groups after ileostomy closure (P = 0.006), but did not differ significantly between the two groups. CONCLUSION: Although the biofeedback therapy group demonstrated a statistically significant improvement in the maximum squeezing pressure, significant improvements in the WISs and the FI-QoL scores over time were noted in both groups. The study was terminated early because no therapeutic benefit of biofeedback had been demonstrated.

Determination of Spin Inversion Probability, H-Tunneling Correction, and Regioselectivity in the Two-State Reactivity of Nonheme Iron(IV)-Oxo Complexes.

We show by experiments that nonheme Fe(IV)O species react with cyclohexene to yield selective hydrogen atom transfer (HAT) reactions with virtually no C═C epoxidation. Straightforward DFT calculations reveal, however, that C═C epoxidation on the S = 2 state possesses a low-energy barrier and should contribute substantially to the oxidation of cyclohexene by the nonheme Fe(IV)O species. By modeling the selectivity of this two-site reactivity, we show that an interplay of tunneling and spin inversion probability (SIP) reverses the apparent barriers and prefers exclusive S = 1 HAT over mixed HAT and C═C epoxidation on S = 2. The model enables us to derive a SIP value by combining experimental and theoretical results.