Phase II trial of topotecan for the treatment of mesothelioma

The North Central Cancer Treatment Group designed a phase II trial to assess the efficacy and toxicity of topotecan in patients with unresectable malignant pleural mesothelioma. Twenty-two previously untreated patients with unresectable pleural mesothelioma and good performance status (Eastern Cooperative Oncology Group performance status 0, 1, or 2) were enrolled on this trial from October 1993 through July 1994. Nineteen men and three women, median age 66 years (range, 44-78 years), were treated with topotecan 1.5 mg/m2 intravenously over 30 minutes daily for 5 days at 3-week intervals until toxicity, progression of disease, or a patient decided to discontinue treatment. There were seven patients with measurable disease and 15 with evaluable disease; all were assessable for response and toxicity. A total of 113 cycles of treatment were given, for a median of three cycles (range, 1-26 cycles). Myelosuppression was the most frequent toxicity. Eighteen of 21 patients (86%) experienced grade 3 or 4 neutropenia during the initial treatment cycle. The median neutrophil nadir was 0.5 x 10(3)/microl (range, 0.1-1.6 x 10(3)/microl), and the median platelet nadir was 127 x 10(3)/microl (range, 18-460 x 10(3)/microl). Other toxicities more than grade 2 included malaise (two patients), and anorexia, infection, fever, pulmonary, and cardiac in one patient each. There were no objective responses, and 18 patients had stable disease for a median of 74 days. The median survival for all patients was 230 days, with 23% alive at 1 year. Topotecan as administered in this trial is reasonably well tolerated; however, the response rate was insufficient to warrant additional study in pleural mesothelioma.

Immunoreactivity for LN2 and LN3 distinguishes small cell carcinomas from non-small cell carcinomas in the lung

Immunoreactivity to LN2 and LN3, monoclonal antibodies that recognize components of the class II major histocompatibility complex, was assessed in 72 cases of non-small cell lung carcinoma (NSCLC) (32 biopsy specimens, 40 resection specimens) and 64 cases of small cell carcinoma (56 biopsy specimens, 8 resections) of the lung. All cases were reviewed independently by three pathologists for histological classification. Only 1 of the 64 small cell carcinomas showed immunoreactivity for LN2, and none of the 64 cases showed reactivity for LN3. Among the non-small cell carcinomas, 25 of 48 cases were positive for LN2 and 43 of 71 were positive for LN3; the sensitivity was greater for adenocarcinoma (78.5%) than for squamous cell carcinoma (37%). A combined sensitivity of 64.7% was observed when the results of LN2 and LN3 were combined, and this sensitivity was not significantly diminished in the biopsy subset of cases (59.4%). Differentiation within histological subtypes of NSCLC (ie, well, moderate, or poorly differentiated) did not alter test sensitivity. In conclusion, LN2 and LN3, used alone or in combination, appear highly specific for non-small cell carcinoma and moderately sensitive in both biopsy and resection specimens; therefore, these antibodies may be diagnostically useful in distinguishing small cell from non-small cell carcinoma of the lung.

Systematic evaluation of distribution of transgene expression after adenovirus-mediated gene transfer to the transplanted heart

In the transplantation setting, the study and potential treatment of acute and chronic rejection by means of gene therapy will require widespread transgene expression in the donor organ. The distribution of transgene expression after adenovirus-mediated gene transfer via the coronary vasculature in a model of abdominal heterotopic heart transplantation in syngeneic rats (n = 6) was evaluated at 1 week. Reporter gene expression was evenly distributed in the base, the midventricle, and the apex of the transplanted hearts. This study demonstrates that intracoronary administration of the adenoviral vector to the donor heart results in widespread transgene expression.

Distribution of endothelin-1 in transplanted human lungs

BACKGROUND

This study was designed to assess which cells in transplanted lungs express endothelin-1 (ET-1) and if expression of the peptide can be used to discriminate between rejection and infection in transplanted lungs.

METHODS

Transbronchial biopsies (n=104) from 29 human lung transplant recipients were stained immunohistochemically for ET-1. Cells expressing ET-1 (pneumocytes, endothelial cells, airway epithelial cells, lymphocytes, and macrophages) were quantified and correlated with clinical histopathology findings.

