1,720,979 research outputs found
Hyaline bodies in Kaposi's sarcoma: an immunocytochemical and ultrastructural study
No full textThe nature of hyaline bodies (HB) in Kaposi's sarcoma (KS) has been investigated by electron microscopy (EM) and immunohistochemical methods. Paraffin sections from 45 cases of KS selected on the basis of their high content of HB were challenged with antisera against factor VIIIR:Ag, carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), alpha 1-antitrypsin (A1AT), fibrinogen, hemoglobin, alpha-actin and lysozyme. HB showed positivity for all the antibodies except for the last two. By EM, HB showed features consistent with red blood cell, fibrin and platelet phagocytosis. Therefore, HB in KS are considered to be the expression of an indiscriminate process of phagocytosis which involves not only erythrocytes and platelets, but also other substances such as fibrinogen, factor VIIIR:Ag, A1AT, CEA and AFP.The nature of hyaline bodies (HB) in Kaposi's sarcoma (KS) has been investigated by electron microscopy (EM) and immunohistochemical methods. Paraffin sections from 45 cases of KS selected on the basis of their high content of HB were challenged with antisera against factor VIIIR:Ag, carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), alpha 1-antitrypsin (A1AT), fibrinogen, hemoglobin, alpha-actin and lysozyme. HB showed positivity for all the antibodies except for the last two. By EM, HB showed features consistent with red blood cell, fibrin and platelet phagocytosis. Therefore, HB in KS are considered to be the expression of an indiscriminate process of phagocytosis which involves not only erythrocytes and platelets, but also other substances such as fibrinogen, factor VIIIR:Ag, A1AT, CEA and AFP
Un Infrequente caso di "spindle cell tumor" a localizzazione splenica primaria in un cane: rilievi citologici ed istopatologici, osservazioni istochimiche ed immunoistochimiche
Full text linkTutti i tumori fusocellulari derivano
verosimilmente da una unica cellula staminale
mesenchimale pluripotente. Macroscopicamente e
microscopicamente i tumori delle cellule
muscolari lisce e i tumori del tessuto connettivo
fibroso, si presentano morfologicamente simili.
Abbiamo ritenuto
interessante riferire su un cane meticcio, maschio,
di quattro anni sottoposto ad eutanasia dopo aver
mostrato letargia, anoressia e perdita di peso. Alla
necroscopia si osservava una voluminosa
neoformazione splenica di colore biancastro, dura
e di consistenza fibrosa. Il fegato si presentava
notevolmente aumentato di volume con numerose
neoformazioni di piccole e medie dimensioni.
Diversi campioni appartenenti agli organi
sopramenzionati, venivano sottoposti ad una
prima osservazione citologica. Parte di questi,
dopo fissazione in formalina venivano inclusi in
paraffina. Sezioni di 3-5 μ erano sottoposte a
colorazioni ordinarie e speciali (H. E., tricromica
di Mallory Azan e Van Gieson). Si eseguivano
prove immunoistochimiche utilizzando il seguente
algoritmo anticorpale: anti pan-citocheratine, anti
vimentina, anti fattore VIII, anti-αactina L, anti
desmina, anti CD 15, anti S-100.
La
neoplasia, altamente infiltrante, era costituita da
ampi fasci intrecciati di cellule allungate
fusiformi, fibroblastosimili, a moderato indice
mitotico, disposte in maniera ordinata, a spina di
pesce. Esse risultavano positive alla vimentina e
alla αactina L e negative alla desmina. Dette
caratteristiche ci consentivano di formulare
diagnosi di fibrosarcoma, neoplasia a infrequente
localizzazione splenica primaria, e di identificare
come metastasi della stessa, le neoformazioni
riscontrare a livello epatico
Neuron-specific enolase (gamma enolase, gamma-gamma dimer) expression in Hodgkin's disease and large cell lymphomas
No full textBackground. The presence of gamma-enolase, gamma gamma dimer, or neuron-specific enolase (NSE) has been demonstrated in miscellaneous tumors, including malignant lymphomas. Up to now thee results have been interpreted as non-specific, although NSE can be expressed by normal B and T lymphoid cells at a particular stage of differentiation. The aim of the present study was to investigate the expression of NSE in a large series of malignant lymphomas, including Hodgkin's disease, in relation to morphology and immunophenotype. Materials and Methods. Frozen and paraffin embedded sections from 16 cases of Hodgkin's disease (4 lymphocyte predominance, nodular; 4 mixed cellularity; 6 nodular sclerosis; 2 lymphocyte depletion) and 35 cases of non-Hodgkin's lymphomas were investigated in order to evaluate the expression of NSE, its specificity and correlation to immunophenotype or other immunological cell markers. Among the non-Hodgkin's lymphomas, there were 9 Anaplastic Large Cell (CD30+) Lymphomas; 2 Peripheral Large T-Cell Lymphomas; 22 Diffuse Large B-Cell Lymphomas and 2 Primary Mediastinal Large B-Cell Lymphomas. Results. In Hodgkin's disease, NSE showed a diffuse cytoplasmic reaction in Cd30+ Reed-Sternberg cells, whereas the "popcorn" (L&H) cells of lymphocyte predominance, nodular variant cases, were always negative. Among the non-Hodgkin's lymphomas, NSE positivity was found only in lymphomas expressing CD30. All the other cases were negative. No relationship was found between NSE and B- or T-immunophenotype Conclusions. Our results suggest that a link between NSE and CD30 expression exists in malignant lymphomas. However, at the moment this has not been sufficiently investigated and is subject to speculation.BACKGROUND:
The presence of gamma-enolase, gamma gamma dimer, or neuron-specific enolase (NSE) has been demonstrated in miscellaneous tumors, including malignant lymphomas. Up to now these results have been interpreted as non-specific, although NSE can be expressed by normal B and T lymphoid cells at a particular stage of differentiation. The aim of the present study was to investigate the expression of NSE in a large series of malignant lymphomas, including Hodgkin's disease, in relation to morphology and immunophenotype.
