J. Aneiros

Fibrolamellár hepatocellular carcinoma. An immunohistochemical and ultrastructural study

Two cases of fibrolamellar carcinoma of the liver are reported in young female patients of 12 and 21 years of age. Small amounts of perinuclear alpha‐fetoprotein were found, unrelated to hyaline globules, as well as alpha1‐antitrypsin in a periglobular fashion in isolated cells. Ferritin was present in a large number of cells. Ultrastructurally, the well differentiated nature of the neoplasm was substantiated by previously unreported findings such as intercellular lumina analogous to bile canaliculi and peroxisome‐like bodies containing a central crystalloid. Filamentous material resembling Mallorys type of hyaline was also found. We conclude that both immunohistochemical and ultrastructural features reflect a high degree of differentiation.

Influence of intrarenal deposits of ciclosporin A on acute renal transplant rejection.

Immunohistochemical techniques were used to study the presence of ciclosporin A (CsA) and leukocyte subsets in 36 posttransplant renal biopsy specimens histologically diagnosed as acute graft rejection. Glomeruli from patients with CsA deposits contained more leukocytes (p < 0.05) than glomeruli from tissues without deposits. In contrast, the interstitium from patients without deposits contained significantly more B lymphocytes than interstitia from kidneys with CsA deposits. In both glomeruli and interstitia, the CD4/CD8 ratios were higher in tissues without deposits, although the difference was not significant. The plasma levels of creatinine increased with the intensity of renal CsA deposits, and significantly more patients on hemodialysis had deposits as compared with patients not on hemodialysis. Our findings suggest two types of acute nonvascular rejection: (1) predominantly interstitial, with a good prognosis, characterized by low numbers of intrarenal CsA deposits and a predominance of B lymphocytes and (2) predominantly glomerular, with a poor prognosis, characterized by high levels of intrarenal CsA and a predominance of CD8-positive cells and macrophages.

Mononuclear Cell Subsets in IgM Mesangial Proliferative Glomerulonephritis

Glomerular and interstitial leukocyte subpopulations were analyzed in renal biopsies from 18 patients with IgM mesangial proliferative glomerulonephritis (IgM MPGN), 19 patients with minimal change nephrotic syndrome (MC) and 10 patients with immune-negative mesangial proliferative glomerulonephritis (IN MPGN), by immunoperoxidase techniques with monoclonal antibodies. Mesangial cell proliferation was strongly correlated with absolute numbers of intraglomerular T lymphocytes (r = 0.71; p < 0.01) in IgM MPGN, but not in MC or IN MPGN. Significant differences were found in the numbers of macrophages, CD4- and CD8-positive glomerular cells (Students t test p < 0.01, 0.05 and 0.01, respectively) in IgM MPGN, but not in MC or IN MPGN. The numbers of CD45-, CD3- and CD8-positive cells also differed in each patient group (ANOVA p < 0.01, 0.05 and 0.05, respectively), the greatest and smallest values appearing in IgM MPGN and MC, respectively. Multiple regression test showed initial proteinuria values in IgM MPGN to be closely dependent on the density of neutrophils, macrophages, T and B lymphocytes and CD4 cell inflammatory infiltrates (r2 = 0.92; p < 0.01). At the end of the follow-up, proteinuria in IgM MPGN, but not in MC or IN MPGN, was dependent on T cell infiltrate (r2 = 0.97; p < 0.01). Our findings suggest that proteinuria in IgM MPGN results from local mesangial damage rather than from the effects of a soluble circulating factor, as has been proposed for MC. The clinical and immunohistochemical differences observed between these two processes support the notion that they should be considered as separate entities.

Hamartomatous solitary polyp with malignant progression in the jejunum. A histochemical and immunohistochemical study by light and electron microscopy.

A case of solitary hamartomatous jejunal polyp with adenomatous and carcinomatous changes in a 16‐year‐old girl is reported. In the hamartomatous polyp, neutral and acid non‐sulfate mucosubstance was detected, principally in goblet cells; carcinoembryonic antigen was demonstrated on the surfaces of the microvilli and luminal border of the crypts and glands; absorptive columnar, goblet, argentaffin, argyrophil and Paneth cells were evident. The adenomatous and, mainly, the carcinomatous areas revealed a decreased amount of mucosubstance and a variable degree of positive intracytoplasmic staining for carcinoembryonic antigen. With electron microscopy, the adenomatous areas showed columnar absorptive cells and mucus‐secreting goblet cells; also immature columnar cells were observed in the dysplastic zones. To our knowledge, this is the first study to document the histochemical, immunohistochemical and ultrastructural features of a hamartomatous polyp with neoplastic transformation. ACTA PATHOL JPN 38: 1031∼1040, 1988.

