Genome-Wide Association Study Identifies Genes for Hair Growth and Patterning are Associated With Pilonidal Disease.

BACKGROUND: Pilonidal sinus disease is a highly morbid condition characterized by the formation of chronic sinus tracts throughout the sacrococcygeal region. Despite its commonality and strong association with family history, there is no prior investigation of genetic risk factors for pilonidal sinus disease. OBJECTIVE: To identify genetic risk factors for pilonidal sinus disease. DESIGN: Genome-wide association study. SETTINGS: The United Kingdom Biobank, FinnGen Biobank, and PennMedicine Biobank. PATIENTS: There were 772,072 participants. MAIN OUTCOME MEASURE: Genome-wide significant variants (p < 5x10 -8) were mapped to genes using physical distance and gene expression in skin. Genetic correlation between pilonidal sinus disease and morphometric, androgen-driven, and hair phenotypes was estimated with LD score regression. Finally, a genome-first approach to rare, predicted deleterious variants in hair shaft genes TCHH, PADI3, and TGM3 was conducted for association with pilonidal sinus disease via PennMedicine Biobank. RESULTS: Genome-wide association study comprised of 2,835 individuals with pilonidal sinus disease identified 5 genome-wide significant loci, prioritizing HDAC9, TBX15, WARS2, RP11-293M10.1, PRKAR1B, TWIST1, GPATCH2L, NEK9, and EIF2B2, as putative causal genes; several of these genes have known roles in balding and hair patterning. There was significant correlation between the genetic background of pilonidal sinus disease and that of the androgen-driven hair traits male pattern baldness and young age at first facial hair. In a candidate analysis of genes associated with syndromic hair disorders, rare coding variants in TCHH, a monogenic cause of uncombable hair syndrome, were associated with increased prevalence of pilonidal sinus disease (OR 4.81 [5% CI, 2.06-11.2]). LIMITATIONS: This study is limited to European ancestry. However, because there is a higher incidence of pilonidal sinus disease in men of European ancestry, this analysis is focused on the at-risk population. CONCLUSION: Genetic analysis of pilonidal sinus disease identified shared genetic architecture with hair biology and androgen-driven traits. As the first study investigating the genetic basis of pilonidal sinus disease, this provides biological insight into the long-appreciated connection between the disease state, male gender, and hair. See Video abstract.

Polygenic Risk Prediction in Diverticulitis.

OBJECTIVE: To derive and validate a polygenic risk score (PRS) to predict the occurrence and severity of diverticulitis and to understand the potential for incorporation of a PRS in current decision-making. BACKGROUND: PRS quantifies genetic variation into a continuous measure of risk. There is a need for improved risk stratification to guide surgical decision-making that could be fulfilled by PRS. It is unknown how surgeons might integrate PRS in decision-making. METHODS: We derived a PRS with 44 single-nucleotide polymorphisms associated with diverticular disease in the UK Biobank and validated this score in the Michigan Genomics Initiative (MGI). We performed a discrete choice experiment of practicing colorectal surgeons. Surgeons rated the influence of clinical factors and a hypothetical polygenic risk prediction tool. RESULTS: Among 2812 MGI participants with diverticular disease, 1964 were asymptomatic, 574 had mild disease, and 274 had severe disease. PRS was associated with occurrence and severity. Patients in the highest PRS decile were more likely to have diverticulitis [odds ratio (OR)=1.84; 95% confidence interval (CI), 1.42-2.38)] and more likely to have severe diverticulitis (OR=1.61; 95% CI, 1.04-2.51) than the bottom 50%. Among 213 surveyed surgeons, extreme disease-specific factors had the largest utility (3 episodes in the last year, +74.4; percutaneous drain, + 69.4). Factors with strongest influence against surgery included 1 lifetime episode (-63.3), outpatient management (-54.9), and patient preference (-39.6). PRS was predicted to have high utility (+71). CONCLUSIONS: A PRS derived from a large national biobank was externally validated, and found to be associated with the incidence and severity of diverticulitis. Surgeons have clear guidance at clinical extremes, but demonstrate equipoise in intermediate scenarios. Surgeons are receptive to PRS, which may be most useful in marginal clinical situations. Given the current lack of accurate prognostication in recurrent diverticulitis, PRS may provide a novel approach for improving patient counseling and decision-making.