RESULTS

ET-1 was expressed in airway epithelial cells (93% of the biopsies), infiltrating macrophages (86%), and lymphocytes (19%) but not in endothelial cells or pneumocytes. ET-1 expression did not vary with rejection, obliterative bronchiolitis, or infection. ET-1 expression did not correlate with age, grade of rejection, pulmonary function, or time after transplantation.

CONCLUSION

In transplanted human lungs, ET-1 is expressed in airway epithelial cells and infiltrating macrophages, and expression does not vary with pathological processes. Therefore, immunostaining for ET-1 probably cannot be used to discriminate between rejection and infection in transplanted lungs.

Alterations in mRNA for inducible and endothelial nitric oxide synthase and plasma nitric oxide with rejection and/or infection of allotransplanted lungs

BACKGROUND

Experiments were designed to determine expression of type II (iNOS) and type III (ecNOS) nitric oxide synthase in lung parenchyma and systemic endothelial cells with rejection and/or infection of single lung allografts.

METHODS

After single lung allotransplantation, dogs were maintained on standard triple immunosuppressive therapy for 5 days and then placed into one of three groups. Group I (n=4) was maintained on immunosuppressants, group II (n=7) immunosuppression was withdrawn to allow acute rejection of the allograft, and group III (n=6) infection was induced by bronchoscopic inoculation of Escherichia coli.

RESULTS

At postoperative days 7-9, no histological evidence of rejection or infection was observed in transplanted lungs of group I. In lungs of group II, rejection ranged from mild to severe; in lungs of group III, infection was severe. Some animals had both rejection and infection (n=8) and were studied separately. Plasma levels of nitric oxide increased comparably with rejection and/or infection compared to preoperative values. Expression of mRNA for ecNOS decreased significantly in lung parenchyma but not in aortic endothelial cells from dogs of groups II and III. However, expression of mRNA for iNOS increased with both rejection and/or infection in both lung parenchyma and aortic endothelial cells.

CONCLUSIONS

iNOS is induced locally within the graft and systemically in aortic endothelial cells with rejection and/or infection of lung allografts. Plasma levels of nitric oxide are elevated with both rejection and infection and may not be useful in the differential diagnosis of these processes after lung transplantation.

Transbronchial gene transfer of endothelial nitric oxide synthase to transplanted lungs

BACKGROUND

Experiments were designed to study the efficiency, distribution, and toxicity of transbronchial adenoviral-mediated transfer of endothelial constitutive nitric oxide synthase (ecNOS) gene to transplanted lungs.

METHODS

Syngeneic orthotopic single-lung transplantation in the rat was performed after airway administration (300 microL, 1 x 10(9) pfu/mL) of either the ecNOS gene or the marker gene beta-Gal (control group) to donor lungs (n=4 each). After 4 days, transgene expression, inflammation, and the presence of apoptosis in the transplanted lungs were assessed by molecular, immunohistochemical, and histologic techniques.

RESULTS

Gene transfer was confirmed by a positive polymerase chain reaction signal for the recombinant ecNOS gene, and recombinant messenger RNA by reverse transcription polymerase chain reaction. Positive immunohistochemical staining for ecNOS was present in more than 75% of pneumocytes only in ecNOS transduced lungs. Calcium-dependent nitric oxide synthase activity was increased in ecNOS- compared with betaGal-transduced lungs (2,139+/-756 versus 47+/-28 pmol x mg protein(-1) x h(-1); p < 0.05). Minimal to mild inflammation was observed in all transplanted lungs; fewer than 0.5% of cells in both groups were apoptotic.

CONCLUSIONS

Transbronchial transfer of ecNOS gene to the transplanted lung results in transduction of pneumocytes with expression of a functionally active transgene product.

