PTEN deficiency induces an extrahepatic cholangitis-cholangiocarcinoma continuum via aurora kinase A in mice.

BACKGROUND & AIMS: The PTEN-AKT pathway is frequently altered in extrahepatic cholangiocarcinoma (eCCA). We aimed to evaluate the role of PTEN in the pathogenesis of eCCA and identify novel therapeutic targets for this disease. METHODS: The Pten gene was genetically deleted using the Cre-loxp system in biliary epithelial cells. The pathologies were evaluated both macroscopically and histologically. The characteristics were further analyzed by immunohistochemistry, reverse-transcription PCR, cell culture, and RNA sequencing. Some features were compared to those in human eCCA samples. Further mechanistic studies utilized the conditional knockout of Trp53 and Aurora kinase A (Aurka) genes. We also tested the effectiveness of an Aurka inhibitor. RESULTS: We observed that genetic deletion of the Pten gene in the extrahepatic biliary epithelium and peri-ductal glands initiated sclerosing cholangitis-like lesions in mice, resulting in enlarged and distorted extrahepatic bile ducts in mice as early as 1 month after birth. Histologically, these lesions exhibited increased epithelial proliferation, inflammatory cell infiltration, and fibrosis. With aging, the lesions progressed from low-grade dysplasia to invasive carcinoma. Trp53 inactivation further accelerated disease progression, potentially by downregulating senescence. Further mechanistic studies showed that both human and mouse eCCA showed high expression of AURKA. Notably, the genetic deletion of Aurka completely eliminated Pten deficiency-induced extrahepatic bile duct lesions. Furthermore, pharmacological inhibition of Aurka alleviated disease progression. CONCLUSIONS: Pten deficiency in extrahepatic cholangiocytes and peribiliary glands led to a cholangitis-to-cholangiocarcinoma continuum that was dependent on Aurka. These findings offer new insights into preventive and therapeutic interventions for extrahepatic CCA. IMPACT AND IMPLICATIONS: The aberrant PTEN-PI3K-AKT signaling pathway is commonly observed in human extrahepatic cholangiocarcinoma (eCCA), a disease with a poor prognosis. In our study, we developed a mouse model mimicking cholangitis to eCCA progression by conditionally deleting the Pten gene via Pdx1-Cre in epithelial cells and peribiliary glands of the extrahepatic biliary duct. The conditional Pten deletion in these cells led to cholangitis, which gradually advanced to dysplasia, ultimately resulting in eCCA. The loss of Pten heightened Akt signaling, cell proliferation, inflammation, fibrosis, DNA damage, epigenetic signaling, epithelial-mesenchymal transition, cell dysplasia, and cellular senescence. Genetic deletion or pharmacological inhibition of Aurka successfully halted disease progression. This model will be valuable for testing novel therapies and unraveling the mechanisms of eCCA tumorigenesis.

Non-invasive detection of cardiac allograft rejection among heart transplant recipients using an electrocardiogram based deep learning model.

Aims: Current non-invasive screening methods for cardiac allograft rejection have shown limited discrimination and are yet to be broadly integrated into heart transplant care. Given electrocardiogram (ECG) changes have been reported with severe cardiac allograft rejection, this study aimed to develop a deep-learning model, a form of artificial intelligence, to detect allograft rejection using the 12-lead ECG (AI-ECG). Methods and results: Heart transplant recipients were identified across three Mayo Clinic sites between 1998 and 2021. Twelve-lead digital ECG data and endomyocardial biopsy results were extracted from medical records. Allograft rejection was defined as moderate or severe acute cellular rejection (ACR) based on International Society for Heart and Lung Transplantation guidelines. The extracted data (7590 unique ECG-biopsy pairs, belonging to 1427 patients) was partitioned into training (80%), validation (10%), and test sets (10%) such that each patient was included in only one partition. Model performance metrics were based on the test set (n = 140 patients; 758 ECG-biopsy pairs). The AI-ECG detected ACR with an area under the receiver operating curve (AUC) of 0.84 [95% confidence interval (CI): 0.78-0.90] and 95% (19/20; 95% CI: 75-100%) sensitivity. A prospective proof-of-concept screening study (n = 56; 97 ECG-biopsy pairs) showed the AI-ECG detected ACR with AUC = 0.78 (95% CI: 0.61-0.96) and 100% (2/2; 95% CI: 16-100%) sensitivity. Conclusion: An AI-ECG model is effective for detection of moderate-to-severe ACR in heart transplant recipients. Our findings could improve transplant care by providing a rapid, non-invasive, and potentially remote screening option for cardiac allograft function.