Is There a Role for Adjuvant Chemotherapy in Pathologic Node-Negative Locally Advanced Rectal Cancer After Neoadjuvant Chemoradiation Therapy?

BACKGROUND: Neoadjuvant chemoradiation therapy (NCRT, 5-fluorouracil and radiation) followed by resection and adjuvant chemotherapy (AC) is one of the standard treatment paradigms for locally advanced rectal adenocarcinoma. However, the utility of AC in patients with pathologic lymph node (pLN)-negative disease is unclear. Our aim is to assess the value of AC stratified by pLN status. METHODS: The US Rectal Cancer Consortium database (2007-2017) was retrospectively reviewed for patients with clinical stage II and III rectal adenocarcinoma who received neoadjuvant chemoradiation (NACR) and curative-intent resection. Those who received neoadjuvant systemic chemotherapy or underwent local resection were excluded. Patients were categorized by pLN status. Primary outcome was overall survival (OS). RESULTS: Of 213 patients, 70% had pLN-negative disease and 30% pLN-positive disease. Median age was 57 years, 65% were male, and median follow-up was 31 months. Among patients with pLN-negative disease, 74% received AC. Receipt of AC was not associated with improved 5-year OS (82% versus 74%, respectively; p = 0.16). This finding persisted on multivariable analysis. Of patients with pLN-positive disease, 83% received AC. Patients with pLN-positive disease demonstrated improved 5-year OS with receipt of AC (72% compared with 0% with no adjuvant chemotherapy, p = 0.04). CONCLUSION: After receiving neoadjuvant chemoradiation, adjuvant chemotherapy for patients with pLN-negative disease does not appear to be associated with improved survival. Further validation and prospective studies are needed to evaluate the utility of adjuvant chemotherapy in this setting.

Parastomal Hernia Rates and Exercise After Ostomy Surgery.

