Twenty cases of H. pylori-related gastric lymphoproliferative disorders including 12 cases of MALT lymphoma (Grade 5 after Wotherspoon, et al), 6 of suspicious of MALT lymphoma (Grade 4), and 2 of active chronic gastritis (Grade 3) were studied. Using the nested PCR method, paraffin-embedded gastric biopsy specimens of these 20 cases were investigated whether or not monoclonal IgH rearrangement could be demonstrated in infiltrating lymphoid cells. Monoclonal IgH rearrangement was recognized in 6 of 12 MALT lymphomas, but in other 14 cases including 6 of MALT lymphomas the monoclonality was not recognized. The result showed the sensitivity was 50% and the specificity was 100% with this method. Follow-up study after eradication of H. pylori was performed on 6 cases of MALT lymphoma which had showed the monoclonality before, using the same method. The monoclonality disappeared in 5 of 6 and histology showed a complete remission. In the remaining one case the monoclonality was yet demonstrated and lymphoma cells were histologically recognized. Thus, this method is very useful to assess not only the histological diagnosis of MALT lymphoma but also the effectiveness after treatment.

Quantification of mRNAs deriving from malignant cells is useful for estimating leukemic states. In this study, we have developed RT-PCR methods using real-time PCR detection system, a LightCycler, for quantification of bcr/abl chimerical genes in peripheral blood and bone marrow of chronic myeloid leukemia patients. Total amounts of RNA extracted were corrected using beta-actin gene as an internal standard. The coefficients of variation of intra-assay variation and inter-assay variation for each gene were within a range of 1.7-26.0% which showed more precise quantification than the competitive PCR method. The coefficients of variation of assay are within a range of 7.7-27.6% in the case of using three samples of normal subjects from blood collecting to quantification of bcr gene. Bcr/abl and WT1 genes could be measured from 10(2) to 10(8) copies and 10 to 10(5) copies with linearity, respectively. Using real-time PCR detection with LightCycler system, 2 x 10(3) K562 cells among 2 x 10(6) total cells demonstrated the bcr/abl gene, while 2 x 10(1) K562 cells among 2 x 10(6) total cells could be detected using the nested PCR method. In tests of seven clinical samples, five samples demonstrated bcr/abl and WT1 genes, while those in two other patients after bone marrow transplantation and a normal subject could not detected. This result suggests that our quantitative method reflect the clinical stages of CML patients.

Recent progress of molecular and cytogenetic techniques has led to remarkable advances in molecular diagnosis of pediatric malignancies, including malignant bone and soft tissue sarcoma (MSTS). Fusion genes, such as EWS-FLI1 and PAX3-FKHR, were cloned at the chromosome breakpoints of t(11;22) and t(2;13) in Ewing's sarcoma and rhabdomyosarcoma, respectively. Minimal residual disease can be detected by reverse transcriptase-polymerase chain reaction using these translocations. These fusion genes contribute to differential diagnosis of pediatric small round cell tumor, which was difficult to diagnose morphologically. Some of these fusion genes, including SYT-SSX in synovial sarcoma and EWS-FLI1 in Ewing sarcoma, have been reported to be associated with prognosis. Recently, genome-wide searches using microarray and single nucleotide polymorphisms have been performed in pediatric malignancies. These advances have led to the increased importance of molecular diagnosis as well as morphological diagnosis. We review here the recent progress of molecular diagnosis in pediatric malignancies.

A 32-year-old man who had previously undergone chemotherapy for testicular seminoma 11 years ago was admitted to our hospital with a pain in the right leg. Computed tomography (CT) and bone scintigraphy revealed splenomegaly and multiple bone disease. Laboratory examination showed thrombocytopenia. The pathologic diagnosis of the resected spleen and the biopsied rib was angiosarcoma. We found no reports of angiosarcoma following previous chemotherapy for testicular cancer. It is unclear whether the angiosarcoma is a secondary neoplasm induced by the chemotherapy or not. However, the patient had a chromosomal aberration of the peripheral lymphocytes. The chemotherapy might also have affected the chromosomal aberration presumably in endothelial progenitor cells causing the development of a secondary neoplasm. To our knowledge, this is the first case of angiosarcoma after chemotherapy for testicular seminoma.

The factors for determining prognosis after lung cancer surgery are curative operation, pathological stage, pathological classification, adjuvant and neoadjuvant therapies, expression of cancer related genes, and concomitant diseases. In particular, pathological stage (especially N stage) is the most influential factor for tumor recurrence, metastasis and survival. The revision of TNM classification by The Union Internationale Contre le Cancer (UICC) in 1997 was well correlated with prognosis. The 5 year survival rates of stage Ia, Ib, IIa, IIb, and IIIa were 67, 57, 55, 39, and 23%, respectively. Neoadjuvant chemotherapy for clinical N 2 disease is expected to improve surgical curativity and survival. Tumor markers including carcinoembryonic antigen (CEA), CYFRA 21-1, and expression of cancer related genes, such as Ki 67, K-ras, bcl-2 and telomerase, are reported to reflect survival after surgery. Smoking and concomitant pulmonary diseases, such as chronic obstructive pulmonary diseases (COPD) and interstitial lung disease affect postoperative patient quality of life (QOL) and survival. We should examine these factors precisely, predict each patient's prognosis and establish an appropriate treatment strategy for each patient.

Retrovirally expressed interleukin-2 gene, granulocyte macrophage-colony stimulating factor gene, herpes simplex virus-thymidine kinase gene and p53 gene in human esophageal cancer cells showed antitumor effects in a nude mice xenotransplant model. We established a clinical protocol of gene therapy for advanced esophageal cancer using the wild type p53 gene with an adenovirus vector. In December of 2000, we began the first tumor suppressor gene therapy trial. Now, this trial, which has 9 patients. There have been no serious adverse event excluding fever and local pain. The feasibility of this treatment appears fairly good in these 9 cases. Furthermore, we developed a new method for transducing genes without a virus vector since a virus vector has several potentially unwanted properties. In vivo electroporation is a useful strategy for cancer gene therapy. Moreover, electric pulse to established solid tumors increases intracellular concentrations of chemotherapeutic agents. Transduction of the wild-type p53 gene by electroporation decreased the amount of nedaplatin required for tumor suppression. Electrochemo-gene therapy is a relatively simple method and can produce a better therapeutic effect.