Masanobu Anami

A novel plasmacytoid dendritic cell line, CAL-1, established from a patient with blastic natural killer cell lymphoma.

Blastic natural killer (NK) cell lymphoma corresponding to CD4+CD56+ malignancies is a novel disease entity, according to the results of clinical, morphologic, and immunologic studies. It is especially noteworthy that this disease likely arises from plasmacytoid dendritic cells (pDCs), described previously as plasmacytoid T-cells, which have an important role in innate and adaptive immunity. However, the exact relationship between the tumor cells and pDCs remains to be elucidated.We encountered a patient with typical blastic NK cell lymphoma, which later converted to leukemic manifestations, and tried to establish a cell line using the leukemic cells.We succeeded in establishment of a novel cell line,CAL-1, which originated from the primary malignant cells.The genetic and phenotypic features of CAL-1 cells bear a similarity to those of pDCs, namely, plasmacytoid morphology at light and electron microscopy; negative results for CD11c and lineage-associated markers of CD3, CD14, CD19, and CD16; positive results for HLA-DR, CD4, CD56, CD45RA, and CD123; and negative results for TCR and IgH gene rearrangements. An interesting finding was that CAL-1 cells change morphologically into the mature DC appearance with many long dendrites after short-term culture in the presence of granulocyte-macrophage colony-stimulating factor and interleukin 3.CAL-1 cells can secrete tumor necrosis factorαbut not interferon α.Thus although they do not share in part phenotypic and functional features with their normal counterparts, CAL-1 cells mostly exhibit a striking pDC phenotype.We describe the first novel pDC cell line of CAL-1.This cell line should open the opportunity for study not only of CD4+CD56+ tumor cells but also of pDCs in vitro.

Primary renal angiosarcoma: A case report and review of the literature

Primary renal angiosarcoma is very rare. To our knowledge, only 15 cases have been reported to date. A 77‐year‐old Japanese man with a unilateral kidney presented with massive hematuria followed by renal failure. A renal tumor was suspected and a left nephrectomy was performed. The histopathological diagnosis was angiosarcoma of the kidney. A hemorrhagic tumor measuring 10 × 5 cm and clotted blood was found in the modularly area. The atypical tumor cells had a sinusoidal and solid appearance, and showed Immunohistochemically positive reactions for some of the endothelial markers. The patient died about 21 months after the nephrectomy and the autopsy revealed massive metastases to the liver and retroperitoneum. One of the differential diagnoses of the case was anglomyolipoma, because the tumor cells were relatively bland in their histological appearance with entrapped fat cells in the pelvic area. Fifteen case reports with titles that included the term ‘hemangiosarcoma/anglosarcoma’, ‘hemangioendothelloma/endothelloma’ or ‘vascular sarcoma’ of the kidney were reviewed and compared to the present case.

SMOOTH AND SKELETAL MUSCLE MYOSINS IN SPINDLE CELL TUMORS OF SOFT TISSUE

Histological localization of myosins of the smooth and skeletal muscles was investigated in comparison with that of myoglobin by immunoperoxidase technique using the antibody against each of them in surgical specimens from spindle cell tumors and tumor‐like lesions of the soft tissue. Skeletal muscle myosin was demonstrated in all of the cases of rhabdomyosarcoma, whereas myoglobin was found in 75% of the examined cases. Smooth muscle myosin was widely distributed not only in the tumor cells of smooth muscle origin such as leiomyosarcoma and angioleiomyoma, but also in the tumor cells showing myofibroblastic differentiation such as malignant fibrous histiocytoma and in the epithelial components of synovial sarcoma. The results showed that skeletal muscle myosin can be regarded as an excellent marker in the diagnosis of rhabdomyosarcoma and that smooth muscle myosin is a useful marker of leiomyosarcoma and leiomyomas, and of tumors with myofibroblastic differentiation.