Allelic deletion analysis of the FHIT gene predicts poor survival in non-small cell lung cancer

The fragile histidine triad (FHIT) gene at chromosome 3p14.2 is a candidate tumor suppressor gene linked to cancers of the lung, breast, colon, pancreas, and head and neck. Reports of frequent allelic deletion and abnormal transcripts in primary lung tumors plus recent evidence that it is targeted by tobacco smoke carcinogens suggest that it plays an important role in lung carcinogenesis. Non-small cell lung carcinoma still maintains a poor 5-year survival rate with the stage of disease at presentation as a major determinant of prognosis. We examined for allelic deletion at the FHIT locus in a series of 106 non-small cell lung carcinomas for which a full clinical, epidemiological, and 5-year survival profile was available. We found an allelic deletion frequency of 38% at one or two intragenic microsatellites. Allelic deletion of FHIT was related to tumor histology with 4 of 20 adenocarcinomas (20%) displaying loss of heterozygosity (LOH) compared with 12 of 22 (55%) nonadenocarcinomas (P = 0.03). We found that 63% of tumors with LOH of FHIT also had p53 missense mutations whereas only 26% with LOH had wild type p53 negative sequence (P = 0.02). We also found a significant trend toward poorer survival in patients with LOH of at least one locus of the FHIT gene (log rank, P = 0.01). This survival correlation is independent of tumor stage, size, histological subtype, degree of differentiation, and p53 mutation status. Our data support the hypothesis that the loss of the FHIT contributes to the molecular pathogenesis of human lung cancer and is an indicator of poor prognosis.

p21waf1/cip1 and transforming growth factor beta 1 protein expression correlate with survival in non-small cell lung cancer

p21waf1/cip1 encodes a cyclin-dependent kinase inhibitor that is transcriptionally activated by the p53 tumor suppressor gene, transforming growth factor beta 1 (TGF-beta 1), AP2, and other pathways. Because p21waf1/cip1, p53, and TGF-beta 1 all regulate apoptosis and the cell cycle, we tested the hypothesis that their relative protein levels would correlate with biological features including the survival of non-small cell lung cancer (NSCLC) patients. We conducted an immunohistochemical analysis of p21waf1/cip1 and TGF-beta 1 and identified four patient groups with distinct survival outcomes. Concordant p21waf1/cip1 and TGF-beta 1 expression (i.e., either high p21waf1/cip1 and high TGF-beta 1 expression or low p21waf1/cip1 and low TGF-beta 1 expression) predicted 70% disease-free survival at 2000 days of follow-up. Discordant p21waf1/cip1 and TGF-beta 1 expression (i.e., either high p21waf1/cip1 and low TGF-beta 1 expression or low p21waf1/cip1 and high TGF-beta 1 expression) predicted 35% disease-free survival (P = 0.0003; log-rank test). These survival relationships were not attributable to differences in grade, stage, or p53 status. Although current models do not fully explain these complex interactions, most of these data fit a paradigm whereby TGF-beta 1 regulation determines NSCLC survival. In addition to the survival correlation, we found that high p21waf1/cip1 protein expression correlated with high tumor grade (P = 0.014). There is little evidence that p21waf1/cip1 protein levels accurately predict p53 mutation status in NSCLC; specifically, 20 of 48 (42%) tumors with p53 mutations contained high levels of p21waf1/cip1 protein. These findings indicate that p21waf1/cip1 immunohistochemical analysis may provide useful information concerning the biological properties of NSCLC.

Evaluation of biopsy classification for rejection: relation to detection of myocardial damage by monoclonal antimyosin antibody imaging

OBJECTIVES

This study sought to compare the histologic grades of rejection in endomyocardial biopsy specimens with the global estimate of myocardial transplant-related cardiac damage detected by myocardial uptake of monoclonal antimyosin antibodies.

BACKGROUND

The diagnosis and treatment of acute cardiac allograft rejection is based on the interpretation of endomyocardial biopsies. Because allograft rejection is a multifocal process and biopsy is obtained from a small area of the right ventricle, sampling error may occur. Global assessment of myocardial damage associated with graft rejection is now possible with the use of antimyosin scintigraphy. The present study was undertaken to compare the histologic grades of rejection in endomyocardial biopsy specimens with the global assessment of transplant-related myocardial damage detected by antimyosin scintigraphy.

METHODS

Biopsies (n=395) from 112 patients were independently interpreted by three pathologists in a blinded manner according to the original Stanford four-grade (normal, mild, moderate and severe) and the current International Society of Heart and Lung Transplantation (ISHLT) seven-grade (0, 1A, 1B, 2, 3A, 3B and 4) classifications. The results were correlated with 395 antimyosin studies performed at the time of the biopsies. The heart/lung ratio of antimyosin antibody uptake was used to assess the severity of myocardial damage.

