Study of major genetic factors involved in pituitary tumorigenesis and their impact on clinical and biological characteristics of sporadic somatotropinomas and non-functioning pituitary adenomas

Genetic and functional aberrations of guanine nucleotide-binding protein, alpha stimulating (GNAS), aryl hydrocarbon receptor interacting protein (AIP), and pituitary tumor transforming gene (PTTG) are among the most prominent events in pituitary tumorigenesis. A cohort of Brazilian patients with somatotropinomas (n=41) and non-functioning pituitary adenomas (NFPA, n=21) from a single tertiary-referral center were evaluated for GNAS and AIP mutations and gene expression of AIP and PTTG. Results were compared to the clinical and biological (Ki67 and p53 expression) characteristics of tumors and their response to therapy, if applicable. Genetic analysis revealed that 27% of somatotropinomas and 4.8% of NFPA harbored GNAS mutations (P=0.05). However, no differences were observed in clinical characteristics, tumor extension, response to somatostatin analog therapy, hormonal/surgical remission rates, Ki67 index, and p53 expression between mutated and non-mutated somatotropinomas patients. PTTG overexpression (RQ mean=10.6, min=4.39, max=11.9) and AIP underexpression (RQ mean=0.56, min=0.46-max=0.92) were found in virtually all cases without a statistically significant relationship with clinical and biological tumor features. No patients exhibited somatic or germline pathogenic AIP mutations. In conclusion, mutations in GNAS and abnormal PTTG and AIP expression had no impact on tumor features and treatment outcomes in this cohort. Our data support some previous studies and point to the need for further investigations, probably involving epigenetic and transcriptome analysis, to improve our understanding of pituitary tumor behavior.

Paroxysmal atrial fibrillation and insidious neck pain

Paroxysmal atrial fibrillation (AF) is an arrhythmia usually secondary to autonomic imbalance, and it may occur in the absence of any structural heart disease. The case of a patient with paroxysmal AF, in whom the arrhythmia may have been a presenting symptom of a later diagnosed cervical schwannoma, is reported.

Hantavirus pulmonary syndrome in the State of São Paulo, Brazil, 1993-1998

Between 1993 and 1998, 10 cases of clinical hantavirus infection were diagnosed in Brazil. Hantavirus-specific IgM, or positive immunohistochemical analysis for hantavirus antigen, or positive reverse transcription-polymerase chain reaction results for hantavirus RNA were used to confirm nine of these cases; eight were hantavirus pulmonary syndrome (HPS), and one was mild hantavirus disease. The remaining clinical case of hantavirus infection was fatal, and no tissue was available to confirm the diagnosis. During the first 7 months of 1998, five fatal HPS cases caused by a Sin Nombre-like virus were reported from three different regions in the State of São Paulo, Brazil: two in March (Presidente Prudente Region), two in May (Ribeirão Preto Region), and one in July (Itapecerica da Serra Region). Epidemiologic, ecologic, and serologic surveys were conducted among case contacts, area residents, and captured rodents in five locations within the State of São Paulo in June of 1998. Six (4.8%) of 125 case contacts and six (5.2%) of 116 area residents had IgG antibody to Sin Nombre virus (SNV) antigen. No case contacts had a history of HPS-compatible illness, and only one area resident reported a previous acute respiratory illness. A total of 403 rodents were captured during 9 nights of trapping (1969 trap nights). All 27 rodents that were found to be positive for IgG antibody to SNV antigen were captured in crop border and extensively deforested agricultural areas where four of the 1998 HPS case-patients had recently worked. The IgG antibody prevalence data for rodents suggest that Bolomys lasiurus and perhaps Akodon sp. are potential hantavirus reservoirs in this state of Brazil.

Value of morphological criteria in diagnosing cervical HPV lesions confirmed by in situ hybridization and hybrid capture assay

The present study evaluated the value of morphological criteria (binucleation, multinucleation, koilocytosis, spindle koilocytes, abnormal mitosis and dyskeratosis) in the diagnosis of cervical human papillomavirus (HPV) lesions confirmed by in situ hybridization (ISH) and hybrid capture (HC) assay. Colposcopic punch biopsies from a series of 138 women with abnormal Pap smears were examined on light microscopy and in situ hybridization (DAKO widespectrum cocktail probe) for HPV-induced morphological changes and HPV DNA, respectively. Cervical swabs were analyzed for HPV DNA of the oncogenic types using Hybrid Capture. CIN 2 and CIN 3 were found in 44 biopsies, CIN 1 in 62, and no evidence of HPV in 32 cases. HPV was detected by ISH in 51/138 (37%) cases and by HC in 66/138 (48%) lesions. With both tests, HPV DNA detection increased parallel with lesion severity, up to 70% and 59% in CIN 2/3 by HC and ISH, respectively OR 4.6 (1.7-12.1) and 10.1 (3.0-33.8). Among the histological criteria, multinucleation, binucleation and abnormal mitoses were significantly associated with HPV DNA detection. Multinucleation proved to be the strongest predictor of HPV DNA-positivity. Binucleation, abnormal mitosis, koilocytosis and spindle koilocytes were also reliable criteria of HPV lesions. Minor nuclear atypia, and "mild koilocytosis" were of no value in making this diagnosis.

Morphological diagnosis of HPV lesions and cervical intraepithelial neoplasia (CIN) is highly reproducible

PURPOSE

to assess the value of individual histological criteria in the diagnosis of cervical HPV lesions.

METHODS

138 women referred for colposcopic evaluation (due to abnormal PAP smears) were subjected to cervical punch biopsy. The biopsies were classified as no HPV lesion, CIN 1, or CIN 2-3 by two observers independently. Kappa tests were used for interobserver agreement of the diagnosis. The presence of binucleation, multinucleation, abnormal mitosis. koilocytosis, spindle koilocytosis and dyskeratosis was similarly assessed.

RESULTS

the Kappa statistic was 0.638 (CI 95% 0.533-0.743), showing substantial inter-observer agreement. Abnormal mitosis and multi-nucleation were the two most powerful discriminators between CIN 2-3 and CIN 1. Koilocytosis proved to be the single most powerful discriminator between CIN 1 lesions and non-HPV lesions.

CONCLUSION

the results advocate the use of histology as the gold standard in diagnosing cervical precancerous lesions. The classical criteria can be also used to differentiate low-grade lesions, which has practical implications by avoiding the unnecessary treatment of minor abnormalities.

A polymorphism in endostatin, an angiogenesis inhibitor, predisposes for the development of prostatic adenocarcinoma

We have performed association studies between a novel coding single nucleotide polymorphism (D104N) in endostatin, one of the most potent inhibitors of angiogenesis, and prostate cancer. We observed that heterozygous N104 individuals have a 2.5 times increased chance of developing prostate cancer as compared with homozygous D104 subjects (odds ratio, 2.4; 95% confidence interval, 1.4-4.16). Modeling of the endostatin mutant showed that the N104 protein is stable. These results together with the observation that residue 104 is evolutionary conserved lead us to propose that: (a) the DNA segment containing this residue might contain a novel interaction site to a yet unknown receptor; and (b) the presence of N104 impairs the function of endostatin.

