Opioid Utilization in Outpatient Anorectal Surgery: An Opportunity for Improvement.

INTRODUCTION: The opioid epidemic has resulted in close examination of postsurgical prescribing patterns. Little is known about postoperative opioid use in outpatient anorectal procedures. This study evaluated patient opioid use and created prescribing recommendations for these procedures. METHODS: One hundred and four patients undergoing outpatient anorectal procedures from January to May 2018 were surveyed on opioid consumption, surgical experience, and pain satisfaction. Patients were grouped into three tiers based on opioid usage. Multivariable models were used to determine factors associated with poor pain control. RESULTS: Patient satisfaction with pain control was 85.6%. Twenty five percent of patients reported leftover medication and 9.6% of patients requested opioid refills. Opioid prescribing recommendations were generated for each tier using 50th percentile with interquartile ranges. On multivariable modeling, the high-tier group was associated with poorer pain control. CONCLUSIONS: We created opioid quantity prescribing guidelines for common outpatient anorectal procedures. A multimodal approach to pain control utilizing nonopioids may reduce healthcare utilization.

Idiopathic Myointimal Hyperplasia of the Mesenteric Veins: A Rare Imitator of Inflammatory Bowel Disease.

Idiopathic myointimal hyperplasia of the mesenteric veins (IMHMV) is a rare cause of chronic colonic ischemia characterized by intimal smooth muscle proliferation and luminal narrowing of the small to medium sized mesenteric veins. It predominantly affects the rectosigmoid colon in otherwise healthy, middle-aged males. Definitive diagnosis and treatment are surgical; however, patients are frequently misdiagnosed, which often results in a protracted clinical course. We describe a case of IMHMV presenting as left hemicolitis in a 53-year-old male, as well as the endoscopic, histopathologic, and radiographic findings that established the diagnosis.

Anal Cancer: Emerging Standards in a Rare Disease.

The social stigma surrounding an anal cancer diagnosis has traditionally prevented open discussions about this disease. However, as recent treatment options and an increasing rate of diagnoses are made worldwide, awareness is growing. In the United States alone, 9,090 individuals were expected to be diagnosed with anal cancer in 2021. The US annual incidence of squamous cell carcinoma of the anus continues to increase by 2.7% yearly, whereas the mortality rate increases by 3.1%. The main risk factor for anal cancer is a human papillomavirus infection; those with chronic immunosuppression are also at risk. Patients with HIV are 19 times more likely to develop anal cancer compared with the general population. In this review, we have provided an overview of the carcinoma of the anal canal, the role of screening, advancements in radiation therapy, and current trials investigating acute and chronic treatment-related toxicities. This article is a comprehensive approach to presenting the existing data in an effort to encourage continuous international interest in anal cancer.

The correlation Between anal pap cytology and histologic outcomes in HIV-Positive males.

BACKGROUND: Anal intraepithelial neoplasia is a precursor to anal carcinoma. The use of anal pap cytology has been accepted as a screening method for anal carcinoma, however sensitivity and specificity vary. MATERIALS AND METHODS: Retrospective cohort study involving 155 HIV-positive males with abnormal anal cytology and surgical resection. RESULTS: 155 patients met inclusion criteria. 31.6% were diagnosed with atypical cytology, 61.9% with low-grade cytology, and 6.4% with high-grade cytology. At surgery, 19.4% were diagnosed with condylomata, 34.8% with anal intraepithelial neoplasia 1, 17.4% with anal intraepithelial neoplasia 2, 27.1% with anal intraepithelial neoplasia 3 and 1.3% with anal carcinoma. There was a positive correlation between high-grade anal cytology and high-grade histology (r = 0.27; p = 0.0008). Comparison of risk factors showed no significant association. CONCLUSION: Anal cytology has a significant correlation with surgical histology. There were still instances of high-grade lesions being found after low-grade cytology. This highlights the necessity of patients with low-grade cytology undergoing anoscopic evaluation.

Is newer always better?: comparing cost and short-term outcomes between laparoscopic and robotic right hemicolectomy.

