Neoplasia in inflammatory bowel disease: surveillance and management strategies

Role of endoscopy in inflammatory bowel disease

Crohn’s disease (CD) and ulcerative colitis (UC) constitute the two most common phenotypes of inflammatory bowel disease (IBD). Ileocolonoscopy with biopsy has been considered the gold standard for the diagnosis of IBD. Differential diagnosis of CD and UC is important, as their medical and surgical treatment modalities and prognoses can be different. However, approximately 15% of patients with IBD are misdiagnosed as IBD unclassified due to the lack of diagnostic certainty of CD or UC. Recently, there has been increased recognition of the role of the therapeutic endoscopist in the field of IBD. Newer imaging techniques have been developed to aid in the differentiation of UC vs CD. Furthermore, endoscopic balloon dilation and stenting have become an integral part of the therapeutic armamentarium of CD stricture management. Endoscopic ultrasound has been recognized as being more accurate than magnetic resonance imaging in detecting perianal fistulae in patients with CD. Additionally, chromoendoscopy may help to detect dysplasia earlier compared with white-light colonoscopy. Hence, interventional endoscopy has become a cornerstone in the diagnosis, treatment and management of IBD complications. The role of endoscopy in the field of IBD has significantly evolved in recent years from small-bowel imaging to endoscopic balloon dilation and use of chormoendoscopy in dysplasia surveillance. In this review article, we discuss the current evidence on interventional endoscopy in the diagnosis, treatment and management of IBD compications.

Impact of mucosal inflammation on risk of colorectal neoplasia in patients with ulcerative colitis: a systematic review and meta-analysis

BACKGROUND AND AIMS

Long-standing ulcerative colitis is an established risk factor for colorectal neoplasia. A number of observational studies have suggested that evidence of mucosal inflammation (endoscopic or histologic) is associated with a greater risk for colorectal neoplasia than is mucosal healing. Our goal was to systematically analyze the risk of colorectal neoplasia in patients with ulcerative colitis who have ongoing mucosal inflammation to better inform surveillance strategies.

METHODS

We performed a systematic review and meta-analysis of the effect of endoscopic and/or histologic inflammation on the risk of colorectal neoplasia in cohort and case-control studies. Sensitivity analyses for study setting and case definition were performed.

RESULTS

Six studies met the inclusion criteria, incorporating outcomes in 1443 patients. No study used a single validated measure for mucosal inflammation. The pooled odds ratio for colorectal neoplasia was 3.5 (95% confidence interval [CI], 2.6-4.8; P < .001) in those with any mucosal inflammation and 2.6 (95% CI, 1.5-4.5; P = .01) in those with histologic inflammation, when compared with those with mucosal healing. The overall quality of the studies was good.

CONCLUSION

The presence of objective evidence of mucosal inflammation during follow-up in patients with ulcerative colitis is associated with a greater risk of subsequent colorectal neoplasia than in those with mucosal healing. This risk factor should be considered in guidelines on surveillance intervals for these patients.

Surgical aspects of inflammatory bowel diseases in pediatric and adolescent age groups

BACKGROUND

Inflammatory bowel disease (IBD) is increasingly encountered in children. Early disease is associated with higher complication rate with increased incidence of surgical intervention.

PATIENTS AND METHODS

From January 2010 to June 2015, 25 patients in the pediatric and adolescent age groups with IBD underwent surgical intervention in our center. They were classified into two groups. Group I included 15 patients with ulcerative colitis where 5 cases had left colon disease underwent left colectomy, while 10 cases had pancolonic disease underwent total colectomy and anal mucosectomy with ileo-anal or ileal pouch-anal anastomosis with covering ileostomy. Group II included 10 cases with Crohn's disease where the indications for surgery were intestinal obstruction in seven cases, fulminant perianal infection with septic shock in one, perianal fistula and ulcers in one, and growth failure due to resistant intestinal fistula in one.