Aggressive metastatic follicular thyroid carcinoma with anaplastic transformation arising from a long-standing goiter in a patient with Pendred's syndrome

In this article we describe detailed pathological and molecular genetics studies in a consanguineous kindred with Pendred's syndrome. The index patient was a 53-year-old female patient with congenital deafness and goiter. Her parents were first-degree cousins. She had a large goiter (150 g) that had been present since childhood. One of her sisters and a niece are also deaf and have goiter as well. The presence of Pendred's syndrome was confirmed by a positive perchlorate test and the demonstration of a Mondini malformation. Thyroid function tests (under levothyroxine [LT4] therapy) were in the euthyroid range with a thyrotropin [TSH] level of 2.8 microU/mL (0.2-3.2), a serum total thyroxine (T4) of 90 nmol/L (54-142), and a serum total triiodothyronine (T3) of 2.7 nmol/L (0.8-2.4). Total thyroidectomy was performed, and the mass in the right lobe was found to have invaded adjacent tissues. The histopathological findings were consistent with a follicular carcinoma with areas of anaplastic transformation and lung metastasis. The patient was treated twice with 100 mCi 131iodine (3,700 MBq) and received suppressive doses of LT4. Postoperatively, the serum thyroglobulin (Tg) levels remained markedly elevated (2,352 to 41,336 ng/mL). The patient died of a sudden severe episode of hemoptysis. Sequence analysis of the PDS gene performed with DNA from the two relatives with Pendred's syndrome revealed the presence of a deletion of thymidine 279 in exon 3, a point mutation that results in a frameshift and a premature stop codon at codon 96 in the pendrin molecule. We concluded that prolonged TSH stimulation because of iodine deficiency or dyshormonogenesis in combination with mutations of oncogenes and/or tumor suppressor genes, may result in the development of follicular thyroid carcinomas that undergo transformation into anaplastic cancers. It is likely that these pathogenetic mechanisms have been involved in the development of aggressive metastatic thyroid cancer in this unusual patient with Pendred's syndrome.

Detection of human parvovirus B19 in a patient with hepatitis

Parvovirus B19 has been associated by some investigators with cases of severe hepatitis. The aim of the present study was to determine the presence of active parvovirus B19 infection among 129 Brazilian patients with non-A-E hepatitis. The patients were assayed for antibodies against parvovirus B19, IgM class, by ELISA. In IgM-positive cases, parvovirus B19 DNA was assayed by PCR in serum and liver tissue and parvovirus VP1 antigen in liver tissue was assayed by immunohistochemistry. Antibodies against parvovirus B19, IgM class, were detected in 3 (2.3%) of 129 patients with non-A-E hepatitis. Previous surgery and blood transfusions were reported by these 3 patients. One patient was a 56-year-old female with severe hepatitis, with antimitochondrial antibody seropositivity and submassive necrosis at liver biopsy, who responded to corticosteroid therapy. Strong evidence for active parvovirus B19 infection was found in this patient, with parvovirus B19 DNA being detected by PCR in liver tissue. Furthermore, parvovirus VP1 antigen was also detected in liver tissue by immunohistochemistry. The other two IgM-positive patients were chronic hepatitis cases, but active infection was not proven, since neither viral DNA nor antigen were detected in their liver tissues. This and other reports suggest a possible relation between parvovirus B19 infection and some cases of hepatitis.

Serious adverse events associated with yellow fever 17DD vaccine in Brazil: a report of two cases

BACKGROUND

The yellow fever vaccine is regarded as one of the safest attenuated virus vaccines, with few side-effects or adverse events. We report the occurrence of two fatal cases of haemorrhagic fever associated with yellow fever 17DD substrain vaccine in Brazil.

METHODS

We obtained epidemiological, serological, virological, pathological, immunocytochemical, and molecular biological data on the two cases to determine the cause of the illnesses.

FINDINGS

The first case, in a 5-year-old white girl, was characterised by sudden onset of fever accompanied by headache, malaise, and vomiting 3 days after receiving yellow fever and measles-mumps-rubella vaccines. Afterwards she decompensated with icterus and haemorrhagic signs and died after a 5-day illness. The second patient-a 22-year-old black woman-developed a sore throat and fever accompanied by headache, myalgia, nausea, and vomiting 4 days after yellow fever vaccination. She then developed icterus, renal failure, and haemorrhagic diathesis, and died after 6 days of illness. Yellow fever virus was recovered in suckling mice and C6/36 cells from blood in both cases, as well as from fragments of liver, spleen, skin, and heart from the first case and from these and other viscera fragments in case 2. RNA of yellow fever virus was identical to that previously described for 17D genomic sequences. IgM ELISA tests for yellow fever virus were negative in case 1 and positive in case 2; similar tests for dengue, hantaviruses, arenaviruses, Leptospira, and hepatitis viruses A-D were negative. Tissue injuries from both patients were typical of wild-type yellow fever.

INTERPRETATION

These serious and hitherto unknown complications of yellow fever vaccination are extremely rare, but the safety of yellow fever 17DD vaccine needs to be reviewed. Host factors, probably idiosyncratic reactions, might have had a substantial contributed to the unexpected outcome.

Relevance of the rates of PCNA, Ki-67 and p53 expression according to the epithelial compartment in cervical lesions

In order to assess further biological evidence for similarities among the "diagnostic classes" of cervical lesions, which are now a matter of international discussion in the search for a uniform classification, the purpose of this study was to characterize the immunoexpression of cell proliferation markers (proliferating cell nuclear antigen, PCNA and Ki-67) and protein p53. Each marker was individually quantified in basal, intermediate, and superficial epithelial compartments presenting chronic cervicitis (CC) accompanied by the cytopathic effects of infection by human papillomavirus (CCHPV) or not (CC), as well as in cervical intraepithelial neoplasia (CIN) grades I, II, and III. A total of 100 patients were evaluated and the positive nuclei were counted separately, including all extensions of the available epithelium. The percentage of PCNA- and Ki-67-positive cells increased with increasing grade of the cervical lesions, although PCNA immunoreactivity was always greater than the immunoreactivity observed with Ki-67 antigen. The immunoexpression of p53 protein was found to be weak, with no remarkable behavior in any specific "diagnostic class". The differences in cell proliferation markers found herein further emphasize the progressive loss of epithelial layer organization in the course of the development of preneoplastic changes in cervical squamous epithelium. Furthermore, difficulties in morphologically distinguishing "borderline lesions" persist when cell cycle markers are studied, further supporting the suggestion to consider the lesions of CCHPV and CIN I together as only one diagnostic class. Conversely, the different immune profile found between CIN II and III further supports the validity of the subdivision of CIN into three groups.

Paragangliomas of the head and neck: clinical, morphological and immunohistochemical aspects

CONTEXT

Protein marker positivity can assist in the definition of the therapeutic approach towards head and neck paragangliomas. The establishment of the therapeutic approach should incorporate the results of such an investigation.

OBJECTIVE

To establish criteria for benignity and malignancy of vagal and jugular-tympanic paragangliomas, via the study of the relationships of sex, age, tumor size, duration of complaints, site, family history, presence of metastases, treatment, histological architecture and cell type with the immunohistochemical reactions to S100 protein, chromogranin and AgKi67.

DESIGN

A retrospective study of histological and clinical records.

SETTING

The Heliópolis and Oswaldo Cruz tertiary general hospitals, São Paulo.

SAMPLE

8 cases of head and neck paragangliomas.

MAIN MEASUREMENTS

Determination of degree of positivity to paragangliomas via immunohistochemical reactions.

RESULTS

1). The protein markers for the principal cells (AgKi67 and chromogranin) were sensitive in 100% of the tumors when used together. 2). S100 protein was well identified in the cytoplasm and nucleus of sustentacular cells and underwent reduction in the neoplasias.

CONCLUSIONS

Chromogranin was proven to be a generic marker for neuroendocrine tumors; S100 protein was positive in all 8 cases and the AgKi67 had low positivity in all cases.

Differential reactivity for galectin-3 in Hürthle cell adenomas and carcinomas

Hürthle cell carcinomas behave as the most aggressive variant of differentiated thyroid carcinoma of follicular origin, with frequent recurrences and higher morbidity. Its differential diagnosis with Hürthle cell adenoma remains a problem for the clinician and for the pathologist. The vertebrate lectins, galectin-1 and galectin-3 have been implicated in the regulation of cellular growth, differentiation, and malignant transformation in thyroid neoplasms. Galectin-3, a beta-galactoside binding protein, has been recently found to be highly expressed in papillary and follicular carcinomas. The current study was undertaken to investigate immunohistochemical reactivity for galectin-3 of thyroid specimen tissues with Hürthle cell adenomas (n = 14) and carcinomas (n = 17), follicular (n = 14) and papillary (n = 11) carcinomas, colloid goiter (n = 30), Hashimoto's thyroiditis (n = 11), follicular adenoma (n = 9), and normal thyroid tissues (n = 18). Follicular (78.5%) and papillary (82.0%) carcinomas were frequently reactive for galectin-3, more often when some H rthle cells were present. There was no galectin-3 immunostaining in any of the specimens from Hashimoto's thyroiditis, colloid goiters or normal thyroid samples, whereas only one case of follicular adenoma was found positive (11.1%). By contrast, galectin-3 immunostaining in Hürthle cell carcinomas was significantly higher (59%) than in H rthle cell adenomas (7.1), p < 0.05). These results suggest that galectin-3 may potentially serve as a marker in difficult differential diagnosis cases involving Hürthle cell adenomas and Hürthle cell carcinomas.