BACKGROUND: Enthusiasm is high for expansion of robotic assisted surgery into right hemicolectomy. But data on outcomes and cost is lacking. Our objective was to determine the association between surgical approach and cost for minimally invasive right hemicolectomy. We hypothesized that a robot approach would have increased costs (both economic and opportunity) while achieving similar short-term outcomes. METHODS: We performed a retrospective cohort analysis with a simulation of operating room utilization at a quaternary care, academic institution. We enrolled patients undergoing minimally invasive right hemicolectomy from November 2017 to August 2019. Patients were categorized by the intended approach- laparoscopic or robotic. The primary outcome was the technical variable direct cost. Secondary outcomes included total cost, supply cost, operating room utilization, operative time, conversion, length of stay and 30-day post-operative outcomes. RESULTS: 79 patients were included in the study. A robotic approach was used in 22% of the cohort. The groups differed significantly only in etiology of surgery. Robotic surgery was associated with a 1.5 times increase in the technical variable direct cost (p < 0.001), increased supply cost (2.6 times; p < 0.001) and increased total cost (1.3 times; p < 0.001). Significant differences were observed in median room time (Robotic: 285 min vs. Laparoscopic: 170 min; p < 0.001) and procedure time (Robotic: 203 min vs. Laparoscopic: 118 min; p < 0.001). There were no differences observed in post-operative outcomes including length of stay or readmission. In a simulation of OR utilization, 45 laparoscopic right hemicolectomies could be performed in an OR in a month compared to 31 robotic cases. CONCLUSIONS: Robotic right hemicolectomy was associated with increased costs with no improvement in post-operative outcomes. In a simulation of operating room efficiency, a robotic approach was associated with 14 fewer cases per month. Practitioners and administrators should be aware of the increased cost of a robotic approach.

What's the magic number? Impact of time to initiation of treatment for rectal cancer.

BACKGROUND: National guidelines, including the National Accreditation Program for Rectal Cancer, recommend initiation of rectal cancer treatment within 60 days of diagnosis; however, the effect of timely treatment initiation on oncologic outcomes is unclear. The purpose of this study was to evaluate the impact on oncologic outcomes of initiation of rectal cancer treatment within 60 days of diagnosis. METHODS: This was a retrospective review of stage II/III rectal cancer patients performed using the United States Rectal Cancer Consortium, a collaboration of 6 academic medical centers. Patients with clinical stage II/III rectal cancer who underwent radical resection between January 1, 2010 and December 31, 2018 were included. The primary exposure was treatment initiation, defined as either resection or initiation of chemotherapy or chemoradiotherapy, within 60 days of diagnosis. The primary outcome was disease recurrence, and the secondary outcome was all-cause mortality. RESULTS: A total of 1,031 patients meeting inclusion criteria were included in the analysis. Treatment was initiated within 60 days of diagnosis in 830 patients (80.5%) and after 60 days in 201 patients (20.3%). In multivariable logistic regression, older age, non-White race, and residence greater than 100 miles from the treatment center were significantly associated with delay in treatment beyond 60 days. In survival analysis, 167 patients (16.2%) experienced recurrent disease, and 127 patients (12.3%) died of any cause. In an adjusted model accounting for pathologic staging, treatment sequence, distance to care, age, comorbidities, treatment center, and receipt of adjuvant chemotherapy, neither progression-free survival nor all-cause mortality was significantly associated with timely initiation of therapy with hazard ratios of 1.09 (0.70, 1.69) and 1.03 (0.63, 1.66), respectively. CONCLUSION: This study found no difference in oncologic outcomes with initiation of treatment beyond 60 days.

Malignant Large Bowel Obstruction.

Large bowel obstruction is a serious and potentially life-threatening surgical emergency which is associated with high morbidity and mortality rate. The most common etiology is colorectal cancer which accounts for over 60% of all large bowel obstructions. Proper assessment, thoughtful decision-making and prompt treatment is necessary to decrease the high morbidity and mortality which is associated with this entity. Knowledge of the key elements regarding the presentation of a patient with a large bowel obstruction will help the surgeon in formulating an appropriate treatment plan for the patient. Comprehensive knowledge and understanding of the various treatment options available is necessary when caring for these patients. This chapter will review the presentation of patients with malignant large bowel obstruction, discuss the various diagnostic modalities available, as well as discuss treatment options and the various clinical scenarios in which they are most appropriately utilized.

