Archives of pathology & laboratory medicine最新文献

Context.—: The characteristic molecular signature for both atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma is amplified sequences derived from chromosome 12q13-15, including MDM2 proto-oncogene (MDM2). As the progression of atypical lipomatous tumor/well-differentiated liposarcoma to the more aggressive dedifferentiated liposarcoma has the potential to adversely affect patient outcomes, the extent of the latter component might be important to evaluate.

Objective.—: To investigate the correlation between clinicopathologic characteristics, including tumor size, modified Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) grade, molecular data, and outcomes in 123 surgically resected MDM2-amplified liposarcomas.

Design.—: Pathology reports and clinical records were reviewed. A log-rank test was used to compare the survival trends, and univariate logistic regression was performed to identify variables associated with adverse events (distant metastasis and/or death), from which the P value was derived to construct a multivariate regression model.

Results.—: In univariate analysis, the largest single dimension of the dedifferentiated component, the percentage of cells with gain of chromosome 12, mitotic count, and the presence of modified FNCLLC grade 3 were associated with adverse events. In multivariate analysis, the largest single dimension of the dedifferentiated component (odds ratio: 1.169; 95% CI: 1.053, 1.299; P = .003), and a higher mitotic count (odds ratio: 1.133; 95% CI: 1.037, 1.237; P = .006) were correlated with adverse events. There was no statistically significant association between current local recurrence status, overall largest tumor dimension, overall tumor volume, MDM2 copy number, or MDM2 to chromosome 12 centromere probe ratio and adverse outcomes.

Conclusions.—: Staging dedifferentiated liposarcoma based on the size of the dedifferentiated component better predicts the outcome.

Context.—: During platelet shortages, many hospitals produce low-dose platelets by splitting a standard platelet unit (>3 × 1011 platelets in the United States) in 2, then providing these low-dose units to patients. While low-dose units were previously found to be effective for prophylactic purposes in patients undergoing chemotherapy in the Prophylactic Platelet Dose (PLADO) trial, their use in actively bleeding patients has not yet been assessed.

Objective.—: To assess the use and safety of low-dose platelets in actively bleeding patients.

Design.—: We performed a retrospective review of cardiac surgery cases receiving platelet units for 18 months at 1 hospital. Two cohorts, those receiving only whole-dose platelets (37 cases) and those receiving only low-dose platelets (38 cases), were compared during the intraoperative and the 24-hour perioperative period. Mean number of platelet transfusions, dose of other blood products, estimated blood loss, bleeding complications in index cases, and all-cause mortality within 30 days of discharge were compared.

Results.—: There was no significant difference in mean number of intraoperative platelet transfusions between the cohorts (1.61 versus 1.53, P = .57). There was no significant increase in the transfusion of other blood products, estimated blood loss, bleeding complications in index cases, or all-cause mortality within 30 days of discharge in the low-dose platelet cohort, apart from a small increase in requirement for fresh frozen plasma in the perioperative period.

Conclusions.—: These results suggest that low-dose platelets are tentatively equivalent to whole-dose platelets in cardiac surgery during shortages, with similar transfusion requirements and clinical outcomes between groups. Future multicenter studies are needed to confirm these findings.

Context.—: The main objectives of the Paris System are to detect high-grade urothelial carcinoma, to standardize morphologic criteria and the cytopathologic report, to reduce the prevalence of the atypia category, and to improve the malignancy risk stratification.

Objective.—: To compare the results and sensitivity of cytologic classification before and after reclassification by the Paris System.

Design.—: Urinary cytology samples from patients with a histologic diagnosis of urothelial carcinoma were reclassified on the basis of the Paris System categories. The diagnoses before reclassification were divided into 5 categories (A, B, C, D, E) and compared with the Paris System (I, II, III, IV, V). Sensitivity was calculated considering cytohistologic agreement in relation to high-grade urothelial carcinoma.

