Asunto(s)

RESUMEN

PURPOSE: To study bone marrow micrometastases from colorectal cancer patients for the presence of K-ras mutations and to compare their genotype with that of the corresponding primary tumor. PATIENTS AND METHODS: Bilateral iliac crest aspiration was performed in 51 patients undergoing surgery for colorectal cancer, and bone marrow micrometastases were detected by immunohistochemistry. The presence of K-ras mutations was determined by single-strand conformation polymorphism analysis on both primary tumors and paired bone marrow samples and was confirmed by sequencing. RESULTS: In six patients with primary tumor mutations, it was possible to amplify a mutated K-ras gene also from the bone marrow sample. In three of those patients the pattern of K-ras mutations differed between both samples, in two patients the mutation was identical between the bone marrow and its primary tumor, and in one patient the same mutation plus a different one were found. Fifteen of 17 K-ras mutations found in primary tumors were located in codon 12, whereas in bone marrow, five of seven mutations were found in codon 13 (P =.003). CONCLUSION: Our results demonstrate that, at least for K-ras mutations, disseminated epithelial cells are not always clonal with the primary tumor and they question the malignant genotype of bone marrow micrometastases. They also indicate that different tumoral clones may be circulating simultaneously or sequentially in the same patient. Analysis of the type of mutations suggests that cell dissemination might be an early event in colorectal carcinogenesis.

Asunto(s)

RESUMEN

Bone marrow biopsy plays an important role in the clinical diagnosis of malignant lymphoma. Further diagnostic methods need to be established to increase accuracy in the light of advances over recent years in the immunophenotypical characterization of discrete lymphatic bone marrow lesions and the continuing difficulty in classifying them. This study compared the diagnostic value of flow cytometry to that of conventional bone marrow biopsy in 156 patients with 191 marrow biopsy specimens or bone marrow aspirates. The most important findings were that up to one-third of lymphomas could not be diagnosed by flow cytometry, and that the degree of infiltration was estimated as less than two-thirds. However, flow cytometric results were more satisfactory in acute lymphoblastic leukemia, lymphoblastic lymphoma, hairy cell leukemia, and chronic lymphocytic leukemia. In summary, flow cytometry has a complementary role in the staging of lymphoma but cannot fully replace conventional trephine biopsy.

Asunto(s)

RESUMEN

Here we report that acetone fixation at -18 degrees C with subsequent embedding in methyl-/butylmethacrylate is a reliable method for the routine processing of bone marrow biopsies. This method allows good conventional histological visualization of morphological details, which is comparable with other fixation procedures. The essential advantage of this method is that a wide range of monoclonal antibodies and polyclonal antisera can be used for immunohistochemical investigations for diagnostic and scientific purposes. The addition of 5% polyethylene glycol 400 to the acetone minimizes freeze-related artefacts. The immunohistochemical demonstration of a number of antigens is mostly affected by the medium used for slide preparation and to a lesser extent by the concentration of benzoylperoxide used for polymerization. Performing polymerization at 4 degrees C and using N, N-dimethyl-p-toluidine as accelerator allows the concentration of benzoylperoxide to be reduced to 0.2 g% (8.3 mmol). Under these conditions the methacrylate embedding procedure has only minimal effects on the quality of immuno- and enzyme histochemistry. Additionally, the simplified method for removing the polymerization inhibitor from the methacrylate components and the shortened impregnation step are further advantages of the embedding method described here.

Asunto(s)

RESUMEN

We report two cases of the so-called adenomatoid tumor of the uterus, which have been detected in patients who underwent surgery for leiomyomas. The clinical signs, origin and immunohistochemical characteristics of the adenomatoid tumor are described. Adenomatoid tumors are slow growing epithelioid neoplasias with a co-expression of vimentin and cytokeratins. The characteristic cytokeratins are numbered 7, 8, 18, 19 and 5. The mesothelial histogenesis of the tumor can be confirmed. Our results rule out origins from Müllerian or mesonephrogenous ducts and angioma or adenoma. Considering our experiences, adenomatoid and leiomyoma cannot be distinguished macroscopically. The hysterectomy or salpingo-oophorectomy, primarily performed under other diagnoses, are the therapies of choice.

