GFAP-Negative Subcutaneous Sacrococcygeal Extraspinal Ependymoma.

Ependymomas are slowly growing glial tumors derived from the ependymal cells and usually occur in the central nervous system (CNS). Ependymomas rarely occur outside of the CNS and they are called extraspinal ependymomas. In spite of their metastatic potential, extraspinal ependymomas can be misdiagnosed for other benign mass like pilonidal cysts. The diagnosis is confirmed by histopathology and most of the cases are known to show glial fibrillary acidic protein (GFAP), S-100 protein, and keratin (AE1AE3) immunoreactivity. Herein, we present a case of GFAP-negative ependymoma, which presented as asymptomatic subcutaneous tumor of the left buttock and was clinically misdiagnosed as epidermal cyst. Our case indicates that ependymomas cannot be ruled out by lack of GFAP immunoreactivity and an asymptomatic subcutaneous mass could be a malignant tumor like ependymomas, which requires careful examinations.

Large cell transformation mimicking regional lymphomatoid papulosis in a patient with mycosis fungoides.

A 57-year-old Japanese man with tumor-stage mycosis fungoides suddenly presented multiple small papules on the right chest. Histopathology of a biopsy specimen from the papules revealed medium-to-large pleomorphic lymphoid cells throughout the entire dermis but not in the epidermis, and the large cells expressed CD30 antigen. These newly-developed papules underwent spontaneous remission in the following 3 months. We reviewed the reported cases of mycosis fungoides, which showed CD30-positive large cell transformation and those of CD30-positive lymphoproliferative disorders associated with mycosis fungoides.

Syringocystadenocarcinoma Papilliferum in the Perianal Area.

Syringocystadenocarcinoma papilliferum (SCACP) is a very rare cutaneous adnexal neoplasm. SCACP presents histologic variability, and it is difficult to establish the diagnosis from a punch biopsy. SCACP has an overall configuration similar to that of syringocystadenoma papilliferum (SCAP). When we diagnose SCACP, the histologic features of SCAP can be contributing and immunohistochemical staining is useful. Our case shows the histologic variability of SCACP and the pitfalls of a punch biopsy for the diagnosis of SCACP.

A monoclonal antibody established from the immunization of basal cell carcinoma (BCC) tissues reacts to the intercellular space of BCC and hair follicles.

To detail the histogenetic relationship between basal cell carcinoma (BCC) and hair follicles, a monoclonal antibody, coded as MMKB-1 and established from immunization of mice by human basal cell carcinoma (BCC) tissues, was immunohistochemically studied in tissues of BCC and squamous cell carcinoma (SCC) of the skin, as well as in normal human skin tissues. On 1M-NaCl-split normal human skin tissues, it reacted against both the epidermal and the dermal sides of the basement membrane zone (BMZ). This monoclonal antibody reacted to the BMZ and intercellular space (ICS) of the solid, superficial, and fibrosing types of BCC cell nests, but, in SCC tumor cell nests, it reacted exclusively to the BMZ. Immunoelectron microscopic studies revealed that the corresponding antigen of the monoclonal antibody was distributed in the hemidesmosomes and the anchoring fibrils along the BMZ of the normal human skin and the desmosomes of the BCC cell nest. The monoclonal antibody also reacted to the ICS of the lower outer root sheath and hair matrix. We discussed the histogenesis of BCC and hair follicles, referring to the results of the staining patterns of MMKB-1 monoclonal antibody and to other studies suggesting a histogenetic relationship between BCC and hair follicles.

Myeloperoxidase-antineutrophil cytoplasmic antibody-negative microscopic polyangiitis with pulmonary haemorrhage and IgA nephropathy.

AIM: To report a case of a patient with myeloperoxidase-antineutrophil cytoplasmic antibody (ANCA)-negative microscopic polyangiitis (MPA) and IgA nephropathy associated with severe pulmonary haemorrhage. CASE REPORT: A 59-year-old man presented with ANCA-negative systemic vasculitis accompanied by purpura, nephritis and pulmonary haemorrhage. A skin biopsy specimen revealed pandermal leucocytoclastic vasculitis without IgA deposition and a kidney biopsy showed mesangial nephritis with IgA deposition. Considering these findings, the patient was diagnosed as having MPA with IgA nephropathy. DISCUSSION: In most cases, MPA presents with rapidly progressive necrotizing glomerulonephritis and sometimes lung haemorrhage, while IgA nephropathy is less common among MPA cases. As recent research suggested that in MPA immunoglobulin deposition in the kidney may be an exacerbating factor for renal dysfunction and poor prognosis, close observation is required in these cases.

Evaluation of the chemosensitivity of primary cultured malignant melanoma cells using the collagen gel droplet-embedded culture drug sensitivity test.

Malignant melanoma usually shows resistance to a standard chemotherapy regimen. A useful in vitro method to evaluate individual chemosensitivity is required to select effective anti-cancer drugs. This study aimed to establish in vitro tumor response testing for malignant melanoma. We determined the chemosensitivity of primary cultured melanoma cells using the collagen gel droplet-embedded culture drug sensitivity test (CD-DST). Nineteen tests were carried out for 15 cases of malignant melanoma. Primary cultured melanoma cells in collagen gel droplets were exposed to anti-cancer drugs, including cisplatin, adriamycin, dacarbazine, nimustine and vincristine. After a 7-day incubation in a serum-free medium, living melanoma cells in a collagen droplet were detected by image analysis after staining with Neutral red reagent. In vitro drug exposure conditions were determined to reproduce the value of the plasma area under the time-drug concentration curve in vivo. The rate of evaluation of the primary culture of melanoma cells was 78.9% (15/19 tests). The chemosensitivity of cisplatin, adriamycin, dacarbazine, nimustine and vincristine was 15, 62, 0, 0 and 62%, respectively. Dacarbazine was not suitable for CD-DST due to its prodrug characteristics. The CD-DST method was able to evaluate the chemosensitivity of malignant melanoma to anti-cancer drugs in vitro. This method can also be applied to estimate the efficacy of newly developed anti-cancer drugs in vitro.