Distinct Nucleoli Research Articles

Primary Pulmonary Follicular Dendritic Cell Neoplasm: A Case Report and Review of the Literature

Follicular dendritic cell tumor (FDCT) is an uncommon neoplasm that typically presents as a slow-growing, painless mass without systemic symptoms. Histologically, FDCT is characterized as a proliferation of spindle to ovoid cells having plump eosinophilic cytoplasm with indistinct borders and nuclei with vesicular or granular chromatin and small distinct nucleoli. The immunohistochemical profile of FDCT includes positive staining for CD21, CD23, CD35, vimentin, fascin, HLA-DR, epithelial membrane antigen, clusterin, and D2-40. Follicular dendritic cell tumor occurs primarily in lymphoid tissue; however, involvement of extranodal sites such as the tonsils, spleen, and gastrointestinal tract has been reported. Lung involvement typically represents metastatic disease with, to our knowledge, only 2 prior cases of extranodal primary FDCT of the lung reported. We report the third case of primary pulmonary FDCT arising in a 64-year-old woman.

Primary pulmonary follicular dendritic cell neoplasm: a case report and review of the literature.

Follicular dendritic cell tumor (FDCT) is an uncommon neoplasm that typically presents as a slow-growing, painless mass without systemic symptoms. Histologically, FDCT is characterized as a proliferation of spindle to ovoid cells having plump eosinophilic cytoplasm with indistinct borders and nuclei with vesicular or granular chromatin and small distinct nucleoli. The immunohistochemical profile of FDCT includes positive staining for CD21, CD23, CD35, vimentin, fascin, HLA-DR, epithelial membrane antigen, clusterin, and D2-40. Follicular dendritic cell tumor occurs primarily in lymphoid tissue; however, involvement of extranodal sites such as the tonsils, spleen, and gastrointestinal tract has been reported. Lung involvement typically represents metastatic disease with, to our knowledge, only 2 prior cases of extranodal primary FDCT of the lung reported. We report the third case of primary pulmonary FDCT arising in a 64-year-old woman.

Acinic cell carcinoma‐papillary cystic variant. Pitfalls of fine needle aspiration diagnosis: study of five cases and review of literature

Acinic cell carcinoma (ACC) accounts for 12-17% of primary salivary gland carcinomas and 3.4% of all salivary gland neoplasms. ACC-papillary cystic variant (PCV) is a distinct subtype with clear-cut and well-defined morphological features as revealed in tissue sections, but it is more difficult to diagnose accurately on fine needle aspiration (FNA). The aim of this article was to discuss the causes of the erroneous interpretation as well as to draw attention of practicing pathologists to this rare and unique variant of ACC. A computerized search of surgical and cytopathology files identified five diagnoses of ACC-PCV that were preceded by an FNA performed in-house with available slides for review. Cytological features were compared to histomorphological features of excisional surgical pathology specimens. Cytomorphological findings from these ACC-PCV cases have varied features that can be broadly divided in two major subtypes: hypocellular cystic specimens containing histiocyte-like vacuolated cells (two cases) and more cellular specimens containing papillary clusters of cells with a polymorphous appearance including granular cells, vacuolated cells and nondescript small cuboidal cells (three cases). Hypocellular, cyst-like specimens pose a diagnostic problem when using FNA, as they can easily be misinterpreted as a benign cyst of the salivary gland. Our review of cases found certain 'red flags' that should prompt pathologists to further investigate the true acinic origin of hypocellular cystic specimens. On close morphological examination, these specimens revealed the presence of tight cellular clusters, distinct cytoplasmic borders, larger nuclei with distinct nucleoli and binucleated cells.