Uncommon histopathological findings in fatal measles infection: pancreatitis, sialoadenitis and thyroiditis

AIMS

We report uncommon histopathological findings in fatal measles infection.

METHODS AND RESULTS

We describe the autopsies of four patients who died during a measles outbreak in São Paulo, Brazil, in 1997. Two of the patients were children receiving chemotherapy for non-Hodgkin's lymphoma, one was an adult with acquired immunodeficiency syndrome (AIDS) and the fourth was an apparently healthy woman. All patients had their deaths attributed to measles pneumonia. The autopsies revealed extensive giant cell pneumonia and diffuse alveolar damage, severe acute pancreatitis, necrotizing sialoadenitis and thyroiditis due to measles. Measles antigen was detected in lung tissue using a monoclonal anti-measles antibody.

CONCLUSIONS

: Pancreatitis, thyroiditis and sialoadenitis are not previously reported histopathological findings in measles infection. Pancreatitis is a potentially severe complication and should be considered when treating patients with atypical measles.

Metalloproteinase-9 immunoexpression and angiogenesis in thyroid follicular neoplasms: relation to clinical and histopathologic features

BACKGROUND

Thyroid follicular neoplasms (adenoma and carcinoma) may pose considerable difficulties to the differential diagnosis. Because such a distinction is not possible at fine-needle aspiration, surgery is often necessary. Clinical information such as age, sex, and node size is important in case of suspected carcinoma. Follicular carcinoma is characterized by capsular invasion, vascular invasion, and metastatic dissemination mainly by the hematogenic pathway. This invasion depends on collagen degradation in capsule and in subendothelial basement membrane. Collagen degradation has been widely researched in the angiogenesis process and in the hematogenic dissemination mechanism. In this study, we performed clinical and histopathologic assessment of 74 follicular neoplasms, as well as immunohistochemical reactions for CD-34 protein to estimate angiogenesis and for metalloproteinase-9, an enzyme that degrades type IV collagen.

METHODS

The research was carried out retrospectively in 74 patients who had surgery and were followed up at HC-FMUSP and IBCC. Clinical, histologic, and immunohistochemical variables were compared among the groups of follicular neoplasms and a control group of 36 patients with colloid goiter.

RESULTS

No significant statistical difference was found between patients with follicular adenoma and thyroid follicular carcinoma concerning sex (p =.092), age (p =.098), thyroid node size (p =.426), vascularization (p =.388), and immunostaining intensity for metalloproteinase-9 (p =.055). The proportion of immunoreactive cells for metalloproteinase-9 in follicular carcinoma cases was higher than that observed in follicular adenoma cases (p <.001). Patients in more advanced stages of carcinoma were more than 45 years old (p =.006), presented extensive invasion (p <.001), had less vascularization (p =.046), and a had higher proportion of immunoreactive cells for metalloproteinase-9 (p <.001).

CONCLUSIONS

The proportion of immunoreactive cells for metalloproteinase-9 in follicular carcinoma was higher than that observed in follicular adenoma, with a significant statistical difference (p <.001). This method must be developed to apply in material obtained by fine-needle aspiration to differentiate follicular adenoma from carcinoma.

Metalloproteinase-9 immunoexpression and angiogenesis in thyroid follicular neoplasms: relation to clinical and histopathologic features

BACKGROUND

Thyroid follicular neoplasms (adenoma and carcinoma) may pose considerable difficulties to the differential diagnosis. Because such a distinction is not possible at fine-needle aspiration, surgery is often necessary. Clinical information such as age, sex, and node size is important in case of suspected carcinoma. Follicular carcinoma is characterized by capsular invasion, vascular invasion, and metastatic dissemination mainly by the hematogenic pathway. This invasion depends on collagen degradation in capsule and in subendothelial basement membrane. Collagen degradation has been widely researched in the angiogenesis process and in the hematogenic dissemination mechanism. In this study, we performed clinical and histopathologic assessment of 74 follicular neoplasms, as well as immunohistochemical reactions for CD-34 protein to estimate angiogenesis and for metalloproteinase-9, an enzyme that degrades type IV collagen.

METHODS

The research was carried out retrospectively in 74 patients who had surgery and were followed up at HC-FMUSP and IBCC. Clinical, histologic, and immunohistochemical variables were compared among the groups of follicular neoplasms and a control group of 36 patients with colloid goiter.

RESULTS

No significant statistical difference was found between patients with follicular adenoma and thyroid follicular carcinoma concerning sex (p =.092), age (p =.098), thyroid node size (p =.426), vascularization (p =.388), and immunostaining intensity for metalloproteinase-9 (p =.055). The proportion of immunoreactive cells for metalloproteinase-9 in follicular carcinoma cases was higher than that observed in follicular adenoma cases (p <.001). Patients in more advanced stages of carcinoma were more than 45 years old (p =.006), presented extensive invasion (p <.001), had less vascularization (p =.046), and a had higher proportion of immunoreactive cells for metalloproteinase-9 (p <.001).

CONCLUSIONS

The proportion of immunoreactive cells for metalloproteinase-9 in follicular carcinoma was higher than that observed in follicular adenoma, with a significant statistical difference (p <.001). This method must be developed to apply in material obtained by fine-needle aspiration to differentiate follicular adenoma from carcinoma.

Predictive factors for response to lamivudine in chronic hepatitis B

BACKGROUND

Lamivudine has been shown to be an efficient drug for chronic hepatitis B (CHB) treatment.

AIM

To investigate predictive factors of response, using a quantitative method with high sensitivity.

METHODS

We carried out a prospective trial of lamivudine in 35 patients with CHB and evidence for viral replication, regardless to their HBeAg status. Lamivudine was given for 12 months at 300 mg daily and 150 mg thereafter. Response was considered when DNA was undetectable by PCR after 6 months of treatment. Viral replication was monitored by end-point dilution PCR. Mutation associated with resistance to lamivudine was detected by DNA sequencing in non-responder patients.

RESULTS

Response was observed in 23/35 patients (65.7%) but only in 5/15 (33.3%) HBeAg positive patients. Only three pre-treatment variables were associated to low response: HBeAg (p = 0.006), high viral load (DNA-VHB > 3 x 10(6) copies/ml) (p = 0.004) and liver HBcAg (p = 0. 0028). YMDD mutations were detected in 7/11 non-responder patients.

CONCLUSIONS

HBeAg positive patients with high viral load show a high risk for developing drug resistance. On the other hand, HBeAg negative patients show a good response to lamivudine even with high viremia.

Adrenocortical carcinoma: clinical and laboratory observations

BACKGROUND

The clinical features and natural history of adrenocortical carcinoma are highly dependent on the type of center reporting their experience. Observations from oncology services suggest a high incidence of nonfunctioning tumors, whereas reports from endocrine clinics emphasize excessive corticoid and androgen production in the majority of tumors. The incidence rate and natural history of childhood adrenal carcinoma generally has been under emphasized.

METHODS

Over the past 17 years, the authors have evaluated and treated 47 patients with adrenocortical carcinoma referred to the University of Sao Paulo, 22 of whom were children.