RESULTS

In the Stanford biopsy grade classification, significantly higher antimyosin uptake, indicating increasing degrees of myocardial damage, were associated with normal (1.78+/-0.26), mild (1.88+/-0.31) and moderate (1.95+/-0.38) biopsy classifications for rejection (p < 0.01). In the ISHLT classification, significant differences were detected only for antimyosin uptake associated with grades 0 (1.77+/-0.26) and 3A (1.98+/-0.39) but not for intermediate scores (1A, 1B and 2). In view of the similar intensity of antibody uptake among the various grades, ISHLT biopsy scores were regrouped: normal biopsies in grade A; 1A and 1B as grade B; and 2 and 3A as grade C. Antimyosin uptake in grades A, B and C was 1.78+/-0.26, 1.88+/-0.31, 1.95+/-0.38, respectively (p < 0.01).

CONCLUSIONS

The current ISHLT seven-grade scoring system does not reflect the progressive severity of myocardial damage associated with heart transplant rejection. Because myocardial damage constitutes the basis of treatment for allograft rejection, there is a need to reevaluate the ISHLT grading system, given its importance for multicenter trials.

Influence of temperature on adenovirus-mediated gene transfer

OBJECTIVE

The transfer of recombinant genes to donor organs may allow for novel therapeutic approaches to the challenges of acute and chronic rejection. Adenoviral vectors are capable of efficient gene transfer, but use of these vectors during donor organ preservation may be less efficient due to the low temperature. This study was designed to examine the effect of temperature on the efficiency of adenovirus-mediated gene transfer.

METHODS

Gene transfer to human endothelial cells, porcine vascular smooth muscle cells and cultured rat thoracic aortas was examined. Incubation with an adenoviral vector encoding for E. coli beta-galactosidase was performed for 1 h at three different temperatures: 4 degrees C, 10 degrees C and 37 degrees C. Transgene expression was assessed by histochemical staining for beta-galactosidase in transduced cells and by evaluation of beta-galactosidase activity in organ cultures.

RESULTS

Both in human endothelial cells and vascular smooth muscle cells the percentage of positively staining cells following transduction at 37 degrees C was significantly greater than at 4 degrees C and at 10 degrees C (30.55 +/- 7.26% vs. 14.29 +/- 3.79% and 12.43 +/- 2.47%, respectively for endothelial cells, P < 0.01 vs. 4 degrees C and 10 degrees C; and 28.25 +/- 4.52% vs. 17.91 +/- 3.76% and 16.63 +/- 3.92%, respectively for smooth muscle cells, P < 0.05 vs. 4 degrees C, P < 0.01 vs. 10 degrees C). Beta-galactosidase activity was significantly greater in aortas transduced at 37 degrees C than in vessels transduced at 4 degrees C and 10 degrees C (289,700 +/- 113,300 vs. 149,600 +/- 54,390 and 108,800 +/- 23,140 relative chemiluminesce units/mg of total protein, respectively; P < 0.05 vs. 4 degrees C, P < 0.001 vs. 10 degrees C).

CONCLUSIONS

The present study demonstrates that the efficiency of adenovirus-mediated gene transfer is significantly reduced at lower temperatures. The need for cold preservation of donor organs may render efficient adenovirus-mediated gene transfer more difficult in the transplantation setting.

Pulmonary mycotoxicosis: a clinicopathologic study of three cases

Pulmonary mycotoxicosis (PM), also termed organic dust toxic syndrome or silo unloader's syndrome, is an acute illness resulting from massive inhalation of microbial toxins in organic dusts. It has not been well described histologically. Three cases of PM are presented in this report. Open lung biopsies were examined in each case. All of the patients were farmers with no prior lung disease. One had burning in his eyes, throat, and chest after exposure to moldy silage; chills, fever, dry cough, malaise, and weakness developed within 24 hours. Two patients presented with fever, progressive dyspnea, cough, and fatigue within 24 hours of emptying a corncrib, cleaning a chicken coop, and baling hay. Bilateral alveolar and interstitial infiltrates on chest roentgenograms and leukocytosis with neutrophilia were observed in all of the three patients. Two patients became hypoxemic and required mechanical ventilation. Histologic examination showed acute and organizing diffuse alveolar damage in two biopsy specimens and an acute bronchopneumonia in the third. One specimen had 1- to 10-microm ovoid organisms demonstrable with methenamine silver stains; cultures grew Fusarium and Penicillium species. The other two biopsy specimens had negative tissue cultures and special stains for organisms, although Penicillium species were grown from a preoperative bronchoalveolar lavage in one case. The two patients on mechanical ventilation recovered completely with high-dose steroids. The third patient recovered without steroids. No patient had residual functional deficits or chest radiographic abnormalities. PM can be distinguished from allergic and infectious diseases common in individuals exposed to large amounts of organic dust by its clinicopathologic features.

