Gut-associated lymphoid tissue attrition associates with response to anti-α4ß7 therapy in ulcerative colitis.

Vedolizumab (VDZ) is a first-line treatment in ulcerative colitis (UC) that targets the α4ß7- mucosal vascular addressin cell adhesion molecule 1 (MAdCAM-1) axis. To determine the mechanisms of action of VDZ, we examined five distinct cohorts of patients with UC. A decrease in naïve B and T cells in the intestines and gut-homing (ß7+) plasmablasts in circulation of VDZ-treated patients suggested that VDZ targets gut-associated lymphoid tissue (GALT). Anti-α4ß7 blockade in wild-type and photoconvertible (KikGR) mice confirmed a loss of GALT size and cellularity because of impaired cellular entry. In VDZ-treated patients with UC, treatment responders demonstrated reduced intestinal lymphoid aggregate size and follicle organization and a reduction of ß7+IgG+ plasmablasts in circulation, as well as IgG+ plasma cells and FcγR-dependent signaling in the intestine. GALT targeting represents a previously unappreciated mechanism of action of α4ß7-targeted therapies, with major implications for this therapeutic paradigm in UC.

Clinicopathologic comparison between sporadic and syndromic Peutz-Jeghers polyps.

Peutz-Jeghers polyps (PJPs) are hamartomatous polyps that may define patients with Peutz-Jeghers syndrome (PJS), a rare inherited polyposis syndrome with high cancer risk. However, the clinical significance of 1-2 sporadic PJPs (without other PJS stigmata) regarding malignant potential and identification of new PJS probands is still unclear. We identified 112 patients with 524 histologically confirmed PJPs and categorized them based on polyp number into syndromic (n = 38) if ≥3 PJPs or diagnosed PJS, solitary (1 PJP, n = 61), and intermediate (2 PJPs, n = 13). Clinicopathologic features, including presence of dysplasia in the polyp and development of neoplasia in the patient, were compared on a per-patient and per-polyp basis. Whereas patients with solitary and intermediate PJPs were not different from each other, patients with syndromic PJPs were, in multivariate analysis, younger (P = .001) and more likely to develop neoplasia (P = .02) over a 62.6-months median follow-up than patients with sporadic PJPs. On an individual polyp basis, syndromic PJPs were more likely, in multivariate analysis, to occur in the small intestine (P < .001), but less likely to harbor metaplasia (P = .03) or dysplasia (P = .001), than sporadic PJPs. Dysplasia and metaplasia were more likely in larger PJPs, by multivariate analysis (P = .007 and P < .001, respectively). These data suggest that strict criteria for PJS (including ≥3 PJPs), as currently used, stratify patients into distinct groups with significant differences in clinicopathologic parameters, particularly regarding risk of neoplasia. However, sporadic PJPs exhibit characteristics such as dysplasia and are thus important to recognize and diagnose but perhaps as heralding only a forme fruste PJS.

Debating Deposits, Redux: Substantial Interobserver Agreement Exists in Distinguishing Tumor Deposits From Nodal Metastases in Small Bowel Neuroendocrine Tumors.

CONTEXT.­: Recent data suggest mesenteric tumor deposits (MTDs) indicate poor prognosis in small bowel well-differentiated neuroendocrine tumors (SB-NETs), including compared to positive lymph nodes, making their distinction crucial. OBJECTIVE.­: To study interobserver agreement in distinguishing SB-NET MTDs from positive nodes. DESIGN.­: Virtual slides from 36 locally metastatic SB-NET foci were shared among 7 gastrointestinal pathologists, who interpreted each as an MTD or a positive node. Observers ranked their 5 preferred choices among a supplied list of potentially useful histologic features, for both options. Diagnostic opinions were compared using Fleiss multirater and Cohen weighted κ analyses. RESULTS.­: Preferred criteria for MTD included irregular shape (n = 7, top choice for 5), perineural invasion/nerve entrapment (n = 7, top choice for 2), encased thick-walled vessels (n = 7), and prominent fibrosis (n = 6). Preferred criteria for positive nodes included peripheral lymphoid follicles (n = 6, top choice for 4), round shape (n = 7, top choice for 2), peripheral lymphocyte rim (n = 7, top choice for 1), subcapsular sinuses (n = 7), and a capsule (n = 6). Among 36 foci, 10 (28%) each were unanimously diagnosed as MTD or positive node. For 13 foci (36%), there was a diagnosis favored by most observers (5 or 6 of 7): positive node in 8, MTD in 5. Only 3 cases (8%) had a near-even (4:3) split. Overall agreement was substantial (κ = .64, P < .001). CONCLUSIONS.­: Substantial interobserver agreement exists for distinguishing SB-NET MTDs from lymph node metastases. Favored histologic criteria in making the distinction include irregular shape and nerve/vessel entrapment for MTD, and peripheral lymphocytes/lymphoid follicles and round shape for positive nodes.