286 ESTABLISHMENT OF PORCINE EMBRYONIC STEM CELL-LIKE CULTURES USING DIFFERENT MEDIA

Porcine embryonic stem cells (pESC) have the potential of becoming an invaluable model for cell-based therapy. However, stable pESC lines are still lacking. We aimed at evaluating various culture media containing growth factors known to support the growth of murine and human ESC for generation of pESC. A total of 186 zona pellucida enclosed (ZPE) and 8 zona pellucida hatched (ZPH) blastocysts were isolated by flushing of sow uteri 5 days post insemination. A total of 122 of the ZPE blastocysts were selected for culture on mouse embryonic fibroblasts (MEF) using either culture of whole blastocyst or immunosurgery. Six types of media were tested: (1) Pig ESC medium [pESCm; DMEM/F10 (1:1), 10% Knockout Serum (KSR), 5% Fetal Bovine Serum and 0.1% leukaemia inhibitory factor (LIF)], (2) pESCm supplemented with 20 ng mL–1 stem cell factor (SCF) (pESCm+SCF), (3) pESCm supplemented with 4 ng mL–1 basic fibroblast growth factor (bFGF; pESCm+bFGF), (4) Human ESC medium (hESCm; Knockout DMEM, 15% KSR and 4 ng mL–1 bFGF), (5) hESCm supplemented with 0.1% LIF (hESCm+LIF) and (6) a commercial LIF containing medium (Resgro; Millipore A/S, Copenhagen, Denmark) used for derivation of murine ESC. At Day 7 of culture, outgrowth colonies (OC) were morphologically examined and attachment rates as well as number of ES-like colonies were noted. ES-like colonies were defined as delineated colonies containing cells with a high nucleo-cytoplasmic ratio and one or two distinct nucleoli. This morphology was verified by nuclear immunocytochemical OCT4-staining (Santa Cruz Biotechnology, Santa Cruz, CA, USA) upon 4% paraformaldehyde fixation. Manual passaging was performed on Day 8 to 10 and RT-PCR was performed on pieces of colonies to evaluate OCT4, Nanog and SOX2 expression. Attachment rates were similar across media groups using whole blastocyst culture and immunosurgery (46 v. 39%, respectively) as were the rates of ES-like OC (80 v. 74%). The highest attachment rates were obtained in pESCm+SCF (60%), hESCm+LIF (55%) and pESCm+bFGF (54%), whereas rates were significantly lower in pESCm (36%), Resgro (33%) and hESCm (22%). High numbers of ES-like colonies were obtained in hESCm (100%) and pESCm+bFGF (100%) though not significantly different from pESCm (89%), hESC+LIF (83%) and pESCm+SCF (66%). Culture in Resgro medium, on the contrary, resulted exclusively in differentiated OC. The maximum number of passages was obtained in pESCm (7 passages) and hESCm (4 passages) after which the colonies started to differentiate into an epithelial-like morphology or became quiescent. RT-PCR analyses showed that most of the ES-like OC were positive for all the pluripotency markers tested, but the passages were, in general, either negative or inconsistently positive for Oct4, Nanog and/or Sox2. In conclusion, supplementation of media with growth factors used for culture of human and murine ESC had a positive effect on the attachment rate of pESC, whereas an effect on the rate of ES-like OC was lacking. The commercial murine ESC medium, Resgro, did not yield ES-like OC at all. Further optimization is needed in order to maintain pluripotency after passage.

Clinical and immunohistochemical evaluation of the vulvar Langerhans cell histiocytosis

We present the case of a woman with diabetes insipidus with subsequent genital and multiorgan Langerhans cell histiocytosis (LCH). A monolateral and slightly infiltrated erythematous plaque of the vulva was observed. Hematoxylin and eosin and immunophenotypic studies were performed. The primary antibodies used were monoclonal antibody to S100, CD1a, CD34, HLA-DR, PCNA, CD45Ro, CD40, and langerin. The histology of the infiltrates revealed a granulomatous reaction pattern, with extensive aggregates of histiocyte proliferation. The histiocytes, morphologically characterized by a pale staining of cytoplasm surrounding a grooved reniform nucleus, sometimes contained small distinct nucleoli. Lymphocytes, eosinophils, macrophages, and both plasma cells and giant cells typically infiltrated the lesions. Cells CD1a+ and S100+ infiltrated the epidermic and were dispersed over the infiltrates as well as in clusters, and around the vessels. A considerable number of CD40-expressing cells were restricted to CD1a+ LCH cells. The specimen contained a high percentage of langerin+ cells in both the dermis and the epidermis. The clinical manifestations of LCH affecting the genital area can be diverse, and in most patients take the form of ulcers or erythematous plaques. Histopathologic examination of the lesion evidences a mixture of Langerhans cell histiocytes (CD1a+, S100+, HLADr+, CD207+, CD 40+), lymphocytes (predominantly helper [CD4] CD 45 Ro+), eosinophils, and macrophages. Each of the cell types produces a "cytokine storm." Many of the cytokines favor recruitment of Langerhans cell progenitors and rescue the Langerhans cell histiocytes from apoptosis.

