Evaluation of two semi-supervised learning methods and their combination for automatic classification of bone marrow cells.

Differential bone marrow (BM) cell counting is an important test for the diagnosis of various hematological diseases. However, it is difficult to accurately classify BM cells due to non-uniformity and the lack of reproducibility of differential counting. Therefore, automatic classification systems have been developed in which deep learning is used. These systems requires large and accurately labeled datasets for training. To overcome this, we used semi-supervised learning (SSL), in which learning proceeds while labeling. We used three methods: self-training (ST), active learning (AL), and a combination of these methods, and attempted to automatically classify 16 types of BM cell images. ST involves data verification, as in AL, before adding them to the training dataset (confirmed self-training: CST). After 25 rounds of CST, AL, and CST + AL, the initial number of training data increased from 425 to 40,518; 3682; and 47,843, respectively. Accuracies for the test data of 50 images for each cell type were 0.944, 0.941, and 0.976, respectively. Data added with CST or AL showed some imbalances between classes, while CST + AL exhibited fewer imbalances. We suggest that CST + AL, when combined with two SSL methods, is efficient in increasing training data for the development of automatic BM cells classification systems.

[A Case of Long-Term Survival of a Patient with Gastric Cancer with Synchronous Liver Metastasis and Portal Vein Thrombus after Multidisciplinary Treatment].

A 77-year-old man was diagnosed with gastric cancer with synchronous single liver metastasis and portal vein thrombus. His HER2 immunohistochemistry tumor score was 3+; therefore, we administered trastuzumab plus capecitabine plus cisplatin. After 2 courses of chemotherapy, we observed disappearance of the portal vein thrombus and tumor reduction as a partial response, according to the RECIST guidelines. We performed distal gastrectomy and right lobectomy; the therapeutic grades of the primary and metastatic tumors were 1a and 2, respectively. We administered postoperative chemotherapy, and no recurrent lesions have appeared 2 years after surgery. Multidisciplinary treatment for gastric cancer with liver metastasis might be a feasible and useful strategy.

[Transvesical Removal of Seminal Vesicle Cystadenoma].

Primary tumors of the seminal vesicles are extremely rare. There have been 25 reports of this tumor from overseas and most cases are cystadenoma. We report a case of seminal vesicle cystadenoma in a 70-year-old man who presented with lower abdominal pain and urinary frequency. A digital rectal examination detected a projecting and hard mass in the right side of the prostate. Magnetic resonance imaging (MRI) showed a 15 cm multiple cystic mass continuous with the right seminal vesicle. A transrectal needle biopsy revealed benign tissue. The tumor was resected using an open transvesical approach that enabled full exposure of the seminal vesicle without damaging the nerves and blood supply of the bladder. Pathology was consistent with a benign seminal vesicle cystadenoma. We describe the natural history, pathology,and surgical approach in this case.

[Imatinib mesylate plus G-CSF therapy for chronic myelogenous leukemia in the blastic crisis].

Imatinib mesylate (imatinib) has shown significant effects in patients with chronic myelogenous leukemia. However, hematological toxicity often occurs and requires dosage reduction or discontinuation of imatinib treatment. A patient with chronic myelogenous leukemia in the blastic crisis received granulocyte-colony stimulating factor (G-CSF) simultaneously with imatinib. The patient was continuously treated with imatinib and G-CSF and achieved remission without any severe infection or neutropenia. There are a few reports on the efficacy of combined therapy with G-CSF and imatinib; however, the results in our case are rare suggesting that the use of G-CSF is effective for preventing severe infection. G-CSF enables continuous treatment with high-dose imatinib.

[Prognostic efficacy for measurement of real-time quantitative PCR-based major bcr/abl mRNA in patients with Philadelphia chromosome-positive leukemia].

Evaluation of minimal residual disease (MRD) provides prognostic information on various hematological malignancies. We describe here the prognostic efficacy of real-time quantitative polymerase chain reaction (RQ-PCR)-based analysis of major bcr/abl mRNA in cases of Philadelphia chromosome-positive leukemia (Ph-leukemia). Twenty-one patients with Ph-leukemia were enrolled as subjects to determine the usefulness of RQ-PCR-based measurement of bcr-abl/abl ratios. Imatinib mesylate (imatinib) was administered to seven of the 21 patients before allogeneic stem cell transplantation (SCT). Hematological relapse or failure of treatment with SCT was observed in 2 of those patients who showed bcr-abl/abl ratios of more than 0.002%, and 5 of the 7 patients showed both RQ-PCR and RT-PCR negativity immediately after SCT. All of the 5 patients who did not receive imatinib before allogeneic SCT showed RQ-PCR negativity immediately after SCT, but the results of RT-PCR were positive in 3 patients at the same time points, and those became negative after donor lymphocyte infusion or the appearance of graft-versus-host disease. Administration of imatinib before SCT was thought to induce an early remission. On the other hand, 8 patients who received imatinib without SCT showed a remarkable decrease in bcr-abl/abl ratios. The ratio gradually rose in one patient with Ph+ALL, enabling prediction of the hematological relapse preceding detection by fluorescence in situ hybridization (FISH) analysis. Standardization of RQ-PCR analysis of bcr-abl mRNA will help to predict early hematological relapse in patients with MRD. In conclusion, it is thought that measurement of RQ-PCR-based major bcr/abl mRNA in patients who were given imatinib and were treated with SCT is useful for the evaluation of MRD and in deciding additional treatment.