Gene therapy in lung transplantation: effective gene transfer via the airways

OBJECTIVES

Gene therapy may provide a means of modifying factors that contribute to the development of pathologic processes in transplanted lungs. Experiments were designed to study the feasibility of adenovirus-mediated gene transfer by way of the airways to the transplanted lung.

METHODS

Orthotopic left lung transplantation (Lewis to Lewis rats) was performed on four groups of animals. 300 microl of adenovirus solution encoding for beta-galactosidase was infused into the left bronchus of donor rats at viral concentrations of 10(8) pfu/ml (n = 5), 10(9) pfu/ml (n = 6), and 10(10) pfu/ml (n = 6), and the lung was ventilated for 5 minutes. Controls (n = 6) received medium only. Seven days after transplantation, native and transduced, transplanted lungs were harvested. Sections of lung were fixed and stained with a solution of X-Gal (5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside) and staining was evaluated for distribution by cell type and intensity.

RESULTS

Beta-galactosidase expression was absent in the control group and in the native lungs. Two of five lungs in the 10(8) group expressed beta-galactosidase, but in a limited distribution and intensity. All six lungs in the 10(9) group and five of six lungs in the 10(10) group expressed beta-galactosidase. The distribution and intensity of beta-galactosidase expression ranged from only a few cells staining per slide to up to 75%. Pneumocytes were the most frequently stained cell type followed by alveolar macrophages.

CONCLUSIONS

Gene transfer to the transplanted lung via the bronchial route is feasible and offers a novel technique to modify pathologic processes in the transplanted lung.

Prognostic significance of histopathologic subsets in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a generally fatal disorder with a reported median survival of 3 to 6 yr. This has been based on relatively few studies with diagnoses inconsistently confirmed by adequate lung biopsy. Retrospective analysis of 104 patients with IPF who had open lung biopsy (OLB) at Mayo Medical Center from 1976 to 1985 was performed to establish the overall survival rate, the spectrum of histopathological subgroups and their associated prognostic significance. The study group consisted of 54 men and 50 women with a median age of 63 yr. Median survival was 3.8 yr after diagnosis by OLB with an estimated 10 yr survival of 27%. Current histopathologic review showed a heterogeneous group including usual interstitial pneumonia (UIP), desquamative interstitial pneumonia (DIP), nonspecific interstitial pneumonia/fibrosis (NSIP), acute interstitial pneumonia (AIP), bronchiolitis, bronchiolitis obliterans organizing pneumonia (BOOP), and others. Median survival of the UIP group was 2.8 yr which is significantly worse (p < 0.001) than for other subgroups of chronic interstitial pneumonias. IPF includes several histopathologic subgroups with significantly different survival rates. Patients with UIP have worse survival than patients with other types of idiopathic chronic interstitial pneumonias including NSIP. Accurate histopathologic classification is essential for prognostication in patients with IPF.

Immunosuppression prolongs adenoviral mediated transgene expression in cardiac allograft transplantation

BACKGROUND

The immune response to adenoviral vectors used in gene transfer limits the duration of transgene expression and thus poses a potential limitation to their effectiveness for gene therapy. The need for immunosuppression in transplantation may modify this immune response and facilitate prolonged transgene expression. This study hypothesizes that in the setting of heart transplantation, the use of routine immunosuppression will prolong adenoviral-mediated transgene expression.

