Artificial Intelligence-Triaged 3-Dimensional Pathology to Improve Detection of Esophageal Neoplasia While Reducing Pathologist Workloads.

Early detection of esophageal neoplasia via evaluation of endoscopic surveillance biopsies is the key to maximizing survival for patients with Barrett's esophagus, but it is hampered by the sampling limitations of conventional slide-based histopathology. Comprehensive evaluation of whole biopsies with 3-dimensional (3D) pathology may improve early detection of malignancies, but large 3D pathology data sets are tedious for pathologists to analyze. Here, we present a deep learning-based method to automatically identify the most critical 2-dimensional (2D) image sections within 3D pathology data sets for pathologists to review. Our method first generates a 3D heatmap of neoplastic risk for each biopsy, then classifies all 2D image sections within the 3D data set in order of neoplastic risk. In a clinical validation study, we diagnose esophageal biopsies with artificial intelligence-triaged 3D pathology (3 images per biopsy) vs standard slide-based histopathology (16 images per biopsy) and show that our method improves detection sensitivity while reducing pathologist workloads.

Non-Canonical Activin A Signaling Stimulates Context-Dependent and Cellular-Specific Outcomes in CRC to Promote Tumor Cell Migration and Immune Tolerance.

We have shown that activin A (activin), a TGF-ß superfamily member, has pro-metastatic effects in colorectal cancer (CRC). In lung cancer, activin activates pro-metastatic pathways to enhance tumor cell survival and migration while augmenting CD4+ to CD8+ communications to promote cytotoxicity. Here, we hypothesized that activin exerts cell-specific effects in the tumor microenvironment (TME) of CRC to promote anti-tumoral activity of immune cells and the pro-metastatic behavior of tumor cells in a cell-specific and context-dependent manner. We generated an Smad4 epithelial cell specific knockout (Smad4-/-) which was crossed with TS4-Cre mice to identify SMAD-specific changes in CRC. We also performed IHC and digital spatial profiling (DSP) of tissue microarrays (TMAs) obtained from 1055 stage II and III CRC patients in the QUASAR 2 clinical trial. We transfected the CRC cells to reduce their activin production and injected them into mice with intermittent tumor measurements to determine how cancer-derived activin alters tumor growth in vivo. In vivo, Smad4-/- mice displayed elevated colonic activin and pAKT expression and increased mortality. IHC analysis of the TMA samples revealed increased activin was required for TGF-ß-associated improved outcomes in CRC. DSP analysis identified that activin co-localization in the stroma was coupled with increases in T-cell exhaustion markers, activation markers of antigen presenting cells (APCs), and effectors of the PI3K/AKT pathway. Activin-stimulated PI3K-dependent CRC transwell migration, and the in vivo loss of activin lead to smaller CRC tumors. Taken together, activin is a targetable, highly context-dependent molecule with effects on CRC growth, migration, and TME immune plasticity.

Nondestructive 3D Pathology Image Atlas of Barrett Esophagus With Open-Top Light-Sheet Microscopy.

CONTEXT.­: Anatomic pathologists render diagnosis on tissue samples sectioned onto glass slides and viewed under a bright-field microscope. This approach is destructive to the sample, which can limit its use for ancillary assays that can inform patient management. Furthermore, the subjective interpretation of a relatively small number of 2D tissue sections per sample contributes to low interobserver agreement among pathologists for the assessment (diagnosis and grading) of various lesions. OBJECTIVE.­: To evaluate 3D pathology data sets of thick formalin-fixed Barrett esophagus specimens imaged nondestructively with open-top light-sheet (OTLS) microscopy. DESIGN.­: Formalin-fixed, paraffin-embedded Barrett esophagus samples (N = 15) were deparaffinized, stained with a fluorescent analog of hematoxylin-eosin, optically cleared, and imaged nondestructively with OTLS microscopy. The OTLS microscopy images were subsequently compared with archived hematoxylin-eosin histology sections from each sample. RESULTS.­: Barrett esophagus samples, both small endoscopic forceps biopsies and endoscopic mucosal resections, exhibited similar resolvable structures between OTLS microscopy and conventional light microscopy with up to a ×20 objective (×200 overall magnification). The 3D histologic images generated by OTLS microscopy can enable improved discrimination of cribriform and well-formed gland morphologies. In addition, a much larger amount of tissue is visualized with OTLS microscopy, which enables improved assessment of clinical specimens exhibiting high spatial heterogeneity. CONCLUSIONS.­: In esophageal specimens, OTLS microscopy can generate images comparable in quality to conventional light microscopy, with the advantages of providing 3D information for enhanced evaluation of glandular morphologies and enabling much more of the tissue specimen to be visualized nondestructively.