RESULTS

There is a bimodal age incidence of adrenal carcinoma, with the disease peaking in the first and fourth decades of life. Childhood adrenal carcinoma is characterized by a high rate of incidence of virilization, marked overproduction of androgens, and a less aggressive clinical course, and appears to be more amenable to surgical and other therapeutic modalities. By contrast, adrenocortical carcinoma occurring in adults presents more commonly as a mixed Cushing and virilizing syndrome, with overproduction of corticoids and androgens and a far more aggressive clinical course, leading to rapid death within months or years. Nonfunctioning adrenocortical carcinoma is less common; it generally occurs in older adults and exhibits a rapid downhill course. Modern day imaging methods have improved the diagnosis and staging of adrenal carcinoma greatly. In the authors' experience, the histologic criteria of Weiss appeared to predict tumor prognosis most accurately, whereas immunologic markers, cytoskeletal markers, DNA ploidy, cell phase markers, and oncogenic probes have yielded inconsistent results to date. Surgical removal of a localized tumor remains the best hope for long term survival. Medical therapy with mitotane and its successors in patients with Stage III or IV (MacFarlane system as modified by Sullivan et al.) disease appear to have added little to longevity or quality of life.

CONCLUSIONS

When diagnosed in children, adrenal carcinoma is associated with virilism and a less aggressive natural history; however, when it occurs in adults, the disease presents more commonly as a mixed Cushing-virilizing syndrome and has a virulent course. The Weiss histologic criteria appear to correlate best with disease prognosis, but other histochemical, cell cycle, and genetic markers have not, to date, aided in disease management.

[Frequency of adenocarcinomas in serous effusions]

BACKGROUND

Metastatic adenocarcinomas in effusions are frequently observed. Cytologic diagnosis of adenocarcinoma is often precise; unfortunately, the classification of the primary site is not possible in a great number of cases. The scope of this study was to report the frequency of adenocarcinomas in effusions according to the primary site.

MATERIAL

We studied 2317 sequential cases: 1146 pleural effusions (943 women and 203 men), 1168 ascitic (727 women and 441 men), and 3 pericardial (2 women and 1 men).

METHOD

Retrospective analysis of the records of the patients and correlations of the data of clinical follow up and morphological findings.

RESULTS

The primary sites more frequently seen in pleural cavity were: breast (N = 586--51.1%), lung (N = 185--16.1%: 102 men and 83 women), and ovary (N = 124--10.8%); in ascites: stomach (N = 473--40.5%: 300 men and 173 women), ovary (N = 306--26.2%) and breast (N = 83--7.1%). Regarding only the samples of malignant effusions we observed 555 in pleural cavity: breast (N = 288--51.9%), lung (N = 92, 16.6%: 45 men and 47 women) and ovary (N = 54, 9.7%). In ascites we reported: ovary (N = 205--37.9%), stomach (N = 202--37.3%: 119 men and 83 women) and breast (N = 31--6.8%). In 47 pleural effusions (8.5%) and 37 ascites (6.8%), the original site of the neoplasia remained undetermined.

CONCLUSION

The knowledge of the relative frequencies, associated with clinical information, can be helpful in the selection of further investigation for the metastatic adenocarcinomas.

Serodiagnosis of hepatitis C virus. Effect of new evaluation of cutoff values for enzyme-linked immunosorbent assay in Brazilian patients

With the goal of reducing false-positive results in enzyme-linked immunosorbent assay (ELISA) serodiagnosis of hepatitis C virus in clinical practice, a study was undertaken to establish better cutoff values. We examined 277 serum samples from patients with hepatitis (non-A, non-B; B; autoimmune); subjects with antinuclear antibodies or rheumatoid factor, anticytomegalovirus or Epstein-Barr virus IgG or IgM antibodies, or parasitic disease (Chagas disease, leishmaniasis); and healthy volunteers. Concordant positive results in 2 different immunoblot assays in 250 samples were taken as indicative of true-positive, and when negative, of absence of infection. Reactivity in 3 ELISA tests were evaluated for the manufacturer recommended cutoff (CO) and for 2CO, 3CO, and 4CO; and corresponding sensitivity and specificity were calculated for single or combined pairs of ELISA tests. Although CO is adequate for blood bank screening, because it provides maximal sensitivity, the frequently observed false-positive results could be significantly reduced by increasing the cutoff value to 2CO, with no significant loss in sensitivity either in relation to pairs of immunoenzymatic tests or to a single ELISA.

Immunocytochemistry applied to aspiration biopsy cytology. Diagnostic contribution in 100 cases of previously stained, routine specimens

OBJECTIVE

To assess the contribution of immunocytochemistry (ICC) to aspiration biopsy cytology (ABC), in a diagnostic context, on routine, previously stained cytologic specimens.

STUDY DESIGN

Among 5,221 consecutive cases of ABC, 5.3% were subjected to ICC in the clinical-morphologic context. One hundred of these cases, with a final clinical and histopathologic diagnosis, were studied to determine the contribution of this ancillary technique to the final cytologic diagnosis. All cases had histopathologic study and prospective ICC, performed on usual smears, alcohol fixed and previously stained by the Papanicolaou technique, and were subjected to an avidinbiotin-peroxidase complex method.

RESULTS

ICC was contributory in 82% of cases. The contribution of ICC to ABC of lymphoid tissue, thyroid and related organs, soft tissue and miscellaneous cases was, respectively, 84% (39 cases), 88% (26), 72% (18) and 76% (17). ICC was noncontributory in 18 cases, due mainly to misleading interpretation (6%), uncharacteristic profile (5%) and inconclusive immunostain (7%).

CONCLUSION

ICC could be successfully applied in routine ABC specimens since the usually investigated antigenic determinants are preserved, allowing previous morphologic study and screening of the smears. The principal contribution of ICC applied to lymph nodes, thyroid and soft tissue aspirates was, respectively, confirmation of metastatic neoplasms, differential of follicular versus C-cell proliferation and assessment of mesenchymal lineages.

Acid secretory response in the late follow-up of proximal gastric vagotomy for duodenal ulcer without Helicobacter pylori eradication

BACKGROUND/AIMS

The profile of acid secretory responses was studied in 20 patients who had had proximal gastric vagotomy (PGV) surgery performed 11-22 years previously in order to treat duodenal ulcers (DU). The presence of Helicobacter pylori was detected in all of the patients.

METHODOLOGY

The recurrence of DU was diagnosed in 10 patients and the other 10 remained without recurrence during the follow-up period. The control groups included 10 DU patients with refractory responses to H2 receptor antagonists and 10 "normal" subjects. Both control groups had untreated Helicobacter pylori infection. Measures of 1) basal acid output, 2) acid output for 30 min under continuous i.v. infusion of 0.2 ug/kg/h of pentagastrin acid, and 3) the response for 30 and 60 min after starting a sham feeding, modified by the "chew and spit" technique under simultaneous i.v. infusion of 0.2 ug/kg/h of pentagastrin were performed. Serum gastrin was measured during fasting and at sham feeding. The densities of the gastrin cells of antrum and duodenum were estimated by morphometric counting.

RESULTS

Both basal output and acid response to sham feeding plus pentagastrin infusion were higher in the DU controls and DU recurrence patients. The response to pentagastrin infusion did not show any discriminant value. Fasting serum gastrin values increased after PGV, either with or without DU recurrence. Gastrin cell hyperplasia was not demonstrated in any of these groups.

CONCLUSIONS

The secretory profile of patients with both late DU recurrence after PGV and Helicobacter pylori infection lies between DU patients refractory to the H2 receptor antagonist approach and those free of DU recurrence after PGV--both of them with current Helicobacter pylori infection. The characteristic pattern of late DU recurrence after PGV and untreated Helicobacter infection is that of increased basal acid output and higher acid secretion responsiveness to sham feeding plus pentagastrin in the presence of higher serum levels of gastrin.

Cigarette smoking and high-risk HPV DNA as predisposing factors for high-grade cervical intraepithelial neoplasia (CIN) in young Brazilian women

BACKGROUND

This cross-sectional study was designed to evaluate the role of cigarette smoking and high-risk HPV types as risk factors of CIN 2 and 3 in young, sexually active Brazilian women.

