The Significance of Sessile Serrated Polyps in Inflammatory Bowel Disease

Interobserver agreement of the modified Paris classification and histology prediction of colorectal lesions in patients with inflammatory bowel disease

BACKGROUND AND AIMS

SCENIC (International Consensus Statement on Surveillance and Management of Dysplasia in IBD) guidelines recommend that visible dysplasia in patients with longstanding inflammatory bowel disease (IBD) should be endoscopically characterized using a modified Paris classification. This study aimed to determine the interobserver agreement (IOA) of the modified Paris classification and endoscopists' accuracy for pathology prediction of IBD visible lesions.

METHODS

One hundred deidentified endoscopic still images and 30 videos of IBD visible colorectal lesions were graded by 10 senior and 4 trainee endoscopists from 5 tertiary care centers. Endoscopists were asked to assign 4 classifications for each image: the standard Paris classification, modified Paris classification, pathology prediction, and lesion border. Agreement was measured using Light's kappa coefficient. Consensus of ratings was assessed according to strict majority.

RESULTS

The overall Light's kappa for all study endpoints was between .32 and .49. In a subgroup analysis between junior and senior endoscopists, Light's kappa continued to be less than .6 with a slightly higher agreement among juniors. Lesions with the lowest agreement and no consensus were mostly classified as Is, IIa, and mixed Paris classification and sessile and superficial elevated for modified Paris classification. Endoscopist accuracy for prediction of dysplastic, nondysplastic, and serrated pathology was 77%, 56%, and 30%, respectively. There was a strong association (P < .001) between the given morphology classification and the predicted pathology with Ip lesions carrying a much lower expectation of dysplasia than Is/IIc/III and mixed lesions. The agreement for border prediction was .5 for junior and .3 for senior endoscopists.

CONCLUSIONS

This study demonstrates very low IOA for Paris and modified Paris classifications and low accuracy and IOA for lesion histopathology prediction. Revisions of these classifications are required to create a clinically useful risk stratification tool and enable eventual application of augmented intelligence tools.

Serrated polyps in patients with ulcerative colitis: Unique clinicopathological and biological characteristics

BACKGROUND

Serrated polyps have recently been reported in patients with ulcerative colitis (UC); however, their prevalence and detailed characteristics remain unclear.

METHODS

The prevalence and clinicopathological and biological characteristics of serrated polyps in patients with UC were retrospectively examined in a single tertiary inflammatory bowel disease center in Japan from 2000 to 2020.

RESULTS

Among 2035 patients with UC who underwent total colonoscopy, 252 neoplasms, including 36 serrated polyps (26 in colitis-affected segments, 10 in colitis-unaffected segments), were identified in 187 patients with UC. The proportion of serrated polyps was 1.8% (36/2035). Serrated polyps in colitis-affected segments were common with extensive colitis (88%), history of persistent active colitis (58%), and long UC duration (12.1 years). Serrated polyps in colitis-affected segments were more common in men (88%). Of the 26 serrated polyps in colitis-affected segments, 15, 6, and 5 were categorized as sessile serrated lesion-like dysplasia, traditional serrated adenoma-like dysplasia, and serrated dysplasia not otherwise specified, respectively. Sessile serrated lesion-like dysplasia was common in the proximal colon (67%) and with BRAF mutation (62%), whereas traditional serrated adenoma-like dysplasia and serrated dysplasia not otherwise specified were common in the distal colon (100% and 80%, respectively) and with KRAS mutations (100% and 75%, respectively).

CONCLUSIONS

Serrated polyps comprised 14% of the neoplasias in patients with UC. Serrated polyps in colitis-affected segments were common in men with extensive and longstanding colitis, suggesting chronic inflammation in the development of serrated polyps in patients with UC.

Incremental Detection Rate of Dysplasia and Sessile Serrated Polyps/Adenomas Using Narrow-Band Imaging and Dye Spray Chromoendoscopy in Addition to High-Definition Endoscopy in Patients with Long-Standing Extensive Ulcerative Colitis: Segmental Tandem Endoscopic Study