MATERIALS AND METHODS:
Frozen and paraffin embedded sections from 16 cases of Hodgkin's disease (4 lymphocyte predominance, nodular; 4 mixed cellularity; 6 nodular sclerosis; 2 lymphocyte depletion) and 35 cases of non-Hodgkin's lymphomas were investigated in order to evaluate the expression of NSE, its specificity and correlation to immunophenotype or other immunological cell markers. Among the non-Hodgkin's lymphomas, there were 9 Anaplastic Large Cell (CD30+) Lymphomas; 2 Peripheral Large T-Cell Lymphomas; 22 Diffuse Large B-Cell Lymphomas and 2 Primary Mediastinal Large B-Cell Lymphomas.
RESULTS:
In Hodgkin's disease, NSE showed a diffuse cytoplasmic reaction in CD30+ Reed-Sternberg cells, whereas the "popcorn" (L&H) cells of lymphocyte predominance, nodular variant cases, were always negative. Among the non-Hodgkin's lymphomas, NSE positivity was found only in lymphomas expressing CD30. All the other cases were negative. No relationship was found between NSE and B- or T-immunophenotype.
CONCLUSIONS:
Our results suggest that a link between NSE and CD30 expression exists in malignant lymphomas. However, at the moment this has not been sufficiently investigated and is subject to speculation
Vimentin-typing in diagnostic surgical pathology: a comparative study using four antibodies after different fixations
No full textVimentin-typing was carried out on various normal and neoplastic tissues using four anti-vimentin antibodies in order to evaluate the effect of different fixation treatments on tissue reactivity in comparison to the results obtained on frozen sections. All antisera were reactive on frozen material; on paraffin embedded material staining of tissues depended on the type of fixation method applied (formalin, methacarn or absolute alcohol) and each antibody behaved differently in relation to the fixative used. Only mesenchymal normal structures were revealed on frozen material whilst on paraffin embedded material three of the four antibodies reacted also with non-mesenchymal normal structures (epithelia, central and peripheral nervous system cells). All four antibodies decorated, regardless of treatment, neoplastic cells of mesenchymal and non-mesenchymal derivation, but not germ cells or germ cell tumors. The reactivity of vimentin to its specific antibodies depends on the fixative used: therefore, in routine pathology more than one antiserum should be available for testing. Furthermore, given the variety of non-mesenchymal structures stained by the anti-vimentin antibodies, the differential diagnosis of undifferentiated tumors must not be based on vimentin positivity alone. The expression of vimentin by non-mesenchymal neoplastic cells seems to parallel that of normal tissues during embryogenesis; therefore, this intermediate filament appears to be not only a marker of mesenchymal cells but also of many immature elements
Peripheral nerve sheath myxoma. Clinicopathological and immunohistochemical study of a morphologically distinctive myxoid peripheral nerve sheath tumor in the forelimb of a cat
No full textPeripheral nerve sheath tumors (PNST) are a class of nervous system tumors which arise in both schwann
cells and perineural fibroblasts. Benign and malignant PNSTs are reported to occur in all domestic animals.