MATERIALS AND METHOD

A series of 100 consecutive women with abnormal Pap smears were recruited, subjected to colposcopy, punch biopsy, and questionnaire for their social, sexual and reproductive factors. Of these, 77 women between 20 and 35 years of age (median 26.5 years) with biopsy-confirmed CIN 1 or CIN 2 and 3, were enrolled in this study. Representative samples from the exocervix and endocervix were obtained for HPV testing with the Hybrid Capture HPV-DNA assay, including the probes for the oncogenic HPV types (16, 18, 31, 33, 35, 45, 51, 52 and 56).

RESULTS

The overall rate of CIN 2 and 3 was 23/77 (29.8%). The women with CIN 1, 2 and 3 did not differ from each other with regard to their age, race, schooling, marital status, lifetime number of sexual partners, age at first intercourse, use of oral contraceptives, or parity. However, current cigarette smoking was strongly associated with CIN 2 and 3 (p<0.001), and among smokers, the risk of high-grade CIN increased in parallel with the time of exposure (years of smoking) (p=0.07). HPV-DNA of the oncogenic types was detected in 43 (56%) women, the risk of being HPV DNA-positive was significantly higher in CIN 2 and 3 as compared with CIN 1 (p=0.037). Importantly, the prevalence of high-risk HPV types was significantly higher in cigarette smokers than in non-smokers (p=0.046).

CONCLUSIONS

The results indicate that the severity of CIN lesions was clearly related to two fundamental risk factors: 1) high-risk HPV types, and 2) current cigarette smoking. These two risk factors were closely interrelated in that the high-risk HPV types were significantly more frequent in current smokers than in non-smokers, suggesting the possibility of a synergistic action between these two risk factors in cervical carcinogenesis.

Primary malignant epithelial tumors of the liver in children: a study of DNA content and oncogene expression

Primary malignant epithelial tumors of the liver (PMETL) are rare in the pediatric age group, and very little is known about their biology as compared with adult tumors. The prognostic value of the DNA contents measured by image analysis and expression of oncogene c-erb2 and tumor suppressor gene p53 were studied in 30 cases of PMETL in children, including 24 with hepatoblastomas (HB) and 6 with hepatocellular carcinomas (HCC). p53 overexpression was detected in 12 out of 26 cases (46.0%), or in 3 of 5 HCC and 9 of 21 HB cases. A relatively high concordance of staining was observed with the two antibodies used (clone DO7, Dako and clone DO1, Santa Cruz Biotechnology). c-erb-B2 did not yield the characteristic membrane staining in any of the 27 cases in which reliable staining was obtained. However, 1 out of 4 patients with HCC and 1 of 23 with HB revealed strong granular cytoplasmic staining in several neoplastic cells. Interestingly, these were two of the three aneuploid multiploid cases. DNA histograms of 13 out of 29 cases (54.8%) were classified as DNA aneuploid (5/6 HCC and 8/23 HB): nine were hyperdiploid, one was hypodiploid (1HB), and three were multiploid (2HB and 1HCC). In the HB group, DNA aneuploidy was strongly associated with embryonal histological areas, suggesting that a disturbance in the process of cell differentiation is associated with marked genetic aberrations. Only the group of HB was submitted to univariate analysis of survival by the Kaplan-Meier method for age (< 24 months vs. > or = 24 months), sex, preoperative chemotherapy (yes vs. no), residual disease (metastasis, and/or unresectable tumor), p53 expression by immunohistochemistry (positive vs. negative), and DNA ploidy (diploid vs. aneuploid). Only residual disease at the time of diagnosis (P < 0.017) and preoperative chemotherapy (0.030) were found to be negatively correlated with biological behavior, estimated as overall survival. DNA aneuploidy tumors (P < 0.125) and male patients (P = 0.123) showed a trend toward a more aggressive clinical behavior, although the difference was not statistically significant. Combining DNA ploidy and residual disease, patients were categorized into three groups: group I, patients with no adverse prognostic factors, i.e., diploid tumors without residual disease; group II, patients with only one adverse prognostic factor, i.e., aneuploid tumor or residual disease; and group III, patients with both adverse factors, aneuploid tumors and residual disease at time of diagnosis. A log-rank test comparing the three survival curves showed a statistically significant difference between them (P < 0.003). Although the series of cases is small, the results of this study highlight the importance of including DNA ploidy in the protocols designed for HB in children by international cooperative groups.

[Quality assurance in cytopathology: aspects of the cytohistological correlation]

The cytohistologic diagnosis concordance of the cervix-uterine lesions was evaluated and the discordances are discussed.

PURPOSE

To evaluate the level of cytohistological diagnosis agreement in the Pathology Division of the Adolfo Lutz Institute and enhance parameters of quality assurance system developed in this institution.

METHODS

The authors retrospectively evaluated 157 pairs of cytologyhistology consecutive cases from the files the Adolfo Lutz Institute (Division of Pathology).

RESULTS

Agreement was found in 119 cases (75.8%); in the remaining cases cytologic diagnosis were higher than histology in 11 lesions (7.0%) and lower in 27 (17.2%). We also observed that in 5 cases previously diagnosed as inflammatory, 2 of them were reclassified as CIN 1; after revision, the others remained as inflammatory even though they had a histological diagnosis of CIN.

CONCLUSION

These results showed the role of cytohistological correlation to the quality assurance system of cytological diagnosis and also stressed the importance of taking the cervical scrapes with accurate care to avoid diagnostic discrepancies.

Cytomorphologic evidence of human papillomavirus infection in smears from the irradiated uterine cervix

OBJECTIVE

To report the cytomorphologic evidence of human papillomavirus (HPV) infection in cervical smears from women treated with radiotherapy for carcinoma of the uterine cervix.

STUDY DESIGN

From January 1986 to December 1993, 32 cervical cytologic smears (CCSs) from women who had received radiotherapy (Rtx) for squamous cell cervical carcinoma at A.C. Camargo Cancer Hospital were selected for study due to the presence of signs of HPV infection. Review of the files of these patients showed 22 additional samples, which we included in this study. The avidinbiotin-immunoperoxidase technique was performed on previously stained slides using polyclonal rabbit antibovine papillomavirus type 1 to confirm the HPV infection.

RESULTS

Positive reactions were found in 18 cases (27 samples), mainly in cells with classic koilocytotic features, but also in epithelial cells that lacked cytopathic effects. Only one case, a biopsy from a verrucous lesion observed after Rtx, was found to be positive for HPV 6/11 DNA by in situ hybridization.

CONCLUSION

Cytologic and immunohistochemical positivity for HPV, as well as the reaction with a HPV 6/11 DNA probe, strongly suggested that HPV infection was acquired or expressed after radiotherapy. Further studies are needed to assess the mechanisms responsible for such an association.

Adenocarcinoma in females detected in serous effusions. Cytomorphologic aspects and immunocytochemical reactivity to cytokeratins 7 and 20

OBJECTIVE

To investigate the usefulness of assessing the immunoreactivity of cytokeratins 7 (CK7) and 20 (CK20) as well as several cytomorphologic parameters in effusions with metastatic adenocarcinomas in the search for the primary site of the tumor.

STUDY DESIGN

From the files of the Pathology Department, A. C. Camargo Hospital, we studied cytologic smears from 73 metastatic adenocarcinomas originally from the breast, 63 from the ovary, 40 from the lung and 32 from the stomach, looking for morphologic parameters that could have discriminant potential in suggesting the primary site in a routine situation, including intranuclear inclusions, prominent nucleoli, mitosis, signet-ring cells, psammoma bodies, nuclear crease, binucleation and multinucleation, papillary features, acinar profile (including ball cells) and single cells. Immunoreactions were performed with monoclonal antibodies to CK7 (OV-TL 12/30) and CK20 (Ks 20.8) and included morphologic analysis. Both analyses were studied in a blind fashion regarding the primary site of the tumors.