METHODS AND RESULTS

In a model of rat heterotopic abdominal heart transplantation, 350 microliters of viral solution (1 x 10(9) pfu/ml) was infused into the coronary arteries of donor hearts at the time of procurement. The duration of transgene expression was examined following (a) syngeneic transplantation in non-immunosuppressed animals (group A): (b) syngeneic transplantation in immunosuppressed animals (group B); and (c) allogeneic transplantation in immunosuppressed animals (group C). After transplantation donor hearts were studied at; 1, 4, 8 and 12 weeks. Transgene expression was assessed by histochemical staining of tissue cross sections for beta-galactosidase activity. In the non-immunosuppressed syngeneic group (group A), transgene expression had largely disappeared by 4 weeks, whereas in both the immunosuppressed syngeneic (group B) and immunosuppressed allogeneic (group C) animals expression of the reporter gene persisted for the 12 weeks of the study, although the level of expression decreased significantly over time.

CONCLUSIONS

This study demonstrates that transgene expression using adenoviral vectors is prolonged by immunosuppression in the heart transplantation setting.

Characteristics of endothelin receptors in acutely rejecting transplanted lungs

Experiments were designed to characterize endothelin receptors in bronchi and parenchyma of transplanted lungs during acute rejection. Third-order bronchi from autografted or allografted lungs were either cut into rings and suspended in organ chambers for the measurement of isometric force or frozen for isolation of membrane proteins. Lung parenchyma was prepared for histology or isolation of membrane protein. The grade of rejection was 2.74+/-0.17 (n= 19) in allotransplanted lungs; evidence of infection was present in 58% of the transplanted lungs. In organ chamber experiments, endothelin 1 (which stimulates endothelin A receptors) caused comparable contraction of bronchi from autotransplanted and allotransplanted rejecting lungs. Endothelin 3 (which stimulates endothelin A and B receptors) caused contractions of bronchi from autotransplanted lungs which were not different from those caused by endothelin 1. In contrast, contractions caused by endothelin 3 were reduced in bronchi from rejecting allotransplanted lungs. The magnitude of contractions caused by endothelin 3 was reduced further when infection was present with rejection. Competitive inhibition of 125I-endothelin 1 by endothelin 3 was significant for a two-site binding model in membranes prepared from all bronchi and lung parenchyma. The total number of binding sites (Bmax) was reduced significantly in bronchi and parenchyma from rejecting lungs with or without infection. The relative proportions of high-affinity and low-affinity binding sites did not change. Affinities of both high- and low-affinity receptors were not altered with rejection. These results indicate that at least two subtypes of endothelin receptors are present on canine bronchial smooth muscle and parenchyma. The number of endothelin receptors associated with bronchial contractions is reduced with rejection of lung allografts.

Organizing diffuse alveolar damage associated with progressive systemic sclerosis

Diffuse alveolar damage (DAD) is a relatively nonspecific pattern of acute lung injury that can be observed in a wide range of clinical circumstances. DAD has often been recognized in association with various connective tissue diseases; however, to our knowledge, it has not been previously reported in the setting of progressive systemic sclerosis. Herein we describe two patients with established diagnoses of progressive systemic sclerosis who had development of the acute respiratory distress syndrome. Open-lung biopsy specimens from both patients showed a histologic pattern of DAD with no identifiable cause other than their progressive systemic sclerosis. Our results suggest that DAD should be added to the list of pleuropulmonary complications of progressive systemic sclerosis.

Eosinophilic myocarditis manifesting as myocardial infarction: early diagnosis and successful treatment

OBJECTIVE

To report a case of eosinophilic myocarditis with remarkable initial clinical manifestations and outcome.

MATERIAL AND METHODS

A 67-year-old woman with hypertension and a history of asthma and drug hypersensitivity was referred to our institution with a diagnosis of acute myocardial infarction on the basis of severe chest pain, ST elevation on an electrocardiogram, and a slight increase in cardiac enzymes. Further diagnostic studies were performed.

RESULTS

Echocardiography disclosed left ventricular dysfunction in conjunction with apical asynergy, thinning, and thrombus. The eosinophil count in the peripheral blood was increased only slightly. Coronary angiography showed normal arteries and prompted the performance of endomyocardial biopsy, which revealed active eosinophilic myocarditis. After corticosteroid therapy, global and regional left ventricular function returned to normal.

CONCLUSION

This unusual clinical picture and outcome demonstrate that eosinophilic myocarditis may simulate acute myocardial infarction and should be considered in patients with a history of allergies or acute left ventricular dysfunction, even in the absence of pronounced eosinophilia in the peripheral blood. With appropriate medical therapy, recovery for these patients can be complete.