KRAS Mutation Variants and Co-occurring PI3K Pathway Alterations Impact Survival for Patients with Pancreatic Ductal Adenocarcinomas.

BACKGROUND: KRAS variant alleles may have differential biological properties which impact prognosis and therapeutic options in pancreatic ductal adenocarcinomas (PDA). MATERIALS AND METHODS: We retrospectively identified patients with advanced PDA who received first-line therapy and underwent blood and/or tumor genomic sequencing at the University of Washington between 2013 and 2020. We examined the incidence of KRAS mutation variants with and without co-occurring PI3K or other genomic alterations and evaluated the association of these mutations with clinicopathological characteristics and survival using a Cox proportional hazards model. RESULTS: One hundred twenty-six patients had genomic sequencing data; KRAS mutations were identified in 111 PDA and included the following variants: G12D (43)/G12V (35)/G12R (23)/other (10). PI3K pathway mutations (26% vs. 8%) and homologous recombination DNA repair (HRR) defects (35% vs. 12.5%) were more common among KRAS G12R vs. non-G12R mutated cancers. Patients with KRAS G12R vs. non-G12R cancers had significantly longer overall survival (OS) (HR 0.55) and progression-free survival (PFS) (HR 0.58), adjusted for HRR pathway co-mutations among other covariates. Within the KRAS G12R group, co-occurring PI3K pathway mutations were associated with numerically shorter OS (HR 1.58), while no effect was observed on PFS. CONCLUSIONS: Patients with PDA harboring KRAS G12R vs. non-G12R mutations have longer survival, but this advantage was offset by co-occurring PI3K alterations. The KRAS/PI3K genomic profile could inform therapeutic vulnerabilities in patients with PDA.

Cokeromyces recurvatus Incidentally Found in a Patient with Gastric Outlet Obstruction.

Isolation of Cokeromyces recurvatus, a dimorphic mucormycete fungus, from clinical specimens poses a diagnostic challenge to physicians and laboratorians as this organism may represent a rare colonizer or true pathogen. Here, we report a case of Cokeromyces recurvatus present in a circumferential duodenal lesion. The patient is a 64-year-old with no past medical history, admitted with a three-week history of left upper quadrant abdominal pain. Computerized tomography scan identified duodenitis with significant gastric outlet obstruction, confirmed by the presence of a partially obstructing non-bleeding duodenal ulcer on upper endoscopy. Histology showed variably sized spherical structures without nuclei, reproductive tracts, or alimentary tracts. Small, clustered spherules representing putative endospores were observed within the larger structures and in the exudate. Based on the histology, the differential included Coccidioides spp, Emmonsia spp, or Chrysosporium spp. Additionally, gastric biopsies revealed concurrent Helicobacter pylori gastritis. The fungus was identified as C. recurvatus by broad-range fungal polymerase chain reaction performed on formalin-fixed paraffin-embedded biopsy tissue, as well as morphology and DNA sequencing of the cultured isolate. The fungus had low MICs to all major antifungal classes; however, in the context of the Helicobacter pylori infection, the patient was only treated with amoxicillin and clarithromycin with improvement in his symptoms before hospital discharge. Only three cases of Cokeromyces recurvatus isolated from the GI tract have been reported; this case highlights a unique clinical presentation in the small bowel in a patient without underlying medical conditions.

Novel DNA Methylation Biomarker Panel for Detection of Esophageal Adenocarcinoma and High-Grade Dysplasia.