Interdigitating dendritic cell sarcoma/tumor: a study of 3 cases

To study the pathologic features, diagnosis and differential diagnosis of interdigitating dendritic cell sarcoma (IDCS). The clinical findings, morphologic features and immunophenotype of 3 cases of IDCS were investigated. Gross examination showed that IDCS had a greyish-white to greyish-yellow cut surface. The site of occurrence included lung, spleen (with lymph node metastasis) and lymph node. Histologically, the tumor cells were arranged in nests, fascicles and whorls, with intimate admixture of many lymphocytes and plasma cells. They were oval to spindle in shape and contained pale eosinophilic cytoplasm, oval and sometimes grooved nuclei, small distinct nucleoli and ill-defined cell borders. Immunohistochemical study showed that the tumor cells expressed S-100 protein. IDCS is a rare type of histiocytic and dendritic cell malignancy with distinctive morphologic findings. It needs to be distinguished from follicular dendritic cell sarcoma, inflammatory pseudotumor, Langerhans' cell histiocytosis, malignant melanoma, undifferentiated carcinoma and anaplastic large cell lymphoma. Immunohistochemical staining for S-100 protein is helpful in confirming the diagnosis.

Anaplastic Large Cell Lymphoma in Leukemic Presentation

It is extremely rare that a patient with anaplastic large cell lymphoma (ALCL) demonstrates circulating lymphoma cells. A 10-year-old Japanese boy was presented with high-grade fever and cough. The physical examination revealed marked hepatosplenomegaly with ascites and lymphadenopathy in the cervical and periauricular areas. The white cell count was 26.2x10(9)/L with 95% of abnormal lymphoid cells, which were small to medium-sized with a high nucleus/cytoplasm ratio, basophilic cytoplasm, condensed nuclear chromatins, and 1 or 2 distinct nucleoli, hemoglobin 6.4 g/dL, and platelet 0.9x10(9)/L. A flow cytometric analysis of abnormal cells in both the peripheral blood and bone marrow samples was strongly positive for CD30 on their cell membranes. Karyogram and fluorescent in situ hybridization showed abnormal cells to have a characteristic chromosomal translocation, t(2;5)(p23;q35). Reverse transcriptase-polymerase chain reaction of peripheral blood cell-derived mRNA also indicated the fusion gene product of anaplastic lymphoma kinase and nucleophosmin. Subsequently, the patient was diagnosed to have ALCL with a rare clinical feature of a peripheral leukemic presentation, and his disease revealed to be refractory to chemotherapy. On the basis of the 11 childhood cases of ALCL with leukemic presentation so far published and reviewed herein, the prognosis is very poor.

Inhibition of Apoptosome Activation Protects Injured Motor Neurons from Cell Death

Within the mammalian central nervous system many forms of neurodegenerative injury are regulated via programmed cell death, a highly conserved program of cellular suicide. Programmed cell death is regulated by multiple signaling pathways, which have been identified within mammalian cells, although several lines of evidence suggest that the intrinsic pathway predominantly regulates the death of motor neurons following acute injury in vivo. We have tested this hypothesis by performing facial axotomies on cytochrome c knock-in mice containing a point mutation in the genomic locus of cytochrome c resulting in a lysine to alanine conversion at position 72 of the protein. The introduced mutation inhibits the ability of cytochrome c to induce the formation of the apoptosome, a protein complex that is principally required for the activation of the intrinsic pathway, but does not alter its function in oxidative phosphorylation. Homozygous cytochrome c knock-in mutants displayed a significant enhancement in motor neuron survival following injury when compared with littermate controls, thus establishing the apoptosome as a viable target for protecting motor neurons from neural injury. However, protection of facial motor neurons differs from that previously reported in mice either overexpressing anti-apoptotic or lacking pro-apoptotic members of the Bcl-2 family, which are thought to regulate several aspects of mitochondrial dysfunction including the release of cytochrome c from the mitochondria to the cytoplasm. Therefore, these results directly demonstrate for the first time the influence of the apoptosome on injury-induced neuronal programmed cell death in vivo isolated from upstream Bcl-2 family-mediated effects.

Ossifying Fibromyxoid Tumor of Soft Parts—A Clinicopathologic and Immunohistochemical Study of 104 Cases With Long-term Follow-up and a Critical Review of the Literature