High-definition (HD) endoscopy is recommended in surveillance colonoscopy for detecting dysplasia in patients with ulcerative colitis (UC). Dye-spray chromoendoscopy (DCE) and narrow-band imaging (NBI) are often used as adjunctive techniques of white-light endoscopy (WLE) in real-world practice. However, the incremental detection ability of DCE and NBI added to HD-WLE for dysplasia and serrated lesions has not yet been evaluated using tandem endoscopy in patients with long-standing extensive UC. We enrolled patients with extensive UC for >8 years who were in clinical remission (partial Mayo score < 2) at the Samsung Medical Center in Seoul, Republic of Korea. HD-WLE was performed first. Subsequently, HD-NBI and HD-DCE with indigo carmine were performed using the segmental tandem colonoscopy technique. A total of 40 patients were eligible, and data obtained from 33 patients were analyzed. The incremental detection rates (IDRs) for dysplasia and serrated lesions were calculated. HD-WLE detected three dysplasia and five sessile serrated adenomas/polyps (SSAs/Ps). HD-NBI and HD-DCE did not detect additional dysplasia (IDR = 0%; 95% confidence interval (CI): 0-56.2%). HD-NBI identified one missed SSA/P (IDR = 7.7%; 95% CI: 1.4-33.3%), and HD-DCE detected seven missed SSAs/Ps (IDR = 53.9%; 95% CI: 29.1-76.8%). Logistic regression found that HD-DCE increased the detection of SSAs/Ps compared to HD-WLE and/or HD-NBI (odds ratio (OR) = 3.16, 95% CI: 0.83-11.92, p = 0.08). DCE in addition to HD-WLE improved the detection of SSAs/Ps, but not dysplasia, in patients with long-standing extensive UC.

Influence of SCENIC recommendations on terminology used for histopathologic diagnosis of inflammatory bowel disease-associated dysplasia

BACKGROUND

Published in 2015, the International Consensus Recommendations on Surveillance for Colorectal Endoscopic Neoplasia Detection and Management in Inflammatory Bowel Disease Patients (SCENIC) recommended abandoning the use of diagnostic term “dysplasia-associated lesion or mass (DALM)” for polypoid dysplastic lesions detected in patients with inflammatory bowel disease (IBD). The aim of this study was to investigate whether this recommendation had any influence on diagnostic terminologies used by pathologists in their practice.

METHODS

We retrospectively reviewed all pathology reports for surveillance colonoscopic biopsies from ulcerative colitis (UC) patients in our institution during 1/2012-12/2014 (pre-SCENIC) and 1/2016-12/2018 (post-SCENIC). These included 1203 biopsies from 901 UC patients during the pre-SCENIC period and 1273 biopsies from 977 UC patients during the post-SCENIC period. Their corresponding endoscopic findings and histopathologic diagnoses were recorded. Clinical indications for total colectomy for UC patients and corresponding histopathologic findings in colectomy specimens were also recorded and compared.

RESULTS

A total of 347 and 419 polyps/polypoid lesions were identified during the pre-SCENIC and post-SCENIC periods, among which 60 and 104 were dysplastic/ adenomatous, respectively. More polypoid dysplastic lesions were simply diagnosed as “adenoma” during the post-SCENIC period in comparison with the pre-SCENIC period (97.1% vs 65.0%; P < 0.001). The number of cases with a comment in pathology reports regarding the distinction between DALM and sporadic adenoma was also significantly decreased during the post-SCENIC period (5.8% vs 38.3%; P < 0.001). In addition, the term “dysplasia” was more consistently used for random biopsies during the post-SCENIC period. Furthermore, the terms “sessile serrated adenoma/polyp” (SSA/P) and “serrated epithelial change” (SEC) were more consistently used for polypoid lesions and random biopsies, respectively, during the post-SCENIC period, although these were not specifically addressed in the SCENIC recommendations. The indications for colectomy remained unchanged, however, despite the standardization of diagnostic terminologies.

CONCLUSION

The SCENIC recommendations relieve pathologists from the burden of distinguishing DALM from sporadic adenoma in IBD patients, which helps the standardization of diagnostic terminologies used by pathologists. The consistent use of the diagnostic terminologies may help reduce potential confusions to clinicians and patients.

Sampling and Reporting of Inflammatory Bowel Disease

Pathologists have an important and expanding role in the diagnosis and management of inflammatory bowel disease. This role includes the initial diagnosis of the disease, assessment of the response to treatment and the identification of short-term complications such as cytomegalovirus infection and long-term complications such as dysplasia. Furthermore, the assessment of resection specimens for complication of disease is important to determining the risk of subsequent disease or inflammation within an ileal pouch. Adequate sampling of the disease at endoscopy and from the surgical resection specimen is vital to determining the ultimate information that can be provided by the pathologist. This sampling is determined by the clinical scenario. Similarly, a standardized approach to reporting and synthesizing the histologic findings will improve patient management. This is best exemplified by the increasing interest in histologic activity indices, such as the Nancy index in ulcerative colitis, and in the standardized reporting for inflammatory bowel disease dysplasia recommended by the SCENIC international consensus.

