Pyloric gland metaplasia: Potential histologic predictor of severe pouch disease including Crohn's disease of the pouch in ulcerative colitis.

Crohn's disease of the pouch (CDP) is seen in a subset of ulcerative colitis (UC) patients following ileal pouch-anal anastomosis (IPAA). Histologic or clinical predictors of CDP are unknown. UC patients with subsequent CDP diagnosis were identified. The rationales for the diagnosis, the interval from the initial signs of CDP to the diagnosis, family history and smoking history were reviewed. Archived pathology materials were reviewed for the presence of pyloric gland metaplasia (PGM) and compared with those from UC with similar severity of pouchitis with CDP (matched UC controls), random UC controls, and ileocolectomies from primary CD patients. CDP diagnosis was made in 26 (18.1%) of 144 patients; all of them met commonly used diagnostic criteria for CDP. The diagnosis was rendered on average 15 months after the initial CD-like signs. PGM was found in 58% of CDP, more common than random UC controls but no different from primary CD and matched UC controls. PGM preceded first signs of CD in a subset. Patients with a family history of CD were more likely to develop CDP than those without a family history of any type of inflammatory bowel disease. Smoking status did not affect the likelihood of developing CDP. Finding PGM in proctocolectomy, ileostomy and follow-up biopsies in UC patients post IPAA may warrant close follow up for the potential development of pouchitis. Some of these patients, especially those with family history of CD, may further progress and develop severe disease meeting the clinical diagnostic criteria for CDP.

Lymphocytic colitis pattern of injury presenting as endoscopic polyps: a case series.

Lymphocytic colitis (LC) is characterized by chronic watery diarrhea and unremarkable endoscopic findings. Only one case of LC presenting as multiple colonic polyps has been reported. We report a case series of histologic LC pattern of injury (LCPI), presenting as endoscopic polyps, and compare them with typical LC cases. Eighteen archived (2009-2019) polypoid LCPI cases without an associated cause of polyp, such as adenoma, hyperplastic change, or lymphoid aggregate, were retrieved from 17 (12 female and 5 male) patients. The clinical history and endoscopic findings were noted. A total of 40 conventional LC cases were used as controls. Fisher's exact test was performed to evaluate associations between two variables. The mean age of the patients was 61.1 years. The indication for colonoscopy was chronic watery diarrhea (56%), screening/surveillance (33%), and rectal bleeding (11%). The mean number and size of the polyps was 1.6 and 2.9 mm, respectively. Seventy-six percent were located in the left colon, and 48% were sessile. When biopsied (14/18; 78%), the background colonic mucosa showed LCPI. There was no significant difference in age, gender, and the average number of lymphocytes in the two groups. Hypertension and history of malignancy was more common in the polypoid LCPI group than in the control LC group (P < 0.05). LCPI may present as endoscopic polyps, frequently in patients with hypertension and history of malignancy. Polypoid LCPI may be a harbinger of LCPI in the background nonpolypoid colonic mucosa. A subset of polypoid LCPI (56%) cases represents true LC.

Transition Zone in Total Colonic Aganglionosis and Colorectal Hirschsprung's Disease Shows a Similar Trend of Mucosal Innervation: Image Processing and Analysis Study.

The aganglionic segment of bowel in Hirschsprung's disease (HD) varies in length. It is not clear whether total colonic aganglionosis (TCA) merely represents a long form of HD or a different phenotype of the disease. Animal model studies suggest that TCA may have a longer transition zone (TZ) than conventional colorectal HD. We compared mucosal innervation of TZ in 2 TCA cases and 10 conventional colorectal HD cases by quantifying calretinin-positive mucosal nerve fibers using image processing and analysis. One TCA was associated with esophageal atresia-tracheoesophageal fistula, the other with trisomy 21. The gradients of calretinin-stained pixel count increase per distance from the beginning of TZ (slope) for TCA were not significantly different from those for the conventional HD group. Given this observation, it is speculated that the length of TZ in TCA may fall within the range of and may not be much longer than conventional colorectal HD.

Gastric Lipohyperplasia Presenting as Gastric Polyposis: the First Case Report and Morphometric Study of Additional 127 Bariatric Specimens with a Proposal for Diagnostic Criteria.