Prognostic Factors Among Colonic Adenocarcinomas Invading Into the Muscularis Propria.

Depth of invasion through the intestinal wall, categorized as primary tumor stage (pT), is an important prognostic factor in colorectal cancer. However, additional variables that may affect clinical behavior among tumors involving the muscularis propria (pT2) have not been examined at length. We evaluated 109 patients with pT2 colonic adenocarcinomas (median age: 71 y, interquartile range: 59 to 79 y) along various clinicopathologic parameters, including invasion depth, regional lymph node involvement, and disease progression after resection. Tumors extending to the outer muscularis propria (termed pT2b) were associated in multivariate analysis with older patient age ( P =0.04), larger tumor size ( P <0.001), higher likelihood of lymphovascular invasion (LVI; P =0.03) and higher lymph node stage (pN; P =0.04), compared with tumors limited to the inner muscle layer (pT2a), and LVI was the single most important variable predicting regional lymph node metastasis at resection in these tumors ( P =0.001). The Kaplan-Meier analysis during a median clinical follow-up of 59.7 months (interquartile range: 31.5 to 91.2) revealed that disease progression was more likely in pT2 tumors that exhibited, at the time of staging: size >2.5 cm ( P =0.039), perineural invasion (PNI; P =0.047), high-grade tumor budding ( P =0.036), higher pN stage ( P =0.002), and distant metastasis ( P <0.001). Proportional hazards (Cox) regression identified high-grade tumor budding ( P =0.02) as independently predicting shorter progression-free survival in pT2 tumors. Finally, among cases that would not ordinarily be candidates for adjuvant treatment (ie, pT2N0M0), the presence of high-grade tumor budding was significantly associated with disease progression ( P =0.04). These data suggest that, during the diagnosis of pT2 tumors, pathologists may wish to pay particular attention and ensure adequate reporting of certain variables such as tumor size, depth of invasion within the muscularis propria (ie, pT2a vs. pT2b), LVI, PNI, and, especially, tumor budding, as these may affect clinical treatment decisions and proper patient prognostication.

Myeloid cell influx into the colonic epithelium is associated with disease severity and non-response to anti-Tumor Necrosis Factor Therapy in patients with Ulcerative Colitis.

Ulcerative colitis (UC) is an idiopathic chronic inflammatory disease of the colon with sharply rising global prevalence. Dysfunctional epithelial compartment (EC) dynamics are implicated in UC pathogenesis although EC-specific studies are sparse. Applying orthogonal high-dimensional EC profiling to a Primary Cohort (PC; n=222), we detail major epithelial and immune cell perturbations in active UC. Prominently, reduced frequencies of mature BEST4+OTOP2+ absorptive and BEST2+WFDC2+ secretory epithelial enterocytes were associated with the replacement of homeostatic, resident TRDC+KLRD1+HOPX+ γδ+ T cells with RORA+CCL20+S100A4+ TH17 cells and the influx of inflammatory myeloid cells. The EC transcriptome (exemplified by S100A8, HIF1A, TREM1, CXCR1) correlated with clinical, endoscopic, and histological severity of UC in an independent validation cohort (n=649). Furthermore, therapeutic relevance of the observed cellular and transcriptomic changes was investigated in 3 additional published UC cohorts (n=23, 48 and 204 respectively) to reveal that non-response to anti-Tumor Necrosis Factor (anti-TNF) therapy was associated with EC related myeloid cell perturbations. Altogether, these data provide high resolution mapping of the EC to facilitate therapeutic decision-making and personalization of therapy in patients with UC.

Gut-associated lymphoid tissue attrition associates with response to anti-α4ß7 therapy in ulcerative colitis.