RESULTS

Positivity ratios for breast, ovary, stomach and lung cases were 67.6%, 63.5%, 29.7% and 45.5%, respectively, for CK7 and 17.2%, 15.8%, 13.5% and 32.2%, respectively, for CK20. Discriminant analysis of morphologic and immunocytochemical parameters had an error rate of 42.9% in recognizing the primary site and a Wilk's lambda of .7290.

CONCLUSION

The more efficient parameter with discriminant function was the papillary appearance showed by CK7, which should be used in further studies with a similar scope. The set of parameters used in this study were insufficient to discriminate the primary site of female adenocarcinomas in effusions with significant accuracy.

Image analysis of nuclear/cytoplasmic ratio in cervical smears to discriminate three grades of cervical intraepithelial neoplasia

OBJECTIVE

To suggest which system of cytologic classification (Bethesda System or World Health Organization [WHO]) of cervical lesions is more adequate for the Public Health Service of São Paulo State, Brazil, based on morphometric study with the Jandel Videoanalysis (JAVA) System.

STUDY DESIGN

The study comprised groups of typical smears: cervical intraepithelial neoplasia (CIN 1) separated into two subgroups: cytopathic effects of human papillomavirus associated or not with dyskaryosis, CIN 2 and CIN 3. The JAVA system of image analysis was used to determine the nuclear/cytoplasmic (N/C) ratio in abnormal cells from each group.

RESULTS

Significant differences were detected between the three grades of CIN and between the two subgroups of CIN 1.

CONCLUSION

Although image analysis is not applicable to large-scale population screening of cervical smears, its use in the present study favored the three-grade cytologic classification (WHO). In addition, the three-grade classification offers the clinician more options for treatment. Considering the clinical-laboratory characteristics of our public health service, the three-grade classification is more adequate.

Lung lesions in human leptospirosis: microscopic, immunohistochemical, and ultrastructural features related to thrombocytopenia

Lung fragments from 12 patients were collected immediately after death and studied by light and electron microscopy and by immunohistochemistry to describe the main morphologic and ultrastructural aspects of the lung and platelets in leptospirosis (Weil's syndrome), to search for the possibility of disseminated intravascular coagulation (DIC), and to assess the relationship between endothelial lesions and local platelet aggregation and the leptospiral antigen distribution, as well as its relationship with the intensity of the lesions. The immunohistochemical results for fibrin aggregates were positive in the lumen and/or on the vascular endothelium in nine cases and on the alveolar surface in seven cases, leading to the diagnosis of the adult respiratory distress syndrome in these seven cases. Test results for leptospiral antigen by immunohistochemistry were positive in eight cases with no direct relationship between antigen deposits in the pulmonary vascular endothelium and intensity of the lesions. The ultrastructural findings were uniform and constant. Capillary lesions were characterized by swelling of endothelial cells, an increase in pinocytotic vesicles, and giant dense bodies in the cytoplasm of these cells. No necrosis, rupture, nor exposed subendothelial collagen was observed outside the hemorrhagic areas, and the intercellular junctions were preserved. The lung involvement in severe human leptospirosis presents as hemorrhagic pneumopathy with septal capillary lesions that are the usual cause of death. The thrombocytopenia that was verified in 11 of 12 patients in our study seems to bear no relationship to DIC and seems to be determined by activation, adhesion, and aggregation of platelets to the stimulated vascular endothelium, with an amorphous electron-dense substance between the endothelial cells and the adherent platelets in places where the subendothelial collagen was not exposed.

Spontaneous hepatitis B surface antigen clearance in a long-term follow-up study of patients with chronic type B hepatitis. Lack of correlation with hepatitis C and D virus superinfection

We investigated the frequency of HBsAg clearance and the possible role of viral superinfection in a long-term follow-up of 184 patients with chronic hepatitis B (CHB). Our subjects were 184 patients with chronic hepatitis B and the follow-up was 12-216 months (mean 66.2 +/- 53.7 months). The investigative methods used were: immunoenzymatic assays for HBV, HCV, HDV, and HIV markers; polymerase chain reaction (PCR) for HBV DNA; and liver biopsy and immunoperoxidase. During the follow-up, 20 of the 184 patients cleared serum HBsAg. A comparison of patients with persistent HBsAg(group I) and of those who cleared this marker (group II) showed a significant difference in mortality (P = 0.002) between the two groups and a tendency to a more severe exacerbation (flare) in group II (P = 0.07). Antibodies to hepatitis C and D virus as well as antibodies to HIV were equally distributed in both groups. Thirteen patients (7.9%) from group I, but none from group II, subsequently developed hepatocellular carcinoma. These results suggest that the frequency of spontaneous clearance of HBsAg during chronic HBV infection is low. No determinant factor for the clearance was found, including the presence of liver cirrhosis. Serum HBV DNA was undetectable by PCR after clearance in 16 out of 17 patients.

Lactoferrin in thyroid lesions: immunoreactivity in fine needle aspiration biopsy samples

OBJECTIVE

Lactoferrin is an iron-binding protein that has been used for distinguishing normal from neoplastic conditions in many different tissues. In order to improve evaluation of thyroid lesions, we studied the lactoferrin immunoreaction in cytologic smears obtained by fine needle aspiration and in biopsy samples from primary neoplasms and from adenomatous goiter.

STUDY DESIGN

A retrospective study on fine needle aspiration cytology samples and corresponding available biopsies from thyroid lesions in patients examined at São Paulo County Hospital between 1982 and 1992, performed in order to evaluate lactoferrin immunoreactivity in morphologically well characterized samples from neoplastic and nonneoplastic lesions. Immunoperoxidase procedures were performed using monospecific polyclonal rabbit antihuman lactoferrin as a primary antibody and biotinylated goat antirabbit IgG as a secondary antibody. Amplification was performed with the avidin-biotin-peroxidase complex, and the color sign of the positive reactions was developed using a diaminobenzidine solution.

RESULTS

Lactoferrin was not detected in cytologic smears from goiters, whereas only one biopsy was slightly positive (1/21, or 4.76%). One smear from adenoma showed low positive staining (1/19, or 5.26%), which was present in 4 of 13 biopsies (30.77%) from adenoma. Papillary carcinomas were positive in 19 of 33 smears (57.58%) and in 100% of biopsies, whereas 31.25% (5/16) of follicular carcinoma smears were positive for lactoferrin, detected in all the biopsy samples.

CONCLUSION

Lactoferrin immunoreactivity was strongly associated with neoplastic proliferation and may be used as a useful auxiliary marker to distinguish malignant from benign thyroid lesions in cytologic smears and biopsy samples.

Trypanosoma cruzi strains and autonomic nervous system pathology in experimental Chagas disease

Lesions involving the sympathetic (para-vertebral ganglia) and para-sympathetic ganglia of intestines (Auerbach plexus) and heart (right atrial ganglia) were comparatively analyzed in mice infected with either of three different strain types of Trypanosoma cruzi, during acute and chronic infection, in an attempt to understand the influence of parasite strain in causing autonomic nervous system pathology. Ganglionar involvement with neuronal destruction appeared related to inflammation, which most of the times extended from neighboring adipose and cardiac, smooth and striated muscular tissues. Intraganglionic parasitism was exceptional. Inflammation involving peripheral nervous tissue exhibited a focal character and its variability in the several groups examined appeared unpredictable. Although lesions were generally more severe with the Y strain, comparative qualitative study did not allow the conclusion, under the present experimental conditions, that one strain was more pathogenic to the autonomic nervous system than others. No special tropism of the parasites from any strain toward autonomic ganglia was disclosed.