Asunto(s)

RESUMEN

We report on a 36-year old male patient with clinically prolonged intermittent claudication of the right leg. An operative specimen measuring 8.0 cm of the A. poplitea was sent for examination, which was sheathed by an aneurysmal cyst having a maximal diameter of 1.5 cm. Examination under the light microscope showed an incomplete septated ganglion-like cystic formation with flat connective tissue-like cells or even larger histiocytoid cell elements as inner lining. Immunohistochemically, the cells on the inner lining of the cyst showed to be strongly positive to macrophage marker PG-M1, KP1 and Ki-Mp1. The endothelium of the vessels of the wall of the cyst showed a marked expression of cytokeratin 18. Immunohistochemically as well as in conventional histology, there are general parallels between cysts in cystic adventitial degeneration, ganglia and normal synovia as the two last mentioned tissues also show an expression of cytokeratin 18 at the endothelia of smaller vessels as well as an expression of macrophage-associated antigens on cells of the inner lining. Aetiopathologically, the cysts developing in the course of the disease are rather adventitial ganglia.

Asunto(s)

RESUMEN

Immunohistochemical and histochemical methods are increasingly used and their application in surgical pathology is obvious. Especially we used these methods on bone marrow core biopsies. Optimal and comparable results have been obtained by using different methods after halving the biopsy cores longitudinally and/or transversally. The two halves were used for cytologic imprints. Two parts of the biopsy cores were embedded in polymethacrylate at low temperature (-20 degrees C). The methacrylate-embedded biopsy part for routine histology was fixed in Schaffer's solution (methanol-formalin-fixative). The methacrylate-embedded undecalcified section of 4 microns may be stained by most stains commonly employed in routine histopathology after removal of the plastic. The sections are virtually free of artefacts such as shrinkage and swelling in the light microscope. The second methacrylate-embedded part of biopsy cores was fixed in 2% paraformaldehyde with 5% sucrose in 0.02 M phosphate buffer (pH 7.4) and dehydrated in ethyleneglycolmonobutylether. All procedures were carried out at 4 degrees C. This method permits the use of immunohistochemical and histochemical procedures. The immunohistochemistry was carried out at sections of 4 microns after removal of the plastic with methoxide and use of proteolytic enzyme (0.1% alpha-chymotrypsin) to unmask antigens in sections. Surface and intracellular immunoglobulins were very well detected with the indirect FITC method. The histochemical procedures are carried out at sections of 7-8 microns after removal of plastic with xylene and toluol. The sections were incubated for specific esterase and nonspecific esterases, acid and alkaline phosphatase and then examined by light microscopy. A third part of biopsy cores may be immediately frozen, and cryostat sections are stained and evaluated for rapid diagnosis and used for immunohistologic analysis with mono- and polyclonal antibodies (FITC method) and/or histochemical investigations. Imprints of biopsy cores are evaluated for cytological, cytochemical and/or immunocytological analysis with mono- and polyclonal antibodies (FITC method). The cryostat sections and the imprints are fixed for all methods with 2% paraformaldehyde and 5% sucrose in PBS (0.02 M, pH 7.4) at 4 degrees C for 30 minutes. The best diagnostic results were obtained in the myelo- and lymphoproliferative disorders using the combination of methods described here. Examples were demonstrated.

Asunto(s)