Targeting the α4ß7-MAdCAM-1 axis with vedolizumab (VDZ) is a front-line therapeutic paradigm in ulcerative colitis (UC). However, mechanism(s) of action (MOA) of VDZ remain relatively undefined. Here, we examined three distinct cohorts of patients with UC (n=83, n=60, and n=21), to determine the effect of VDZ on the mucosal and peripheral immune system. Transcriptomic studies with protein level validation were used to study drug MOA using conventional and transgenic murine models. We found a significant decrease in colonic and ileal naïve B and T cells and circulating gut-homing plasmablasts (ß7+) in VDZ-treated patients, pointing to gut-associated lymphoid tissue (GALT) targeting by VDZ. Murine Peyer's patches (PP) demonstrated a significant loss cellularity associated with reduction in follicular B cells, including a unique population of epithelium-associated B cells, following anti-α4ß7 antibody (mAb) administration. Photoconvertible (KikGR) mice unequivocally demonstrated impaired cellular entry into PPs in anti-α4ß7 mAb treated mice. In VDZ-treated, but not anti-tumor necrosis factor-treated UC patients, lymphoid aggregate size was significantly reduced in treatment responders compared to non-responders, with an independent validation cohort further confirming these data. GALT targeting represents a novel MOA of α4ß7-targeted therapies, with major implications for this therapeutic paradigm in UC, and for the development of new therapeutic strategies.

Further prognostic stratification of intestinal type of gastric adenocarcinoma by CDX2 expression pattern.

Gastric cancer is one of the most deadly malignancies worldwide. It is routinely divided into 2 common histologic subtypes by the Lauren classification, intestinal type and diffuse type. In recent years, the intestinal type of gastric cancer has been found to represent a heterogeneous disease with divergent prognosis. Our objective was to investigate the CDX2/CK7 immunohistochemical pattern and its role in further stratifying this type of gastric cancer. Gastrectomy cases with a diagnosis of the intestinal type of gastric adenocarcinoma from a single large institution between 2008 and 2022 were collected. Forty-four cases with available blocks and enough tumor tissue were included in this study. Four different immunohistochemical patterns were identified: CDX2+/CK7+ (40.9%), CDX2-/CK7+ (34.1%), CDX2+/CK7- (18.2%), and CDX2-/CK7- (6.8%). Compared to CDX2-negative cases, CDX2-positive ones are more likely to present better prognostic histopathological features including early stage, less perineural and lymphovascular invasion, and lower nodal metastasis. In addition, CDX2 expression was associated with specific molecular features like HER2 overexpression and genetic alterations of receptor tyrosine kinase (TRK) genes including EGFR, ERBB2, ERBB3, DDR2, and MET. In conclusion, according to the CDX2 expression pattern, the intestinal type of gastric cancer could be further divided into 2 subgroups, which have different histopathological and molecular features and different prognosis.

Aberrant p53 expression is associated with neoplastic progression in Barrett oesophagus diagnosed as indefinite for dysplasia.

The aim of this study was to investigate the role of immunohistochemical (IHC) expression of p53 and other potential clinical parameters as prognostic markers for predicting neoplastic progression in Barrett oesophagus (BE) patients diagnosed as indefinite for dysplasia (IND). The study included patients with established BE of any extent who had a diagnosis of IND accompanied by concurrent p53 immunohistochemistry (IHC) stain at the index endoscopic procedure and at least one follow-up examination between 2000 and 2021. Correlation between disease progression from IND to higher-grade dysplasia [low-grade dysplasia (LGD), high-grade dysplasia (HGD) and oesophageal adenocarcinoma (EAC)] and clinicopathological parameters were analysed. A total of 149 patients (99 males; mean age 63.3 ± 10.0 years, range = 35-89) were included in the final analysis. Median follow-up was 37.1 months [interquartile range (IQR) = 20.5-59.1 months]. Progression rates from IND to LGD and HGD were 12.1% (18 of 149) and 2.7% (four of 149), respectively. On multivariate analysis, the number of IND diagnoses was significantly associated with progression to both LGD and HGD (P = 0.016 and P < 0.001, respectively). Cox regression analysis showed that aberrant p53 expression was significantly associated with progression to LGD [hazard ratio (HR) = 4.87, 95% confidence interval (CI) = 1.91-12.45, P = 0.001] and HGD (HR = 21.81, 95% CI = 1.88-253.70, P = 0.014). Kaplan-Meier survival analysis also demonstrated that aberrant p53 expression was significantly associated with progression to LGD (P < 0.001) and HGD (P = 0.001). Our results suggest that frequency of IND diagnoses and status of p53 expression can help to stratify risk of neoplastic progression in BE patients with IND.