PURPOSE: Current endoscopy-based screening and surveillance programs have not been proven effective at decreasing esophageal adenocarcinoma (EAC) mortality, creating an unmet need for effective molecular tests for early detection of this highly lethal cancer. We conducted a genome-wide methylation screen to identify novel methylation markers that distinguish EAC and high-grade dysplasia (HGD) from normal squamous epithelium (SQ) or nondysplastic Barrett's esophagus (NDBE). EXPERIMENTAL DESIGN: DNA methylation profiling of samples from SQ, NDBE, HGD, and EAC was performed using HM450 methylation arrays (Illumina) and reduced-representation bisulfate sequencing. Ultrasensitive methylation-specific droplet digital PCR and next-generation sequencing (NGS)-based bisulfite-sequencing assays were developed to detect the methylation level of candidate CpGs in independent esophageal biopsy and endoscopic brushing samples. RESULTS: Five candidate methylation markers were significantly hypermethylated in HGD/EAC samples compared with SQ or NDBE (P < 0.01) in both esophageal biopsy and endoscopic brushing samples. In an independent set of brushing samples used to construct biomarker panels, a four-marker panel (model 1) demonstrated sensitivity of 85.0% and 90.8% for HGD and EACs respectively, with 84.2% and 97.9% specificity for NDBE and SQ respectively. In a validation set of brushing samples, the panel achieved sensitivity of 80% and 82.5% for HGD and EAC respectively, at specificity of 67.6% and 96.3% for NDBE and SQ samples. CONCLUSIONS: A novel DNA methylation marker panel differentiates HGD/EAC from SQ/NDBE. DNA-methylation-based molecular assays hold promise for the detection of HGD/EAC using esophageal brushing samples.

AKR1C3 expression in T acute lymphoblastic leukemia/lymphoma for clinical use as a biomarker.

To investigate aldo-keto reductase 1C3 (AKR1C3) expression in T and B acute lymphoblastic leukemia/lymphoma (ALL) patients. Three commercial antibodies were evaluated for AKR1C3 immunohistochemistry (IHC) staining performance: Polyclonal Thermofisher scientific (Clone#PA523667), rabbit monoclonal Abcam [EPR16726] (ab209899) and Sigma/Millipore anti-AKR1C3 antibody, mouse monoclonal, clone NP6.G6.A6, purified from hybridoma cell culture. Initial optimization was performed on cell line controls: HCT116 (negative control); genetically modified cell line HCT116 with AKR1C3 overexpression; Nalm and TF1 cell lines. Twenty normal bone marrows from archival B and T-ALL patient samples were subsequently examined. AKR1C3 expression levels in these samples were evaluated by immunohistochemistry, Protein Wes and quantitative RT-PCR. Sigma/Millipore Anti-AKR1C3 antibody (mouse monoclonal, clone NP6.G6.A6) showed higher specificity compared to rabbit polyclonal antibody by immunohistochemistry. H-score was used to quantify percent of nuclear immunoreactivity for AKR1C3 with varying disease involvement. T-ALL samples had a higher H-score (172-190) compared to B-ALL cases (H-score, 30-160). The AKR1C3 expression in peripheral blood by Protein Wes and RT-qPCR showed concordance in relapsed/refractory and/or minimal residual T-ALL cases. Sigma/Millipore Anti-AKR1C3 antibody and mouse monoclonal, clone NP6.G6.A6 can be used to aid in AKR1C expression of T-ALL and in cases of relapsed/refractory and/or minimal residual disease.

Clinicopathologic Findings in Patients With Initial Diagnosis of Extranodal Marginal Zone B-Cell Lymphoma of Mucosa-Associated Lymphoid Tissue (MALT) in Colorectal Mucosa.

OBJECTIVES: To evaluate clinicopathologic features, management, and behavior of colorectal extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT). METHODS: Clinical data, laboratory studies, and radiographic records were reviewed (2005-2018), and fluorescence in situ hybridization studies were performed. RESULTS: Eleven patients were identified, six of whom were discovered as an incidental finding on endoscopy. Morphologic and immunophenotypic features were similar to MALT lymphomas at other sites except that lymphoepithelial lesions were uncommon. Three of nine patients were positive for BIRC3/MALT1 fusions, two of whom had identical B-cell clones identified in subsequent gastric biopsy specimens. Eight of 10 patients had no clinically evaluable disease after observation (±antibiotics; n = 4) or radiation/chemotherapy (n = 4). CONCLUSIONS: Patients with incidental and localized colonic MALT lymphoma demonstrated an excellent prognosis with conservative management, although longer follow-up and data based on consistent staging and surveillance methods (including gastric evaluation) are necessary for informed management.