BACKGROUND: Parastomal hernias are common and negatively affect patient's lives. We hypothesized that physical activity (or lack thereof) might be associated with the presence of parastomal hernia. If so, this might be an actionable target for prevention. OBJECTIVE: The objective was to determine rates of and risk factors for parastomal hernias in patients with a permanent ostomy. DESIGN: This was a retrospective cohort and survey study. Postal survey included questions about parastomal hernia, symptoms, lifestyle, and validated instruments to measure stoma quality of life and physical activity. Medical record abstraction was conducted for clinical comorbidities. SETTINGS: This study was conducted in a single large academic medical center. PATIENTS: Patients who underwent operations that included a permanent urostomy, colostomy, and/or ileostomy between 2014 and 2018 were included. MAIN OUTCOME MEASURES: Parastomal hernia (self-reported) and physical activity, measured in total metabolic equivalent-minutes/week, were our main outcome measures. RESULTS: A total of 443 of 724 patients responded (response rate, 61.2%). Two hundred twelve patients (47.9%) had urostomies, 160 (36.1%) had colostomies, and 99 (22.3%) had ileostomies. One hundred twenty-eight patients (29.7%) had a parastomal hernia, with rates of 27.1% for urostomy, 40.0% for colostomy, and 23.7% for ileostomy. There was a statistically significant association between less exercise and higher incidence of parastomal hernia (median, 579 metabolic equivalent-minutes/week for those with parastomal hernias vs 1689 metabolic equivalent-minutes/week for those without; p = 0.001). LIMITATIONS: The association between physical activity and parastomal hernia may be confounded by obesity or the possibility that patients with parastomal hernia may be limited physically by their hernia. CONCLUSIONS: Parastomal hernia rates remain high in modern surgical practice. This study shows an association between patients' physical activity and the presence of a parastomal hernia, with a higher rate among patients who exercise less. See Video Abstract at http://links.lww.com/DCR/B910 . TASAS DE HERNIA PARAESTOMAL Y EJERCICIO DESPUS DE LA CIRUGA DE OSTOMA: ANTECEDENTES:Las hernias paraostomales son complicaciones comunes después de la cirugía de ostomía y afectan la calidad de vida de los pacientes. Nuestra hipótesis es que la actividad física de los pacientes (o la falta de ella) podría estar asociada con la presencia de hernia paraostomal. Si es así, este podría ser un objetivo utilizable para la prevención.OBJETIVO:Determinar las tasas y los factores de riesgo de las hernias paraostomales en pacientes que se sometieron a una cirugía que resultó en una ostomía permanente.DISEÑO:Estudio retrospectivo de cohorte y encuesta. La encuesta postal incluyó preguntas sobre hernia paraostomal, síntomas, estilo de vida e instrumentos validados para medir la calidad de vida del paciente ostomizado y la actividad física. Se realizó la confección de gráficos para las comorbilidades clínicas.ESCENARIO:Centro médico académico de gran tamañoPACIENTES:Pacientes que se sometieron a operaciones que incluyeron una urostomía permanente, colostomía y/o ileostomía entre 2014 y 2018.PRINCIPALES MEDIDAS DE RESULTADO:La hernia paraostomal (autoinformada) y la actividad física, medidas en equivalente metabólico de actividad total-minutos/semana, fueron nuestras principales medidas de resultado. También se evaluó la calidad de vida.RESULTADOS:Un total de 443 de 724 pacientes respondieron a la encuesta (tasa de respuesta 61,2%). 212 pacientes (47,9%) tenían urostomías, 160 (36,1%) colostomías y 99 (22,3%) ileostomías. 128 pacientes (29,7%) tenían hernia paraostomal, con tasas de 27,1% para urostomía, 40,0% para colostomía y 23,7% para ileostomía. Hubo una asociación estadísticamente significativa entre menos ejercicio y una mayor incidencia de hernia paraostomal (mediana: 579 equivalentes metabólicos - minutos/semana para aquellos con hernias paraostomales versus 1689 para aquellos sin hernias; p = 0,001).LIMITACIONES:La asociación entre la actividad física y la hernia paraostomal puede confundirse con la obesidad o con el hecho de que los pacientes con hernia paraostomal pueden tener menos actividad física debido a su hernia.CONCLUSIONES:Las tasas de hernia paraostomal siguen siendo altas en la práctica quirúrgica moderna y las hernias se asocian con una peor calidad de vida. Este estudio muestra una asociación entre la actividad física de los pacientes y la presencia de una hernia paraostomal, con una tasa más alta entre los pacientes que hacen menos ejercicio. Consulte Video Resumen en http://links.lww.com/DCR/B910 . (Traducción-Dr. Felipe Bellolio ).

Management and Outcomes of Pathologic Upstaging of Clinical Stage I Rectal Cancers: An Exploratory Analysis.