Ossifying fibromyxoid tumor (OFT) is a unique soft tissue tumor of uncertain histogenesis. The majority of reported cases (approximately 220) have pursued a benign clinical course. However, recent literature has emphasized the existence of morphologically atypical and clinically malignant examples of this tumor and proposed guidelines for assessment of biologic potential. In the present study, we evaluated 104 cases of OFT from the Armed Forces Institute of Pathology, accessioned between the years 1970 and 2007. Herein, OFT was strictly defined as a tumor with lobular architecture, predominantly epithelioid cell morphology, a low level of atypia, corded and trabecular growth patterns, moderate amounts of myxocollagenous matrix, and often, focal peripheral metaplastic bone formation. Tumors that lacked conventional morphology were excluded. The exclusion group included cutaneous mixed tumors, low-grade fibromyxoid sarcomas, and extraskeletal osteosarcomas. The OFTs occurred in 64 men and 40 women with a median age of 50 years (range, 21 to 81 y). The tumor size ranged from 0.7 to 17 cm (median, 3 cm). The mitotic rate varied from 0 to 41 mitotic figures per 50 HPFs (median, 2/50 HPFs). Tumor cell nuclei typically contained small, distinct nucleoli, and necrosis was infrequent (11/104). The great majority of tumors (67/71, 94%) were positive for S100 protein, whereas only occasional examples had (focal) positivity for desmin, glial fibrillary acidic protein, and an AE1/AE3 keratin cocktail. Local recurrences were documented in 9 of 41(22%) living patients, usually 10 or more years after primary surgery, but there were no metastases. A mitotic rate of >2 mitotic figures/50 HPFs was a risk factor for local recurrence, but necrosis, tumor size, the presence of satellite nodules, and positive margins were not. When OFT is strictly defined by the criteria noted above, there is potential for local recurrence, but there seems to be little or no risk for metastasis.

Fine‐needle aspiration cytology of Rosai‐Dorfman disease of bone

Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) is a rare, benign self-limiting condition of unknown etiology. Less than a quarter of cases have only extranodal involvement and a few cases of skeletal involvement of Rosai-Dorfman disease without associated lymphadenopathy have been reported in the literature. We herein report cytohistologic findings in a case of sole skeletal Rosai-Dorfman disease in a 51-year-old woman who presented with an expansile, heterogeneous lesion at T11 with cord compression and edema. A CT-guided fine-needle aspiration of T-11 lesion was performed and the sample was processed by ThinPrep technique. The ThinPrep smear showed characteristic features of Rosai-Dorfman disease including hypercellularity with moderate number of histiocytes in a background of lymphocytes, plasma cells, and neutrophils. The histiocytes possessed abundant, pale and vacuolated cytoplasm, rounded nuclei with smooth nuclear membranes, fine chromatin, and distinct nucleoli. The histiocytes showed emperipolesis of lymphocytes and neutrophils. The diagnosis was confirmed by concurrent biopsy with immunhistochemical study. Our case highlighted the role of fine-needle aspiration with ThinPrep technique in the diagnosis of Rosai-Dorfman disease.

Primary cutaneous carcinosarcoma: case report with expanded immunohistochemical analysis

An 83‐year‐old woman presented with a nodular, eroded tumor on the skin between the nose and the upper lip of 18 months’ duration. There were no palpable lymph nodes and no infiltrates on chest radiography. Complete surgical excision showed a tumor measuring 65 × 40 × 30 mm. On histopathologic examination, it was composed of typical basal cell carcinoma (BCC) nodules and large sheets of oval or short spindle cells (Fig. 1a), with vesicular nuclei, distinct nucleoli, moderate pleomorphism, and pronounced mitotic activity (more than 40 mitoses/10 high‐power fields). In parts abutting the upper lip, BCC nodules were found in the muscle layer, but the small salivary glands were uninvolved (Fig. 1b). Immunohistochemical analysis (Table 1) revealed a cytokeratin (CK)‐positive, Ber‐EP4‐positive, and vimentin‐negative BCC component (Fig. 2a), and a vimentin‐positive, CK‐negative sarcomatous component (Fig. 2b). In addition, mesenchymal tumor components were focally positive for smooth muscle actin (SMA). The BCC component showed irregular reaction with CK7, which stained some lobules and parts of individual nests (Fig. 2c). The final diagnosis was primary cutaneous carcinosarcoma. At the last visit, 3 months after operation, no signs of recurrence or metastatic spread were observed. Additional immunohistochemical analyses showed preserved membranous β‐catenin staining in the BCC component, without nuclear reaction in the mesenchymal component. The labeling index (LI) is expressed as the percentage of positive cells, and is calculated from the number of positive tumor cells divided by the total number of tumor cells counted (minimum 300 cells) in the areas with most pronounced immunopositivity. Counting was performed on images taken from microscopic high‐power fields with an Olympus DP70 digital camera (Olympus Corporation, Tokyo, Japan). The program analySYS (Soft Imaging System, Munster, Germany) was used, with the screen grid and the manual touch‐count method. The LI values of Ki‐67 and telomerase reverse transcriptase (hTERT) were higher in the sarcomatous component. hTERT displayed enhanced nucleolar localization and diffuse staining of mitotic cells. Histone deacetylase 1 (HDAC1) was expressed in a smaller percentage of cells than HDAC2, with a higher LI in the sarcomatous component. HDAC2 was the only marker analyzed that stained more cells in the BCC component (Fig. 2d).(a) Basal cell carcinoma (BCC) nodules and diffuse proliferation of sarcomatous cells. (b) Deep peripheral parts of the tumor show BCC nodules infiltrating into the muscle layer, but the small salivary glands are uninvolved. Hematoxylin and eosin; original magnification: (a) ×100; (b) ×40image Immunohistochemical staining in carcinosarcoma Antigen Source Epithelial (BCC) component Mesenchymal component CK (AE1/AE3) Dako* + – EA (Ber‐EP4) Dako + – CK7 Dako + (variable) – EMA Dako – – CEA Dako – – S‐100 Dako – – HMB‐45 Dako – – Vimentin Dako – + Factor VIII‐related Ag Dako – – CD34 Dako – – CD68 Dako – – CD99 Dako – – LCA Dako – – α‐SMA Dako – + (focal) Desmin Dako – – β‐Catenin Santa Cruz† + (membranous) – Ki‐67 (LI) Dako 10% 32% hTERT (LI) Novocastra‡ 22% 41% HDAC1 (LI) Santa Cruz 16% 40% HDAC2 (LI) Santa Cruz 76% 37% CEA, carcinoembryonic antigen; CK, cytokeratin; EA, epithelial antigen; EMA, epithelial membrane antigen; HDAC, histone deacetylase; hTERT, telomerase reverse transcriptase; LCA, leukocyte common antigen; LI, labeling index; SMA, smooth muscle actin. Glostrup, Denmark. Santa Cruz, CA, USA. Newcastle, UK. (a) Cytokeratin (CK) stain reveals epithelial (basal cell carcinoma, BCC) nodules, whereas the large sheet of sarcomatous cells (top left) is unstained. (b) Vimentin‐positive sarcomatous component and negative BCC nodules. (c) Variations of CK7 staining between BCC nodules and inside individual nodules. (d) Histone deacetylase 2 (HDAC2) expression is higher in the BCC component (right) than in the sarcomatous component. Streptavidin–biotin; original magnification: (a) ×12.5; (b, c) ×100; (d) ×400image