Benchmarking patient satisfaction scores in a colorectal patient population.

BACKGROUND: Healthcare reimbursement is rapidly moving away from a fee-for-service model toward value-based purchasing. An integral component of this new focus on quality is patient-centered outcomes. One metric used to define patient satisfaction is the Press Ganey Patient Satisfaction Survey. Data are lacking to accurately benchmark these scores based on diagnosis. We sought to identify if different colorectal disease processes affected a patient's perception of their healthcare experience. METHODS: Adult colorectal patients seen between July 2015 and September 2016 in a tertiary hospital colorectal clinic were mailed a Press Ganey survey. Patients were stratified based on diagnosis: neoplasia, IBD, anorectal and benign colorectal disease. Survey scores were compared across the groups with adjustment for confounding variables. RESULTS: 312 patients responded and formed the cohort. The mean age was 61 (range 18-93) and 56% were women. The cohort breakdown was 38% neoplasia, 32% anorectal, 21% benign, and 9% IBD. In a multivariable model, there was a difference in PG scores by diagnosis; patients with neoplasia had higher Overall scores (ß 10.2; Std Error 4.0; p = 0.01), Care Provider scores (ß 8.5; Std Error 4.2; p = 0.04), Nurse Assistant scores (ß 15.0; Std Error 5.7; p = 0.01), and Personal Issues scores (ß 11.8; Std Error 5/0; p = 0.01). CONCLUSION: Press Ganey scores were found to vary significantly. Patients with a neoplasia diagnosis reported higher overall satisfaction, Care Provider, Nurse Assistant, and Personal Issues scores. Adjustment for disease condition is important when assessing patient satisfaction as an indicator of quality and as a metric for reimbursement. This study adds to increasing evidence about bias in these scores.

Comparing pathologic outcomes for robotic versus laparoscopic Surgery in rectal cancer resection: a propensity adjusted analysis of 7616 patients.

BACKGROUND: Margin negative resection of rectal cancer with minimally invasive techniques remains technically challenging. Robotic surgery has potential advantages over traditional laparoscopy. We hypothesize that the difference in the rate of negative margin status will be < 6% between laparoscopic and robotic approach. METHODS: The National Cancer Database (2010-2014) was queried for adults with locally advanced rectal cancer who underwent neoadjuvant chemoradiation and curative resection to conduct an observational retrospective cohort study of a prospectively maintained database. Patients were grouped by either robotic (ROB) or laparoscopic (LAP) approach in an intent-to-treat analysis. Primary outcome was negative margin status, defined as a composite of circumferential resection margin and distal margin. Secondary outcomes included length of stay (LOS), readmission, 90-day mortality, and overall survival. RESULTS: 7616 patients with locally advanced rectal cancer who underwent minimally invasive resection were identified. 2472 (32%) underwent attempted robotic approach. The overall conversion rate was 13% and was increased in the laparoscopic group [LAP: 15% vs. ROB: 8%; OR 0.47; 95% CI (0.39, 0.57)]. Differences in margin negative resection rate were within the prespecified range of practical equivalence (LAP: 93% vs.: ROB 94%; 95% CI (0.69, 1.06); [Formula: see text] = 1). For secondary outcomes, there was no difference in 30-day readmission [LAP: 9% vs.: ROB 8%; 95% CI (0.84, 1.24)] and 90-day mortality [LAP: 1% vs.: ROB 1%; 95% CI (0.38, 1.24)]. While the median LOS was 5 days in both groups, the mean LOS was 0.6 (95% CI: 0.24, 0.89) days shorter in the robotic group. CONCLUSION: This robust analysis supports either robotic or laparoscopic approach for resection of locally advanced rectal cancer from a margin perspective. Both have similar readmission and 5-year overall survival rates. Patients undergoing robotic surgery have a 0.6-day decrease in LOS and decreased conversion rate.

Surgical management of primary colonic lymphoma: Big data for a rare problem.

