Diagnostic Assessment of Deep Learning Algorithms for Frozen Tissue Section Analysis in Women with Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Assessing the metastasis status of the sentinel lymph nodes (SLNs) for hematoxylin and eosin–stained frozen tissue sections by pathologists is an essential but tedious and time-consuming task that contributes to accurate breast cancer staging. This study aimed to review a challenge competition (HeLP 2019) for the development of automated solutions for classifying the metastasis status of breast cancer patients. @*Materials and Methods@#A total of 524 digital slides were obtained from frozen SLN sections: 297 (56.7%) from Asan Medical Center (AMC) and 227 (43.4%) from Seoul National University Bundang Hospital (SNUBH), South Korea. The slides were divided into training, development, and validation sets, where the development set comprised slides from both institutions and training and validation set included slides from only AMC and SNUBH, respectively. The algorithms were assessed for area under the receiver operating characteristic curve (AUC) and measurement of the longest metastatic tumor diameter. The final total scores were calculated as the mean of the two metrics, and the three teams with AUC values greater than 0.500 were selected for review and analysis in this study. @*Results@#The top three teams showed AUC values of 0.891, 0.809, and 0.736 and major axis prediction scores of 0.525, 0.459, and 0.387 for the validation set. The major factor that lowered the diagnostic accuracy was micro-metastasis. @*Conclusion@#In this challenge competition, accurate deep learning algorithms were developed that can be helpful for making a diagnosis on intraoperative SLN biopsy. The clinical utility of this approach was evaluated by including an external validation set from SNUBH.

Anaphylactic Transfusion Reaction in a Patient with Anhaptoglobinemia: The First Case in Korea

Anaphylactic transfusion reactions are rare complications of blood transfusions. Anhaptoglobinemia, a condition that has high incidence in Asia, can cause allergic transfusion reactions or anaphylaxis in severe cases. A 50-yr-old Korean woman was diagnosed with relapsed acute promyelocytic leukemia. She developed thrombocytopenia during chemotherapy and an anaphylactic transfusion reaction on the 4th and 5th platelet transfusions immediately after the transfusion of the platelet concentrates was initiated. Blood analysis showed no detectable serum haptoglobin. We examined her genetic phenotype and detected anhaptoglobinemia, which occurs because of an allelic deletion in the Hp gene cluster. The presence of an antibody against haptoglobin was detected by performing ELISA. To prevent anaphylactic reactions, apheresis platelets were transfused after washing. Consequently, anaphylactic transfusion reactions did not develop. Here, we report the first case of anhaptoglobinemia causing anaphylactic transfusion reaction in Korea.

Analysis of the Patients with Indeterminate Results by Anti-HIV Western Blot Assay: Experience of a University Hospital During Recent 5 Years in Korea / 임상검사와정도관리

BACKGROUND: Interpretation of indeterminate results by anti-HIV Western blot assay, which is currently used as a confirmatory test for HIV infection, can be usually difficult. We analyzed outcomes of the patients with indeterminate results by anti-HIV Western blot. METHODS: Medical records of patients, who were indeterminate by the anti-HIV Western blot assay in a university hospital during recent 5 years, were retrospectively reviewed. HIV screening test was performed by chemiluminescent immunoassay autoanalyzer (Abbot Laboratories, USA) with HIV Ag/Ab Combo kits. Confirmatory Western blot assay for the positive samples by HIV screening test was committed to the Korean National Institute of Health. RESULTS: A total of 202,639 specimens were tested for HIV screening during the period, and 644 (0.32%) sera showed positive results. Among these, 46 (7.1%) cases were indeterminate by the Western blot, which were from 20 patients, and 13 of them converted to be anti-HIV positive, and 3 were lost to follow-up. Another four patients were turned out to be negative for HIV infection, including two neonates from HIV-positive mothers receiving antiviral treatment during pregnancy. CONCLUSIONS: Most of the patients who showed Western blot-indeterminate results converted to HIV positive after follow-up. Thus, careful monitoring of patients with indeterminate Western blot results should be essential.