Increased Colorectal Neoplasia Risk in Patients with Inflammatory Bowel Disease and Serrated Polyps with Dysplasia

BACKGROUND

The impact of serrated polyps on the advanced colorectal neoplasia (CRN) risk in inflammatory bowel disease (IBD) patients is unknown. Serrated polyps are histologically categorized as hyperplastic polyps (HPs), sessile serrated lesions (SSLs), and traditional serrated adenomas (TSAs).

AIMS

We aimed (1) to characterize the serrated polyps in IBD patients, (2) to identify factors associated with the presence of serrated polyps in IBD, and (3) to assess the CRN risk in IBD patients with serrated polyps.

METHODS

We established a retrospective cohort of IBD patients with and without colonic serrated polyps. Cox-regression analysis with time-dependent variables was used to compare advanced CRN risk in IBD patients with and without serrated polyps.

RESULTS

Of the 621 enrolled IBD patients, 198 had a serrated polyp (92 HPs, 88 SSLs without dysplasia, 13 SSLs with dysplasia, and 5 TSAs). Independent factors associated with serrated polyps were ulcerative colitis (UC) (odds ratio (OR) 1.77, 95% confidence interval (CI) 1.19-2.62, p = 0.005), male gender (OR 1.63, 95% CI 1.11-2.40, p = 0.013), and older age (per year increase, OR 1.06, 95%CI 1.05-1.08, p < 0.001). TSAs and SSLs with dysplasia were risk factors for subsequent advanced CRN (HR 13.51, 95% CI 3.11-58.68, p < 0.001), while HPs (HR 1.98, 95% CI 0.46-8.60, p = 0.36) and SSLs without dysplasia (HR 0.87, 95% CI 0.11-6.88, p-0.89) did not impact the subsequent advanced CRN risk.

CONCLUSIONS

UC, male gender and older age were associated with the presence of serrated polyps. The majority of serrated polyps (91%) were HPs and SSL without dysplasia and did not affect the CRC risk. However TSAs and SSLs with dysplasia, representing a small subgroup of serrated polyps (9%), were associated with subsequent advanced CRN.

Ulcerative Colitis With Concomitant Serrated Polyposis Syndrome: A Case Report and Literature Review

Serrated polyposis syndrome (SPS) is a pre-cancerous condition associated with increased risk of developing colorectal cancer (CRC). Its role in inflammatory bowel disease (IBD)-associated CRC remains unknown. Despite the growing understanding and recognition of SPS, there is limited literature about its impact on the colon in individuals with IBD. Herein, we report a case of a 45-year-old female who was diagnosed with ulcerative colitis (UC) and SPS. We also reviewed the literature surrounding this association and highlighted the intricacies in managing this unique patient population. At present, there are no screening guidelines for CRC in SPS patients with IBD. However, given the potential synergistic risk for CRC, a close surveillance approach may be utilized. Tracking lifetime cumulative features of SPS and endoscopic clearance of adenomas and serrated polyps are the mainstays of management.

Advanced neoplasia detection using chromoendoscopy and white light colonoscopy for surveillance in patients with inflammatory bowel disease

Background/Aims

Chromoendoscopy (CE) has been shown to be superior to white light endoscopy (WLE) for neoplasia detection in inflammatory bowel disease (IBD). We aimed to compare the yield of CE and WLE for the detection of overall neoplasia and advanced neoplasia in IBD.

Methods

Patients who underwent surveillance colonoscopy from 1999 to 2017 were identified from our IBD database. CE procedures were compared with their respective WLE controls in a paired comparison, and frequency of all neoplasia, advanced neoplasia, and serrated neoplasia was assessed for both targeted and random biopsies.

Results

A total of 290 procedures performed in 98 individuals were identified with a median follow-up 4 years (median 3 colonoscopies/patient). CE and WLE were performed in 159 and 131 episodes, respectively. CE detected neoplasia in 40.9% of colonoscopies versus 23.7% with WLE (P= 0.002). In addition, CE detected more advanced neoplasia (18.2% vs. 6.1%, P= 0.002) and serrated lesions (14.5% vs. 6.1%, P= 0.022). Significantly fewer samples were obtained per procedure with CE (14.9 ± 9.7 vs. 20.9 ± 11.1, P< 0.001). Cancer was diagnosed in 2 cases.

Conclusions

CE has a higher detection rate than WLE for advanced neoplasia and serrated lesions in patients with IBD under surveillance. Further prospective studies evaluating the impact of CE on decreasing the risk of interval cancer and colectomy in IBD patients are warranted.