Umbralisib-Induced Immune-Mediated Colitis: A Concerning Adverse Effect of the Novel PI3Kδ/CK1ε Inhibitor.

Novel chemotherapeutic agents are developed to treat recurrent/relapsed lymphoid malignancies. Umbralisib, a novel phosphatidylinositol 3-kinase inhibitor with a selective isoform binding, has shown an improved efficacy and safety profile in clinical trials. Immune-mediated colitis, a frequently observed dose-limiting adverse event of phosphatidylinositol 3-kinase inhibitors, has been mostly observed at supratherapeutic doses in the trials, with grade 1 or 2 diarrhea being the most common adverse event at the therapeutic dose (800 mg PO QD). We present a grade-3 colitis that can be attributed to umbralisib-mediated immune toxicity in a patient with chronic lymphocytic leukemia at the therapeutic dose.

Evaluating the Adoption of Laboratory Practice Guidelines.

CONTEXT.­: To date, the College of American Pathologists (CAP) has developed 17 laboratory practice guidelines (LPGs) including updates. In 2013, the CAP was awarded a 5-year cooperative agreement grant from the United States Centers for Disease Control and Prevention to increase the effectiveness of LPGs. OBJECTIVE.­: To assess the awareness and adoption of 2 CAP LPGs: immunohistochemical (IHC) assay validation and initial workup of acute leukemia. DESIGN.­: Baseline surveys for each LPG were conducted in 2010 and 2015, respectively. To measure the adoption of guideline recommendations and inform future updates, a follow-up study consisting of surveys, telephone interviews, and focus group sessions was conducted in laboratories that indicated they perform IHC testing. A follow-up study for the acute leukemia LPG is planned. RESULTS.­: For the IHC Validation LPG, a total of 1624 survey responses, 40 telephone interviews, and discussions with 5 focus group participants were analyzed. The response rate for the aforementioned 3 modalities was 46%, 13%, and 3%, respectively. All modalities indicated most respondents were aware of the LPG and had adopted most or all of its recommendations. Respondents expressed needs for continued communication, increased specificity, and more prescriptive recommendations when the guideline is updated. CONCLUSIONS.­: While data-driven development of evidence-based LPGs requires significant resources, active data collection to identify gaps and assess adoption contributes to improved laboratory testing practices in support of patient care. The CAP identified sustainable modalities to track metrics and developed multiple tools that should improve guideline development, adoption, and implementation. Of these modalities, written or electronic surveys were the most logistically feasible and had the highest response rate.

Evaluation of Testing of Acute Leukemia Samples: Survey Result From the College of American Pathologists.