Clinicopathologic parameters and outcomes of mucinous neoplasms confined to the appendix: a benign entity with excellent prognosis.

Appendiceal mucinous neoplasms (AMNs), characterized by expansile or "pushing" growth of neoplastic epithelium through the appendix wall, are sometimes accompanied by peritoneal involvement, the extent and grade of which largely determine clinical presentation and long-term outcomes. However, the prognosis of tumors entirely confined to the appendix is still debated and confusion remains regarding their biologic behavior and, consequently, their clinical management and even diagnostic nomenclature. We evaluated AMNs limited to the appendix from 337 patients (median age: 58 years, interquartile range (IQR): 47-67), 194 (57.6%) of whom were women and 143 (42.4%) men. The most common clinical indication for surgery was mass or mucocele, in 163 (48.4%) cases. Most cases (N = 322, 95.5%) comprised low-grade epithelium, but there were also 15 (4.5%) cases with high-grade dysplasia. Lymph nodes had been harvested in 102 (30.3%) cases with a median 6.5 lymph nodes (IQR: 2-14) per specimen for a total of 910 lymph nodes examined, all of which were negative for metastatic disease. Histologic slide review in 279 cases revealed 77 (27.6%) tumors extending to the mucosa, 101 (36.2%) to submucosa, 33 (11.8%) to muscularis propria, and 68 (24.4%) to subserosal tissues. In multivariate analysis, deeper tumor extension was associated with older age (p = 0.032; odds ratio (OR): 1.02, 95% confidence intervals (CI): 1.00-1.03), indication of mass/mucocele (p < 0.001; OR: 2.09, CI: 1.41-3.11), and wider appendiceal diameter, grossly (p < 0.001; OR: 1.61, CI: 1.28-2.02). Importantly, among 194 cases with at least 6 months of follow-up (median: 56.1 months, IQR: 24.4-98.5), including 9 high-grade, there was no disease recurrence/progression, peritoneal involvement (pseudomyxoma peritonei), or disease-specific mortality. These data reinforce the conclusion that AMNs confined to the appendix are characterized by benign biologic behavior and excellent clinical prognosis and accordingly suggest that revisions to their nomenclature and staging would be appropriate, including reverting to the diagnostic term mucinous adenoma in order to accurately describe a subset of them.

Characteristics and Outcomes of Left-sided Ulcerative Colitis With a Cecal/Periappendiceal Patch of Inflammation.

Ulcerative colitis (UC) is characterized by continuous mucosal inflammation of the rectum, extending uninterrupted to a variable portion of the colon proximally. However, in some patients with distal colitis, a distinct pattern of skip inflammation (so-called patch) involves the cecum and/or appendiceal orifice, but data on this entity are contradictory, and its significance and prognosis are still debated. We identified 102 adult cases of left-sided UC with a cecal/periappendiceal patch and compared them to 102 controls (left-sided UC only) along clinicopathologic characteristics and disease outcomes. In multivariate analysis, patients with a patch were younger (median age: 31 vs. 41 y; P =0.004) and more likely to have rectosigmoid involvement only (58.8% vs. 28.4%; P <0.001), compared with patients without a patch. During follow-up, patients with a patch were more likely to be eventually diagnosed with Crohn disease (CD) (9.8% vs. 1.0%; P =0.022) and to show proximal extension of inflammation (35.6% vs. 10.0%; P =0.021), but showed no differences in rates of neoplasia, colectomy, or pharmacotherapy escalation. Kaplan-Meier analysis confirmed that patients with a biopsy diagnosis of cecal/periappendiceal patch were more likely to show proximal disease extension ( P <0.001) and to be diagnosed with CD ( P =0.008). In conclusion, cecal/periappendiceal skip inflammation in left-sided UC occurs more often in younger patients and in those with rectosigmoid involvement and is associated with proximal disease extension and, in a small fraction of cases, change of diagnosis to CD. However, it does not portend increased risk of neoplasia, pharmacotherapy escalation, or subsequent colectomy, compared with patients with left-sided UC only.