RESULTS

Group I included eight males and seven females; mean age at surgery was 10.6 years. There were postoperative complications in seven cases in the form of pelvic abscess and wound infection in one, wound infection in two, and recurrent pouchitis in four cases. Group II contained eight males and two females; mean age at surgery was 6.6 years. Two cases had recurrent symptoms after stricturoplasty. The mean length of time from diagnosis to surgery was 2.4 years (ranging from 6 to 36 months).

CONCLUSION

A multidisciplinary team is mandatory for proper management of IBD cases. The risk of the disease and the expected surgical complications determine the timing of surgical interference.

Surgery for Crohn's disease and anti-TNF agents: the changing scenario

Surgery has been a mainstay of therapy for Crohn's disease for a long time, essentially as a consequence of the fairly modest efficacy of traditional medications such as immunomodulators, antibiotics and 5-ASA, especially in severe cases. However, in the past decade and half, the advent of anti-TNF agents has greatly changed the medical approach to this disease and may modify its general management as well. Here, we have reviewed the current literature on incidence of surgery, timing of surgery and postoperative recurrence of Crohn's disease before and after the advent of anti-TNF agents. In addition, we have reviewed the risk of perioperative complications in patients on anti-TNF agents before surgery. The data show that the use of these medications is changing or expecting to change shortly a number of surgical aspects of Crohn's disease management.

Review Paper: Implications of the “Cancer Stem Cell” Hypothesis on Murine Models of Colon Cancer and Colitis-associated Cancer

The use of murine models to investigate human diseases has been an invaluable tool. In the areas of inflammation and oncogenesis, such models have provided unique insights into pathogenesis and mechanisms to evaluate potential therapy. As such, one facet of these disease processes links inflammation and cancer. Inflammation is associated with at least 15% of the world's malignancies. One example of this relationship is documented in the association between colitis and colorectal cancer. To date, the precise molecular events linking inflammation and cancer remain unclear. A new paradigm that may bridge these processes includes the cancer stem cell hypothesis. In this review, murine models of colitis, colon cancer, and colitis-associated cancer are discussed in reference to the potential of this paradigm to clarify the relationship of these devastating diseases.

Colonic crypt organization and tumorigenesis

An appreciation of colonic crypt organization has become essential to any understanding of tumorigenesis in the colon. Intestinal crypts house tissue-specific, multipotential stem cells, which are located in the niche at the base of the intestinal crypt and are capable of regenerating all intestinal cell types. Recent advances in our understanding of crypt biology, including how mutations in stem cells become fixed and expand within the epithelium, has led to new theories on the origins of colonic adenomas and cancers.

Diagnostics of inflammatory bowel disease

The diagnosis of inflammatory bowel disease (IBD) with its 2 main subforms, Crohn's disease and ulcerative colitis, is based on clinical, endoscopic, radiologic, and histologic criteria. This paradigm remains unchanged despite the advent of new molecular technologies for the examination of serum proteins and genetic sequences, respectively. The main innovations in diagnostic technologies include the development of more sophisticated endoscopic and noninvasive imaging techniques with the aim of improving the identification of complications, in particular malignant diseases associated with IBD. The future will see further progress in the identification of genetic susceptibility factors and of protein biomarkers and their use to describe the molecular epidemiology of IBD. It can be expected that future diagnostic algorithms will include molecular parameters to detect early disease or guide therapies by predicting the individual course of disease.

Inflammatory bowel disease in the pediatric patient

Inflammatory bowel disease (IBD) is a general term used to describe two chronic bowel disorders, Crohn's disease (CD) and ulcerative colitis (UC), both of which are characterized by autoimmune-related inflammation of the intestines. UC is limited to the colonic mucosa, whereas CD can involve any part of the intestinal tract from the mouth to the anus. The true etiology of UC and CD is still unknown, although extensive research has identified some genetic and environmental factors. This article discusses current clinical concepts of both diseases in the pediatric population.