Sequential Development of JAK2V617F Mutation and BCR-ABL1 Fusion in Individual Patients With Myeloproliferative Neoplasms.

CONTEXT.­: Concomitant BCR-ABL1 and JAK2V617F in myeloproliferative neoplasms (MPNs) is rare, and its pathogenesis and clinical significance are unclear. OBJECTIVE.­: To investigate the clonal relationship between the 2 genomic alterations, as well as the clinicopathologic impact. DESIGN.­: Retrospective analysis of MPNs with sequential development of BCR-ABL1 and JAK2V617F. RESULTS.­: Of 6 cases, 5 had JAK2V617F-positive MPN diagnosed before acquiring BCR-ABL1 years later, and 1 had BCR-ABL1+ chronic myeloid leukemia before JAK2V617F-positive myelofibrosis completely replaced the BCR-ABL1+ clone 1 year after tyrosine kinase inhibitor therapy. Among the former group, treatment for the initial MPN involved hydroxyurea, ruxolitinib, and/or supportive care, and the latency to the development of JAK2V617F ranged from 4 to 13 years (median of 9 years). Four cases showed retention of JAK2V617F, whereas BCR-ABL1 emerged as the major clone, including 2 cases that exhibited parallel increases in JAK2V617F and BCR-ABL1 burdens, with both genomic markers exceeding 50%. Three patients received stem cell transplants and demonstrated sustained engraftment, with the genomic markers below detectable levels. CONCLUSIONS.­: Most MPNs with concomitant JAK2V617F and BCR-ABL1 are actually composite MPNs with a "second hit" residing on a different clone. Rare cases demonstrate a subclone harboring a "double-hit" in a background of a JAK2V617F-positive stem line clone. The probability of a "double-hit" with a BCR-ABL1+ stem line clone is probably reduced by effective tyrosine kinase inhibitor treatment. The treatment often involves combined kinase inhibitors and/or hydroxyurea, but the outcome is unpredictable; hematopoietic stem cell transplantation may be the ultimate therapeutic option for this complicated disease.

Clinical Characteristics and Outcomes of Colorectal Cancer in the ColoCare Study: Differences by Age of Onset.

Early-onset colorectal cancer has been on the rise in Western populations. Here, we compare patient characteristics between those with early- (<50 years) vs. late-onset (≥50 years) disease in a large multinational cohort of colorectal cancer patients (n = 2193). We calculated descriptive statistics and assessed associations of clinicodemographic factors with age of onset using mutually-adjusted logistic regression models. Patients were on average 60 years old, with BMI of 29 kg/m2, 52% colon cancers, 21% early-onset, and presented with stage II or III (60%) disease. Early-onset patients presented with more advanced disease (stages III-IV: 63% vs. 51%, respectively), and received more neo and adjuvant treatment compared to late-onset patients, after controlling for stage (odds ratio (OR) (95% confidence interval (CI)) = 2.30 (1.82-3.83) and 2.00 (1.43-2.81), respectively). Early-onset rectal cancer patients across all stages more commonly received neoadjuvant treatment, even when not indicated as the standard of care, e.g., during stage I disease. The odds of early-onset disease were higher among never smokers and lower among overweight patients (1.55 (1.21-1.98) and 0.56 (0.41-0.76), respectively). Patients with early-onset colorectal cancer were more likely to be diagnosed with advanced stage disease, to have received systemic treatments regardless of stage at diagnosis, and were less likely to be ever smokers or overweight.

Esophageal granular cell tumor and eosinophils: a multicenter experience.