Surgery for pouch inflow limb-related complications: Crohn's disease or something else?

PURPOSE: A total proctocolectomy with subsequent creation of an ileal-pouch, such as a J-pouch or a Kock pouch, has been the most common surgery performed for ulcerative colitis (UC). A small portion of these patients will develop complications with the inflow limb into the pouch requiring operative intervention. The objective was to establish a better understanding as to the pathological mechanism by which these pouch inflow limb problems develop. METHODS: This was a retrospective cohort study conducted at a single tertiary care inflammatory bowel disease (IBD) center. A database was created of all the patients who underwent pouch-related procedures, following completion of their original pouch, between 2006 and 2018. The patients requiring operative resection for inflow limb complications were identified among this cohort. Operative and pathological data were collected. RESULTS: One hundred seventy-eight UC patients underwent surgeries on their pouches between 2006 and 2018. Sixteen patients required operative resection for inflow limb problems. Reoperations for inflow limb problems included inflow limb resection with pouch excision (n = 4) and inflow limb resection with pouch revision (n = 12). The pathology findings of the inflow limb were consistent with Crohn's disease in 9 patients (56%). Two other patients (total 69%) were eventually diagnosed with Crohn's disease due to other pathological specimens or perianal pathology. The remaining patients had chronic, non-specific enteritis/serositis. CONCLUSIONS: A small proportion of pouch patients will eventually require surgery for inflow limb complications. Among these, there was a high rate of Crohn's disease of the inflow limb and overall change in diagnosis to Crohn's disease (Plietz et al. in Official Journal of the American College of Gastroenterology | ACG 114:S453, 2019).

Evaluation of Pathologic Prognostic Factors in Neuroendocrine Tumors of the Small Intestine.

The precise contributions of histopathologic features in the determination of stage and prognosis in small intestinal neuroendocrine tumors (NETs) are still under debate, particularly as they pertain to primary tumor size, mesenteric tumor deposits (TDs), and number of regional lymph nodes with metastatic disease. This single-institution series reviewed 162 patients with small bowel NETs (84 females, mean age: 60.3±12.0 y). All cases examined (100%) were immunoreactive for both chromogranin A and synaptophysin. Primary tumor size >1 cm (P=0.048; odds ratio [OR]=3.06, 95% confidence interval [CI]: 1.01-9.24) and lymphovascular invasion (P=0.007; OR=4.85, 95% CI: 1.53-15.40) were associated with the presence of lymph node metastasis. Conversely, TDs (P=0.041; OR=2.73, 95% CI: 1.04-7.17) and higher pT stage (P=0.006; OR=4.33, 95% CI: 1.53-12.28) were associated with the presence of distant metastasis (pM). A cutoff of ≥7 positive lymph nodes was associated with pM (P=0.041), and a thusly defined modified pN stage (pNmod) significantly predicted pM (P=0.024), compared with the prototypical pN (cutoff of ≥12 positive lymph nodes), which did not. Over a median follow-up of 35.7 months, higher pNmod (P=0.014; OR=2.15, 95% CI: 1.16-3.96) and pM (P<0.001; OR=11.00, 95% CI: 4.14-29.20) were associated with disease progression. Proportional hazards regression showed that higher pNmod (P=0.020; hazard ratio=1.51, 95% CI: 1.07-2.15) and pM (P<0.001; hazard ratio=5.48, 95% CI: 2.90-10.37) were associated with worse progression-free survival. Finally, Kaplan-Meier survival analysis demonstrated that higher pNmod (P=0.003), pM (P<0.001), and overall stage group (P<0.001) were associated with worse progression-free survival, while higher pM also predicted worse disease-specific survival (P=0.025). These data support requiring either chromogranin or synaptophysin, but not both, for small bowel NET diagnosis, the current inclusion of a 1 cm cutoff in primary tumor size and the presence of TDs in staging guidelines, and would further suggest lowering the cutoff number of positive lymph nodes qualifying for pN2 to 7 (from 12).

An accessible, efficient, and accurate natural language processing method for extracting diagnostic data from pathology reports.

