Clinical relevance of CD157 for rapid and cost-effective simultaneous evaluation of PNH granulocytes and monocytes by flow cytometry.

INTRODUCTION: CD157 has been reported as a potentially useful marker for paroxysmal nocturnal hemoglobinuria (PNH) testing by flow cytometry (FCM). METHODS: We determined the performance characteristics of a CD157-based five-color assay and compared results from patient analysis with results obtained with a previously validated CD14/CD24-based six-color protocol. RESULTS: Coefficient of variation (CV) for intra-/interassay precision analysis of granulocytes ranged from 0.88/0.09% to 3.02/3.71% and from 0.20/0.08% to 8.83/4.04% for the five- and six-color protocol, respectively. For monocyte, CV ranged from 0.42/0.49% to 8.13/4.80% for the five-color protocol and from 0.28/0.70% to 5.41/3.19% for the six-color protocol within various PNH clones. Coefficient of determination (r(2) ) for linear regression analysis of PNH clones ranging from 0.3 to 99.8% was >0.99 in all cases, Wilcoxon ranks test showed no statistically significant differences (P > 0.05), and Bland-Altman analysis demonstrated agreement with mean bias ranging from -0.02 to 0.38. CONCLUSION: Our results confirm very good performance characteristics for both intra- and interassay precision analyses, excellent correlation, and agreement between approaches. In agreement with recently published data, our experience supports the clinical relevance of CD157 for a rapid and cost-effective simultaneous evaluation of PNH leukocytes by flow cytometry.

Evaluation and comparison of different approaches for the detection of PNH clones by flow cytometry following the ICCS guidelines.

BACKGROUND: Comparison between consensual approaches for the detection of paroxysmal nocturnal hemoglobinuria (PNH) clones by flow cytometry (FCM) following the international clinical cytometry society (ICCS) guidelines has not been widely reported. METHODS: We determined the performance characteristics of 4, 5, and 6-color protocols for white blood cell (WBC) and one and two-color protocols for red blood cell (RBC) evaluation for different PNH target clones and compared results from PNH patient analysis. RESULTS: Coefficient of variation (CV) for precision/reproducibility analysis ranged from 0.01%/0.12% to 2.56%/ 3.59% for granulocytes, from 0.07%/0.08% to 3.87%/11.61% for monocytes and from 0.4%/1.02% to 6.53%/ 5.1% for RBCs within different approaches and target PNH clones. Comparison of individual protocols revealed excellent correlation (r = 0.99), Wilcoxon rank tests found no statistically significant differences (p > 0.05), Bland-Altman analysis proved agreement for all PNH clones (mean bias ranging from 0.02 to 2.2). CONCLUSIONS: Our results confirm good intralaboratory characteristics for precision and reproducibility analysis, excellent correlation and agreement between approaches underlining the primary role of optimally selected glycophosphatidylinositol (GPI)-specific reagents and secondary role of number, type of gating reagents and gating strategy.

[Common, standardized and recommended approaches in the diagnosis and monitoring of paroxysmal nocturnal haemoglobinuria using flow cytometry]. / Bezné, standardizované a doporucené postupy v diagnostice a monitorování paroxysmální nocní hemoglobinurie prutokovou cytometrií

Paroxysmal nocturnal hemoglobinuria is an acquired clonal disease characterized by proliferation of stem cells, deficient of proteins linked to the membrane via glycophosphatidylinositol (GPI) anchors. PNH cell characterization by flow cytometry was introduced in 1986, since 1996 is considered as method of choice for PNH diagnosis. Flow cytometry PNH analysis is nowadays crucial for disease monitoring in terms of progression, regression, remission or response to therapy and screening for small PNH clones (< 1.0%) in patients with aplastic anemia or myelodysplastic syndrome. Flow cytometry is unfortunately still poorly standardized, there is a variety of different methodological approaches for PNH evaluation and results from external quality assurances schemes reveal heterogeneous results. The aim of this work is to review the applicability of flow cytometry for the diagnosis and monitoring of PNH with respect to our experience and in the context of the recent trends and guidelines for PNH evaluation by flow cytometry.

Comparison of three single platform methods for CD34+ hematopoietic stem cell enumeration by flow cytometry.

In the present study, we compared three single platform methods for CD34+ hematopoietic stem cell (HSC) enumeration by flow cytometry. For this purpose, we analyzed the performance characteristics and results obtained from different HSC sources. Interlaboratory coefficients of variation (CV) for precision/reproducibility analysis varied from 4.0% to 6.7% / 6.7% to 9.2% for the low and 3.2% to 4.1% / 4.3% to 6.7%, respectively, for the high stem cell control. Correlation between methods ranged from 0.92% to 0.99%; Wilcoxon test showed no significant differences (p > 0.05); Bland-Altman analysis confirmed good agreement between assays (mean bias ranging from -0.48 to 6.91). Our results demonstrate very good intralaboratory correlation and agreement between methods, confirm the major impact of single platform strategy for accurate and reproducible HSC enumeration and suggest that high interlaboratory variability could be influenced by incorrect performance of validated methods.