Serrated Lesions in Inflammatory Bowel Disease: Genotype-Phenotype Correlation

BACKGROUND

Patients with inflammatory bowel disease (IBD) and hyperplastic/serrated polyposis have an increased risk of colorectal cancer. The aim of our study was to elucidate the nature of serrated lesions in IBD patients.

MATERIALS AND METHODS

Sixty-five lesions with serrated morphology were analyzed in 39 adult IBD patients. Lesions were classified according to the WHO 2019 criteria or regarded as reactive, and molecular analysis was performed.

RESULTS

82.1% of patients had ulcerative colitis, 17.9% had Crohn's disease; 51.3% were female, and the mean age was 54.5 years. The duration of IBD varied significantly (16.7 ± 11.4 years). Endoscopy showed polypoid lesions in 80.3%; the size ranged from 2 to 20 mm. A total of 21.6% of the lesions were located in the right colon. Five lesions were classified as inflammatory pseudopolyps, 28 as hyperplastic polyp, 21 and 2 as sessile serrated lesion without and with dysplasia, respectively, and 9 as traditional serrated adenoma with low-grade dysplasia. Analysis of all true serrated lesions revealed 31 mutations in KRAS and 32 in BRAF gene. No mutations were identified in inflammatory pseudopolyps. In the right colon BRAF mutations were more frequent than KRAS (16 vs 3), while KRAS mutations prevailed on the left side (28 vs 16, P < .001). One patient with traditional serrated adenomas progressed to an adenocarcinoma after 61 months.

CONCLUSION

The molecular analysis could help discriminate true serrated lesions (IBD-associated or not) from reactive pseudopolyps with serrated/hyperplastic epithelial change. These should help in more accurate classification of serrated lesions.

Diagnostic interobserver variability in Crohn's disease- and ulcerative colitis-associated dysplasia: a multicenter digital survey from the IG-IBD Pathologists Group

BACKGROUND

Crohn's disease (CD) and ulcerative colitis, two forms of inflammatory bowel disease (IBD), are chronic and relapsing conditions of the gastrointestinal tract both characterized by long lasting chronic inflammation and increased risk of dysplasia and colorectal cancer (CRC). The aim of our study was to evaluate the interobserver agreement about IBD-associated dysplasia among pathologists belonging to the Italian Group for Inflammatory Bowel Diseases (IG-IBD P).

METHODS

The present multicenter survey was performed using telepathology, supported by an open source E-learning platform. Biopsy specimens from 30 colonoscopies and from 20 patients were included. The glass slides of any case, including clinical and endoscopic data, were digitalized and uploaded on the E-learning platform. All the digital slides were grouped in 54 diagnostic "blocks". Blinded histopathological evaluation on all the digital slides was performed by 20 gastrointestinal pathologists. Closed-ended questions about (1) the occurrence of IBD; (2) the classification of IBD (as UC or CD); (3) the presence of active versus quiescent disease; (4) the presence of dysplasia; (5) the possible association of dysplasia with the sites of disease (dysplasia-associated lesion or mass-DALM vs adenoma-like mass-ALM); (6) the grading of dysplasia according to the ECCO guidelines (negative, indefinite, low grade, high grade categories) and (7) the presence of associated serrated features, were proposed in each case. Inter-observer agreement was evaluated by mean agreement percentage and kappa statistic, when suitable.

RESULTS

The diagnosis of IBD was confirmed in 19 of 20 patients, 17 of 19 being classified as UC, 2 as CD. The mean interobserver agreement percentages about (1) the evidence of IBD, (2) the presence of either UC or CD and (3) the activity grading resulted to be 80%, 69% and 86%, respectively. Dysplasia was detected in 8/20 patients, with moderate agreement between pathologists (mean 72%, k 0.48). Particularly, low grade dysplasia was found in 13 biopsies (combined k 0.38), whereas high grade dysplasia in 8 (combined k 0.47). When the endoscopic and histopathological data were combined, features consistent with DALM were found in 6 of 20 patients with low grade dysplasia and those consistent with ALM in 2 patients with low grade dysplasia in a single biopsy (mean agreement: 86%). An associated serrated pattern was discovered in 4 patients (7 biopsies).

CONCLUSIONS

Our study showed moderate interobserver agreement about the histopathological detection and classification of IBD-associated dysplasia. Further efforts should be undertaken to integrate the histopathological data with both the ancillary tests and molecular investigations.

Significance of serrated epithelial change in inflammatory bowel disease

OBJECTIVES

The clinical significance of hyperplastic polyp-like histologic changes in random biopsy samples ('serrated epithelial change' or SEC) from patients with inflammatory bowel disease (IBD) remains uncertain, with some studies suggesting an increased risk of dysplasia and even carcinoma. Controlled studies are few. We studied the significance of SEC on the development of dysplasia in follow-up surveillance of IBD patients in our system.