CONTEXT: - The classification and prognosis determination in acute leukemia (AL) are complex and it is unclear what testing is being performed in practice. OBJECTIVE: - To survey physicians describing their current practice of test ordering in the diagnosis of AL. DESIGN: - In anticipation of a guideline by the College of American Pathologists (CAP) and the American Society for Hematology on laboratory testing needed for the initial workup of AL, a baseline survey was designed by an expert panel from CAP. Members of professional societies were asked to describe their current practice of test ordering. RESULTS: - Two hundred ninety-four responses were received with 258 respondents analyzed after the first qualifying survey question regarding initial diagnosis of AL. One hundred seventy-six of 249 respondents (70.7%) were board-certified hematopathologists. Flow cytometry and karyotype analysis were routinely performed for acute myeloid leukemia (AML) (99.1% [232 of 234] and 96.2% [225 of 234], respectively) and acute lymphoblastic leukemia (ALL) (98.3% [229 of 233] and 96.6% [225 of 233], respectively). In addition, fluorescence in situ hybridization studies were routinely performed by 81.2% (190 of 234) of respondents for AML and 85.0% (198 of 233) of respondents for ALL; other molecular studies were performed by 78.2% (183) for AML and 54.9% (128) for ALL; immunohistochemistry by 44.9% (105) for AML and 47.6% (111) for ALL; and cytochemistry by 24.8% (58) for AML and 14.2% (33) for ALL. CONCLUSIONS: - While flow cytometry and karyotyping are routinely reported as being performed for the diagnosis of AL, there is marked variation in the reporting of testing patterns for other genetic studies, immunohistochemistry, and cytochemistry.

Multiple Calcifying Pseudoneoplasms of the Neuraxis.

Calcifying pseudoneoplasms of the neuraxis (CAPNONs) are extremely rare tumors that are frequently misdiagnosed and overlooked by clinicians. To date, only 40 intracranial lesions have been reported, and in all instances, they were found as a solitary calcified mass. To our knowledge, the current case report is the first to illustrate the development of multiple intraaxial CAPNONs and shed more light on the origin of these lesions. We discuss the case of a 67-year-old woman who presented with a six-year history of recurrent seizures. Magnetic resonance imaging revealed two similar heterogeneous intracranial masses in the ventral midbrain and left frontal white matter with indications of more aggressive behavior in the supratentorial tumor. The lesion was resected, and histopathological analysis showed tissue containing nodules of chondromyxoid material with a coarsely fibrillar matrix and focal alveolar pattern. Palisading cells were noted around the edges as well as dystrophic calcifications and osseous metaplasia, consistent with CAPNON. Interestingly, the patient had a previous history of multiple brain abscesses and a mycotic aneurysm. At her four-month follow-up visit, the patient remained seizure-free and there were no indications of residual tumor or recurrence. In contrast to previous reports, intracranial CAPNONs may manifest as multiple lesions and clinicians should include these tumors in the differential diagnosis of intra-axial calcified masses. The previous history of brain abscesses raises the suspicion of an abnormal proliferative process following an insult to the brain tissue as the underlying origin of these lesions.

Genomic profiling of high-grade large-cell neuroendocrine carcinoma of the colon.

High-grade neuroendocrine carcinoma (HGNEC) of the colon is a rare and aggressive cancer that has a poor prognosis. Currently no standard treatment exists, and published case series report an overall survival of approximately one year with treatment. Typically patients receive treatment similar to that recommended for small-cell lung cancer, extrapolating from the similarity in cancer biology. Here we report a case of HGNEC of the colon with genomic profiling that identified a KRAS G12D mutation and a PI3K mutation that has not yet been reported in the literature for this tumor type.

Molecular Testing in Anatomic Pathology and Adherence to Guidelines: A College of American Pathologists Q-Probes Study of 2230 Testing Events Reported by 26 Institutions.