BACKGROUND: Esophageal granular cell tumor (eGCT) is rare, and the recent literature suggests a link between eosinophilic esophagitis (EoE) and eGCT. The aim of our study was to determine if EoE or other disorders associated with eosinophilia are consistently associated with eGCT. METHODS: We retrospectively searched pathology databases of three academic institutions from 1999 to 2018 for eGCTs. The archived slides and medical records were reviewed. RESULTS: From 294,855 esophagogastroduodenoscopy procedures, 45 patients (17 males and 28 females) with eGCTs were identified. The patients (30-73 years in age, median 50) had eGCT 0.2-2.0 cm in size (average 0.71). Thirteen had a history of gastroesophageal reflux disease, 5 had Barrett esophagus/goblet cell metaplasia and 1 had EoE. Thirty-four eGCTs had intralesional eosinophils (14 with peak > 10 eosinophils/400x hpf); of these, 21 also had eosinophils in lamina propria (9 with peak > 10 eosinophils/hpf). eGCT with atypical features (including nuclear enlargement and prominent nucleoli) were more likely to have increased eosinophils in non-epithelial compartments than those without atypia. Pleomorphism and spindled cells were seen in 3 eGCT cases (mean peak intralesional eosinophils: 43 per hpf); 2 of these had goblet cell metaplasia. We found no association between EoE and eGCT, p = 0.5966, (95% C.I. 0.0276, 6.5389, Fisher's exact test). Instead, most patients had gastroesophageal reflux disease or Barrett esophagus. CONCLUSION: Eosinophilia, common in eGCT and adjacent stroma, likely drives atypical/reactive histologic features, but a pathogenic relationship between eosinophil rich inflammatory conditions and eGCT has not yet been established.

Serology Is More Sensitive Than Urea Breath Test or Stool Antigen for the Initial Diagnosis of Helicobacter pylori Gastritis When Compared With Histopathology.

OBJECTIVES: To assess the concordance and performance characteristics of Helicobacter pylori laboratory tests compared with histopathology and to propose algorithms for the diagnosis of H pylori that minimize diagnostic error. METHODS: H pylori diagnostics were reviewed from a 12-year period within a health system (2,560 cases). Analyses were performed to adjust diagnostic performance based on treatment and consensus histopathologic diagnoses among pathologists. Markers of access to care, including test cancellation frequency and turnaround time, were assessed. Costs and performance of candidate noninvasive testing algorithms were modeled as a function of disease prevalence. RESULTS: Serum H pylori IgG demonstrated a higher sensitivity (0.94) than urea breath and stool antigen tests (0.64 and 0.61, respectively). Evidence of an advantage in access to care for serology included a lower cancellation rate. Interobserver variability was higher (κ = 0.34) among pathologists for cases with a discordant laboratory test than concordant cases (κ = 0.56). A model testing algorithm utilizing serology for first-time diagnoses minimizes diagnostic error. CONCLUSIONS: Although H pylori serology has modestly lower specificity than other noninvasive tests, the superior sensitivity and negative predictive value in our population support its use as a noninvasive test to rule out H pylori infection. Reflexive testing with positive serology followed by either stool antigen or urea breath test may optimize diagnostic accuracy in low-prevalence populations.

Rapidly Growing Pancreatic Adenocarcinoma Presenting as an Irreducible Umbilical Hernia.

Hernia sacs are a common anatomic pathology specimen, which rarely contain malignancy. We present a case of rapidly growing pancreatic adenocarcinoma, which initially presented as metastasis to an umbilical hernia sac. The patient was a 55-year-old male with a two-year history of umbilical hernia. Two months prior to herniorrhaphy, the hernia became painful and the patient experienced nausea and weight loss. The gross examination did not reveal distinct lesions. Microscopically, the hernia sac was diffusely infiltrated by moderately differentiated adenocarcinoma, which was positive for CK7 and pancytokeratin and negative for TTF-1, CK20, PSA, and CDX2. Clinical laboratory tests found elevated levels of CA 19-9 and CEA. Computed tomography scan with intravenous contrast showed a 5 cm ill-defined and hypoattenuating mass involving the pancreatic tail and body, as well as numerous ill-defined lesions in the liver and peritoneal carcinomatosis. The patient had an earlier noncontrast computed tomography scan four months prior to the surgery, which did not detect any lesions in the abdomen. This case highlights the importance of intravenous contrast with computed tomography for the evaluation of pancreatic lesions and also emphasizes the importance of thorough histologic evaluation of hernia sacs for the detection of occult malignancy.