INTRODUCTION: Excessive fat accumulation in the gastrointestinal tract is pathologic. Gastric mucosal polyposis due to excessive submucosal fat infiltration in a bariatric partial gastrectomy specimen was encountered, which has not been described in the literature. This observation prompted us to assess the extent of fat in gastric submucosa and study the incidence of mucosal polyposis due to submucosal fat accumulation in morbidly obese patients. MATERIALS AND METHODS: Archived pathology slides of 128 bariatric partial gastrectomy specimens including the index case and 89 control cases obtained from Whipple's procedure were examined. The amount of submucosal fat was categorized as 0 (no fat), 1 (up to 70% fat), and 2 (> 70% fat). The maximum submucosal fat thickness was measured with the interval cutoff of 5 mm and 10 mm. RESULTS: Of the 128 cases, 90 (70.3%) were category 1 and 31 (24.2%) were category 2. Maximum submucosal fat thickness was > 10 mm in 3 (2.3%) cases including the index case. The extent of submucosal fat accumulation correlated with the body mass index. The frequencies of category 2 and > 10 mm of fat thickness were higher in the bariatric patient group compared with the control group. CONCLUSION: We propose a submucosal fat thickness of > 10 mm and diffuse (> 70%) fat accumulation as diagnostic criteria for gastric lipohyperplasia. Using these criteria, the prevalence of gastric lipohyperplasia in the morbidly obese population is 2.3%. A subset of these may present as gastric mucosal polyps.

Rectal ulcer and pseudomalignant epithelial changes after prostate seed brachytherapy: A rare complication with a diagnostic pitfall.

BACKGROUND: Implant brachytherapy (IBT) is a well-recognized treatment modality for early stage prostate cancer. Rectal ulcer and rectourethral fistula complicating IBT may cause an alteration of the normal anatomic landmarks. In this context, pseudomalignant radiation-induced changes within prostatic epithelium may be misinterpreted as a primary rectal malignancy. Such challenging and misleading findings have not been described, and may not be recognized as such. MATERIALS AND METHODS: We present the clinical and pathologic aspects of two patients who underwent IBT for low stage prostate cancer that was complicated by deep rectal ulcer. Both patients underwent extensive palliative surgical resection for disease control. RESULTS: The histologic changes in both cases were noteworthy for extensive necrosis and inflammation of the prostate, associated with loss of recto-prostatic anatomical landmarks. Prostatic glands showed striking radiation-induced atypia and pseudomalignant epithelial changes extending to the rectal ulcer bed, with no residual viable tumor. The first patient had undergone a biopsy of the rectal ulcer bed that was misinterpreted as a rectal adenocarcinoma prior to surgery. The similarity between atypical glands of the biopsy and the benign prostatic tissue with radiation-induced atypia in resection specimen confirmed their benign nature. CONCLUSIONS: Deep rectal ulcer complicating IBT may lead to distortion of the normal recto-prostatic anatomical landmarks, resulting in detection of pseudo-malignant prostatic glands at the ulcer base. Such findings may be mistaken for a primary rectal malignancy in limited biopsy material if not familiar to the pathologist.

PD-L1 protein expression in tumour cells and immune cells in mismatch repair protein-deficient and -proficient colorectal cancer: the foundation study using the SP142 antibody and whole section immunohistochemistry.

AIMS: Routine application of PD-L1 immunohistochemistry (IHC) in colorectal cancer (CRC) is limited due to lack of standardized scoring criteria, antibody clones, and intratumoral staining heterogeneity. We assessed PD-L1 protein expression on full face CRC tissue sections and applied two algorithms based on the published clinical trials that support the recent FDA approval for immune checkpoint inhibitors (ICPI) therapy in non-small cell lung cancer (NSCLC). METHODS: PD-L1/CD274 IHC (Roche/Ventana, clone SP142) was performed on representative tumour blocks from 52 mismatch repair-deficient (MMR-D) and 52 MMR-proficient (MMR-P) CRCs. Membranous PD-L1 expression was scored for the tumour cell (TC) and tumour-infiltrating immune cell (IC) components. PD-L1 positivity status was determined based on the published NSCLC clinical trials that utilized the Ventana SP142 assay. Hybrid capture-based comprehensive genomic profiling (CGP) was performed on a separate set of 2268 clinically advanced CRCs and the frequency of PD-L1/PD-L2 amplification was determined. RESULTS: PD-L1 expression in the TC and IC correlated with MMR-D (p=0.013, p<0.0001), T stage (p=0.036, p=0.0036) and clinical stage (p=0.022, p=0.0037). PD-L1 positivity status correlated with MMR-D by two algorithms. Five of 2268 (<1%) advansced CRCs demonstrated amplification of either the PD-L1 or PD-L2 genes by CGP. CONCLUSIONS: PD-L1 expression in TC and IC is associated with advanced stage and MMR-D. PD-L1 positivity status by the published algorithm is associated with MMR-D. PD-L1 amplification is extremely uncommon in CRC. Evaluation of whole tissue section and incorporation of IC staining enhance the sensitivity to screen patients who may benefit from ICPI therapy.