Erythema multiforme‐like lesions associated with lesional infiltration of tumor cells occurring with adult T‐cell lymphoma/leukemia

A 66‐year‐old Japanese woman visited our hospital with a complaint of multiple papules on her trunk and extremities. She had a past medical history of appendicitis and blood transfusion 40 years earlier. For the last 10 years, she had noticed multiple, gradually enlarging papulonodular lesions with surrounding erythema on her trunk and extremities. Physical examination revealed multiple, violaceous papules or nodules, less than 10 mm in diameter, with surrounding erythema on her trunk and extremities (Fig. 1). The results of routine laboratory examinations, including blood count, liver function, renal function, serum calcium, and lactate dehydrogenase, were within the normal range. The peripheral blood picture showed a small population of atypical lymphocytes below 1% of the total white blood cells. Human T‐cell lymphotropic virus type I (HTLV‐I) serology was positive. A microscopic examination of a biopsy specimen from a nodule on the abdomen demonstrated diffuse infiltration of large pleomorphic T cells in the upper and middle dermis, although highly atypical lymphocytes, so‐called flower cells, could not be recognized. Infiltrating lymphocytes were positive for CD2, CD3, CD4, CD5, CD7, and CD45, but negative for CD8 and CD20, immunohistologically. Bone marrow biopsy also demonstrated the infiltration of lymphocytes expressing CD2, CD3, CD4, CD5, and CD7, but not CD25. Southern blot analysis of the infiltrating cells in the skin revealed an integration of HTLV‐I proviral DNA in T cells. Clonal T‐cell receptor γ gene rearrangement was detected in skin and bone marrow biopsies. No abnormal mass or bone defect was detected by chest or abdominal computed tomographic scanning, systemic gallium‐67 citrate scintigraphy, or chest radiography. On the basis of these data, the patient was diagnosed with smouldering‐type adult T‐cell lymphoma/leukemia.Clinical features of adult T‐cell lymphoma/leukemia (ATL) skin lesions. Crusted, target‐like, dark‐red plaques on the lower legsimage The patient was started on topical steroid and electron beam radiation therapy (27 Gy/14 days). Five days after the start of irradiation, she noticed multiple patches of edematous erythema appearing on the trunk and extremities (Fig. 2). As it was initially suspected that these newly emerging erythema multiforme or toxic eruptions were caused by irradiation, therapy was interrupted. Anti‐herpes simplex virus antibody was not checked because no typical herpes simplex lesions were noticed. The patient was not taking any systemic drugs. A skin biopsy was taken from a representative lesion on the chest. The pathologic specimen showed epidermotropism, liquefaction degeneration in the basal layer, marked edema, and dense infiltration of mononuclear cells in the upper dermis. Infiltrating cells possessed abundant cytoplasm and large pleomorphic nuclei with distinct nucleoli (Fig. 3). These findings were consistent with the histopathologic findings of erythema multiforme, except for the atypical lymphoid cell infiltration. Immunohistochemical staining demonstrated that the phenotype of the skin‐infiltrating cells was identical to that of the atypical cells in the initial lesions. As the eruptions did not disappear in spite of the interruption of radiation, total skin irradiation was restarted. After completion of therapy, both the erythema multiforme‐like lesions and the initial adult T‐cell lymphoma/leukemia nodules on the trunk and extremities had resolved, leaving brown pigmentation. The patient has been free of any recurrence of skin lesions or systemic symptoms for 6 years after the completion of total skin irradiation.Appearance of erythema multiforme (EM)‐like lesions. Edematous red plaques involving the breastimageMicroscopic examination of a biopsy specimen from (EM)‐like lesions on the chest (hematoxylin and eosin staining). (a) Epidermotropism, liquefaction degeneration in the basal layer, and dense infiltration of mononuclear cells and severe edema in the upper dermis (×100). (b) High‐power magnification revealed that the dermal infiltration included atypical lymphoid cells with abundant cytoplasm, convoluted large nuclei, and distinct nucleoli (×400)image