BACKGROUND: Preoperative staging of clinical stage I rectal cancer can fail to diagnose T3 or nodal disease. Adjuvant treatment of these upstaged patients remains controversial. OBJECTIVE: The objective was to identify predictors of clinical stage I rectal cancer upstaging and quantify rates of local and systemic recurrence. DESIGN: This was a retrospective cohort study. SETTINGS: The study was conducted using data from the United States Rectal Cancer Consortium, a registry of 1881 rectal cancer resections performed at 6 academic medical centers. PATIENTS: There were a total of 94 clinical stage I rectal cancer patients who underwent proctectomy without preoperative therapy. MAIN OUTCOME MEASURES: The primary measures were incidence of pathologic upstaging, recurrence (local and systemic), and overall survival. RESULTS: Among 94 clinical stage I patients who underwent proctectomy without preoperative therapy, 23 (24.5%) were upstaged by surgical pathology. There were 6 pT3N0 patients, 8 pT1-2N+ patients, and 9 pT3N+ patients. There were no significant differences in demographic or clinical characteristics between upstaged and nonupstaged patients. Of the 6 patients who were upstaged to T3N0 disease, none received adjuvant therapy and none developed recurrence. Of the 17 patients who were upstaged to N+ disease, 14 (82%) received adjuvant chemotherapy and 6 (35%) received adjuvant chemoradiation. None developed a local recurrence, but 4 (24%) developed systemic recurrence, and 2 (12%) died of disease over a mean of 36 months of follow-up. Among the 9 pT3N+ patients, the systemic recurrence rate was 33%, despite 8 of 9 patients receiving adjuvant fluorouracil, leucovorin, and oxaliplatin. LIMITATIONS: Small sample size hinders the ability to draw significant conclusions. CONCLUSIONS: One in 4 patients with stage I rectal cancer had unrecognized T3 or nodal disease found on operative pathology. Occult nodal disease was associated with worse outcomes, despite receiving adjuvant therapy. Systemic recurrence was more common than local recurrence. See Video Abstract at http://links.lww.com/DCR/B885 . MANEJO Y RESULTADOS DEL AUMENTO DEL ESTADIO PATOLGICO DE LOS CNCERES DE RECTO EN ESTADIO CLNICO I UN ANLISIS EXPLORATORIO: ANTECEDENTES:El estadiaje pre-operatorio del cáncer de recto en fase clínica I puede ser erróneo en el diagnóstico T3 o en la diseminación ganglionar. El tratamiento adyuvante de estos pacientes sobre-estadificados ​​sigue siendo controvertido.OBJETIVO:El identificar los factores predictivos en fase clínica I del cáncer de recto y cuantificar las tasas de recurrencia local y sistémica.DISEÑO:Estudio de cohortes retrospectivo.AJUSTE:El estudio se realizó utilizando los datos del Consorcio del Cáncer de Recto de los Estados Unidos, con un registro de 1.881 resecciones oncológicas rectales realizadas en seis centros médicos académicos.PACIENTES:Un total de 94 pacientes con cáncer de recto en fase clínica I fueron sometidos a proctectomía sin terapia preoperatoria.PRINCIPALES MEDIDAS DE RESULTADO:Las medidas primarias fueron la incidencia del sobre-estadiaje histopatológico, la recurrencia (local y sistémica) y la sobrevida general.RESULTADOS:De 94 pacientes en fase clínica I que se sometieron a una proctectomía sin terapia preoperatoria, 23 (24,5%) fueron sobre-estadiados ​​por la histopatología quirúrgica. Hubieron 6 pacientes pT3N0, 8 pT1-2N + y 9 pT3N +. No hubo diferencias significativas en las características demográficas o clínicas entre los pacientes sobre-estadiados ​​y los no sobre-estadiados. De los 6 pacientes que fueron sobre-estadiados en la enfermedad T3N0, ninguno de ellos recibió terapia adyuvante y ninguno recidivó. De los 17 pacientes que fueron sobre-estadiados a la enfermedad N +, 14 (82%) recibieron quimioterapia adyuvante y 6 (35%) recibieron quimio-radioterapia adyuvante. Ninguno desarrolló recidiva local, pero 4 (24%) desarrollaron recidiva sistémica y 2 (12%) murieron a causa de la enfermedad durante el seguimiento medio de 36 meses. Entre los 9 pacientes con pT3N +, la tasa de recidiva sistémica fue del 33%, a pesar de que 8 de 9 pacientes recibieron fluorouracilo, leucovorina y oxaliplatino como quimio-adyuvantes.LIMITACIONES:El tamaño pequeño de la muestra dificulta la capacidad de obtener conclusiones significativas.CONCLUSIONES:Uno de cada cuatro pacientes con cáncer de recto en estadío I presentaba enfermedad ganglionar o T3 no descrita en la histopatología operatoria. La enfermedad ganglionar oculta se asoció con peores resultados, a pesar de recibir terapia adyuvante. La recidiva sistémica fue más común que la recidiva local. Consulte Video Resumen en http://links.lww.com/DCR/B885 . (Traducción-Dr. Xavier Delgadillo ).

Outcomes in Enteral Access Based on Specialty and Approach: A Single-Center Three-Year Experience.