BACKGROUND AND OBJECTIVES: Primary colonic lymphoma (PCL) is rare, heterogeneous, and presents a therapeutic challenge for surgeons. Optimal treatment strategies are difficult to standardize, leading to variation in therapy. Our objective was to describe the patient characteristics, short-term outcomes, and five-year survival of patients undergoing nonpalliative surgery for PCL. METHODS: We performed a retrospective cohort analysis in the National Cancer Database. Included patients underwent surgery for PCL between 2004 to 2014. Patients with metastases and palliative operations were excluded. Univariate predictors of overall survival were analyzed using multivariable Cox proportional hazard analysis. RESULTS: We identified 2153 patients. Median patient age was 68. Diffuse large B-cell lymphoma accounted for 57% of tumors. 30- and 90-Day mortality were high (5.6% and 11.1%, respectively). Thirty-nine percent of patients received adjuvant chemotherapy. For patients surviving 90 days, 5-year survival was 71.8%. Chemotherapy improved survival (surgery+chemo, 75.4% vs surgery, 68.6%; P = .01). Adjuvant chemotherapy was associated with overall survival after controlling for age, comorbidity, and lymphoma subtype (HR 1.27; 95% CI, 1.07-1.51; P = .01). CONCLUSIONS: Patients undergoing surgery for PCL have high rates of margin positivity and high short-term mortality. Chemotherapy improves survival, but <50% receive it. These data suggest the opportunity for improvement of care in patients with PCL.

Assessing Hereditary Colorectal Cancer Referral Patterns to a Tertiary Care Center: A Novel Approach Using Geographic Information System Mapping.

BACKGROUND: Patients and their family members with hereditary colorectal cancer require longitudinal follow-up that is best achieved through a dedicated program with a registry. However, referrals for these conditions remain poor. Geographic information systems technology is a novel method to evaluate geographic variation in multiple realms but is being used more in health care. OBJECTIVE: The purpose of this study was to evaluate referral patterns with geographic information systems technology to better target efforts for improving overall referrals. We hypothesized that marked variation would exist as to the geospatial locations of referrals and that gastroenterologists would be the dominant referral source. DESIGN: This was a retrospective cross-sectional study. SETTINGS: The study was conducted at Vanderbilt University Medical Center. PATIENTS: The hereditary colorectal cancer registry was queried from June 2007 to August 2016 for demographics, distance to center, genetic mutations, and the specialty of the referring providers. Geospatial data on both patient and referring specialist were collected. MAIN OUTCOME MEASURES: We analyzed patient and referral data with geographic information systems technology to look for gaps and patterns. RESULTS: A total of 676 patients were entered into the registry during this period. Fifty-six percent were women, and the median age was 50 years (interquartile range, 42-60 y). The median distance from the center was 60 miles (interquartile range, 22-120 miles), and 31% carried an identified germline mutation. Gastroenterology represented the overall largest source of referrals and, when broken down by syndrome, they represented the top referral specialty for familial adenomatous polyposis. Surgeons were the largest referral source for Lynch syndrome. LIMITATIONS: The study was limited by covariates in the database. CONCLUSIONS: Our hereditary colorectal cancer registry serves a large geographic area, with the largest group of referrals coming from gastroenterologists. Performing this analysis with geographic information systems technology mapping allowed us to identify clustering of patients and providers throughout the region as well as gaps. This information will help to target outreach and distribution of educational materials for providers and their patients to increase registry enrollment. See Video Abstract at http://links.lww.com/DCR/A950.

Neoadjuvant radiation for clinical T4 colon cancer: A potential improvement to overall survival.