A Case of CD45-, CD19- Precursor B Cell Acute Lymphoblastic Leukemia with an Atypical Morphology

The differential diagnosis of acute lymphoblastic leukemia (ALL) from other small round blue cell tumors in children is very important for proper treatment, but sometimes difficult. CD45 is expressed on almost all-human leukocytes and not expressed on other small round blue cell tumors. Moreover, CD19 is expressed on all stages of B lineage cells and loss of this antigen is very rare in precursor B-cell ALL. We report a case of ALL with atypical morphology and immunophenotype. A 6-yr-old girl presented with fever and weight loss. Many abnormal cells with variable sized, high nuclearcytoplasmic ratio and distinct nucleoli were counted 23% in bone marrow. The results of immunophenotyping were negative for CD45, CD19, CD10, CD20, CD3, CD5, CD7, CD56/16, CD13, and CD33 and positive for CD22, TdT, and CD34. The immunohistochemical staining of bone marrow biopsies was positive for CD79a, CD10, TdT and CD99. The cytogenetic study showed normal karyotype but amplification of MLL (myeloid/lymphoid or mixed lineage leukemia) gene was suggestive in the fluorescent in situ hybridization. The patient received the standard chemotherapy for acute lymphoblastic leukemia and reached complete remission.

China rose (Hibiscus rosasinensis) petals: a potent natural carotenoid source for goldfish (Carassius auratus L.)

Goldfish (Carassius auratus) are in demand in world markets due to their attractive golden colour. Carotenoids are the primary source of colour in the skin of fish. To optimize the colour in captivity, fish must obtain an adequate level of carotenoids in their feed. With this objective, four natural colour enhancers were tested. A common batch of feed was divided into five equal portions and colour ingredients, spirulina (D-S), china rose petals (D-C), marigold petals (D-M) and Lactobacil, a commercial probiotic (D-L), were added at 5 mg kg−1 to four portions of feed; one portion (D-O) was kept as a control without any additive. A feeding trial was conducted for 8 weeks. Each 70 L aquarium was stocked with 10 fish (average weight 1.6 g) and feed was given at 5% of the body weight. Growth rate, survival, biochemical composition and pigmentation in the skin of fish were measured. Histological studies of gonads were also conducted. Growth of fish in different treatments was significantly different. There was no difference in the proximate composition of the fish at the start of the experiment but after 8 weeks of feeding, fish fed the diet supplemented with china rose petals had a lower moisture content (70.48%) and higher protein (17.7%) and lipid (5.25%) levels than the group fed the control diet. Pigmentation was the highest (4.01 μg g−1) in D-C, followed by D-M (3.16 μg g−1), D-S (2.92 μg g−1) and D-L (2.84 μg g−1) and the lowest (0.24 μg g−1) in D-O. Gonad development of fish fed with the D-C diet was better compared with the gonads of control (D-O) fish, followed by D-M-, D-L- and D-S-fed fish. Gonads of fish, fed D-C, showed well-marked changes in the testis where a large number of seminiferous tubules bound together by means of a thin layer of connective tissue were observed. These tubules were highly convoluted and were separated from each other by thin connective tissue stroma. The intra space contained connective tissue, blood capillaries and interstitial cells. The spermatogonia could be seen as a large spherical cell containing a large central nucleus with a distinct nucleolus. The study shows that the china rose (Hibiscus rosasinensis) petal is a potent natural carotenoid source for goldfish to enhance its colour and also accelerate gonadal development.