CONTEXT: The appropriate and timely performance of molecular testing in anatomic pathology is an indicator of quality. The National Comprehensive Cancer Network (NCCN) publishes a comprehensive treatment guideline that includes recommendations for ancillary testing. OBJECTIVE: To establish benchmarks for rates of adherence to NCCN testing recommendations through a multi-institutional study. DESIGN: Participants in a 2013 Q-Probes study of the College of American Pathologists reported data from molecular testing on anatomic pathology cases, excluding hematolymphoid neoplasms, breast primary carcinomas, and gynecologic cytology. RESULTS: Twenty-six institutions reported data from 2230 molecular testing events. In a retrospective study limited to colon, lung, and melanoma, there was strict adherence to guidelines in a median 71% (10th to 90th percentile range, 33%-90%) and there was at least loose adherence in a median 95% (10th to 90th percentile range, 57%-100%). There was adequate tissue to complete testing in a median 98% (10th to 90th percentile range, 86%-100%); in aggregate the adequacy rate for cell blocks was lower (84%, P < .001). Median test turnaround time was 8 days (10th to 90th percentile range, 4-13 days). In a prospective collection of all organ sites, there was strict adherence to guidelines in a median 53% (10th to 90th percentile range, 20%-71%), and there was at least loose adherence in a median 94% (10th to 90th percentile range, 75%-100%). Adherence to guidelines was higher for lung specimens and in institutions with more multidisciplinary conferences. CONCLUSIONS: This multi-institutional study provides benchmarking data on appropriateness and timeliness of molecular testing in anatomic pathology.

Turnaround time for large or complex specimens in surgical pathology: a College of American Pathologists Q-Probes study of 56 institutions.

CONTEXT: Turnaround time (TAT) for large or complex surgical pathology specimens is an indicator of efficiency in anatomic pathology and may affect coordination of patient care. OBJECTIVE: To establish benchmarks for TAT and to identify practice characteristics that may influence TAT. DESIGN: Participants in a 2012 Q-Probes quality improvement program of the College of American Pathologists retrospectively reviewed all surgical pathology cases from the prior 6 months to identify up to 50 cases coded as Current Procedural Terminology (CPT) code 88307 (excluding biopsies) or 88309. Participants reported the times and dates of accessioning and final sign-out. RESULTS: A total of 56 institutions reported on 2763 large or complex cases, which included 70% with CPT code 88307 and 30% with CPT code 88309. Cases requiring special handling comprised 51.5%, and 48.5% were routine. Among all institutions the median TAT was 2.72 calendar days (10th-90th percentile range, 6.23-1.22 days). Longer TAT occurred in governmental institutions (median, 6.06 versus 2.13 days; P < .001) and in institutions that mandate overnight fixation for some specimen types (median, 3.83 versus 2.07 days; P = .03). Longer TAT was associated with CPT code 88309 (median, 3.99 versus 2.82 days; P < .001), special handling (median, 4.13 versus 1.94 days; P < .001), frozen section (median, 3.38 versus 2.92 days; P < .001), radical cancer resection (P < .001), and malignant cases (P < .001). Turnaround time was not significantly affected by either pathology training programs or routine weekend sign-out. CONCLUSIONS: This study provides benchmark data for TAT in large or complex surgical pathology specimens. Turnaround time was good overall, but the range among participating institutions was wide.

Laboratory compliance with the American Society of Clinical Oncology/College of American Pathologists human epidermal growth factor receptor 2 testing guidelines: a 3-year comparison of validation procedures.

CONTEXT: The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) published guidelines in 2007 regarding testing accuracy, interpretation, and reporting of results for HER2 studies. A 2008 survey identified areas needing improved compliance. OBJECTIVE: To reassess laboratory response to those guidelines following a full accreditation cycle for an updated snapshot of laboratory practices regarding ASCO/CAP guidelines. DESIGN: In 2011, a survey was distributed with the HER2 immunohistochemistry (IHC) proficiency testing program identical to the 2008 survey. RESULTS: Of the 1150 surveys sent, 977 (85.0%) were returned, comparable to the original survey response in 2008 (757 of 907; 83.5%). New participants submitted 124 of 977 (12.7%) surveys. The median laboratory accession rate was 14,788 cases with 211 HER2 tests performed annually. Testing was validated with fluorescence in situ hybridization in 49.1% (443 of 902) of the laboratories; 26.3% (224 of 853) of the laboratories used another IHC assay. The median number of cases to validate fluorescence in situ hybridization (n = 40) and IHC (n = 27) was similar to those in 2008. Ninety-five percent concordance with fluorescence in situ hybridization was achieved by 76.5% (254 of 332) of laboratories for IHC(-) findings and 70.4% (233 of 331) for IHC(+) cases. Ninety-five percent concordance with another IHC assay was achieved by 71.1% (118 of 168) of the laboratories for negative findings and 69.6% (112 of 161) of the laboratories for positive cases. The proportion of laboratories interpreting HER2 IHC using ASCO/CAP guidelines (86.6% [798 of 921] in 2011; 83.8% [605 of 722] in 2008) remains similar. CONCLUSIONS: Although fixation time improvements have been made, assay validation deficiencies still exist. The results of this survey were shared within the CAP, including the Laboratory Accreditation Program and the ASCO/CAP panel revising the HER2 guidelines published in October 2013. The Laboratory Accreditation Program checklist was changed to strengthen HER2 validation practices.