METHODS

We identified 94 IBD patients with SEC and 187 IBD patients without SEC identified in index biopsy samples, and retrospectively collated results of follow-up surveillance samples in each group, with the development of dysplasia and/or adenocarcinoma as study endpoints.

RESULTS

IBD patients with SEC had a 12.8% likelihood of developing dysplasia of any type within IBD-affected areas vs a 4.3% likelihood in non-SEC patients (follow-up in the 1-4 year range for each group). This was significant in univariate analysis (p = 0.013) but not in multivariate analysis, likely due to increased frequency of follow-up sampling in the SEC patients. One cancer developed in each group (p = NS).

CONCLUSION

Our data, in the context of other studies, neither prove nor conclusively exclude an increased risk of dysplasia in IBD patients with SEC. But cancer risk appears low and continued surveillance at usual intervals seems reasonable.

Revisiting the distinct histomorphologic features of inflammatory bowel disease-associated neoplastic precursor lesions in the SCENIC and post-DALM Era

Distinct histomorphologic features of colitis-associated dysplasia (CAD) or neoplastic precursors in inflammatory bowel disease (IBD) have never been clearly identified. In this study, we tried to further explore the differentiating morphologic features of CAD by retrospectively reviewing the lesions that were clearly associated with carcinomas (carcinoma-related lesions) and by comparing between endoscopically nonpolypoid (non-adenoma-like) lesions and polypoid (adenoma-like) lesions and sporadic conventional adenomas found in the noncolitic mucosa and in patients without IBD. Our study results have revealed that (1) precursor lesions related to IBD-associated colorectal carcinomas were almost always nonpolypoid in macroscopic/endoscopic appearance; (2) nearly half of the carcinoma-related lesions and nonpolypoid lesions were similarly nonadenomatous (nonconventional) lesions, largely serrated type, with no or only mild/focal adenomatous dysplasia, and commonly had mixed adenomatous and nonadenomatous features; (3) carcinoma-related and nonpolypoid adenomatous dysplastic lesions frequently showed some peculiar histocytologic features that we observed and described for the first time, including mixed features of inflammatory pseudopolyps or granulation tissue, pleomorphic and disarrayed nuclei, micropapillary or hobnailing surface epithelial cells, and microvesicular or bubbling cytoplasm of dysplastic cells; and (4) polypoid lesions in the colitic mucosa were identical to sporadic adenomas in the noninflamed mucosa and in patients without IBD, and they lacked the aforementioned features. The seemingly distinctive morphologic characteristics that we proposed here, although still not absolutely specific or unique, can be used as the features of inclusion for identifying CAD on endoscopic biopsies when the endoscopy images are not readily available to pathologists and thus to alert clinicians for a closer follow-up.

Traditional serrated adenoma-like lesions in patients with inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) have an increased risk of colorectal carcinoma. The significance of serrated lesions resembling traditional serrated adenoma (TSA) in IBD patients is unclear. In this retrospective study, we analyzed 52 TSA-like lesions arising in 30 IBD patients and diagnosed in colectomy or endoscopic specimens. The 27 colectomy lesions presented predominantly as ill-defined areas with granular appearance, with a median size of 15 mm, located throughout the large bowel and associated with synchronous advanced colorectal lesions in 58%. Low-grade serrated dysplasia was present in 56%, high-grade serrated dysplasia in 37%, and TSA-type cytology in 7%. Increased Ki-67 immunostaining and abnormal p53 expression were identified in 96% and 48%, respectively; 74% had a KRAS mutation, and 4% had a BRAF mutation. Endoscopically resectable TSA-like lesions were all discrete polypoid lesions, smaller in size (median 9 mm), predominantly in the distal large bowel, with an adjacent precursor polyp in 24%, and associated with synchronous and metachronous advanced colorectal lesions in 6%. Most (92%) show TSA-type cytology. p53 overexpression was present in 4%, KRAS mutation in 41%, and BRAF mutation in 32%. None of the 52 TSA-like lesions demonstrated loss of MLH1 or SATB2 expression by immunohistochemistry. On follow-up, 4 patients were diagnosed with colorectal carcinoma or high-grade adenomatous IBD-associated dysplasia. None of the patients with lesions showing TSA-type cytology only developed an advanced lesion. Our findings suggest that some TSA-like lesions, essentially from colectomy, may represent a form of IBD-associated dysplasia associated with an increased risk of advanced neoplasia.