Presence of Cytomegalovirus Genome and Leucocyte Subsets in Renal Transplant Biopsies: Relationship with Prognosis

The influence of immunosuppressant therapy and of the presence of CMV genome on the distribution of lymphoid subpopulations of the inflammatory infiltrate in renal graft rejection was analyzed, as was the role of both factors in the evolution and survival of the graft. The study included 22 patients treated with Cyclosporin A (CsA) and 22 patients treated with Azathioprine (AZA). Inflammatory infiltrate was studied by immunostaining with a panel of monoclonal antibodies, and CMV DNA was detected by in situ hybridization on tissue sections. In patients treated with CsA, increased cellularity was found at both glomerular and interstitial levels, consisting mainly of macrophages and T-cells, which was consistent with the higher rate of glomerulointerstitial rejection found in this group. In contrast, the vascular type of rejection predominated in AZA treated patients. However, the presence of CMV DNA did not influence the phenotype of the inflammatory infiltrate, and was not associated with any specific lesion. Furthermore, the final outcome of the renal graft was independent of the detection of CMV. Therefore, this study provides no evidence of any active role of the CMV genome in renal graft rejection, and suggests that therapy should be adapted to the type of rejection as defined on morphologic and immunophenotypic grounds.

Human melanoma cell lines: an immunofluorescence and ultrastructural study

Two human melanoma cell lines (OAL‐1 and OAIy‐2) were obtained from primary tumors. Electron microscopy and indirect immunofluorescence for S‐100 protein and human melanoma associated antigen p97a were used to characterize the cell lines. Ultrastructural correlation between primary tumor cells and cultured cells was investigated. The ultrastructural features of OAL‐2 cells were similar to those of primary tumor cells. However, OAL‐1 cells showed a fibroblast‐like appearance, quite different from that of the primary tumor cells. This fibroblast‐like appearance persisted after 50 subcultures of the OAL‐2 cell line and suggests cellular dedifferentiation. No spontaneous re‐differentiation of the cells to the original phenotype of the primary tumor cells was observed even after 50 subcultures.

Infantile myofibromatosis: histogenesis

Sir: Marshall & Warren’s report (1984) on active chronic gastritis has renewed the interest in micro-organisms in the stomach, now called Campylobacter pyloridis. Culturing of gastric biopsies is the most specific method for the identification of campylobacter in gastric mucosa. Since the micro-organism requires a very specific medium and only grows under microaerophilic conditions this method is of limited sensitivity (30-60%) (Marshall & Warren 1984, Jones, Lessels & Eldridge 1984). Therefore, most investigators rely on histological staining of Campyfobacfer pyloridis for the diagnosis of campylobacter-associated gastritis. For this purpose the silver staining technique of Warthin & Starry (1920) is commonly applied. This method however has certain drawbacks. It requires technical skill and is time consuming as well as expensive. Moreover. silver precipitation in the mucus covering the gastric mucosa may interfere with the interpretation of the findings. False positive and false negative results are thus possible. Rathbone, Wyatt & Heatly (1926) mentioned a modified Giemsa as an alternative staining method for the demonstration of campylobacter-like micro-organisms. The modification consists of omission of the differentiation step with acetic acid (Gray, Wyatt & Rathbone 1986). We have compared the Warthin Starry staining technique with this modified Giemsa stain. Gastric biopsies from 34 patients with cultureproven campylobacter-associated gastritis, were stained and examined blindly. With the Warthin Starry technique 27 cases of campylobacterassociated gastritis were positively identified, whereas 32 cases were detected using the modified Giemsa stain. The modified Giemsa stain, therefore, appears to be superior in predicting a positive culture compared with the Warthin Starry staining method. In our experience this is mainly due to silver precipitation preventing the detection of small numbers of Campylobacter pyloridis. We conclude that the modified Giemsa stain, apart from being cheaper and easier to perform, is more sensitive and therefore appears to be preferable for the histological demonstration of Campylobacter pyloridis in gastric biopsies. H.V .P.J.Potters R.J.L.F.Loffeld EStobberingh J.P.van Spreeuwel J. W. Arends* Departments of *Pathology, Interns[ Medicine arid Microbiology, University of Limburg, Mnastricht, The Netherlands