INTRODUCTION: Interventional radiologic, endoscopic, and surgical approaches are commonly utilized to establish durable enteral access in adult patients. The purpose of this study is to examine differences in nutritional outcomes in a large cohort of patients undergoing enteral access creation. METHODS: Adult patients who underwent enteral access procedures by interventional radiologists, gastroenterologists, and surgeons between 2018 and 2020 at a single institution were reviewed. Included access types were percutaneous endoscopic gastrostomy (PEG), open or laparoscopic gastrostomy, laparoscopic jejunostomy, and percutaneous gastrostomy (perc-G), percutaneous jejunostomy , or primary gastrojejunostomy. RESULTS: 912 patients undergoing enteral access cases met the criteria for inclusion. PEGs and perc-Gs were the most common procedures. PEGs had higher Charlson scores (4.5 [3.0-6.0] versus 2.0 [1.0-2.0], P = 0.007) and lower starting albumin (3.0 [2.6-3.4] versus 3.6 [3.5-3.8] g/dL, P < 0.0001). Time to goal feeds (4 [2-6] vs 4 [3-5] d, P = 0.970), delta prealbumin (3.6 [0-6.5] versus 6.2 [2.3-10] mg/L, P = 0.145), time to access removal (160 [60-220] versus 180 [90-300] d, P = 0.998), and enteral access-related complications (19% versus 16%, P = 0.21) between PEG and perc-G were similar and differences were not statistically significant. A greater percent change in prealbumin was noted for perc-G (10 [-3-20] versus 41.7% [11-65], P = 0.002). CONCLUSIONS: Despite having higher Charlson scores and worse preoperative nutrition, there is a similar incidence of enteral access-related complications, time to goal feeds, delta prealbumin, or time to access removal between PEG and perc-G patients. Our data suggest that access approach should be made on an individual basis, accounting for anatomy and technical feasibility.

Does Alteration of the Microbiome Cause Diverticular Disease?

The role of the microbiome in influencing the development and course of human disease is increasingly understood and appreciated. In diverticular disease, the microbiome presents an intriguing potential link between the disease and its long-established risk factors, dietary fiber and industrialization. However, current data have yet to demonstrate a clear link between specific alterations in the microbiome and diverticular disease. The largest study of diverticulosis is negative and studies of diverticulitis are small and heterogeneous. Although multiple disease-specific hurdles exist, the early state of the current research and the many un- or underexplored clinical phenotypes present a significant opportunity for investigators to improve our knowledge of this common and incompletely understood disease.

Teamwork at the Bench: Strategies for Collaborative Surgical Science in a Pandemic.

The Center for Basic and Translational Science was formed to address the unique challenges faced by surgeon-scientists. Shortly after its inception, COVID-19 upended research workflows at our institution. We discuss how the collaborative Center for Basic and Translational Science framework was adapted to support laboratories during the pandemic by assisting with ramp-down, promoting mentorship and community building, and maintaining research productivity.

Radiological assessment of persistent retroperitoneal and lateral pelvic lymph nodes after neoadjuvant therapy for rectal cancer: An analysis of the United States Rectal Cancer Consortium.

INTRODUCTION: Management of retroperitoneal and lateral pelvic lymph nodes (RLPN) in rectal cancer remains unclear. With total neoadjuvant therapy (TNT), more patients have radiologic complete clinical response (rCR). We sought to evaluate the impact of radiographic persistent RLPN after neoadjuvant therapy on survival. MATERIALS AND METHODS: Patients with rectal adenocarcinoma with isolated RLPN metastasis, who received neoadjuvant therapy before surgery were included from the United States Rectal Cancer Consortium database. Primary outcomes were recurrence-free survival (RFS) and overall survival (OS). RESULTS: Of 77 patients, all received neoadjuvant therapy, with 35 (46%) receiving TNT. Posttreatment, 33 (43%) had rCR while 44 (57%) had radiographic persistent RLPN. Median number of radiographic positive RLPN was 1 (IQR 1-2). Receipt of TNT was associated with radiographic RLPN rCR (OR 4.77, 95% CI 1.81-12.60, p < .01). However, there was no difference in RFS and OS between patients who achieved rCR or with persistent RLPN (all p > .05). CONCLUSIONS: Radiographic persistence of RLPN was not associated with worse survival in well-selected patients and may not be a reliable indicator of pathological response. TNT may be the preferred management strategy to select patients given its association with rCR. Radiographic persistence of RLPN after preoperative therapy should not necessarily preclude surgery.

