Chemotherapy of invasive thymoma.

Thirty-two patients with stage III or IV invasive thymoma (14 women and 18 men; median age, 40 years) were treated at the Padua Medical Oncology Department from 1977 to 1988. All patients received the following chemotherapy in 4-day courses: 50 mg/m2 of cisplatin intravenously (IV) and 40 mg/m2 of doxorubicin IV on day 1; 0.6 mg/m2 of vincristine IV on day 3; and 700 mg/m2 of cyclophosphamide IV on day 4 (ADOC). The courses were repeated every 3 weeks, and toxic effects were tolerable. The radiologically defined overall clinical response rate (complete plus partial response) was 91% with 47% clinical complete remissions; median time to progression was 11 months (range, 0 to 96) and the median estimated (Kaplan-Meier) progression-free interval was 22 months. Five of the 15 clinical complete remissions were pathologically confirmed at thoracotomy. We believe the ADOC regimen qualifies for adjuvant and preoperative treatment of invasive thymoma due to the high complete response and overall response rates.

Incident cases of primary liver cancer (PLC): proposal for the use of a standardised method in case-definition.

We defined some standardised criteria for classifying incident cases of liver cancer into either Primary Liver Cancer (PLC) or Unspecified Liver Cancer (ULC), on the basis of the diagnostic procedures performed. A pilot hospital-based study (98 cases) was carried out in Verona, northern Italy, in order to assess the feasibility of the method. The same protocol was subsequently applied in a population-based study (349 cases) in Bresica, northern Italy. The percentage of cases with histological verification was 38.7 and 41.8%, respectively, with a wide variation among different hospitals. The percentage of cases we attributed to the PLC category was 78.6% in the hospital-based study and 78.8% in the population-based study. No differences in the proportion of cases attributed to PLC were found according to patients' age, sex or hospital of admission. Repeatability of the method was assessed through a cross-panel review of 198 cases, with a 91.9% interobserver agreement. Implications of this method are discussed and some suggestions for cancer registration and future research are proposed.

Immunohistochemical analysis of thymoma. Evidence for medullary origin of epithelial cells.

The histologic organization of lymphoid and nonlymphoid (epithelial and interdigitating) cells in a thymoma has been compared to that of the normal thymus. Enzyme and immunohistochemical methods were applied, using both conventional antisera (to cytokeratin) and monoclonal antibodies (to epithelial cells, HLA-DR and lymphoid subsets). Throughout the tumor, the epithelial cells shared phenotypical similarities with the epithelial cells of thymic medulla (RFD-4 positive, cytokeratin strongly positive, and HLA-DR essentially negative). On the other hand, the lymphoid cells were heterogeneous in phenotype and distribution, and "mimicked" the distribution seen in the normal infant thymus. Immature thymocytes of cortical type (TdT+, OKT6+, OKT3-) were predominant in the areas with moderate lymphocytic infiltration (ML). Mature T-lymphocytes (TdT-, OKT6-, OKT3+) were found mainly in areas with scanty lymphocytes (SL) together with an additional population of HLA-DR positive interdigitating and HLA-DR+, OKT6+ Langerhans'-type cells. These findings indicate that in thymoma tissue, the lymphoid elements of cortical type are apparently surrounded by an inappropriate (medullary) epithelium.

Myasthenia gravis: immunohistological heterogeneity in microenvironmental organization of hyperplastic and neoplastic thymuses suggesting different mechanisms of tolerance breakdown.

Four samples of thymoma obtained from patients affected by myasthenia gravis have been immunohistologically analysed on cryostat sections using a panel of antisera and monoclonal antibodies specific for antigens which define different stages of intrathymic lymphocyte differentiation and antigens specific for different types of thymic epithelial cells (cortical, medullary). When the thymoma samples were compared to age-matched normal thymuses and hyperplastic thymuses obtained from patients with myasthenia gravis some evident microenvironmental differences could be demonstrated using these reagents. In all the thymoma samples in fact the neoplastic lobules appeared as grossly enlarged cortical-type areas, formed by accumulations of T lymphocytes exhibiting the cortical immature phenotype (TdT+, T6+, etc.) within a network of putatively neoplastic epithelial cells characterized by cortical phenotype as defined by reactivity with various monoclonal antibodies (RFD4-, MR3+). These 'cortical' epithelia showed some abnormal features such as lack or irregular distribution of HLA-DR and enhanced keratin expression. Small areas of 'medullary' differentiation could be observed in 3/4 thymoma samples. In thymic hyperplasia, on the other hand, the cortical areas appeared somewhat compressed (but comparable to those observed in normal age-matched samples) by enlarged medullary areas. The expansion of medullary areas was due to the infiltration of 'peripheral' lymphoid tissue intruding through the extraparenchymal zone and forming organized B and T areas. These observations are discussed in the light of the clinical heterogeneity observed in myasthenia gravis.

Dipeptidyl(amino)peptidase IV (DAP-IV) histochemistry on normal and pathologic lymphoid tissues.

The enzyme glycyl-proline-naphthylamidase (dipeptidyl-amino-peptidase IV), (DAP-IV) has been histochemically analysed in normal and pathological specimens of different lymphoid tissues. In all the tissues examined, the enzyme appeared to be highly specific for T cells. Using chloroformacetone fixation and sections of proper thickness, DAP-IV could be successfully demonstrated in cortical thymocytes, which exhibited weak reactivity, as well as in medullary thymocytes which showed a more intense and variable reactivity. A similar reactivity was observed in T cells of peripheral blood, lymph node, and spleen. Various acute lymphoblastic and nonlymphoblastic leukemias and malignant lymphomas were studied using the histochemical method for DAP-IV. Malignant cells from all the acute leukemias and from the B-cell lymphomas were DAP-IV unreactive, while strong reactivity was observed in one case of T-CLL and one case of T-PLL. The possible relationship of DAP-IV positivity pattern with T-cell maturation and its potential use as a diagnostic tool in lymphoproliferative disorders are discussed.