BACKGROUND: Resection of T4 colon cancer remains challenging compared to lower T stages. Data on the effect of neoadjuvant radiation to improve resectability and survival are lacking. The purpose of this study is to describe the use and outcomes of neoadjuvant radiation therapy in clinical T4 colon cancer. METHODS: Adults with clinical evidence of T4 locally advanced colon cancer were included from the National Cancer Database (2004-2014). Bivariate and multivariable analyses were used to examine the association between neoadjuvant radiation therapy and R0 resection rate, multivisceral resection, and overall survival. RESULTS: Fifteen thousand two hundred and seven patients with clinical T4 disease who underwent resection were identified over the study period. One hundred ninety-five (1.3%) underwent neoadjuvant radiation therapy. Factors associated with the use of neoadjuvant radiation therapy included younger age, male sex, private insurance, lower Charlson Comorbidity Index score, and treatment at an academic research program. Neoadjuvant radiation therapy was associated with superior R0 resection rates (87.2% neoadjuvant radiation therapy vs 79.8% no neoadjuvant radiation therapy; P = .009). Five-year overall survival was increased in the neoadjuvant radiation therapy group (62.0% neoadjuvant radiation therapy vs 45.7% no neoadjuvant radiation therapy; P < .001). The benefit of neoadjuvant radiation therapy persisted in a Cox proportional hazards multivariable model containing a number of confounding variables, including comorbidity and postoperative chemotherapy (odds ratio 1.37; 95% confidence interval 1.05-1.77; P = .01). In a subgroup analysis of T4b patients, there was an even greater size effect in adjusted overall survival (odds ratio 1.71; 95% confidence interval 1.07-2.72; P = .02). CONCLUSION: Although radiation is rarely used in locally advanced colon cancer, this National Cancer Database analysis suggests that the use of neoadjuvant radiation for clinical T4 disease may be associated with superior R0 resection rates and improved overall survival. Patients with clinical T4b disease may benefit the most from treatment. Neoadjuvant radiation therapy should be considered on a case-by-case basis in locally advanced colon cancer.

An enhanced recovery program in colorectal surgery is associated with decreased organ level rates of complications: a difference-in-differences analysis.

BACKGROUND: Perioperative care has lacked coordination and standardization. Enhanced recovery programs (ERPs) have been shown to decrease aggregate complications across surgical specialties. We hypothesize that the sustained implementation of an ERP will be associated with a decrease in a broad range of complications at the organ system level. STUDY DESIGN: Adult patients undergoing elective colorectal procedures between 1/2011 and 10/2016 were included. Patients were stratified based on exposure to a sustained ERP (7/2014-10/2016) after an 18-month wash-in period in a pre-post analysis. The primary outcome was 30-day complication rate by organ category as collected by National Surgical Quality Improvement Program (NSQIP) abstractors. Demographic and other patient level data were collected. Complication rates were compared using multivariable regression employing a differences-in-differences (DiD) approach using the national NSQIP PUF file to account for secular trends. RESULTS: A total of 1182 patients were included in this study, with 47% treated in an ERP. The two groups were similar in age, gender, race, BMI, comorbidity index, and procedure type. In a multivariable DiD analysis, significant reductions were seen in surgical site infection (OR 0.30; 95% CI 0.20-0.43), postoperative pulmonary complications (OR 0.46; 95% CI 0.24-0.90), transfusion (OR 0.27; 95% CI 0.15-0.51), urinary tract infections (OR 0.34; 95% CI 0.18-0.66), sepsis (OR 0.35; 95% CI 0.20-0.61), and cardiac complications (OR 0.10; 95% CI 0.01-0.84). A reduction in return to the operating room and 30-day readmission was also observed. Median length of stay (LOS) decreased from 5.2 to 3.5 days (p < 0.001). No significant changes occurred for acute kidney injury and hematologic complications. CONCLUSION: An ERP was associated with reduced complication rates across a wide range of organ categories and > 1.5-day reduction in LOS in a colorectal surgery population.

Ketorolac Use and Anastomotic Leak in Elective Colorectal Surgery: A Detailed Analysis.