Newly recognized non-adenomatous lesions associated with enteric carcinomas in inflammatory bowel disease - Report of six rare and unique cases

It is the current view that the inflammatory bowel disease (IBD)-associated precancerous lesions may be adenomatous (with classic cytologic dysplasia) and non-adenomatous (without frank cytologic dysplasia), and the latter ones are in various histomorphologies including serrated, mucinous, eosinophilic (goblet cell deficient), and differentiated (dysplasia with terminal epithelial differentiation) types. By retrospectively reviewing the surgically resected IBD-associated colorectal and ileal carcinomas (×53), analyzing the background epithelial changes/lesions in the mucosa surrounding and adjacent to invasive carcinomas, and testing the key molecular profile (KRAS, BRAF, PIK3CA, NRAS, p53, mismatch repair proteins, and SAT-B2) known to be involved in colorectal carcinogenesis, we identified 6 representative, rare and unique cases, in which non-adenomatous lesions were clearly in vicinity and in transition to invasive carcinomas. Furthermore, we identified certain colonic carcinoma-related molecular alterations, and thus further confirmed the neoplastic nature of various non-adenomatous lesions. It was also revealed that non-adenomatous lesions are heterogeneous in both morphology and molecular alterations, and that it is common to have more than one type of lesions be associated with a carcinoma. Moreover, mixed focal adenomatous dysplasia was common, which may be the necessary step in the malignant transformation of the non-adenomatous lesions.

Histological and molecular diversity and heterogeneity of precancerous lesions associated with inflammatory bowel diseases

AIMS

Inflammatory bowel disease (IBD)-associated precancerous lesions may be adenomatous or non-adenomatous with various histomorphologies. We aim to validate the newly proposed classification, to explore the neoplastic nature of the non-adenomatous lesions and to elucidate the molecular mechanisms underlying the different histomorphologies.

METHODS

44 background precursor lesions identified in 53 cases of surgically resected IBD-associated colorectal and ileal carcinomas were reviewed for the histomorphological features (classified into adenomatous, mucinous, sessile serrated adenoma (SSA)-like, traditional serrated adenoma-like, differentiated, eosinophilic and serrated not otherwise specified (NOS)) and analysed for a key panel of colonic cancer-related molecular markers.

RESULTS

Approximately 60% of the lesions were adenomatous, of which some had mixed serrated, mucinous or eosinophilic changes. The remaining non-adenomatous lesions, including all other types except SSA-like type, mostly showed mixed features and focal adenomatous dysplasia. KRAS mutation and p53 mutant-type expression were found in about half cases across all types, while PIK3CA mutation only in some of adenomatous and eosinophilic lesions and MLH1/PMS2 loss in a subset of adenomatous, mucinous and eosinophilic but not in differentiated and serrated lesions. SAT-B2 or PTEN loss and IMP3 overexpression were seen in a small subset of lesions. No BRAF, NRAS or EGFR gene mutation was detected in any type. Certain molecular-morphological correlations were demonstrated; however, no single or combined molecular alteration(s) was specific to any particular morphological type.

CONCLUSIONS

IBD-associated precancerous lesions are heterogeneous both histologically and molecularly. True colitis-associated adenomatous lesions are unlikely conventional adenomas. Non-adenomatous lesions without frank cytologic dysplasia should also be regarded as neoplastic.

Colorectal Serrated Polyp With Stromal Changes: An Interobserver Agreement Study

Background

Prolapse-related changes have been shown to be a confounding factor leading to misdiagnosis of serrated polyps in the rectum. Recent data on perineurial-like stromal proliferation in some sessile serrated polyps (SSPs) also highlights this issue.

Methods

Fifty-four consecutive serrated polyps with stromal changes from 42 patients were collected by one pathologist during a 2-month period (July and August of 2014). In addition, 20 cases of serrated polyps with perineurial-like stromal proliferation from 20 patients were retrieved from our pathology database from 2003 to 2010. The polyps were re-reviewed by three gastrointestinal pathologists for stromal changes, basal crypt distortion, and final classification into hyperplastic polyp (HP) or SSP. Final interpretation was correlated to clinicopathologic features and the presence of synchronous SSP and adenoma. In addition, the interobserver agreement on the stromal changes and basal crypt distortion in these polyps was determined.