Anorectal Physiology Testing for Prolapse-What Tests are Necessary?

Rectal prolapse frequently occurs in conjunction with functional and anatomic abnormalities of the bowel and pelvic floor. Prolapse surgery should have as its goal not only to correct the prolapse, but also to improve function to the greatest extent possible. Careful history-taking and physical exam continue to be the surgeon's best tools to put rectal prolapse in its functional context. Physiologic testing augments this and informs surgical decision-making. Defecography can identify concomitant middle compartment prolapse and pelvic floor hernias, potentially targeting patients for urogynecologic consultation or combined repair. Other tests, including manometry, ultrasound, and electrophysiologic testing, may be of utility in select cases. Here, we provide an overview of available testing options and their individual utility in rectal prolapse.

NCCN Guidelines Insights: Colorectal Cancer Screening, Version 2.2020.

The NCCN Guidelines for Colorectal Cancer (CRC) Screening describe various colorectal screening modalities as well as recommended screening schedules for patients at average or increased risk of developing sporadic CRC. They are intended to aid physicians with clinical decision-making regarding CRC screening for patients without defined genetic syndromes. These NCCN Guidelines Insights focus on select recent updates to the NCCN Guidelines, including a section on primary and secondary CRC prevention, and provide context for the panel's recommendations regarding the age to initiate screening in average risk individuals and follow-up for low-risk adenomas.

Surgical Resection for Primary Rectal Lymphoma: Support for Local Excision?

BACKGROUND: Primary rectal lymphoma is an uncommon and heterogeneous malignancy. Because of its rarity, few data exist to guide treatment or counsel patients. We present the largest series to date of patients undergoing nonpalliative surgery for rectal lymphoma. We hypothesize that there will be no difference in overall survival between patients undergoing local resection (LR) or radical resection (RR). MATERIALS AND METHODS: The National Cancer Data Base was queried for all cases of resected primary rectal lymphoma between years 2004 and 2014. Exclusion criteria included patients with stage IV disease and those operated on for palliation. Patients were categorized by resection approach-LR or RR. Approach along with demographic, histologic, and hospital-level factors were analyzed with a Cox proportional hazard analysis. RESULTS: A total of 233 patients were identified. Mean age was 63 y (interquartile range 53-73), and 57% of the population was female. The most common histologic subtypes were marginal (44%), diffuse large B-cell (20%), and follicular lymphoma (17%). Eighty-seven percent underwent LR. There was no significant difference in R0 resection (LR: 38% versus RR: 58%; P = 0.07), adjuvant chemotherapy (LR: 18% versus RR: 29%; P = 0.22), or adjuvant radiation (LR: 21% versus RR: 16%; P = 0.63) between the groups. Five-year overall survival was 79%, and there was no significant difference in approach (LR: 81% versus RR: 56%, P = 0.06). Multivariable analysis did not identify an association between approach and overall survival. CONCLUSIONS: Surgical resection of rectal lymphoma is rare. Our data support consideration of LR when possible, given the lack of convincing survival benefit of radical surgery or R0 resection.

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.

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.

Seasonal Variation in Diverticulitis: Evidence From Both Hemispheres.