Clinically advanced and metastatic pure mucinous carcinoma of the breast: a comprehensive genomic profiling study.

PURPOSE: Pure mucinous breast carcinoma (pmucBC) is a distinctive variant of breast cancer (BC) featuring an excellent overall prognosis. However, on rare occasions, pmucBC pursues an aggressive clinical course. We queried whether comprehensive genomic profiling (CGP) would uncover clinically relevant genomic alterations (CRGA) that could lead to targeted therapy treatment for patients with an advanced and metastatic form of pmucBC. METHODS: From a series of 51,238 total cancer samples, which included 5605 cases of clinically advanced BC and 22 cases of stage IV pmucBC, DNA was extracted from 40 microns of FFPE sections. Comprehensive genomic profiling was performed using a hybrid-capture, adaptor ligation-based next generation sequencing assay to a mean coverage depth of 564X. The results were analyzed for all classes of genomic alterations (GA) including base substitutions, insertions and deletions, select rearrangements, and copy number changes. Clinically relevant genomic alterations were defined as those indicating possible treatment with anti-cancer drugs on the market or in registered clinical trials. RESULTS: Samples were obtained from breast (11), lymph nodes (3), chest wall (2), liver (2), soft tissue (2), bone (1), and pleura (1). The median age of the 22 pmucBC patients was 57 years (range 32-79 years). Three pmucBCs were grade 1, 17 were grade 2, and 2 were grade 3. Twenty-one (95 %) pmucBC were ER+, 18 (82 %) were PR+, and 3 (14 %) were HER2+ by IHC and/or FISH. A total of 132 GA were identified (6.0 GA per tumor), including 53 CRGA, for a mean of 2.4 GA per tumor. Amplification of FGFR1 or ZNF703, located within the same amplicon, was found in 8 of 22 cases (36 %). This enrichment of FGFR1 amplification in 36 % of pmucBC versus 11 % of non-mucinous ER+ BC (601 cases) was significant (p < 0.005). Other frequently altered genes of interest in pmucBC were CCND1 and the FGF3/FGF4/FGF19 amplicon (27 %), often co-amplified together. ERBB2/HER2 alterations were identified in 5 pmucBC (23 %): ERBB2 amplification was found in 3 of 3 cases (100 %) that were HER2+ by IHC and/or FISH; 1 pmucBC was negative for HER2 overexpression by IHC, but positive for amplification by CGP; and 2 pmucBC harbored the ERBB2 substitutions D769Y and V777L (one sample also featured ERBB2 amplification). The enrichment of ERBB2 GA in metastatic pmucBC versus non-metastatic primary pmucBC was significant (p = 0.03). CRGA were also found in 20 additional genes including PIK3CA (5), BRCA1 (1), TSC2 (1), STK11 (1), AKT3 (1), and ESR1 (1). CONCLUSIONS: Metastatic pmucBC is a distinct form of breast cancer that features a relatively high frequency of CRGA, including a significant enrichment of FGFR1 alterations and a high frequency of ERBB2 alterations when compared with non-metastatic pmucBC. These findings suggest that CGP can identify a variety of known and emerging therapy targets that have the potential to improve outcomes for patients with clinically advanced and metastatic forms of this disease.

Genomic profiling of advanced-stage, metaplastic breast carcinoma by next-generation sequencing reveals frequent, targetable genomic abnormalities and potential new treatment options.