BACKGROUND: Recent population-level analyses have linked ketorolac use to adverse outcomes. However, its use is also associated with decreased opioids and faster return of bowel function. OBJECTIVE: This study aims to assess the association between ketorolac and anastomotic leak. We hypothesize that receiving at least 1 dose of ketorolac will not be associated with anastomotic leak in elective colorectal surgery. DESIGN: This is a retrospective, observational cohort study of a prospectively collected data base. Anastomotic leak rates and other patient outcomes were adjusted for patient-level factors and then compared via a multivariable logistic regression. A secondary analysis assessed a dose-response association with anastomotic leak. SETTING: This study was conducted at a tertiary care colorectal surgery service. PATIENTS: Consecutive patients undergoing elective colorectal surgery with a nondiverted anastomosis were identified from 2012 to 2016. INTERVENTION: Exposure was defined as any administration of ketorolac during the perioperative time period. MAIN OUTCOME MEASURES: The primary outcome measured was anastomotic leak. RESULTS: A total of 877 patients met inclusion criteria. Of these, 479 (54.6%) were women, and the median age was 55 years. Overall, 566 (64.5%) patients were exposed to ketorolac. In the cohort, 27 (3.1%) patients experienced an anastomotic leak. In an unadjusted analysis, there was no association between ketorolac exposure and anastomotic leak (ketorolac: 3.1% vs no ketorolac: 3.3%; p = 0.84). This persisted in a multivariable model (OR, 0.98; 95% CI, 0.38-2.57; p = 0.98). Neither AKI (OR, 3.24; 95% CI, 0.51-20.6; p = 0.21), return to the operating room (OR, 1.07; 95% CI, 0.40-2.85; p = 0.88), nor readmission (OR, 1.03; 95% CI, 0.59-1.80; p = 0.93) was associated with ketorolac use. In a secondary analysis of patients receiving ketorolac, there was no association between total ketorolac dosing and anastomotic leak (OR, 0.99; 95% CI, 0.99-1.00; p = 0.20). LIMITATIONS: This study was a retrospective review, and there was a low incidence of anastomotic leak. CONCLUSION: Ketorolac exposure was associated with neither anastomotic leak nor other important postoperative outcomes. See Video Abstract at http://links.lww.com/DCR/A784.

Resection for anal melanoma: Is there an optimal approach?

BACKGROUND: Anal melanoma is a lethal disease, but its rarity makes understanding the behavior and effects of intervention challenging. Local resection and abdominal perineal resection are the proposed treatments for nonmetastatic disease. We hypothesize that there is no difference in overall survival between surgical therapies. METHODS: The National Cancer Database (2004-2014) was queried for adults with a diagnosis of anal melanoma who underwent curative resection. Patients with metastatic disease were excluded. Patients were divided into 2 groups based on surgical approach (local resection versus abdominal perineal resection). Unadjusted and adjusted analyses were used to examine the association between surgical approach and R0 resection rate, short-term survival, and overall survival. RESULTS: A total of 570 patients with anal melanoma who underwent resection were identified. The median age was 68 and 59% of patients were female. A total of 383 (67%) underwent local resection. Abdominal perineal resection was associated with higher rates of R0 resection rates (abdominal perineal resection 91% versus local resection 73%; P < .001). Overall 5-year survival for the entire cohort was 20%. There was no significant difference in 5-year overall survival (abdominal perineal resection 21% vs local resection 17%; P = .31). This persisted in a Cox proportional hazard multivariable model (odds ratio 0.84; 95% confidence interval 0.66-1.06; P = .15). Additionally, there was no improvement in overall survival for patients who underwent R0 resection (odds ratio 1.18; 95% confidence interval 0.90-1.56; P = .22). CONCLUSION: Anal melanoma has a very poor prognosis, with only 1 of 5 patients alive at 5 years. Although local resection was associated with lower rates of R0 resection, there was no discernable difference in overall survival in both unadjusted and adjusted analysis.

Management of colonoscopic perforations: A systematic review.

BACKGROUND: Perforation during colonoscopy is a rare but well recognized complication with significant morbidity and mortality. We aim to systematically review the currently available literature concerning care and outcomes of colonic perforation. An algorithm is created to guide the practitioner in management of this challenging clinical scenario. DATA SOURCES: A systematic review of the literature based on PRISMA-P guidelines was performed. We evaluate 31 articles focusing on findings over the past 10 years. CONCLUSION: Colonoscopic perforation is a rare event and published management techniques are marked by their heterogeneity. Reliable conclusions are limited by the nature of the data available - mainly single institution, retrospective studies. Consensus conclusions include a higher rate of perforation from therapeutic colonoscopy when compared to diagnostic colonoscopy and the sigmoid as the most common site of perforation. Mortality appears driven by pre-existing conditions. Treatment must be tailored according to the patient's comorbidities and clinical status as well as the specific conditions during the colonoscopy that led to the perforation.

Barriers to laparoscopic colon resection for cancer: a national analysis.