Context: Analysis of diagnostic information in pathology reports for the purposes of clinical or translational research and quality assessment/control often requires manual data extraction, which can be laborious, time-consuming, and subject to mistakes. Objective: We sought to develop, employ, and evaluate a simple, dictionary- and rule-based natural language processing (NLP) algorithm for generating searchable information on various types of parameters from diverse surgical pathology reports. Design: Data were exported from the pathology laboratory information system (LIS) into extensible markup language (XML) documents, which were parsed by NLP-based Python code into desired data points and delivered to Excel spreadsheets. Accuracy and efficiency were compared to a manual data extraction method with concordance measured by Cohen's κ coefficient and corresponding P values. Results: The automated method was highly concordant (90%-100%, P<.001) with excellent inter-observer reliability (Cohen's κ: 0.86-1.0) compared to the manual method in 3 clinicopathological research scenarios, including squamous dysplasia presence and grade in anal biopsies, epithelial dysplasia grade and location in colonoscopic surveillance biopsies, and adenocarcinoma grade and amount in prostate core biopsies. Significantly, the automated method was 24-39 times faster and inherently contained links for each diagnosis to additional variables such as patient age, location, etc., which would require additional manual processing time. Conclusions: A simple, flexible, and scaleable NLP-based platform can be used to correctly, safely, and quickly extract and deliver linked data from pathology reports into searchable spreadsheets for clinical and research purposes.

Clinicopathologic Characteristics and Neoplasia Risk of Colorectal Inflammatory Polyposis in Inflammatory Bowel Disease.

CONTEXT.­: Inflammatory polyps (IPs) in inflammatory bowel disease may have been associated in the past with increased neoplasia risk. Additionally, colonic mucosa in filiform polyposis and giant inflammatory polyposis may be difficult to visualize during endoscopic surveillance, perhaps contributing to early colectomy in these patients. OBJECTIVE.­: To examine the clinicopathologic characteristics and significance of IPs and inflammatory polyposis in inflammatory bowel disease. DESIGN.­: We identified 336 resections from inflammatory bowel disease patients (212 [63.1%] male; mean age, 40.3 years; 175 [52.1%] with ulcerative colitis), including 78 with rare/few (<10) IPs, 141 with multiple (≥10) IPs, and 117 with inflammatory polyposis (including 30 with filiform polyposis/giant inflammatory polyposis) and compared them with 100 controls without IPs along various parameters, including overall and occult (unexpected) dysplasia. RESULTS.­: There was no increased neoplasia in resections with IPs compared with controls, given similar age, disease duration, degree of inflammation, anatomical extent of colitis, prevalence of primary sclerosing cholangitis, and tissue sampling. Increasing numbers of IPs and inflammatory polyposis were significantly associated in multivariate analysis with ulcerative and indeterminate colitis (P = .003) and shorter disease duration (P = .01), but also, and independently, with lower rates of dysplasia overall, including all grades (P = .001) and advanced neoplasia (P = .04). There were no instances of occult dysplasia (any grade) among inflammatory polyposis cases. CONCLUSIONS.­: These findings support the conclusion that the presence of IPs per se, and inflammatory polyposis in particular (including filiform polyposis and giant inflammatory polyposis), should not be considered an independent risk factor for the development of neoplasia in inflammatory bowel disease patients, outside the context of disease duration and inflammatory burden.

Pathology and Prognosis of Colonic Adenocarcinomas With Intermediate Primary Tumor Stage Between pT2 and pT3.

CONTEXT.­: Primary tumor stage (pT) is an important prognostic indicator in colonic adenocarcinomas; however, cases that have no muscle fibers beyond the advancing tumor edge but also show no extension beyond the apparent outer border of the muscularis propria (termed pT2int) have not been previously studied. OBJECTIVE.­: To address the clinicopathologic characteristics and prognosis of pT2int tumors. DESIGN.­: We recharacterized 168 colon carcinomas and compared pT2int cases to bona fide pT2 and pT3 tumors. RESULTS.­: In side-by-side analysis, 21 pT2int cases diverged from 29 pT2 tumors only in terms of larger size (P = .03), but they were less likely to show high-grade (P = .03), lymphovascular (P < .001), and extramural venous invasion (P = .04); discontinuous tumor deposits (P = .02); lymph node involvement (P = .001); and advanced stage (P = .001) compared with 118 pT3 tumors. Combining pT2int with pT2 cases (versus pT3) was a better independent predictor of negative lymph nodes in multivariate analysis (P = .04; odds ratio [OR], 3.96; CI, 1.09-14.42) and absent distant metastasis in univariate analysis (P = .04) compared with sorting pT2int with pT3 cases (versus pT2). Proportional hazards regression showed that pT2 and pT2int cases together were associated with better disease-free survival compared with pT3 tumors (P = .04; OR, 3.65; CI, 1.05-12.70). Kaplan-Meier analysis demonstrated that when pT2int were grouped with pT2 tumors, they were significantly less likely to show disease progression compared with pT3 (P = .002; log-rank test) and showed a trend toward better disease-specific survival (P = .06) during a mean patient follow-up of 44.9 months. CONCLUSIONS.­: These data support the conclusion that pT2int carcinomas have clinicopathologic characteristics and are associated with patient outcomes more closely aligned with pT2 rather than pT3 tumors.