CONTEXT: Metastatic metaplastic breast carcinoma (MPBC) is an uncommon, but aggressive, tumor resistant to conventional chemotherapy. OBJECTIVE: To learn whether next-generation sequencing could identify potential targets of therapy for patients with relapsed and metastatic MPBC. DESIGN: Hybridization capture of 3769 exons from 236 cancer-related genes and 47 introns of 19 genes commonly rearranged in cancer was applied to a minimum of 50 ng of DNA extracted from 20 MPBC formalin-fixed, paraffin-embedded specimens and sequenced to high uniform coverage. RESULTS: The 20 patients with MPBC had a median age of 62 years (range, 42-86 years). There were 9 squamous (45%), 9 chondroid (45%), and 2 spindle cell (10%) MPBCs, all of which were high grade. Ninety-three genomic alterations were identified, (range, 1-11) with 19 of the 20 cases (95%) harboring an alteration that could potentially lead to a targeted treatment option. The most-common alterations were in TP53 (n = 69; 75%), PIK3CA (n = 37; 40%), MYC (n = 28; 30%), MLL2 (n = 28; 30%), PTEN (n = 23; 25%), CDKN2A/B (n = 19; 20%), CCND3 (n = 14; 15%), CCNE1 (n = 9; 10%), EGFR (n = 9; 10%), and KDM6A (n = 9; 10%); AKT3, CCND1, CCND2, CDK4, FBXW7, FGFR1, HRAS, NF1, PIK3R1, and SRC were each altered in a single case. All 16 MPBCs (100%) that were negative for ERBB2 (HER2) overexpression by immunohistochemistry and/or ERBB2 (HER2) amplification by fluorescence in situ hybridization were also uniformly (100%) negative for ERBB2 amplification by next-generation sequencing-based copy-number assessment. CONCLUSIONS: Our results indicate that genomic profiling using next-generation sequencing can identify clinically meaningful alterations that have the potential to guide targeted treatment decisions in most patients with metastatic MPBC.

Clinical next-generation sequencing successfully applied to fine-needle aspirations of pulmonary and pancreatic neoplasms.

BACKGROUND: Next-generation sequencing was performed on pulmonary and pancreatic fine-needle aspirations (FNAs) and on paired FNAs and resected primary tumors from the same patient. METHODS: DNA was isolated in formalin-fixed, paraffin-embedded cell blocks from 16 pulmonary FNAs, 23 pancreatic FNAs, and 5 resected pancreatic primary tumors. Next-generation sequencing was performed for 4561 exons of 287 cancer-related genes and for 47 introns of 19 genes on indexed, adaptor-ligated, hybridization-captured libraries using a proprietary sequencing system (the Illumina HiSeq 2000). RESULTS: Genomic profiles were generated successfully from 16 of 16 (100%) pulmonary FNAs, which included 14 nonsmall cell lung cancers (NSCLCs) and 2 small cell lung cancers (SCLCs). The NSCLC group included 6 adenocarcinomas, 5 squamous cell carcinomas, and 3 NSCLCs not otherwise specified. Genomic profiles were successfully obtained from 23 of 23 (100%) pancreatic FNAs and from 5 of 5 (100%) matched pancreatic primary tumors, which included 17 ductal adenocarcinomas, 3 mucinous adenocarcinomas, 2 adenocarcinomas NOS, and 1 neuroendocrine tumor. Eighty-one genomic alterations were identified in the 16 pulmonary FNAs (average, 5.1 genomic alterations per patient); and the most common genomic alterations were TP53, RB1, SOX2, PIK3CA, and KRAS. Eighty-seven genomic alterations were identified in the 23 pancreatic tumor FNAs (average, 3.8 genomic alterations per patient); and the most common genomic alterations were KRAS, TP53, CDKN2A/B, SMAD4, and PTEN. Among the pancreatic tumors, there was 100% concordance of 20 genomic alterations that were identified in 5 patient-matched FNA and surgical primary tumor pairs. CONCLUSIONS: The authors were able to perform next-generation sequencing reliably on FNAs of pulmonary and pancreatic tumors, and the genomic alterations discovered correlated well with those identified in matched resected pancreatic tumors.

Relapsed classic E-cadherin (CDH1)-mutated invasive lobular breast cancer shows a high frequency of HER2 (ERBB2) gene mutations.