Results

Upon histology review, all polyps showed stromal changes evident by at least one pathologist. Among the 74 polyps evaluated, a consensus diagnosis of HP and consensus diagnosis of SSP were reached in 39 and 11 polyps respectively. The overall interobserver agreement among three pathologists was moderate (kappa value 0.49, 95% confidence interval (CI) 0.32 - 0.66). A consensus diagnosis could not be reached in the remaining 24 polyps (32.4%). The SSPs were larger, were more often located in the right colon, and occurred more frequently in women when compared to HPs (7.3 ± 5.3 vs. 4.5 ± 2.7 mm, P = 0.019; 72.7% vs. 7.7%, P = 0.000014; and 77.7% vs. 30.7%, P = 0.019) but with comparable patient age (54.7 ± 10.6 years vs. 60.7 ± 11.4, P = 0.12). The SSPs were associated with higher risk of concurrent SSP in other parts of the colon (27.3% vs. 0%, P = 0.008) but not with the presence of concurrent adenoma (45.4% vs. 69.6%, P = 1). Among the 24 unclassifiable serrated polyps, 11 were interpreted by two reviewers as SSP and 13 interpreted by two reviewers as HP; the former group were more likely right-sided (45.4% vs. 15.4%, P = 0.046), but size of the polyps and age of the patients were comparable. Stromal changes (prolapse and perineurial-like) were agreed upon by all three pathologists in 33 (44.6%, of 74) polyps and these included 15 with prolapse changes and 18 perineurial-like stromal changes. Among those 15 with prolapse changes, 14 (93.3%) were agreed upon by three pathologists to be HP; in contrast, only four (22.2%, of 18) with perineurial-like stromal changes were diagnosed as HP by all three pathologists (P = 0.00008). Of 74 polyps, 16 were found to have basal crypt distortion involving more than one crypt and eight of them (50%) carried a final interpretation of SSP by all three pathologists and two (12.5%) HP.

Conclusions

Even though serrated polyps with stromal changes can be challenging, up to 67.7% of them could be readily classified as SSP or HP. The remaining unclassifiable serrated polyps with stromal changes may represent a heterogeneous group. Prolapse changes support the diagnosis of HP while basal crypt distortion in more than one crypt supports the diagnosis of SSP.

Inflammatory bowel disease- and Barrett's esophagus-associated neoplasia: the old, the new, and the persistent struggles

Early diagnosis of and adequate therapy for premalignant lesions in patients with inflammatory bowel disease (IBD) and Barrett's esophagus (BE) has been shown to decrease mortality. Endoscopic examination with histologic evaluation of random and targeted biopsies remains the gold standard for early detection and adequate treatment of neoplasia in both these diseases. Although eventual patient management (including surveillance and treatment) depends upon a precise histologic assessment of the initial biopsy, accurately diagnosing and grading IBD- and BE-associated dysplasia is still considered challenging by many general as well as subspecialized pathologists. Additionally, there are continuing updates in the literature regarding the diagnosis, surveillance, and treatment of these disease entities. This comprehensive review discusses the cancer risk, detailed histopathological features, diagnostic challenges, and updates as well as the latest surveillance and treatment recommendations in IBD- and BE-associated dysplasia.

Diagnostic Accuracy of Endoscopic Trimodal Imaging and Chromoendoscopy for Lesion Characterization in Ulcerative Colitis

BACKGROUND

During surveillance colonoscopy of patients with long-standing ulcerative colitis [UC], a variety of dysplastic and non-dysplastic lesions are detected. The aim of this study was to address the diagnostic accuracy of endoscopic characterization of endoscopic trimodal imaging [ETMI] and chromoendoscopy [CE]. ETMI includes the combination of autofluorescence imaging [AFI], narrow band imaging [NBI] and white light endoscopy [WLE].

METHODS

This is a pre-specified additional analysis of a multi-centre, randomized controlled trial that compared AFI with CE for dysplasia detection in 210 patients with long-standing UC [FIND-UC trial]. In the AFI arm, endoscopists used the ETMI system to record AFI colour, Kudo pit pattern using NBI and WLE for lesion characterization. For AFI, purple colour and ambiguous colour combined with pit pattern type III-V on NBI was considered dysplastic. Kudo pit pattern was described in the CE arm. For pit pattern description using NBI and CE, type III-V was considered dysplastic. Histology was the reference standard.

RESULTS

In total, 52 dysplastic and 255 non-dysplastic lesions were detected. Overall sensitivity for real-time prediction of dysplasia was 76.9% (95% confidence interval [CI] 46.2-95.0) for ETMI, and 81.6% [95% CI 65.7-92.3] for CE. Overall negative predictive value [NPV] for ETMI was 96.9% [95% CI 92.0-98.8] and 94.7% [90.2-97.2] for CE.

CONCLUSIONS

Sensitivity for endoscopic differentiation of dysplastic lesions detected during surveillance of patients with long-standing UC seems limited using ETMI and CE. Future research is warranted as the high NPV indicates that these techniques are valuable for the exclusion of dysplastic lesions [NTR4062].