Gemcitabine and carboplatin treatment in patients with relapsing ovarian cancer.

Despite progress in primary treatment of patients with advanced ovarian cancer, the majority develop recurrence of the disease. A platinum salt treatment, either as monotherapy or in combination with another cytostatic agent, is indicated for patients who have relapsed 6 or more months after primary treatment and thus have platinum-sensitive relapse. Because repeated use of paclitaxel treatment may lead to substantial neurotoxicity, the combination of gemcitabine with carboplatin represents a suitable treatment option, which is widely used in common clinical practice in the Czech Republic and Slovakia. This non-interventional, prospective study observed the effectiveness and tolerability of second-line treatment with gemcitabine and carboplatin in patients with platinum-sensitive relapse of ovarian cancer in routine clinical practice. The primary endpoint was to evaluate the survival and secondary endpoints were to evaluate time to disease progression, objective tumor response rate, and treatment toxicity. Patients were enrolled to planned second-line treatment with gemcitabine and carboplatin (gemcitabine 1000 mg/m2 and carboplatin AUC 5 on Day 1, and gemcitabine 1000 mg/m2 on Day 8 of a 21-day cycle) for platinum-sensitive relapse of ovarian cancer as a part of routine clinical practice and followed for 12 months. The events (death, tumor progression), tumor response, and maximal grades of toxicity were recorded according to common clinical practice. Survival time (using Kaplan-Meier analysis) and objective tumor response rate were calculated using data forms, and a subgroup analysis was performed using log rank tests for time-to-event endpoints; p-values were also calculated. Response rates were calculated for the whole population; for the subgroups, the Fisher's exact test was performed and only p-values were calculated. Between January 2004 and June 2005, 53 patients were enrolled in the study. The median age was 57 years and 96% of patients had an Eastern Cooperative Oncology Group Performance Status (ECOG-PS) of 0 and 1 at baseline. Approximately 91% of patients were originally diagnosed with stage III or IV; 60% of patients had disease free intervals (DFIs) of 12 or more months from previous therapy, and the additional 40% less than 12 months. The 1-year survival rate was 83%. Median survival time was not determined within the 12-month period following the start of the treatment study due to the limited duration of follow-up. Objective tumour response rate was 67.3%. Most common reasons for discontinuation of therapy were "Planned treatment completed" (53%) and "Tumor progression" (11%). Most common toxicities were leukopenia, anaemia, neutropenia, and thrombocytopenia; grades 3 and 4 of these toxicity types did not exceed 30%. Febrile neutropenia was recorded in two patients. Most common non-haematological toxicities were nausea and vomiting, fatigue, and neuropathy; grades 3 and 4 of these were below 6%. Results on time to disease progression are not published due to inconsistent statistical analysis of reported data. Based on this observation from routine clinical practice, which corresponds with previously published results from controlled clinical trials, the gemcitabine and carboplatin combination seems to be a suitable therapeutic option for patients with platinum-sensitive relapse of ovarian cancer.

[Perivascular epithelioid cell tumor (PEComa) of the liver: a case report and review of the literature]. / Perivascular epithelioid cell tumor (PEComa) pecene: popis prípadu a prehl'ad literatúry.

Perivascular epithelioid cell tumor (PEComa) is rare entity and has been described only recently. By immunohistochemistry and genetics it belongs to the family of tumours which comprises angiomyolipoma, clear cell "sugar" tumor of lung, lymphangioleiomyomatosis and clear cell myomelanotic tumor of ligamentum falciforme/teres hepatis. We describe an unusual case of hepatic PEComa arising in a 55-year-old woman with previous history of glioblastoma. Histologically the tumor grew in expansive way, and was composed of clear and eosinophilic epithelioid cels, without vascular or lipomatous component characteristic of angiomyolipoma. There was mild nuclear pleomorphism, sporadic mitotic activity and haemorrhage without necrosis. On immunohistochemistry, the tumor was HMB-45+50, Melan-A and smooth muscle actin positive. Tyrosinase, S-100 protein, cytokeratin coctail, EMA, vimentin, muscle specific actin, CD10, TTF-1, hepatocyte, desmin and cyclin D1 were negative. Sporadic nuclear p53 positivity was seen. The main differential diagnosis of hepatic PEComa includes clear cell variant of liver cell adenoma and hepatocellular carcinoma, metastases of various clear cell carcinomas and metastasis of malignant melanoma. In respect of uncertain biologic potential of PEComa, long term follow up is indicated.