Surgical pathology report defects: a College of American Pathologists Q-Probes study of 73 institutions.

CONTEXT: The rate of surgical pathology report defects is an indicator of quality and it affects clinician satisfaction. OBJECTIVE: To establish benchmarks for defect rates and defect fractions through a large, multi-institutional prospective application of standard taxonomy. DESIGN: Participants in a 2011 Q-Probes study of the College of American Pathologists prospectively reviewed all surgical pathology reports that underwent changes to correct defects and reported details regarding the defects. RESULTS: Seventy-three institutions reported 1688 report defects discovered in 360,218 accessioned cases, for an aggregate defect rate of 4.7 per 1000 cases. Median institutional defect rate was 5.7 per 1000 (10th to 90th percentile range, 13.5-0.9). Defect rates were higher in institutions with a pathology training program (8.5 versus 5.0 per 1000, P = .01) and when a set percentage of cases were reviewed after sign-out (median, 6.7 versus 3.8 per 1000, P = .10). Defect types were as follows: 14.6% misinterpretations, 13.3% misidentifications, 13.7% specimen defects, and 58.4% other report defects. Overall, defects were most often detected by pathologists (47.4%), followed by clinicians (22.0%). Misinterpretations and specimen defects were most often detected by pathologists (73.5% and 82.7% respectively, P < .001), while misidentifications were most often discovered by clinicians (44.6%, P < .001). Misidentification rates were lower when all malignancies were reviewed by a second pathologist before sign-out (0.0 versus 0.6 per 1000, P < .001), and specimen defect rates were lower when intradepartmental review of difficult cases was conducted after sign-out (0.0 versus 0.4 per 1000, P = .02). CONCLUSION: This study provides benchmarking data on report defects and defect fractions using standardized taxonomy.

Immunohistochemistry validation procedures and practices: a College of American Pathologists survey of 727 laboratories.

CONTEXT: The immunohistochemistry (IHC) laboratory represents a dynamic area of surgical pathology with limited practice guidelines. Studies have shown significant interlaboratory variability in results. OBJECTIVE: To establish baseline parameters for IHC validation procedures and practice, and to assess their feasibility of implementation. DESIGN: In September 2010, a questionnaire was distributed by the College of American Pathologists. It was composed of 32 questions relating to nonpredictive assays as well as non-US Food and Drug Administration (non-FDA)-approved, predictive IHC assays other than human epidermal growth factor 2 (HER2/neu). RESULTS: For non-FDA approved, nonpredictive IHC assays, 68% of laboratories had a written validation procedure. Eighty-six percent of laboratories validated the most recently introduced nonpredictive antibody. Seventy-five percent used 21 or fewer total cases for the validation and 40% used weakly or focally positive cases. Forty-six percent of respondents had a written procedure for validation procedures for non-FDA approved, predictive marker IHC assays other than HER2/neu. Seventy-five percent of laboratories validated the most recently introduced predictive antibody other than HER2/neu. Fewer than half used 25 or more cases for the validation, and 47% used weakly or focally positive cases. CONCLUSION: Some laboratories have written validation procedures that appear to build upon HER2/neu testing guidelines. Some laboratories also manage to validate new antibodies according to those standards; however, many do not. There appears to be a need for further validation guideline development for nonpredictive and non-FDA approved predictive antibody IHC assays.