Demonstration of mycobacterial antigens in skin biopsies fron suspected leprosy cases in the absence of bacilli

Skin-biopsies from fifty-six patients suspected of early leprosy from Bahia State, Brazil, were examined histopathologically. The Fite-Faraco staining failed to demonstrate acid-fast bacilli in this material. The prominent features of the lesions were inflammation of the neurovascular bundles and sometimes inflammation of the skin appendages. The non-specific infiltrate was predominantly composed of histiocytes and lymphocytes. In 41 cases (73.2%) epidermal atrophy was also present. The avidin-biotin peroxidase technique was used with primary antibodies to detect bacillary antigens (anti-BCG serum) and nerve branches (anti-S-100 protein serum). Immunohistochemical detection of bacillary antigens using the anti-BCG serum was positive in 28 cases (50%). A positive staining for S-100 protein was observed in 40 cases (71.4%) in dendritic antigen-presenting cells of the skin. The detection of bacillary antigens, together with the clear demonstration of nerve bundles enhanced our capacity to fulfill morphologic criteria for the diagnosis of early leprosy. Our observations indicate that the use of immunohistochemical methods represent a useful tool for the early diagnosis of leprosy.

Frequency of epithelial giant cells in smears with Papillomavirus

We re-screened cytological smears from patients who presented Human Papillomavirus (HPV) infection detected morphologically in order to verify the frequency of associated giant epithelial cells, as recently mentioned in the literature. Our results demonstrated that 14 (13.7%) of 102 cases showed the giant epithelial cells, associated or not with macronmucleosis, bi or multinucleation. Epithelial giant cells showed a poor reaction to the avidin-biotin-peroxidase to the BPV-1 antigen. We conclude that epithelial giant cell is not a frequent cytologic feature in HPV, and the avidin-biotin-peroxidase study did not detect a marked expression of HPV late antigen.

Immunohistochemistry of medullary thyroid carcinoma and C-cell hyperplasia by an affinity-purified anti-human calcitonin antiserum

BACKGROUND

The diagnosis of medullary thyroid carcinoma (MTC) depends on the calcitonin immunohistochemistry. Familial MTC is associated with C-cell hyperplasia (CCH), whereas sporadic MTC is not. A specific and sensitive calcitonin immunohistochemistry is necessary for the diagnosis of MTC and CCH.

METHODS

An affinity-purified anti-calcitonin antiserum (APxCT) was used for immunohistochemistry of the thyroids of 15 patients with MTC. The thyroids of five patients with familial MTC were studied in detail, with each gland sectioned in 48 areas.

RESULTS

Between three and ten independent MTC were found in each thyroid, and CCH was found in all five patients (24.2%, varying from 8.4-56.3% of the 48 areas from each thyroid). MTC and CCH were localized mainly in the middle third and in the central axis of the thyroid lobes. They often were found together in the same area (in a total of 21 areas for the five thyroids sectioned in 48 areas) but ten areas with MTC did not have CCH, and 37 areas with CCH did not have MTC. In ten thyroids partially studied, CCH was indicated in three patients thought to have sporadic MTC. In two thyroids, with follicular and papillary carcinoma, a higher density of C-cells was found around the tumors, but disease was not characterized as CCH.

CONCLUSIONS

APxCT antiserum increased the immunohistochemical specificity and sensitivity. The distinction of the familial from the sporadic MTC requires a careful and extensive search of CCH. C-cells in high density may be found around follicular cell carcinomas, being a potential source of diagnostic error.

Leptospiral antigens in the liver of experimentally infected guinea pig and their relation to the morphogenesis of liver damage

In order to investigate the morphogenes of experimental leptospirosis by morphologic and immunohistologic methods, 24 guinea-pigs were inoculated intraperitoneally with L. interrogans serogroup Icterohaemorrhagiae. They were divided in 6 groups, sacrificed from the 1st to the 6th day of infection. Semiquantitative analyses of histopathological liver lesions were performed in 1 micron sections of tissue embedded in glycol-methacrylate. The distribution of leptospiral antigen (L. Ag) and its glycolipoprotein (GLP) was demonstrated by peroxidase-antiperoxidase on paraffin embedded tissue. Significant lesions appeared at the 4th day of infection, progressing to a peak on the 6th day. Inflammation was associated with injury of the portal triad. Liver cells showed either swelling or acidophilic degeneration and necrosis, together with loss of cell cohesion, leading to disarray of liver cell plates. Mitochondria were found progressively enlarged and irregularly distributed. L. Ag expression was parallel to the morphological changes. Portal distribution was significant at the 4th day and on later stages centrilobular localization became predominant. Spiral forms suggestive of intact leptospires were initially found but, chiefly at the 6th day, L. Ag was seen in granules, probably resulting from phagocytosis. GLP staining was similar to granular L. Ag in morphology, and distribution. Cytokeratin condensation was seen in liver cells with acidophilic necrosis and was marked in areas of disorganization of cell plates. Our findings lead us to hypothesize a direct leptospiral cytotoxic effect on endothelial and on liver-cell membranes. At first, leptospires themselves would induce subcellular changes acting mainly on membrane permeability. Afterwards, their granular forms, including GLP, would act as adjuvant factors. These findings demonstrate that the disarray of liver cell plates at the late phase of the disease is genuine.

Detection of leptospiral antigen (L. interrogans serovar copenhageni serogroup Icterohaemorrhagiae) by immunoelectron microscopy in the liver and kidney of experimentally infected guinea-pigs

Guinea-pigs were experimentally infected with L. interrogans serovar copenhageni serogroup Icterohaemorrhagiae and their liver and kidney were studied by immunoelectron microscopy using the post embedding indirect immunogold labelling technique. Primary antibody was a purified rabbit anti-serum produced against the same leptospiral strain used in the inoculum. Gold-labelled leptospiral antigen (LAg) was found close to cell membranes of hepatocytes, kidney tubular cells and endothelial cells of the interstitial capillaries of the kidney. Afterwards it was internalized by hepatic and tubular cells, and eventually found in lysosomes. Phagolysosomes of Kupffer cells were also found to contain remnants of degraded leptospires and gold-labelled LAg. Gold-labelled intact leptospires were detected at the enlarged intercellular spaces between hepatocytes at the areas of hepatic cell plate disarray, showing the potential for leptospiral migration during the septicaemic phase of the disease potentially contributing to the pathogenesis of the lesions. The affinity of leptospiral antigenic material for cell membranes suggests an initial interaction with cell surface proteins followed by its internalization and cell damage. The nature of antigenic material detected, however, remains undefined; it may be a toxin, an enzyme or any other factor/s involved in leptospiral virulence.

Human fatal yellow fever. Immunohistochemical detection of viral antigens in the liver, kidney and heart

An immunohistochemical method to detect yellow fever antigen was developed using immune sera from rabbits and hamsters and hyperimmune ascitic fluid from mice. A search for the antigen was carried out in liver, kidney and heart in three fatal cases of yellow fever. In the liver it was present in the cytoplasm of hepatocytes, Councilman bodies and Kupffer cells. Yellow fever antigen was also detected in renal tubular epithelium and in groups of myocardial fibers. These findings suggest that viral replication occurs at sites other than the liver. Since yellow fever shares many features with other haemorrhagic fevers the use of immunohistochemistry can impart a significant improvement in the accuracy of its histopathological diagnosis.

[The importance of fixation in immunohistochemistry: distribution of vimentin and cytokeratins in samples fixed in alcohol and formol]

The fixation in ethanol or formalin for trypsin digestion in immunohistochemical detection of cytokeratins and vimentin was assessed in a case of ovarian cystadenofibrocarcinoma. Superior reactivity for both markers was achieved in ethanol-fixed sections, even in samples stocked up to 60 days. Cytokeratin reaction in formalin-fixed sections was better when trypsin was used. However, this digestion was deleterious to vimentin detection. These data are presented to alert surgeons and oncologists on the relevance of fixation of specimens suspicious for neoplasia, since different epitopes may require different fixatives and the inadequate choice in the operative room may impart difficulties when immunohistochemistry is necessary.

Restaging of colorectal cancer based on the identification of lymph node micrometastases through immunoperoxidase staining of CEA and cytokeratins

The present study was performed to identify tumor cells in lymph nodes from colorectal adenocarcinomas considered free of disease by the classic hematoxylin-eosin stain, based on the detection of the carcinoembryonic antigen (CEA) and cytokeratins in neoplastic epithelial cells. For this purpose, 603 lymph nodes from 46 lesions were stained by the peroxidase-antiperoxidase technique. Tumor cells were detected in 22 nodes from 12 patients, mainly in the subcapsular sinuses, permitting a restaging of these patients into two groups: those now considered to have metastatic disease and those free of metastases. However, the 5-year follow-up showed no statistical differences in survival between the two groups.