Calcified amorphous tumor of the heart (cardiac CAT)

Eleven cases of poorly characterized nonneoplastic endocardially based intracavitary cardiac masses have been seen at the Mayo Clinic between 1965 and 1994. They occurred in 7 women and 4 men from age 16 to 75 years (mean, 52 years). The patients presented with a wide variety of symptoms and underlying diseases. The lesions were diagnosed as a primary cardiac neoplasm in 6 of 8 patients having echocardiography. Surgical excision was the treatment of choice in 10 patients; the 11th patient died of noncardiac causes 30 days after the mass was discovered. Grossly, the lesions were firm, yellow-white, and partially calcified, and arose in any of the four chambers. Microscopically, all lesions were characterized by nodular calcium in a background of degenerating blood elements and chronic inflammation. All patients had a benign course relative to their cardiac lesion. Repeat echocardiogram in two patients showed residual calcium in the region of the initial tumor. Although these lesions may represent calcified thrombi, the clinical presentation did not suggest thrombosis as the most likely explanation for their occurrence. Based on the combined clinical presentation and microscopic appearance, the authors propose the descriptive name calcified amorphous tumors (cardiac CAT) to describe this group to nonneoplastic cardiac masses.

Effects of mononuclear cells on pulmonary arteries from rejecting transplanted lungs

Experiments were designed to determine responses of pulmonary arteries from an acutely rejecting, transplanted lung to rejection-activated mononuclear cells. Pulmonary arteries and macrophage-depleted mononuclear cells were obtained from unoperated dogs (control) and dogs with rejecting single lung allotransplants (transplanted, rejecting). In some arteries, the endothelium was removed deliberately. Pulmonary arteries were suspended for measurement of isometric force in organ chambers. Contractions to potassium chloride (60 M) were greater in rings of pulmonary arteries from rejecting compared with control dogs. Mononuclear cells from both control and transplanted dogs caused cell number-dependent contractions of autogenous pulmonary arteries. Contractions to cells were decreased when the endothelium was present only in arteries from control dogs; these contractions were increased by the L-arginine analog N(G)-monomethyl-L-arginine (10(-4) M) but not by indomethacin (10(-5) M). Contractions to mononuclear cells were reduced by superoxide dismutase (150 U/ml) and catalase (1,200 U/ml) in arteries without endothelium from control but not transplanted dogs. In arteries from transplanted dogs, contractions to mononuclear cells were reduced by desferoxamine (10(-3) M). Results suggest that interactions between mononuclear cells and pulmonary arteries are modified during rejection of lung allografts so that, during rejection, 1) endothelium-derived nitric oxide no longer antagonizes contractions to substances produced by the mononuclear cells and 2) contractions of smooth muscle from rejecting arteries to mononuclear cells may be mediated by radicals other than superoxide.

Colchicine versus prednisone as treatment of usual interstitial pneumonia

OBJECTIVE

To assess the results with colchicine and prednisone as initial single-drug therapy in patients with usual interstitial pneumonia (UIP).

MATERIAL AND METHODS

We reviewed the serial pulmonary function test results in 22 patients with typical clinical and high-resolution computed tomographic features of UIP who were treated with colchicine as initial single-agent therapy and compared them with a group of 22 historical patients with UIP of similar severity diagnosed by open-lung biopsy who were given prednisone as initial single-drug therapy.

RESULTS

No significant difference was detected in the rate of decline of pulmonary function or in the time to "failure" between the two study groups. A trend was suggested for more rapid decline of pulmonary function in the prednisone-treated than in the colchicine-treated group. The design of this study does not allow distinction between a possible beneficial effect of colchicine and a possible adverse effect related to weaning from high-dose prednisone. Colchicine was well tolerated; few side effects other than mild diarrhea were noted in those patients able to take the drug long enough to return for pulmonary function testing at 3 months. In comparison, the side effects of prednisone were more serious and were not always reversible with cessation of therapy.

CONCLUSION

This study lends further support to the assumption that colchicine may be a satisfactory and less hazardous substitute for prednisone in the treatment of patients with UIP.