PURPOSE: We queried whether comprehensive genomic profiling using a next-generation sequencing-based assay could identify novel and unanticipated targets of therapy for patients with relapsed invasive lobular carcinoma (ILC). EXPERIMENTAL DESIGN: DNA sequencing (Illumina HiSeq 2000) was conducted for 3,320 exons of 182 cancer-related genes and 37 introns of 14 genes frequently rearranged in cancer on indexed, adaptor-ligated, hybridization-captured libraries using DNA isolated from formalin-fixed paraffin-embedded sections from 22 histologically verified ILC. RESULTS: A total of 75 genomic alterations were identified with an average of 3.4 alterations per tumor (range, 1-6), of which 35 were actionable for an average of 1.59 actionable alterations per patient (range, 0-3). Nineteen of 22 (86%) of the ILC samples harbored at least one actionable alteration. Six (27%) cases featured alterations in ERRB2 including 4 (18%) with ERBB2 mutation, 1 (5%) with an ERBB2 gene fusion, and 1 (5%) with an ERBB2 copy number gain (amplification). The enrichment of ERBB2 mutations/fusion in CDH1-mutated ILC (5 of 22, 23%) compared with the 5 ERBB2 mutations in a series of 286 non-CDH1-mutated breast cancers from which the ILC cases were obtained (5 of 286, 2%) was significant (P = 0.0006). CONCLUSIONS: Comprehensive genomic profiling of relapsed CDH1-mutated ILC revealed actionable genomic alterations in 86% of cases, featured a high incidence of ERBB2 alterations, and can reveal actionable alterations that can inform treatment decisions for patients with ILC.

Overexpression of WWP1 is associated with the estrogen receptor and insulin-like growth factor receptor 1 in breast carcinoma.

WWP1, a HECT type E3 ubiquitin ligase frequently amplified and overexpressed in breast cancer, has the potential to become a useful clinical biomarker and therapeutic target in breast cancer. Here, we performed immunohistochemical staining in formalin-fixed and paraffin-embedded tissue sections from 187 cases of primary invasive mammary carcinoma [137 ductal carcinomas (IDC) and 50 lobular carcinomas (ILC)] by using a monoclonal anti-WWP1 antibody. The normal breast epithelium and adjacent benign epithelium are essentially negative for WWP1. Cytoplasmic WWP1 immunoreactivity was observed in 76/187 (40.6%) tumors and showed a positive correlation with ERalpha (p = 0.05) and IGF-1R proteins (p = 0.001) in this cohort. The positive correlations between WWP1 and ER/IGF-1R were also observed in a panel of 12 breast cancer cell lines by Western blot. Interestingly, the ER levels are decreased when WWP1 is silenced in ER positive MCF7 and T47D breast cancer cell lines. Finally, WWP1 ablation collectively inhibits cell proliferation with tamoxifen in MCF7 and T47D, as measured by (3)H-thymidine incorporation assays. These findings suggest that WWP1 may play an important role in ER positive breast cancer.

DNA ploidy and cell cycle analysis in breast cancer.

During the past 10 years there has been considerable interest in the application of new technologies to identify human malignancy and predict disease outcome. Markers of cell proliferation and the technologies of flow cytometry and image analysis for the determination of DNA total content in human tumor cells have been studied in breast cancer for 20 years. In this review, the uses and limitations of these technologies for the determination of ploidy status are discussed. This review also considers the prognostic significance and potential clinical utility of ploidy measurements, S phase calculation, and individual cell cycle regulatory biomarker expression levels.

Adrenal Pseudocysts: Evidence of Their Posthemorrhagic Nature.

Hemorrhagic adrenal pseudocysts are uncommon nonneoplastic lesions that have been reported as secondary to intraparenchymal hemorrhage or alternatively related to endothelial (vascular) cysts. Ultrastructural and ammunohistochemical evidence in support of the latter has been presented, but the exact nature of hemorrhagic adrenal pseudocysts remains poorly defined. We evaluated six surgical specimens of hemorrhagic adrenal pseudocysts using immunohistochemical staining for CD31 and CD34, as well as conventional histochemistry. All six cases had hemorrhagic contents within a wall of variable thickness possessing focal areas of linear, disrupted elastin, and smooth muscle. Three cases demonstrated extensive thrombosis with organization, including papillary endothelial hyperplasia, simulating angiosarcoma. In these cases, CD3I and CD34 staining decorated areas of papillary endothelial hyperplasia as well as foci of the internal cyst lining, whereas the other cases were negative for both antibodies. Of interest is the history of FNA prior to surgical resection in three cases of hemorrhagic adrenal pseudocysts, two of which showed papillary endothelial hyperplasia. The presence of papillary endothelial hyperplasia and our immunohistochemical findings support the conclusion that adrenal pseudocysts are posthemorrhagic and derive from vascular disruption. Furthermore, FNA or other interventional studies may be associated with papillary endothelial hyperplasia in hemorrhagic adrenal pseudocysts.