Cystosarcoma phyllodes: epithelial and mesenchymal changes

Sir; It is generally accepted that epithelial and mesenchymal changes in cystosarcoma phyllodes (phyllodes tumour) are infrequent (McDivitt, Urban & Farrow 1967, Azzopardi 1979). In a recent paper published in Histopathology, Salisbury & Singh (1986) described two cases with apocrine metaplasia, yet the real incidence of these changes and their aetiology are not known. We have recently seen one case. The patient was a 48-year-old woman who presented with a left breast mass measuring 15 cm in maximum diameter. Histologically, it had a typical phyllodes architecture with epithelial clefts and stromal hypercellularity of variable intensity. The lesion was benign. There were also areas with apocrine metaplasia, lobular proliferation and typical and atypical intraductal epithelial hyperplasia (Figure 1). The stroma contained focal areas of smooth muscle. It is considered that the lobular changes are primary and that the ductal changes are secondary (Azzopardi 1979). We suggest that these changes might all be primary. This raises the possibility that at least some phyllodes tumours may be ductal or mixed (ductal and lobular) rather than being solely of Lobular origin. Lobular carcinoma is the tumour type most frequently associated with phyllodes tumour. However, ductal carcinoma may also be found (Norris & Taylor 1967). We consider that a ductal carcinoma could originate from previous atypical intraductal hyperplasia. Smooth muscle may very rarely be observed in phyllodes tumours (Norris & Taylor 1967). We have studied two fibroadenomas with this mesenchymal change. In the present case smooth muscle was also observed. This reflects

Immunohistochemical Markers of Renal Tubular Injury and Cyclosporin Nephrotoxicity in Kidney Allograft Biopsies

Dr. Raimundo García Del Moral, Departamento de Anatomía Patológica, Facultad de, Medicina, Universidad de Granada, Avda. de Madrid, s/n, E-18012 Granada (Spain) Dear Sir, The differential diagnosis between renal allograft rejection and chronic cyclosporin (CS) nephrotoxicity presents serious difficulties for the histopathologist [1]. Vimentin expression in the cytoplasm of proximal tubule cells from drug-induced toxic nephropathies suggests that this intermediate filament could be used as a marker of both active cell regeneration and irreversible chronic tubular injury [2]. Chronic tubular injury has also been associated to changes in the expression of other antigens such as the epithelial membrane antigen (EMA), which is normally expressed by the distal tubule and collecting duct [3], and the CD15 antigen (Leu Ml) on the proximal tubule brush border [4]. We have studied the expression of vimentin, EMA and CD15 in 48 renal allograft biopsies from patients subject to 2 different immunosuppressive protocols: prednisone plus low-dose CS (n = 31), and prednisone plus azathioprine (AZA; n = 17). Controls (n = 10) were obtained from otherwise normal kidneys removed after traumatic rupture. In the group treated with CS, a histopathological diagnosis of glomerulointerstitial allograft rejection was reached in 18 cases, while 5 of them showed chronic vasculointerstitial rejection, 4 acute interstitial rejection, 2 acute vascular rejection, 1 chronic transplant glom-erulopathy and 1 recidivant focal and seg-mental hyalinosis. Among those patients treated with AZA, the most common histolog-ical diagnosis was chronic vasculointerstitial rejection (5 cases), followed by acute vascular rejection (4 cases), acute interstitial rejection (4 cases) and acute glomerulointerstitial rejection (4 cases). All biopsies were evaluated in a semiquantitative manner (0 = absent; l = mild; 2 = severe) for the presence of CSassociated changes including striped interstitial fibrosis, tubular calcifications, megamitochondria and hyaline droplets in the proximal tubules, peritubular capillary congestion, vascular myointimal fibrosis and hyaline arteri-opathy. Ultrastructural confirmation of megamitochondria and hyaline droplets was performed in 50% of cases. The expression of vimentin, EMA and CD15 by the tubular cells was analyzed by avidin-biotin immunoperoxidase in paraffin-embedded tissue sections. The number of immunostained tubular profiles per 10 high-power (400 ×) microscopic fields was assessed.

Meningioma secretor. Correlación clínicopatológica y revisión de la literatura

Resumen El termino meningioma secretor corresponde a un subtipo de meningioma cuyas caracteristicas histopatologicas estan representadas por un patron sincitial, presencia difusa de inclusiones hialinas e hiperplasia pericitaria focal. Los hallazgos ultraestructurales e inmunohistoquimicos revelan la maxima expresion de la conocida bipotencialidad, mesenquimal y epitelial, del meningioma. Estas peculiaridades morfologicas se acompanan de una mayor rapidez de presentacion clinica y un intenso edema peritumoral, que lo hace dificilmente reconocible como meningioma. El hallazgo de antigeno carcinoembrionario (CEA) a nivel del tejido tumoral apunta la posibilidad de utilizar este marcador a nivel serico y de LCR en el seguimiento de estos enfermos, asi como incluir al meningioma secretor en el diagnostico diferencial de pacientes con niveles de CEA elevados.