Cutaneous Sebaceous Neoplasms With a Focal Glandular Pattern (Seboapocrine Lesions): A Clinicopathological Study of Three Cases

Presented here are three cutaneous sebaceous tumors (one carcinoma and two sebaceomas), each demonstrating a focal glandular pattern representing apocrine differentiation. The patients, two males and one female, each clinically presented with a small solitary nodule or tumor on the scalp. None of the patients had features of Muir-Torre syndrome. Surgical removal of the lesions was performed in all cases. None of the patients developed recurrence or metastasis after surgery (follow-up ranged from 18 to 24 months). The glandular areas represented a minor but significant component of the lesions and appeared as glands of various complexity, mostly as simple round or elongated tubular structures lined by a row of cuboidal to columnar cells with eosinophilic cytoplasm and round nuclei, with or without a distinct nucleolus. Decapitation secretion was evident but not prominent. In both sebaceomas, at least a portion of the glands had a peripheral small-cell layer that appeared similar to the basal/myoepithelial cells of normal eccrine and apocrine ducts. In some glands, the basal/myoepithelial cells seemed to have undergone hyperplasia, resulting in two or more rows of cells that even formed small islands, with an overall appearance reminiscent of basal cell hyperplasia in the prostate, arising in the basal layer of the prostatic glands. The descriptive terms seboapocrine carcinoma or seboapocrine sebaceoma are proposed for such lesions. These tumors may be viewed as rare histopathological variants of sebaceous carcinoma and sebaceoma, with a second type of differentiation along the lines of the folliculosebaceous-apocrine unit.

Development of the pons in human fetuses

Morphometric and histological studies of the pons were performed by light microscopy in 28 cases of externally normal human fetuses ranging from 90 to 246 mm in crown-rump length (CRL) and from 13 to 28 weeks of gestation. The brainstems of fetuses were embedded in celloidin or paraffin, and transverse sections were prepared. The pons was divided into two regions at the most ventral margin of the medial lemniscus at the level of the motor trigeminal nucleus. The relationships between the total dorsoventral length, ventral length, and dorsal length of the pons versus CRL and gestational ages were calculated, and empiric formulas were fitted. It was found that the ventral portion increased in size more rapidly than the dorsal portion. The proportion of the ventral portion in the total dorsoventral length was constitutively higher than that of the dorsal portion in the present range of CRL. In the pontine nuclei, from 235 mm in the CRL, some large cells with rich cytoplasm, pale nuclei, and a distinct nucleolus appeared on the dorsal side of the pyramidal tract. According to Weigert stained preparations, the first myelinated fibers in each motor root of the trigeminal, abducent, and facial nerves were recognized at 130-140 mm in CRL and the medial lemniscus at 230-235 mm.

Primary histiocytic sarcoma arising in the head and neck with predominant spindle cell component

This is the first case report of Histiocytic Sarcoma (HS) with predominant spindle cell component occurring in the head and neck region of a 41-year-old man. The tumor was composed of sheets of large round to oval cells with pleomorphic vesicular nuclei, prominent nucleoli and abundant eosinophilic cytoplasm. Multinucleated forms, numerous mitoses, and tumor necrosis were also noted. Sheets, fascicles, and whorls of spindle cells with spindled to ovoid vesicular nuclei, small to medium-sized distinct nucleoli, and eosinophilic cytoplasm were frequently observed. Immunohistochemical staining in the tumor cells was positive for CD163, CD68, lysozyme, CD45, and NSE. Focal expression of CD4 and S-100 was also noted. Electron microscopy demonstrated an abundance of lysosomes in the cytoplasm of tumor cells. Chromosome study revealed a 57–80 hyperdiploid [7]/46, XY [13] karyotype, including 3 to 4 copies of various chromosomes. The immunohistochemical and ultrastructural findings confirmed the diagnosis of HS.