Impact of COVID-19 pandemic on gastrointestinal cancer diagnosis and resection: An observational study.

BACKGROUND: The COVID-19 pandemic disrupted routine screening for and treatment of gastrointestinal (GI) cancers. We analyzed changes in GI cancer pathology specimens resulting from diagnostic and therapeutic procedures at a single academic center in an epicenter of the COVID-19 pandemic. Our aim was to determine which cancer types, procedures, and patients were impacted by the pandemic. METHODS: This was a retrospective, cohort study of patients identified based on carcinoma containing pathologic specimens reviewed in our institution resulting from diagnostic or resection procedures. Pathology and medical records of patients with GI and liver carcinoma and high-grade dysplasia were reviewed from February 1 to April 30 in 2018, 2019 and 2020. We used March 16, 2020 to delineate the pre-COVID-19 and COVID-19 period in 2020. Chi-squared or t-tests, as appropriate, were used to compare these time periods in each year. Mann Kendall test was used to test for trend in volume. ANCOVA was used to compare differences across years. RESULTS: A total of 1028 pathology samples from 949 unique patients were identified during the study period. There was a 57% drop in samples within 2020 (p = 0.01) that was not present in either 2018 or 2019 (p<0.01). In 2020, there were significantly fewer resections compared to biopsies overall in the COVID-19 period (p = 0.01). There were fewer colorectal cancer specimens (p = 0.04) which were procured from older patients (p<0.01) in the 2020 COVID-19 period compared to pre-COVID-19. CONCLUSIONS: In our institution, there was a significant drop in diagnostic and resection specimens of GI cancers during the COVID-19 pandemic, disproportionately affecting older colorectal cancer patients.

Outcomes of Remote Pathology Instruction in Student Performance and Course Evaluation.

The coronavirus disease 2019 (COVID-19) pandemic has disrupted undergraduate medical education, including preclinical class-based courses, by requiring social distancing and essentially eliminating in-person teaching. The aim of this study was to compare student performance and satisfaction before and after implementation of remote instruction in a first-year introductory pathology course. Assessments (3 quizzes, 1 practical exam, and 1 final) were compared between courses given before (January 2020) and during (January 2021) the COVID-19 pandemic, in terms of mean scores, degree of difficulty, and item discrimination, both overall and across different question types. Students' evaluations of the course (Likert scale-based) were also compared between the 2 years. Significantly higher mean scores were observed during remote instruction (compared to the prior, in-person year) on verbatim-repeated questions (94.9 ± 8.8 vs 89.4 ± 12.2; P = .002) and on questions incorporating a gross specimen image (88.4 ± 7.5 vs 84.4 ± 10.3; P = .007). The percentage of questions that were determined to be moderate/hard in degree of difficulty and good/very good in item discrimination remained similar between the 2 time periods. In the practical examination, students performed significantly better during remote instruction on questions without specimen images (96.5 ± 7.0 vs 91.2 ± 15.2; P = .004). Finally, course evaluation metrics improved, with students giving a higher mean rating value in each measured end point of course quality during the year of remote instruction. In conclusion, student performance and course satisfaction generally improved with remote instruction, suggesting that the changes implemented, and their consequences, should perhaps inform future curriculum improvements.

Clinicopathological characteristics and aetiological factors of granulomatous gastritis.