Results.—: A total of 111 urinary cytology samples from patients were analyzed, corresponding to 40 histologic samples; of these, 12 (30%) were high grade and the remaining were low grade. Comparison of the correlated categories showed an increase from 3 (3 of 111; 2.7%) (A) to 31 (31 of 111; 27.9%) (I) in unsatisfactory cases and a decrease from 67 (67 of 111; 60,0%) to 30 (30 of 111; 27.0%) in negative cases, while the atypia category remained unchanged (15 cases [15 of 111; 13.5%]) (C and III). Suspicious cases increased from 5 (5 of 111; 4.5%) (D) to 14 (14 of 111; 12.6%) (IV) and cases of urothelial carcinoma were unchanged (21 cases [21 of 111; 18.9%]) (E and V). Sensitivity was 69% for the previous classification and 90% for the Paris System.

Conclusions.—: The Paris System improved the sensitivity of urinary cytology and the standardization of the unsatisfactory criteria, with an increase of cases in this category and a decrease of cases previously classified as negative among patients with a subsequent histologic diagnosis of urothelial carcinoma.

Context.—: Recently, a new type of antibody-drug conjugate, trastuzumab-deruxtecan (T-DXd), has been approved for the treatment of metastatic breast cancer with low level of human epidermal growth factor receptor 2 (HER2) gene expression. Thereby, eligibility relies on an accurate diagnosis of HER2-low status defined by immunohistochemistry IHC 1+/2+ with no gene amplification.

Objective.—: To assess pathologists' accuracy and training efficacy in the diagnosis of HER2-low.

Design.—: Agreement rates of HER2-low scoring in breast cancer tissue were assessed between expert consensus and real-world pathologists (n = 77 from 14 countries) before and after a specific 4-hour training for HER2-low detection. Two assays were evaluated, the Ventana Pathway 4B5 CDx and the Dako HercepTest (polyclonal). Concordance of the pathologists with consensus score and efficacy of training were measured by Cohen κ, overall rater agreement, and receiver operating characteristic (ROC) curve statistics.

Results.—: In the Ventana 4B5 HER2-low category, baseline agreement rates were >80% but <90%. Negative percentage agreement was improved from 80.6% to 91.1% by training. In the HER2-0 category, positive percentage agreement (74.6%) was the only parameter below the 80% benchmark but was significantly improved to 89.2% after training. Training efficacy was confirmed by ROC curve analysis, which shows improvement for the identification of HER2-0 and HER2-low cases. Finally, in-depth examination of cases with discordant HER2 status disclosed specific issues of HER2-low underscoring and overscoring.

Conclusions.—: The ability of pathologists to achieve acceptable diagnostic accuracy in identifying patients with HER2-low breast cancer could be enhanced by short-term training. Potential routes to improve the quality of HER2-low scoring in clinical practice have been identified.

Context.—: Laboratory testing practices for diagnosis of Clostridioides difficile infection (CDI) have evolved in response to published guidelines, availability of highly sensitive nucleic acid amplification tests (NAATs), perceived problems with the specificity of NAATs, and CDI reporting requirements.

Objective.—: To assess the current state of laboratory practice for diagnostic CDI testing.

Design.—: An optional 8-item supplemental questionnaire was distributed in December 2019 to the 1374 laboratories participating in the College of American Pathologists C difficile Detection (CDF) proficiency testing program challenge CDF-C.

Results.—: Of 1374 CDF-C participants, 1160 (84.4%) responded, predominantly representing laboratories based in the United States (1077 of 1160; 92.8%). The majority reported using a multistep testing algorithm (684 of 1159; 59.0%). Initial testing with a glutamate dehydrogenase and toxin A/B combination test followed by NAAT for discrepant results was the most common testing method (360 of 1146; 31.4%). NAAT alone (299 of 1146; 26.1%) was next, then NAAT followed by an assay that included toxin A/B enzyme immunoassay if NAAT is positive (258 of 1146; 22.5%). Only 5.4% (62 of 1146) reported using toxin A/B immunoassay alone. Most respondents (1093 of 1131; 96.6%) reported rejecting CDI tests on formed stool, but rejection of CDI testing in pediatric patients was uncommon (211 of 1131; 18.7%). Rejection of CDI testing in patients using laxatives was reported more often by US-based respondents (379 of 1054 [36.0%] versus 9 of 77 [11.7%], P < .001).