Subcutaneous Phaeohyphomycosis Caused by Phaeoacremonium Species in a Kidney Transplant Patient: The First Case in Korea / 대한진단검사의학회지

Phaeohyphomycosis is a subcutaneous infection caused by dark pigmented fungi, including fungi of the species Phaeoacremonium, Alternaria, Exophiala, and Pyrenochaeta. In August 2005, a 54-yr-old man who had received a renal transplant 5 yr ago was admitted to our hospital with a subcutaneous mass on the third finger of the right hand; the mass had been present for several months. He had been receiving immunosuppressive agents for several years. He underwent excision of the mass, which was followed by aspiration of the wound for bacterial and fungal cultures. Many fungal hyphae were observed on the histology slide treated with periodic acid-Schiff stain. A few white waxy colonies with a woolly texture grew on the Sabouraud dextrose agar at 30degrees C and changed to dark brown in color. Nucleotide sequencing of internal transcribed spacer regions revealed 100% homology to the Phaeoacremonium aleophilum anamorph and Togninia minima teleomorph (514 bp/514 bp). The patient completely recovered after wide surgical excision. Here, we report the first case of phaeohyphomycosis caused by Phaeoacremonium species in a kidney transplant patient in Korea.

Evaluation of an Automated Coagulation Analyzer Coapresta 2000

BACKGROUND: The Coapresta 2000 (Sekisui Medical CO., LTD, Japan) is a fully automated random-access multiparameter hemostasis coagulation analyzer, which is equipped with a photo-optical clot detection unit and a cap-piercing system. It is able to perform clotting time assays as well as colorimetric assays (synthetic substrate method and latex turbidimetric method). In this study, we evaluated the analytical performance of the Coapresta 2000 for coagulation test items and compared with that of the ACL-TOP (Instrumentation Laboratory, Lexingtion, MA, USA) analyzer, which is currently used for routine coagulation test items in our hospital. METHODS: The Coapresta 2000 was evaluated with respect to its technical characteristics in the determination of 8 routine coagulation test items: prothrombin time, activated partial thromboplastin time, fibrinogen, fibrin-degradation product (FDP) antithrombin III, D-dimer, factors VIII and IX. Analyse-it (Analyse-it Software Ltd, UK) and SigmaStat (Systat Software, Inc., USA) were used for statistical analysis between items on the Coapresta 2000 and the ACL-TOP analyzer. RESULTS: The intra-assay and inter-assay coefficients of variation (CV) were below 5% for both groups of samples having values within the reference interval and outside the reference interval. Significant interference was observed with hemolytic and icteric samples. Carryover was not detected. The results obtained by Coapresta 2000 were well correlated with those obtained by the ACL-TOP analyzer (r2 in the range from 0.781 to 0.969). CONCLUSIONS: We concluded that Coapresta 2000 analyzer was well correlated with ACL-TOP analyzer for the routine coagulation test items tested.

Development of Cryopreserved Red Blood Cell Panels for Verifying ABO and D Blood Grouping Reagents / 대한수혈학회지

BACKGROUND: ABO blood grouping reagent verification is essential to ascertain safe blood transfusions. However, the research use of donated blood products has been hampered in Korea by the blood transfusion law and management policies. In this study, we developed cryopreserved red blood cell (RBC) panels utilizing the high glycerol method to verify the ABO and D blood grouping reagents. In addition, we evaluated the stability of ABO and D antigenicity. METHODS: Fresh blood was frozen by the high glycerol method, aliquoted and cryopreserved in 2 mL cryotubes. Twenty-four vials of bloods with types A (n=5), B (n=5), AB (n=4) and O (n=10) for ABO RBC panels, and eleven vials of blood types D positive (n=5), D negative (n=5) and D weak (n=1) for D RBC panels were established. Potency, avidity and specificity tests were carried out with four different commercial ABO and D blood grouping reagents. RESULTS: The potency of cryopreserved RBCs after thawing showed no statistical difference compared with pre-freezing RBCs. Avidity time measurements were 5 seconds in ABO blood and 20 seconds in D positive blood. Specificity test uniformly showed 100% specificity. When thawed RBCs were stored at 4degrees C for 7 days, the potency test measured at intervals of 2 days showed no variation. CONCLUSION: Cryopreserved RBC panels produced by the high glycerol method showed excellent results in stability test with reagents produced by manufacturers in Korea. Therefore, these panels can be utilized as a reliable method of verifying blood grouping reagents.