Grade Assignment by Ki-67 Proliferative Index, Mitotic Count, and Phosphohistone H3 Count in Surgically Resected Gastrointestinal and Pancreatic Neuroendocrine Tumors.

OBJECTIVES: The aim of this study was to evaluate the concordance in grade assignment for gastroenteropancreatic neuroendocrine tumors using mitotic count (MC), Ki-67 proliferative index (KPI), and phosphohistone H3 count (PHH3C). METHODS: Resected gastroenteropancreatic neuroendocrine tumors were graded based on MC, KPI, and PHH3C. Concordance was determined using a weighted κ statistic. Median survival across each grade category was determined using Kaplan-Meier methods. RESULTS: Of the 110 patients, the majority had gastrointestinal primaries and grade 1 or 2 tumors. Rates of discordance in grade assignment were 29% of cases for KPI versus MC (κW = 0.26), 32% for PHH3C versus MC (κW = 0.34), and 32% for PHH3C versus KPI (κW = 0.37). There was fair agreement between grading by KPI and MC. Relative to grade by KPI and MC, PHH3C tended to upgrade tumors. The proportion alive at 3 and 5 years was not significantly different for patients with grade 1 versus grade 2 tumors. CONCLUSIONS: The concordance between KPI and MC was fair. Phosphohistone H3 count tended to upgrade tumors using the cutoffs established by MC. Grade 1 and grade 2 tumors were associated with similar survival regardless of grading method. The overall relevance of the current cutoff values used in grading neuroendocrine tumors may need to be revisited.

Acquisition of CD30 and CD15 accompanied with simultaneous loss of all pan-T-cell antigens in a case of histological transformation of mycosis fungoides with involvement of regional lymph node: an immunophenotypic alteration resembling classical Hodgkin lymphoma.

: Acquired expression of CD30 is frequently noted in histological transformation of mycosis fungoides (MF), but simultaneous gain of CD15 accompanied with loss of pan-T-cell antigens are extremely rare. We report an unusual case of transformed MF with such an immunophenotypic alteration resembling classical Hodgkin lymphoma. The patient was an 81-year-old male with MF, who was initially treated with topical steroids and phototherapy. Despite the initial response, the patient developed a tumor-like skin lesion that was confirmed to be CD30-positive large T-cell lymphoma and was subsequently found to have a regional lymph node involvement by pleomorphic large cell lymphoma. Besides CD30, pleomorphic large cells were positive for CD15 but negative for all B cell- and T cell-specific antigens. Epstein-Barr virus was negative. Polymerase chain reaction-based assays demonstrated a clonal rearrangement of T-cell receptor gamma gene but detected no B-cell clone. The mechanism and clinical significance of this phenotypic conversion remains to be elucidated.

Clinical and pathologic analysis of extramedullary tumors after hematopoietic stem cell transplantation.

Clinical and pathologic analyses of 41 extramedullary biopsy/resection specimens of extramedullary tumors (EMTs) after hematopoietic stem cell transplantation (HSCT) were performed. The 41 EMT specimens were from 28 patients, with 11 having more than 1 consecutive EMT in different anatomic locations at different times post-HSCT. The median age at EMT diagnosis was 45 years (range, 17-73 years), and the male/female ratio was 17:11. The most common initial diagnosis was acute myeloid leukemia (21), followed by chronic myeloid leukemia with myeloid blast phase (2), primary myelofibrosis with acute leukemic transformation (1), acute lymphoblastic leukemia (2), mixed lineage T/myeloid leukemia (1), and plasma cell myeloma (1). All initial presentations were limited to bone marrow-only disease. Twenty patients had abnormal chromosomal karyotypes, whereas 6 had normal cytogenetics with their original disease. All patients received standard chemotherapy followed by allogeneic (27) or autologous (1) HSCT. The EMTs occurred 2 to 177 months (median, 16.5 months) after HSCT and were diagnosed as solid mass lesions as follows: skin and soft tissue (10), central nervous system and paraspinal tissue (9), breast (7), gastrointestinal tract (4), lymph node (4), genitourinary system (4), and mediastinum (3). Interestingly, all but 3 patients had negative bone marrows at the time their EMT was diagnosed, indicating that most EMTs presented as sole lesion of relapsed disease. The overall outcome was dismal for patients with EMT, with 20 (71%) of 28 patients deceased at 1 to 26 months after EMT diagnosis, with a median overall survival of only 6.5 months.