BACKGROUND: Diverticulitis is a common and morbid disease with incompletely understood risk factors and pathophysiology. Geographic and, recently, seasonal trends in diverticulitis have been described in the United States. OBJECTIVE: The purpose of this study was to investigate and compare seasonal trends in urgent hospital admission for diverticulitis in geographically distinct populations in the northern and southern hemispheres. DESIGN: Inpatient, urgent admissions for diverticulitis were identified within the Dr Foster Intelligence Global Comparators Dataset, a global benchmarking collaborative. SETTINGS: Admissions to participating hospitals in the United Kingdom, Australia, and the United States were identified between 2008 and 2013. PATIENTS: A total of 18,672 urgent admissions for diverticulitis were identified among 5.5-million admissions. MAIN OUTCOME MEASURES: Four separate hypothesis testing methods were used to identify seasonal trends in diverticulitis admissions among international patient populations. RESULTS: Seasonal trends were present in all 3 countries. A summer peak was observed in both hemispheres using multiple statistical testing methods. Logistic regression analyses identified summer months as significantly associated with diverticulitis admission in all 3 countries. LIMITATIONS: This study is limited by restriction to inpatient admissions, reliance on administrative data, and participation of select hospitals within the database. CONCLUSIONS: These data suggest a shared seasonal risk factor among geographically distinct populations for diverticulitis.

Tumors of the neural crest: Common themes in development and cancer.

The neural crest (NC) is a remarkable transient structure in the vertebrate embryo that gives rise to a highly versatile population of pluripotent cells that contribute to the formation of multiple tissues and organs throughout the body. In order to achieve their task, NC-derived cells have developed specialized mechanisms to promote (1) their transition from an epithelial to a mesenchymal phenotype, (2) their capacity for extensive migration and cell proliferation, and (3) their ability to produce diverse cell types largely depending on the microenvironment encountered during and after their migratory path. Following embryogenesis, these same features of cellular motility, invasion, and proliferation can become a liability by contributing to tumorigenesis and metastasis. Ample evidence has shown that cancer cells have cleverly co-opted many of the genetic and molecular features used by developing NC cells. This review focuses on tumors that arise from NC-derived tissues and examines mechanistic themes shared during their oncogenic and metastatic development with embryonic NC cell ontogeny.

Readmission After Resections of the Colon and Rectum: Predictors of a Costly and Common Outcome.

BACKGROUND: Readmission rates are a measure of surgical quality and an object of clinical and regulatory scrutiny. Despite increasing efforts to improve quality and contain cost, 6% to 25% of patients are readmitted after colorectal surgery. OBJECTIVE: The aim of this study is to define the predictors and costs of readmission following colorectal surgery. DESIGN: This is a retrospective cohort study of patients undergoing elective and nonelective colectomy and/or proctectomy in the Healthcare Cost and Utilization Project Florida State Inpatient Database 2007 to 2011. Readmission is defined as inpatient admission within 30 days of discharge. Univariate analyses were performed of sex, age, Elixhauser score, race, insurance type, procedure, indication, readmission diagnosis, cost, and length of stay. Multivariate analysis was performed by logistic regression. Sensitivity analysis of nonemergent admissions was conducted. SETTINGS: This study was conducted in Florida acute-care hospitals. PATIENTS: Patients undergoing colectomy and proctectomy from 2007 to 2011 were included. INTERVENTION(S): There were no interventions. MAIN OUTCOME MEASURE(S): The primary outcomes measured were readmission and the cost of readmission. RESULTS: A total of 93,913 patients underwent colectomy; 14.7% were readmitted within 30 days. From 2007 to 2011, readmission rates remained stable (14.6%-14.2%, trend p = 0.1585). After multivariate adjustment, patient factors associated with readmission included nonwhite race, age <65, and a diagnosis code other than neoplasm or diverticular disease (p < 0.0001). Patients with Medicare or Medicaid were more likely to be readmitted than those with private insurance (p < 0.0001). Patients with longer index admissions, those with stomas, and those undergoing all procedures other than sigmoid or transverse colectomy were more likely to be readmitted (p < 0.0001). High-volume hospitals had higher rates of readmission (p < 0.0001). The most common reason for readmission was infection (32.9%). Median cost of readmission care was $7030 (intraquartile range, $4220-$13,247). Fistulas caused the most costly readmissions ($15,174; intraquartile range, $6725-$26,660). LIMITATIONS: Administrative data and retrospective design were limitations of this study. CONCLUSIONS: Readmissions rates after colorectal surgery remain common and costly. Nonprivate insurance, IBD, and high hospital volume are significantly associated with readmission.