Enzyme histochemistry on normal and pathologic paraffin-embedded lymphoid tissues.

So far, enzyme histochemical examination has been applied, with few exceptions, either to tissue imprints or to cryostat sections of freshly collected samples. This procedure is not easily applicable in routine histopathologic examination. In this study, a simplified tissue embedding procedure is presented which can be performed using an automatic tissue changer. The paraffin embedded samples can be used for both conventional histopathologic examination and for demonstrating enzymes in sections. The enzymes studied (alkaline phosphatase, alpha-naphthyl acetate esterase, acid phosphatase, tartrate resistant acid phosphatase, ATPase, peroxidase, and chloroacetate esterase) gave comparable results in formalin-fixed cryostat sections and paraffin sections in both normal and pathologic lymphoid samples. The only exception was ATPase, which could not be demonstrated on paraffin-embedded material. The technic described has broad application in the analysis of lymphoid diseases.

Blastic OKT6-positive proliferation preceding malignant histiocytosis.

A 45-year old male presented latero-cervical lymphoadenopathy. Biopsy revealed a malignant proliferation of immature "lymphoid" cells bearing T6 antigen and HLA-DR but negative for other lymphoid markers, suggesting a phenotype similar to Langerhans cells. The patient did not receive any therapy and six months later developed a histologically typical malignant histiocytosis, involving spleen and liver. Other reported cases of lymphoid malignancies (two bearing the T6 antigen on blast cells) preceding malignant histiocytosis were found and compared with ours. Most of these cases were characterized by the pediatric age of the patients and were presented as acute leukemias exhibiting, in at least some of them, reliable T-cell markers. Our case appears to represent, on the other hand, a blastic proliferation of precursors of both histiocytes and Langerhans dendritic cells which eventually progressed to malignant histiocytosis. The relevance of this observation in the debate on the origin of Langerhans cells and the relationships existing between macrophages and dendritic cells is discussed.

Hyaline-vascular type of Castleman's disease (angiofollicular lymph node hyperplasia) with monotypic plasma cells. An immunohistochemical study with monoclonal antibodies.

A case of angiofollicular lymph node hyperplasia (Castleman's disease) characterized by monotypic (IgG+, lambda+) plasmacytosis is described. Fresh tissue was available and a thorough immunohistochemical analysis of lymphoid and non-lymphoid cells was performed on cryostat sections. Although lymphoid follicles were numerous and exhibited some abnormal features they did not appear part of the monoclonal cell proliferation. Follicular lymphocytes were mixtures of Kappa+ and lambda+ cells. Vessels penetrating within these abnormal follicles expressed reduced levels of FVIII and Leu-M5 antigens and exhibited thicker layer of collagen type IV. The analysis of T-cell subsets showed a normal (3:1) T4/T8 ratio. This case extends to the mixed variant of hyaline-vascular Castleman's disease, the neoplastic potential previously associated to the plasma cell variant of the disease.

Enzyme histochemical analysis on cryostat sections of human bone marrow.

A recently developed procedure, that has been shown to be suitable for detailed immunohistological analysis, has been used to prepare cryostat sections of bone marrow to investigate whether enzyme-histochemical techniques are also feasible on such material. A selected group of enzymes, some of which are inhibited or destroyed in paraffin- or plastic-embedded samples, have been demonstrated. The morphological details obtained were satisfactory in the preparations. The enzymes were dipeptidyl(amino)peptidase IV (for T lymphocytes); tartrate-resistant acid phosphatase (for hairy cell leukaemia); acid phosphatase and non-specific esterase (for macrophages and monocytes); ATPase and 5'nucleotidase (for B lymphocytes); and peroxidase or chloroacetate esterase (for granulocytic cells). In these preparations strong enzyme activities were shown. In adjacent sections the immunological analysis of membrane markers could also be performed contributing to a comprehensive study of the normal and malignant bone marrow cells.

A method for detection of human papillomavirus DNA in stored slides of stained cervical smears.

A simple method was developed for extraction of DNA from stored slides of Papanicolaou stained cervical smears. HPV type 16 DNA was detected by DNA hybridization in 7/10 samples from known HPV-16 positive patients, whereas the 10 samples from negative patients were also negative with our assay. Using our method for obtaining data from stained cervical smears, it will be possible to design and perform historical cohort studies on stored material.

[Mortality from malignant tumors in residents of the city of Verona in 1980]. / Mortalità per tumore maligno nei residenti della città di Verona al 1980.

Malignant tumours mortality among residents of the city of Verona (267,703 at 31-12-1980) during the year 1980 is assessed from the ISTAT individual death cards and/or municipal death certificates (especially in the case of deaths outside the municipality). The figures are broken down by site, apparatus or system (in accordance with the VIII-ICD), sex, age at death, and compared with the Italian mortality figures for 1976 (indirectly standardised) and those for the province of Verona for 1976-77 (directly standardised). Tumour mortality per site was generally higher than the Italian level. This is line with the differences noted between geographical areas and the similarity of the rates in more industrialised areas. A salient finding was that lung tumour mortality exceeded that for the province of Varese, which is among the highest in Italy entered on the Register of Tumours. Genital and breast tumours were responsible for the highest number of deaths in women, while stomach cancer was the second cause of death in both sexes. The study will be completed with an analysis of tumour deaths during 1980 and 1981 in the province of Verona as a whole.