AIMS: To examine the clinicopathological characteristics of granulomatous gastritis (GG) among different aetiologies, particularly Crohn disease (CD), and determine the contribution of Helicobacter pylori and the clinical significance of isolated GG. METHODS AND RESULTS: We identified 269 GG cases overall (0.19% prevalence): 220 had an underlying granulomatous disease (CD, sarcoidosis, tuberculosis) and only eight of these (3.6%) had H. pylori, fewer than the 10.3% rate among non-GG biopsies (P < 0.001). Conversely, among 49 GG cases without known cause (foreign body, undetermined, idiopathic), 13 (26.5%) had H. pylori more than background (P = 0.001). Most patients (n = 185/68.8%) had CD and these were more probably male (P < 0.001), younger (P < 0.001), white (P < 0.001) and had single (P = 0.010), smaller (P = 0.005) and antral (P = 0.027) granulomas amid inflammation (P = 0.005) compared to non-CD GG cases; younger age was independently associated with CD [P = 0.003; odds ratio (OR) = 1.13, 95% confidence interval (CI) = 1.04-1.22]. Among CD patients, younger age (P = 0.003; OR = 1.04, 95% CI = 1.01-1.07) and upper gastrointestinal (GI) symptoms (P = 0.017; OR = 2.53, 95% CI = 1.18-5.43) were associated with new (versus established) diagnosis, whereas multiple gastric granulomas (P = 0.003; OR = 4.67, 95% CI = 1.67-13.04) and lack of upper GI symptoms (P < 0.001; OR = 6.75, 95% CI = 2.94-15.49) were associated with lower GI granulomas. Of 86 isolated GG cases (i.e. no prior diagnosis or lower GI granulomas), 51 (59.3%) were eventually diagnosed with CD, and this was independently associated with younger age (P = 0.014; OR = 1.11, 95% CI = 1.02-1.21) and upper GI symptoms (P = 0.033; OR = 19.27, 95% CI = 1.27-293.31). The positive predictive value of finding isolated GG towards a CD diagnosis in patients aged <30 years was 91%, increasing in males (93%), with single (94%), antral (97%) granulomas or upper GI symptoms (94%). CONCLUSIONS: GG does not correlate with H. pylori in patients with granulomatous disease, but may be associated with the organism when such diagnosis is lacking. In CD patients with GG, younger age and upper GI symptoms are associated with a new CD diagnosis, whereas multiple gastric granulomas and lack of upper GI symptoms correlate with lower GI granulomas. GG, including in isolated cases with no prior clinical history or granuloma, probably signifies CD, particularly in younger, male patients or those with single, antral granulomas or upper GI symptoms.

Impact of pathological response after neoadjuvant chemotherapy on adjuvant therapy decisions and patient outcomes in gastrointestinal cancers.

BACKGROUND: Neoadjuvant chemotherapy (NAC) is frequently used in gastrointestinal cancers (GIC), and pathological, radiological, and tumor marker responses are assessed during and after NAC. AIM: To evaluate the relationship between pathologic, radiologic, tumor marker responses and recurrence-free survival (RFS), overall survival (OS), adjuvant chemotherapy (AC) decisions, and the impact of changing to a different AC regimen after poor response to NAC. METHODS AND RESULTS: Medical records of GIC patients treated with NAC at Mount Sinai between 1/2012 and 12/2018 were reviewed. One hundred fifty-six patients (58.3% male, mean age 63 years) were identified. Primary tumor sites were: 43 (27.7%) pancreas, 62 (39.7%) gastroesophageal, and 51 (32.7%) colorectal. After NAC, 31 (19.9%) patients had favorable pathologic response (FPR; defined as College of American Pathologists [CAP] score 0-1). Of 107 patients with radiological data, 59 (55.1%) had an objective response, and of 113 patients with tumor marker data, 61 (54.0%) had a ≥50% reduction post NAC. FPR, but not radiographic or serological responses, was associated with improved RFS (HR 0.28; 95% CI 0.11-0.72) and OS (HR 0.13; 95% CI 0.2-0.94). Changing to a different AC regimen from initial NAC, among all patients and specifically among those with unfavorable pathological response (UPR; defined as CAP score 2-3) after NAC, was not associated with improved RFS or OS. CONCLUSIONS: GIC patients with FPR after NAC experienced significant improvements in RFS and OS. Patients with UPR did not benefit from changing AC. Prospective studies to better understand the role of pathological response in AC decisions and outcomes in GIC patients are needed.