Pathologic diagnostic correlation with breast imaging findings: a College of American Pathologists Q-Probes study of 48 institutions.

CONTEXT: Correlation of radiologic and pathologic findings is important for optimal management of patients with image-guided breast biopsies. OBJECTIVES: To (1) evaluate the rates of radiologic and pathologic correlation in breast needle core biopsies, (2) evaluate laboratory and radiology practices associated with greater correlation rates, and (3) determine the rates at which the lack of radiologic-pathologic correlation is documented in pathology reports. DESIGN: The study was offered and conducted as a College of American Pathologists voluntary Q-Probes program. Participants in this study retrospectively reviewed 30 consecutive, initial, diagnostic needle core biopsy cases performed for abnormal radiologic findings. If 12 months of accessioned cases were reviewed without identifying 30 qualifying cases, participants stopped the retrospective review and included all cases identified. For each case or specimen, the participants provided detailed information about the radiologic and pathologic findings. RESULTS: In aggregate, a radiologic-pathologic correlation was found in 94.9% (1328 of 1399) of the cases reviewed, based on the participants' judgments. Significant differences in the correlation rates existed when cases were discussed at an interdepartmental, multidisciplinary conference (P < .001). No significant differences were found in the correlation rates of the following: whether surgeons or radiologists performed the biopsy, whether cores with calcifications were identified by any method, and whether the laboratory had one or more designated breast pathologists. CONCLUSIONS: Participation in a multidisciplinary breast conference is useful in radiologic-pathologic correlation. Active involvement by pathologists in correlating pathologic and radiologic findings is important.

Impact of neoadjuvant chemoradiation on the tumor burden before liver transplantation for unresectable cholangiocarcinoma.

The very early experience with liver transplantation (LT) for cholangiocarcinoma (CC) was dismal because of the poor survival outcomes and the high recurrence rates. However, LT for CC in conjunction with neoadjuvant chemoradiation recently has shown encouraging results, although the data are extremely limited. At our institution between 2001 and 2008, 22 CC patients underwent protocol orthotopic LT at a median age of 45 years (range = 24-63 years). At a median follow-up of 601.5 days (range = 111-1388 days), the median survival time of the cohort was 3.3 years. The 1-, 2-, and 3-year Kaplan-Meier survival probabilities were 90%, 70%, and 63%, respectively, whereas the historical 5-year survival rates were 0% to 18% for intrahepatic CC and 23% to 26% for extrahepatic CC when patients underwent transplantation without neoadjuvant therapy. These encouraging survival rates for patients with this type of tumor, which is difficult to diagnose and treat, are no less significant when they are compared to the national 1- and 3-year survival rates (86% and 68%, respectively) of patients undergoing deceased donor LT for malignant neoplasms of the liver (as reported by the United Network for Organ Sharing). In our series, disease recurrence was significantly associated with a larger residual tumor [6.3 versus 2.0 cm (mean values), P = 0.008] and with a shorter waiting time for LT after the chemoradiation protocol [18 versus 56 days (mean values), P = 0.04]. Our LT protocol for CC was found to be promising for patients with truly extrahepatic CC and for patients within stages I to IIB of the American Joint Committee on Cancer Staging system (100% survival at a median follow-up of 2.2 years), but the results were notably poor for patients with stage III extrahepatic CC (median survival = 1.2 years). These observations highlight the need for accurate preoperative staging of CC for ideal LT recipient selection and the importance of a low tumor burden and a longer wait after neoadjuvant therapy. More effective chemoradiation regimens for reducing the tumor burden and the appropriate timing of LT after neoadjuvant chemoradiation require further research.