Conclusions.—: Multistep algorithms for CDI diagnosis are widely used in line with published recommendations. Most respondents reported rejection of formed stool for CDI testing, but few reported rejection of testing in infants and patients taking laxatives, suggesting these may be areas of opportunity for laboratories to pursue in improving CDI testing practices.

Context.—: The Japanese Society of Hepato-Biliary-Pancreatic Surgery guidelines propose a classification scheme that differs from the Union for International Cancer Control (UICC) system, in which the anatomic U-P point is the boundary between intrahepatic cholangiocarcinoma and perihilar cholangiocarcinoma (PCC).

Objective.—: To investigate whether this classification system improves clinicopathologic and genomic differentiation.

Design.—: Fifty-eight PCC cases defined by the UICC system were collected and classified into intrahepatic PCC (IPCC) and extrahepatic PCC (EPCC) categories using U-P point division. They were analyzed by next-generation sequencing using a panel that targeted 425 cancer-related genes.

Results.—: The IPCC group exhibited a significant larger tumor size compared with the EPCC group (4.67 ± 2.44 cm versus 2.50 ± 0.91 cm, P = .002). The mutation frequency of KRAS proto-oncogene, GTPase (KRAS) Q61 was also significantly higher in the IPCC group than in the EPCC group (16.7% versus 0.0%, P = .03). There were no statistically significant differences in other pathologic features or genomic characteristics, including tumor mutation burden and microsatellite instability. Significant differences in gene mutation rates, such as phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA; 0.0% versus 15.8%, P = .01) and tumor protein p53 (TP53; 34.5% versus 63.2%, P = .04), were observed between PCC and adjacent biliary tract cancers.

Conclusions.—: This study offers valuable insight into the clinicopathologic and genomic features of PCC. It is proposed that the U-P point division may have limited potential to refine the characterization of PCC regarding these features, and that the UICC classification system can readily demonstrate the molecular specificity of PCC.

Context.—: It is known that a subset of cases of classic Hodgkin lymphoma (CHL) with B-cell-rich nodules (lymphocyte-rich CHL) exhibits morphologic and immunophenotypic features that overlap with nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), raising diagnostic difficulties that can be resolved in most cases by performing an adequate battery of immunohistochemical studies.

Objective.—: To fully characterize cases of T-cell-rich Hodgkin lymphoma where a specific diagnosis of NLPHL (ie, pattern D) or CHL could not be made even after complete immunophenotypic investigation.

Design.—: The clinical, immunomorphologic, and molecular (when applicable) presentation of 3 cases of T-cell-rich Hodgkin lymphoma was thoroughly investigated.

Results.—: These 3 cases harbored lymphocyte-predominant-like and Hodgkin and Reed-Sternberg-like cells that partially expressed B-cell and CHL markers and were negative for Tiftein-Barr virus-encoded small RNA, in a T-cell-rich background with residual follicular dendritic cell meshworks; 1 case had frequent and the other 2 cases scant/absent eosinophils and plasma cells. Two patients with advanced-stage (III or IV) disease presented with axillary and supraclavicular lymphadenopathy, respectively, and without B symptoms. These patients underwent NLPHL-like therapeutic management with 6 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin hydrochloride [hydroxydaunorubicin], vincristine sulfate [Oncovin], and prednisone) chemotherapy; both are in complete remission 7 years posttherapy. One patient presented with stage I disease involving an internal mammary lymph node without B-symptoms and was treated with surgical excision alone; this patient is also in complete remission 1 year later.

Conclusions.—: These cases illustrate overlapping features of T-cell-rich NLPHL and CHL with neoplastic cells expressing both B-cell program and CHL markers. This underrecognized overlap has not been fully illustrated in the literature, although it portrays a therapeutic challenge. These neoplasms may deserve in-depth investigation in the future that may bring up diagnostic or theragnostic implications.