Triple thymoma with different histologic types

Clinical Summary A 72-year-old man was admitted to our university hospital after screening because three discrete masses in the anterior mediastinum were noted on his chest computed tomographic scans (Figure 1). The patient was symptom free. Results of physical and laboratory examinations, including the serum level of anti–acetylcholine receptor antibodies, were normal. Total thymectomy with removal of the three tumors was performed through a median sternotomy. The largest firm tumor (Tumor A), measuring 40 30 16 mm and adherent to the mediastinal pleura, was found at the right lower portion of the thymus. Far from it, the second tumor (Tumor B), measuring 17 17 12 mm was noted in the right upper portion, and the remaining one (Tumor C), measuring 12 12 8 mm, was detected in the left lobe of the thymus. No additional tumor was disclosed during the operation. The pathologic examinations of the resected specimens revealed that all three tumors were thymomas with histologic types that were different from each other, according to the World Health Organization classification. Tumor A had invaded the capsule of the thymoma, and the histologic finding of a proliferation of epithelial cells with relatively large and vesicular nuclei with distinct nucleoli among a heavy population of lymphocytes was compatible with type B2 thymoma. Tumor B was encapsulated, and the histologic feature was predominant lymphocytic forms with scattered plump and round to oval epithelial cells (type B1). Tumor C was also encapsulated and comprised rich lymphocytes and spindle-shaped epithelial cells without nuclear atypia (type AB). Moreover, a focus of thymic epithelial cell hyperplasia was observed in the resected thymus. No adjuvant therapy was performed, and the patient has been well without recurrence for 7 months after surgery.

Establishment and validation of primary hepatocytes of the African sharptooth catfish (Clarias gariepinus)

In vitro systems such as primary cells and continuous cell lines are gaining momentum in ecotoxicological studies. Cytotoxicity tests with fish cells as well as tests using specific endpoints such as CYP1A induction are valuable in the toxicity assessment of environmental samples. The main objective of this study was to establish and validate the use of primary hepatocytes from the African sharptooth catfish (Clarias gariepinus) as an in vitro toxicity monitoring system. The successful isolation of primary hepatocytes from the sharptooth catfish was achieved using an in situ perfusion method. The primary hepatocytes responded to CYP1A induction, while a continuous Chinese hamster ovary (CHO-K1) cell line showed no activity when exposed to various concentrations of benzo[a]pyrene (B[a]P) (p<0.0001). Cytotoxicity, as measured by the methyl thiazol tetrazolium (MTT) assay, was not observed following a 72 h exposure of the primary hepatocytes and the CHO-K1 cell line to different B[a]P concentrations. However, the hepatocytes were damaged at higher B[a]P concentrations (>10(-6)M) as shown by transmission electron microscopy. This cytotoxicity effect was also confirmed by the trypan blue exclusion assay (TD(50) of 10(-6)M). Differences in the results between the MTT and trypan blue exclusion assays are probably due to mitochondria that are still metabolically active, causing the tetrazolium salt to be dehydrogenated. The internal architecture of normal primary hepatocytes included large quantities of rough endoplasmic reticulum (often in close proximity to the nucleus), mitochondria, aggregates and scattered glycogen, a few lipid droplets and spherical nuclei with distinct nucleoli. The primary catfish hepatocyte cell culture system, expressing CYP1A when exposed to B[a]P, could be used as a biomarker for aromatic hydrocarbon pollutants in aquatic ecosystems of southern and East Africa.

Cytologic findings in malignant myoepithelioma: a case report and review of the literature

BackgroundMyoepithelioma of the breast is a rare tumor and the cytologic features have only been described in one previous report.Case presentationThe present case comprises a 70 year old woman with a mammographic equivocal and ultrasonographic suspicious lesion. The aspirates were cellular and consisted mainly of single spindle or polymorphic, polygonal cells. The nuclei were generally large, ranging from 2 - > 5 × RBC. Most nuclei had a distinct medium-sized nucleolus. The nuclear outlines were irregular with buds and folds. The chromatin was granular. In the background there was abundant granular metachromatic ground substance and some metachromatic stromal fragments. A few mitotic figures were found. The cytologic diagnosis was suspicious for malignancy and a metaplastic carcinoma where only the non-epithelial component had been aspirated, or a non-epithelial lesion, was suggested.Macroscopically the tumor was round, seemingly well circumscribed, firm and with a white cut surface. The lesion consisted of spindled and polygonal cells with distinct pleomorphism. There were 6–9 mitoses per high power field (HPF). The tumor infiltrated in the surrounding fatty tissue. On immunohistochemistry, tumor cells were positive for smooth muscle actin, keratin MNF 116 and vimentin. Desmin and S-100 were negative.Ultrastructurally, there were abundant tonofilaments, including globular filamentous bodies and granulated endocytoplasmic reticulum with many dilated cisterns. The histologic diagnosis was malignant myoepithelioma.ConclusionThe case mirrors completely the WHO definition and the previous cytological and histological descriptions of malignant myoepitheliomas in the literature which describe a spindle cell population with unequivocal nuclear atypia, metachromatic background substance and mitoses.