Cytopathologic features of secondary peripheral ameloblastic carcinoma: A case report

Peripheral ameloblastic carcinoma is an extremely rare odontogenic tumor derived from the remnants of dental lamina and/or mucosal epithelium of the oral mucosa. We present a case of secondary peripheral ameloblastic carcinoma of the mandibular gingiva. The patient was a 71‐year‐old man with gingival swelling and persistent bleeding. Exfoliative cytology revealed cohesive clusters composed of basaloid cells with nuclear atypia and various forms of keratinized cells of dysplastic squamous appearance. Some cell groups had a peripheral palisade. Histology of the biopsy and surgically removed specimens revealed characteristic features resembling squamous cell carcinoma, basal cell carcinoma, and benign follicles of ameloblastoma. These neoplastic structures, as well as proliferation and elongation of the mucosal epithelium, comprised an extensive network. The varied cytopathologic findings may be related to proliferation and transformation of basal cells of the mucosal epithelium toward ameloblastic carcinoma and variable squamous differentiation. Diagn. Cytopathol. 2011;39:354–358.

A case of mucoepidermoid carcinoma with melanin pigmentation manifested in the palate

This paper describes the first documented case of mucoepidermoid carcinoma (MEC) with melanin pigmentation manifested in the palate. Histopathological sections showed a neoplasm composed of epidermoid, mucous-producing and intermediate cells. Numerous large cells contained dark pigmented materials. Fontana Masson staining revealed dendritic melanocytes and melanin granules. HMB-45, Melan A and S-100 protein were all positive for melanocytes. Histopathological examination was not typical for malignant melanoma; the lesion was diagnosed as a low-grade MEC with melanin pigmentation.

Better choice of fixatives provides better histological details of the alveolar-capillary interface

Aims: To evaluate lung disease, pulmonary tissues should be fixed by inflation. However, many histological sections prepared after inflation fixation show wire‐like alveolar septa with capillary collapse. We investigated the reason for this artefact. Methods: To evaluate the effect of fixatives, we used the following commercially available solutions: regular 10% neutral buffered formalin (NBF), 20% NBF, 10% and 5% formalin prepared by diluting the 20% NBF, modified formalin solution as a substitute for 10% NBF, and 10% formalin prepared by diluting the 100% formalin without any buffers. Results: The osmolarity of the fixative was found to be responsible for the collapse artefact. Ten per cent formalin, prepared by diluting 100% formalin, the commercially available substitute for 10% NBF, and 5% formalin prepared by diluting 20% NBF, yielded the best pulmonary tissue morphology, including that of the alveolar‐capillary interface. Conclusions: Pulmonary physicians and pulmonary pathologists should use a suitable fixative solution for obtaining a better pulmonary architecture as well as to preserve the tissue block in optimal condition for future assessment of pulmonary diseases.

Prognosis of thyroid nodules in individuals living in the Zhitomir region of Ukraine.

Objective After the accident at the Chernobyl Nuclear Power Plant (CNPP), the incidence of thyroid cancer increased among children. Recently, a strong relationship between solid thyroid nodules and the incidence of thyroid cancer was shown in atomic bomb survivors. To assess the prognosis of benign thyroid nodules in individuals living in the Zhitomir region of Ukraine, around the CNPP, we conducted a follow-up investigation of screening data from 1991 to 2000 in the Ukraine. Patients and Methods Participants of this study were 160 inhabitants with thyroid nodules (nodule group) and 160 inhabitants without thyroid nodules (normal control group) intially identified by ultrasonography from 1991 to 2000. All participants were aged 0 to 10 years old and lived in the same area at the time of the accident. We performed follow-up screening of participants and assessed thyroid nodules by fine needle aspiration biopsy. Results Among the nodule group participants, the number and size of nodules were significantly increased at the follow-up screening compared with the initial screening. No thyroid nodules were observed among the normal control group participants. The prevalence of thyroid abnormality, especially nodules that could be cancerous (malignant or suspicious by fine needle aspiration biopsy), was 7.5% in the nodule group and 0% in the normal control group (P<0.001). Conclusions Our study indicated that a thyroid nodule in childhood is a prognostic factor associated with an increase in the number and size of nodules in individuals living in the Zhitomir region of Ukraine.