In cats they represent 3% of all cutaneous and subcutaneous neoplasms. Only in dogs mixoid PNST has
been observed generally localized in the fingers. In humans, PNSTs are rare neoplasms, and nerve sheath
myxomas are a distinct neoplasia most commonly found in limb extremities
Osservazioni istochimiche e immunoistochimiche sull'ipofisi anteriore di un cane affetto da malattia di Cushing
Full text linkGli adenomi del lobo anteriore dell'ipofisi sono
neoplasie benigne piuttosto frequenti. Essi
mostrano aspetto circoscritto e accrescimento non
invasivo nei confronti dei tessuti circostanti. Il
tumore a cellule secernenti ACTH, che colpisce le
cellule cromofobe della pars anteriore dell'ipofisi,
è uno di questi e viene associato alla sindrome di
Cushing, causando evidente ipercortisolemia per
stimolazione della corteccia surrenale. Un cane
meticcio, femmina, di 7 anni, in terapia per
sospetta Sindrome di Cushing e pervenuto a
morte, è stato sottoposto ad accurato esame
necroscopico, durante il quale si procedeva tra
l'altro a prelevare ghiandole surrenali, polmone,
fegato, cute, muscoli e intera ghiandola pituitaria.
Su detti organi veniva eseguito l'esame
istopatologico per la ricerca delle lesioni tipiche
determinate dalla sindrome. Sulla ghiandola
pituitaria, aumentata notevolmente di volume,
venivano eseguite indagini istopatologiche
specifiche, mediante colorazione OFG, per
differenziare gli istotipi costituenti la pars
anteriore. Tale colorazione ha consentito di
riscontrare e identificare tra le cellule pituitarie gli
elementi acidofili, basofili e cromofobi; queste
ultime cellule, aumentate di numero, erano
d'aspetto omogeneo e formavano un nucleo
compatto e con scarso stroma al centro della
ghiandola. La caratterizzazione cromatica e la
differenziazione dai restanti istotipi ha reso
possibile identificare la neoplasia come adenoma
ipofisario di tipo "diffuso", caratterizzato per
l'appunto da cellule disposte a strati, con scarso
stroma e debole vascolarizzazione. Per verificare
l'ormonoattività delle cellule neoplastiche si è
proceduto all'esame immunoistochimico per la
ricerca dell'ACTH. Il risultato di tale indagine ha
dato esito positivo, confermando l'intensa attività secernente delle cellule oggetto di studio
Heterogeneity of T-cell rich large B cell lymphomas. Morfologic and immunophenotypic study
No full textUn raro caso di sarcoma granulocitico in un cane: osservazioni istopatologiche, istochimiche ed immunoistochimiche
No full textAnalysis of EGFR status in endometrial stromal sarcoma
No full textBackground: Endometrial stromal sarcomas (ESS) are rare neoplasms, which are currently classified in low grade ESS, with indolent growth, tendency to local recurrences and, more rarely, to metastasize, and undifferentiated endometrial sarcomas (UES), with a very aggressive behavior. Recently, Epidermal Growth Factor Receptor (EGFR) expression has been described in a large series of ESS, and a potential role of EGFR-targeted adjuvant therapies has been proposed. Aim of our study was to analyze EGFR immunohistochemical expression and EGFR gene amplification by FISH in a series of ESS.
Design: EGFR status was investigated in 10 ESS, including 7 low-grade ESS and 3 undifferentiated ESS. EGFR expression levels were assessed by immunohistochemistry with Dako EGFRpharmDX kit (DAKO, Glostrup, Denmark). Staining intensity and percentage of positive cells were scored for each case. Gene amplification analysis was performed with Dual-Color Fluorescence In Situ Hybridization (FISH) (Vysis, Downers Grove, IL, USA), with specific probes for EGFR gene (LSI Spectrum Orange) and Chromosome 7 centromeric region (CEP 7 Spectrum Green). At least 50 neoplastic nuclei for each case were scored for both grewen and orange signals, and the ratio EGFR/CEP7 was evaluated. Only cases with ratios of 2 or higher were considered amplified.
Results: Nine out of 10 (90%) ESS showed positive immunostaining. Six out of seven low-grade variants were positive, showing both cytoplasmic and membranous (5 cases) or only membranous staining (1 case). The staining intensity was interpreted as 3+ (3 cases), or 2+ (3 cases), with percentages of positive cells ranging from 60 to 80%. All three cases of UES were positive for EGFR, with membranous and cytoplasmic (2 cases) or only membranous (1 case) staining. The staining intensity was evaluated as 1+, 2+ and 3+, with percentages of positive tumor cells ranging from 50 % to 80%. FISH analysis showed EGFR/CEP7 ratios constantly below the cut-off value, ranging from 0.9 to 1.3.
Conclusions: Our study confirms that EGFR is frequently overexpressed in ESS. FISH analysis did not show EGFR amplification in any of the tumors, thus EGFR over-expression in ESS should be related to different genetic mechanisms. Further studies are needed to identify specific EGFR genetic abnormalities, potentially useful to select patients who might benefit from current EGFR-targeted therapeutic options
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