Composite lymphoid neoplasm of B-cell and T-cell origins: a pathologic study of 14 cases.

We retrospectively analyzed 14 composite lymphoma/lymphoid neoplasms (CL) of B-cell/T-cell origins. These consisted of a spectrum of T-cell neoplasms in combination with different B-cell lymphomas/leukemias, with peripheral T-cell lymphoma and diffuse large B-cell lymphoma encountered most frequently for each respective neoplastic lineage. Histopathologic evaluation demonstrated 6 patterns of neoplastic distribution, including zone, inverted zone, diffuse mixed, regional/nodular mixed, compartmental, and segmental distributions. Four of 9 cases studied were positive for Epstein-Barr virus, all with a mixed pattern, suggesting that this pattern may predict an Epstein-Barr virus association. None of 14 cases was considered CL at the initial histologic evaluation. Only 6 (46.2%) of 13 cases had coexisting B-cell/T-cell neoplasms highlighted by immunohistochemistry, and the other 7 (53.8%) cases had 1 or both of the neoplastic components hidden. Flow cytometry detected both neoplastic lineages in 4 (44%) but failed to detect a clonal B-cell population in 4 (44%) and missed neoplastic T cells in 1 (11.1%) of 9 cases. Molecular testing detected clonal rearrangement of IGH/K gene in 11 (84.6%) of 13 cases, and clonal rearrangement of the TCRG/B gene in 13 (92.9%) of 14 cases, including 8 with identical amplicons detected in separate samples. CLs of B-cell/T-cell origin are heterogeneous in subtype combination and topographic pattern, often with one of the components histologically occult. A multidisciplinary approach is emphasized to establish a definitive diagnosis in these challenging cases.

Dysregulated ΔNp63α negatively regulates the maspin promoter in keratinocytes via blocking endogenous p73 binding.

While overexpression of the p63 isoform, ΔNp63α, has been reported in squamous cell cancers, the contribution of p63 to cancer pathogenesis remains unclear. We previously demonstrated that overexpressed ΔNp63α aberrantly maintains proliferation of primary mouse keratinocytes under conditions that normally induce growth arrest and differentiation. To identify genes downstream of dysregulated ΔNp63α that may contribute to squamous cancer development and progression, we performed microarray analyses using primary mouse keratinocytes. Herein we report that elevated ΔNp63α differentially regulates genes involved in a variety of cellular functions. Of note, multiple protease inhibitor mRNAs were downregulated including: maspin (serpinB5); plasminogen activator inhibitor-2 (PAI-2; serpinB2); and tissue inhibitor of metalloproteinase-3 (TIMP-3). Correspondingly, secreted TIMP-3 and PAI-2 protein declined in the presence of dysregulated ΔNp63α, however secreted maspin remained stable. Intracellular maspin protein expression decreased in response to overexpressed ΔNp63α, as did PAI-2. In contrast, TIMP-3 protein was not detected intracellularly, supporting a solely extracellular function. Electrophoretic mobility shift assays (EMSAs) using a maspin promoter p53/p63 consensus sequence revealed endogenous transcription factor(s) binding to this sequence in keratinocytes that was disrupted by overexpressed ΔNp63α. This was confirmed by ChIP assays. This binding was interrupted by the addition of antibodies recognizing p73, but not p53 or p63, and significantly diminished in EMSA reactions from p73(-/-) keratinocytes, confirming p73 as a constituent. Physical association between p73/ΔNp63α was observed in control ß-gal overexpressing keratinocytes and was enhanced in the presence of overexpressed ΔNp63α These findings underscore the importance of properly balanced p53 homologs for tissue homeostasis.