[Giant solitary gastrinoma of the pancreas]

The authors reported a case of giant solitary pancreatic gastrinoma. A 29-year-old woman complaining of upper abdominal pain and loss of weight of 6 months duration. Four months later she noticed moving abdominal tumor. At the surgery a tumor was identified on pancreatic body measuring 20 centimeters of dimension and it was completely removed. A partial pancreatectomy with pancreatic tail preservation was performed in addition to this the Wirsung duct was joined on pancreatic head. No abdominal metastasis was found. The gastrointestinal transit was re-established by end-to-side Roux-en-Y jejunum-pancreatic anastomosis. The final diagnosis was confirmed by immunohistochemical test (immunoperoxidase). The follow-up was made until 40th postoperative month and after surgery the plasma level of gastrin was 120 pg/ml but at present day is normal. The authors concluded that it was a benign giant solitary pancreatic gastrinoma.

[Program of quality control in gynecologic cytology at the Adolfo Lutz Institute: strategies and critical analysis of results of its pilot implementation]

The Quality Control in the Gynecological Cytology Program, Instituto Adolfo Lutz, was designed to assure a high-standard of laboratory analysis for the Gynecological Cancer Detection and Prevention System in the São Paulo State Public Health Service. This study presents strategies for intra-laboratorial quality control as well as preliminary results on 32,018 cases. The methods applied for the selection of cases to be reviewed were based on clinical and cytological conditions that could mean higher risk of development of neoplasia and/or conditions that might induce difficulties of interpretation. The classification and analysis of the discrepancies found in this initial experience are the highlight points of this Program. Out of the 492 cases submitted to review, 45 had received underscored initial interpretation, although none of them fit international criteria for "false-negative". Overscores were found in 51 cases, with only three cases fitting the criteria for "false-positive". Based on this initial experience, the Quality Control Program will be applied to the other laboratories of the Public Health Service. This intra-laboratory model of control will be coupled with external supervision by Instituto Adolfo Lutz.

Leptospiral antigens (L. interrogans serogroup ictero-haemorrhagiae) in the kidney of experimentally infected guinea pigs and their relation to the pathogenesis of the renal injury

The search for leptospiral antigens (L. interrogans serogroup icterohaemorrhagiae) was carried out in 24 guinea pigs experimentally inoculated with 1 ml of culture containing 10(7)-10(8) leprospires and sequentially sacrificed from the first until the 6th day of infection. Semiquantitative analysis of histopathological variables comprising kidney interstitium, tubules and glomeruli was done in 1 micron sections of tissue embedded in glycolmetacrylate. Leptospiral antigen (LAg) and its glycolipoprotein (GLP) expression were detected through PAP in paraffin embedded tissue. The mild interstitial involvement of the kidney, manifested chiefly by oedema and focal interstitial nephritis seen at the 4th day, progressed to tubular damage at the 6th day, characterized by either swelling or cytoplasmic acidophilia of epithelial cells with loss of cell cohesion and sloughing of cells into the tubular lumina. Brush border alterations and mitochondrial changes were observed. Endothelial cell injury was noted in the interstitial vessels. LAg expression was parallel to the kidney changes: small deposits of elongated forms of LAg were detected at the 4th day either within the vascular lumen or free in the interstitium. A rise in the antigen expression was observed at the 5th day when it was seen either around tubules or in their walls. LAg was detected inside the tubular lumina at the 6th day of infection when granular LAg and GLP were abundant. This sequence reproduces the pathway of leptospires in the kidney and the crescent amounts of antigens detected toward the end of the experiment, with antigen concentration in cases of major tissue damage suggesting a direct action of the microorganisms and/or their products in the pathogesis of the lesions.

Herpes simplex virus in postradiation cervical smears. A morphologic and immunocytochemical study

From January 1987 to August 1988, cytomorphologic criteria of both herpes simplex virus (HSV) and radiation effects were observed in Papanicolaou smears from 3 of 1,340 patients who had received radiotherapy for squamous cell carcinoma of the cervix. Avidin-biotin immunoperoxidase staining, using a rabbit IgG polyclonal HSV antibody, confirmed the presence of HSV antigen in those three postradiation smears. Both multinucleated molded cells and epithelial cells that lacked cytopathic effects were positive for HSV. Three other postradiation smears from these cases were similarly positive for HSV antigen; the one preradiation smear was negative. In situ hybridization and immunoperoxidase studies on sections from the preradiation biopsies were negative: severely altered neoplastic cells showed no reactivity. The absence of HSV markers in the preradiation specimens suggests that the HSV infections were secondary to the radiotherapy; further studies are needed to prove this association and to assess the possible mechanisms. These cases clearly indicate that the overlapping features of radiation and viral effects (such as multinucleation) may be present simultaneously.

Urticarial vasculitis

Thirty seven patients with chronic urticaria were prospectively studied from August 1984 to July 1986. These patients were submitted to regular and immunological laboratory tests. Biopsies were taken from recent urticarial lesions for histologic analysis and also to direct immunofluorescence and immunohistochemistry studies. Vasculitis was found in 27% of the patients. Most of them showed only urticarial lesions except two (20%), that presented residual macula; angioedema occurred in 20% of the urticarial vasculitis (UV) patients; most cases had no systemic manifestations. Serum immunoglobulins and circulant immunocomplexes were increased in both groups. Complement reduction was considered an evidence of vascular aggression, being found in 55% of the UV patients. Direct immunofluorescence studies showed only 10% of positive IgM fluorescence in the vessel walls in the UV group. Immunohistochemical evaluation in the same group revealed mainly slight deposition of immunoglobulins IgG, IgM and IgA in the plasma cells of 80% of the samples and in only 10% there was immunoglobulin deposition in the vessel walls. The authors concluded that conventional histopathology is the best diagnosis method for urticarial vasculitis, direct immunofluorescence and immunoperoxidase being ancillary tools. Therefore, a special group of patients was detected, clinically and therapeutically resembling common urticaria patients, but presenting vasculitis in the histologic exam. This fact leads to the hypothesis that there is a range between common urticaria and urticarial vasculitis with systemic involvement.

[Retrospective analysis of the incidence of midline supratentorial neoplasms in children and young patients: craniopharyngiomas, hypophyseal and pineal neoplasms]

The authors analyzed, in a retrospective study made at the Pathology Department of the Medical School of the University of São Paulo, 1632 cases of intracranial neoplasms in a period of 50 years (1931-1981). The investigation concentrated on 592 cases (36.2%) of patients with age ranging from 0 to 20 years. The overall number of craniopharyngiomas in this group was 21 (3.5%); 8 cases (1.35%) of hypophyseal neoplasms, and 4 cases (6%) of pineal neoplasms. Neoplastic infiltration of the hypophysis and pineal was present in 24 cases (4.0%). No metastases were observed. The description and importance of these findings, and their correlation with data from other authors are presented.

[High resolution light microscopy: adaptation of the method and its use in the study of experimental leptospirosis in guinea pigs]

Morphological lesions in parenchimal and mesenchimal structures of liver and kidney were studied in guinea-pigs experimentally infected with Leptospira interrogans serogroup icterohaemorrhagiae in comparison with a group of non-infected guinea-pigs. All specimens were submitted to conventional light microscopy as well as to high resolution light microscopy, in one micrometer sections of tissue embedded in glycolmethacrylate. High resolution light microscopy, applied for the first time in leptospirosis, was proved very useful, since it enabled us to visualize cellular structures in the same slide used for panoramic view. Cell cohesion, brush borders, pynocytotic vesicles and organellae distributions were parameters especially suitable for analysis at this low-cost, highly precise procedure in microscopy.