RESUMEN

The influence of formaldehyde fixation, dehydration and polymethacrylate embedding on the results of immunofluorescence staining of immunoglobulin and enzymehistochemical demonstration of hydrolases, especially acid phosphatase and alpha-naphthylacetate esterase in human tonsils and bone marrow were studied. The best results were achieved by using 2% formaldehyde and 5% sucrose in 0.02 M phosphate buffer (ph 7.4) for fixation and ethyleneglycol monobutylether for dehydration. The procedures were carried out at 4 degrees C. For tissue embedding we used the commercially available polymethacrylate Kalloplast R. The polymerisation was carried out at -20 degrees C for 18 hours. This method permits a good preservation of morphological details and the survival of antigenic determinants and enzyme activity. Trypsin, pepsin and alpha-chymotrypsin were used to "unmask" the antigenic determinants in methacrylate sections. Trypsin and alpha-chymotrypsin revealed comparable results, but because of better practicability we used alpha-chymotrypsin. Using the described fixation, dehydration and embedding procedures it was possible to demonstrate both intracellular immunoglobulins (gamma, alpha and mu heavy chains; kappa and lambda light chains) and surface-bound immunoglobulins (mu and delta heavy chains; kappa and lambda light chains). Comparable results were achieved in human bone marrow biopsies. The results of histochemical demonstration of both enzymes were better in bone marrow sections than in that of the tonsils. We think, that the presented method is suitable in the diagnosis of myelo- and lymphoproliferative disorders on both the bone marrow and lymphatic tissue.

Asunto(s)

RESUMEN

Minor glomerular abnormalities (MGA) with hypercellularity (according to the WHO-nomenclature) are one of the most frequent glomerular lesions. Minimal proliferative changes in the glomerular structure can be proven only with the aid of morphometric methods. Morphometric glomerular studies were carried out in MGA with hypercellularity and with rare or minor deposits of immunoglobulins and/or complement (C3) or without deposits. Clinical symptomatology was variable (minimal to mild proteinuria, massive proteinuria, haematuria or haematuria with proteinuria). The groups examined were divided as follows: MGA without deposits and with minimal (mild) proteinuria. MGA with minor deposits and with minimal (mild) proteinuria. These two groups were statistically compared with: normal glomerular structure (after Wehner 1974); MGA with massive proteinuria or nephrotic syndrome (includes the minimal changes with nephrotic syndrome), which showed minor deposits of complement; diffuse mesangial proliferative glomerulonephritis (IgA-nephritis). The glomerular cell density, i.e. the total number of glomerular cells, averaged 3.48 cells/1,000 micron 2 in the first group and 4.26 cells/1,000 micron 2 in the second group. In normal renal corpuscles the average was 2.30 cells/1,000 micron 2. The first group has an average of 51% and the second group has an average of 84% higher cell density than normal renal corpuscles. The cell density in diffuse mesangial proliferative glomerulonephritis (IgA-nephritis) is increased by 160% compared with the norm. The first group was not statistically different in cell density from MGA with high proteinuria. We conclude, that MGA with hypercellularity and minimal to mild proteinuria represents a minimal mesangial proliferative glomerulonephritis.

Asunto(s)

RESUMEN

The investigation is based on 49 autopsies at which chronic glomerulonephritis (GN) was found. The glomerular findings were classified by the WHO classification of renal diseases. The ratio of kidney weight (g) to body height (cm) gave a constitutional kidney index which correlated with the degree of global and segmental (more than 50%) sclerosis of glomeruli in chronic GN (diffuse intracapillary type). The negative correlative coefficient from simple linear regression was rho = -0.606. Chronic GN was then further subdivided into four groups which mutually correlate: diffuse sclerosing GN (so-called end-stage kidney). Index: 0.27 g/cm; diffuse sclerosing GN (over 80% glomerular sclerosis). Index: 0.49 g/cm; diffuse proliferative and extensive sclerosing GN (more than 50% and less than 80% sclerosis) Index: 0.59 g/cm; diffuse proliferative and mild to moderate sclerosing GN (less than 50% sclerosing). Index: 0.93 g/cm. The indices of the diffuse extracapillary GN were high in comparison with diffuse intracapillary GN. The kidney index of diffuse extracapillary proliferative and extensive sclerosing GN with over 80% fibrous crescents was 0.78 g/cm. Index of diffuse extracapillary proliferative and mild to moderate sclerosing GN, mostly epithelial and fibro-epithelial, few fibrous crescents was 1.30 g/cm. The mean values of the indices for normal kidneys were (males) 0.78-0.81 g/cm and (females) 0.73-0.75 g/cm (age: 20-60 years). These results may be used for correlative investigations with morphometric parameters of renal osteopathy.

Asunto(s)

Asunto(s)