BACKGROUND: Level one evidence has shown that minimally invasive surgery (MIS) for colon cancer improves short-term outcomes with equivalent long-term oncologic results when compared to open surgery. However, the adoption of MIS for patients with colon cancer has not been universal. The goal of this study is to identify barriers to the use of MIS surgery in colon cancer resection across the United States. METHODS: The National Cancer Database was queried for all cases of colonic adenocarcinoma resection from 2010 to 2012. Patients undergoing an MIS approach were compared with those undergoing open surgery (OS). MIS was defined as either robotic or laparoscopic surgery. Patients with metastatic disease, surgery for palliation, or tumors >8 cm were excluded. Multivariable modeling was used to identify variables associated with the use of open surgery. RESULTS: After applying exclusion criteria, 124,205 cases were identified. An MIS approach was used in only 54,621 (44%) patients. In a multivariable model adjusting for stage and tumor size, a number of important factors were associated with decreased odds of a MIS approach including black race (OR .91; p < .0001), lack of insurance (OR .51; p < .0001), lower education (OR .88; p < .0001), lower income (OR .83; p < .0001), treatment at a community program (OR .86; p < .0001), and treatment at a low-volume center (OR .79; p < .0001). Utilization of MIS increased over the study period (2010: 38.7%, 2011: 44.0%, 2012: 49.1%; p < .0001). CONCLUSIONS: MIS approach is utilized in less than half of all colon resections in this national database, which accounts for over 70% of all diagnosed cancers in the US. Significant variability exists among age, race, insurance status, socioeconomic status, region, and facility type. In light of the recognized benefits of the MIS approach, local and national policy should focus on narrowing these disparities and continuing the upward trend of MIS utilization.

Correction: Human alpha defensin 5 is a candidate biomarker to delineate inflammatory bowel disease.

[This corrects the article DOI: 10.1371/journal.pone.0179710.].

Nodal Disease in Rectal Cancer Patients With Complete Tumor Response After Neoadjuvant Chemoradiation: Danger Below Calm Waters.

BACKGROUND: A subset of patients with rectal cancer who undergo neoadjuvant chemoradiation therapy will develop a complete pathologic tumor response. Complete nodal response is not universal in these patients and is difficult to assess clinically. Quantifying the risk of nodal disease would allow for targeted therapy with either radical resection or "watchful waiting." OBJECTIVE: This study aimed to identify risk factors for residual nodal disease in ypT0 rectal adenocarcinoma. DESIGN: This is a retrospective case control study. SETTINGS: The National Cancer Database 2006 to 2014 was used to identify patients for this study. PATIENTS: Patients with stage II/III rectal adenocarcinoma who completed chemoradiation therapy followed by resection and who had ypT0 tumors were included. Patients with metastatic disease and <2 lymph nodes evaluated were excluded. Patients were divided into 2 groups: node positive and node negative. MAIN OUTCOME MEASURES: The main outcome was nodal disease. The secondary outcome was overall survival. RESULTS: A total of 42,257 patients with stage II/III rectal cancer underwent chemoradiation therapy and radical resection; 4170 (9.9%) patients had ypT0 tumors and 395 (9.5%) were node positive. Of patients with clinically node-negative disease (ie, pretreatment imaging), 6.2% were node positive after chemoradiation therapy and resection. In multivariable analysis, factors predictive of nodal disease included increasing (pretreatment) clinical N-stage, high tumor grade (3/4), perineural invasion, and lymphovascular invasion. Higher clinical T-stage was inversely associated with residual nodal disease. Overall 5-year survival was significantly different between patients with ypN0, ypN1, and ypN2 disease (87.4%, 82.2%, and 62.5%, p = 0.002). LIMITATIONS: This study was limited by the lack of clinical detail in the database and the inability to assess recurrence. CONCLUSIONS: Ten percent of patients with ypT0 tumors had positive nodes after chemoradiation therapy and resection. Factors associated with residual nodal disease included clinical nodal disease at diagnosis and poor histologic features. Patients with any of these features should consider radical resection regardless of tumor response. Others could be suitable for "watchful waiting" strategies. See Video Abstract at http://links.lww.com/DCR/A458.