Clinical, Histologic, and Immunophenotypic Features of Serrated Polyps in Patients With Inflammatory Bowel Disease

Background

Colorectal serrated polyps (SP), which include hyperplastic polyps (HP), sessile serrated adenomas/polyps (SSA/P), and traditional serrated adenomas, are not uncommon and have been implicated to play a role in the pathogenesis in a subset of sporadic colorectal carcinomas; however, their significance in patients with prolonged inflammatory bowel disease (IBD) remains unclear.

Methods

We retrospectively studied the clinicopathologic features, BRAF and β-catenin immunohistochemistry staining patterns in 36 SPs from 28 patients with IBD compared with 40 SPs in patients without IBD.

Results

Eleven SSA/Ps and 25 HPs from IBD and site-matched controls were included. SSA/Ps in the study group were slightly more commonly seen in males (55% vs. 41%, P = 0.7) and older patients (55.2 vs. 47.8 years, P = 0.2) compared to patients with HP. They were moderately larger (7.13 mm vs. 4.83 mm, P = 0.14) and more likely located on the right (63.6% vs. 32%, P = 0.46). Smaller percentage of SSA/Ps showed BRAF staining compared to controls (55.6% vs. 73.3%, P = 0.41) and HPs showed similar features (52.0% vs. 54.2%, P = 1). β-catenin was negative in all cases. During follow-up, only one patient in the SSA/P group developed carcinoma 42 months after at the same site and two developed adenoma-like low-grade dysplasia but no patients with HPs had such findings.

Conclusions

Our findings show that SPs in IBD share similar clinicodemographic and immunophenotypical features with sporadic SPs. However, patients with SSA/Ps may have a slight increase in risk of developing dysplasia compared to patients with HPs in IBD.

Chromoendoscopy versus autofluorescence imaging for neoplasia detection in patients with longstanding ulcerative colitis (FIND-UC): an international, multicentre, randomised controlled trial

BACKGROUND

Patients with longstanding ulcerative colitis undergo regular dysplasia surveillance because they have an increased colorectal cancer risk. Autofluorescence imaging and chromoendoscopy improve dysplasia detection. The aim of this study was to determine whether autofluorescence imaging should be further studied as an alternative method for dysplasia surveillance in patients with longstanding ulcerative colitis.

METHODS

This prospective, international, randomised controlled trial included patients from an ulcerative colitis-dysplasia surveillance cohort from five centres in the Netherlands and the UK. Eligible patients were aged 18 years or older who were undergoing dysplasia surveillance after being diagnosed with extensive colitis (Montreal E3) at least 8 years before study start or with left-sided colitis (Montreal E2) at least 15 years before study start. Randomisation (1:1) was minimised for a previous personal history of histologically proven dysplasia and concomitant primary sclerosing cholangitis. The coprimary outcomes were the proportion of patients in whom at least one dysplastic lesion was detected and the mean number of dysplastic lesions per patient. The relative dysplasia detection rate, calculated as the ratio of the detection rates by autofluorescence imaging and chromoendoscopy, needed to be more than 0·67 (using an 80% CI) for both primary outcomes to support a subsequent large non-inferiority trial. Outcomes were analysed on a per-protocol basis. The trial is registered at the Netherlands Trial Register, number NTR4062.

FINDINGS

Between Aug 1, 2013, and March 10, 2017, 210 patients undergoing colonoscopy surveillance for longstanding ulcerative colitis were randomised for inspection with either autofluorescence imaging (n=105) or chromoendoscopy (n=105). Dysplasia was detected in 13 (12%) patients by autofluorescence imaging and in 20 patients (19%) by chromoendoscopy. The relative dysplasia detection rate of autofluorescence imaging versus chromoendoscopy for the proportion of patients with ulcerative colitis with at least one dysplastic lesion was 0·65 (80% CI 0·43-0·99). The mean number of detected dysplastic lesions per patient was 0·13 (SD 0·37) for autofluorescence imaging and 0·37 (1·02) for chromoendoscopy (relative dysplasia detection rate 0·36, 80% CI 0·21-0·61). Adverse events were reported for two patients in the autofluorescence imaging group (one patient had intraprocedural mild bleeding, and one patient had abdominal pain) and for three patients in the chromoendoscopy group (two patients had intraprocedural mild bleeding, and one patient had perforation).

INTERPRETATION

Autofluorescence imaging did not meet criteria for proceeding to a large non-inferiority trial. Therefore, existing autofluorescence imaging technology should not be further investigated as an alternative dysplasia surveillance method.

FUNDING

Olympus Europe and Olympus Keymed.