Cigarette smoking: CT and pathologic findings of associated pulmonary diseases

The health risks associated with cigarette smoking are well known. Cigarette smoking is the most important causative factor in the development of bronchogenic carcinoma. Pulmonary diseases such as chronic bronchitis, centrilobular and panacinar emphysema, respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), and pulmonary Langerhans cell histiocytosis are also related to cigarette smoking. In adenocarcinoma and squamous cell carcinoma, the most common manifestation at computed tomography (CT) is a solitary pulmonary nodule; in small cell carcinoma, hilar and mediastinal adenopathy secondary to metastases; and in large cell carcinoma, a mass with central necrosis or cavitation in the lung periphery. For chronic bronchitis, the most common CT finding is bronchial wall thickening, but this finding is nonspecific. Emphysema, both centrilobular and panacinar associated with alpha-1-antitrypsin deficiency, usually manifests as areas of decreased attenuation and may involve bullous changes. However, centrilobular emphysema more commonly involves the upper lungs, whereas panacinar emphysema more commonly involves the lower lungs. Most patients with RB-ILD have normal high-resolution CT scans; however, abnormalities may be present, the most common of which are areas of ground-glass attenuation. CT appearance of pulmonary Langerhans cell histiocytosis varies depending on the disease stage: In the early stage, typical CT findings include multiple nodules, usually accompanied by cystic spaces with thin, well-defined walls. As the disease progresses, the cystic spaces become more numerous and the number of nodules decreases.

Acute eosinophilic pneumonia: histopathologic findings in nine patients

Acute eosinophilic pneumonia is characterized by acute respiratory insufficiency, hypoxemia, fever, diffuse radiographic infiltrates, and eosinophilia in bronchoalveolar lavage fluid (BALF) or lung biopsies in the absence of infection, atopy, or asthma. A rapid response to corticosteroids is characteristic. We reviewed our experience with nine cases of acute lung disease with histologic features of acute and organizing diffuse alveolar damage and prominent interstitial and alveolar eosinophils in order to determine whether this pathology was characteristic of acute eosinophilic pneumonia. The mean age of the patients (four men and five women) was 53 yr (range: 33 to 71 yr). They presented with 2 to 21 d of dyspnea, cough, myalgias, and fever. All were hypoxic and had bilateral infiltrates on chest radiographs. Peripheral blood eosinophilia was present in four of eight patients (peripheral blood count unavailable for one patient). All patients were treated with high-dose corticosteroids with a mean time to symptomatic and radiographic improvement of 4 d. Seven of the nine patients enrolled in the study are alive without relapse; one patient has a mild deficit in diffusing capacity, and one patient died of a myocardial infarct while improving on therapy. The presence of eosinophils in cases of acute respiratory insufficiency due to diffuse alveolar damage (DAD) should suggest the diagnostic possibility of acute eosinophilic pneumonia. Acute eosinophilic pneumonia should be distinguished from other causes of DAD because of important differences in natural history.

Endothelin-1 and cell proliferation in lung organ cultures. Implications for lung allografts

Endothelin-1 (ET-1) is found in bronchoalveolar lavage fluid in patients following lung transplantation. ET-1 causes contraction of isolated pulmonary vessels and bronchi and stimulates proliferation of smooth muscle cells in culture. Therefore, ET-1 could contribute to the smooth muscle hyperplasia and stromal proliferation seen in chronic rejection of lung allografts. Experiments were designed to determine whether (1) ET-1 stimulates proliferation of pulmonary tissue, (2) proliferation is increased in rejecting allotransplanted lungs, (3) endothelin-A receptors mediate the proliferative response, and (4) ET-1 is produced by activated infiltrating immunocompetent cells. Lung organ cultures were prepared from unoperated dogs and dogs with rejecting single lung allografts. Incubation of organ cultures from unoperated dogs with ET-1 (10(-9) to 10(-7) M)) increased positive staining for proliferation cell nuclear antigen (PCNA) in lung parenchyma. PCNA staining was not decreased by the endothelin-A antagonist BQ123 (10(-6) M). In addition, immunostaining for endothelin-B receptors was present in sections of unoperated but not rejecting lungs. PCNA staining in lung cultures from rejecting allotransplanted dogs was significantly greater than that from unoperated dogs. Positive immunohistochemical staining for ET-1 was found in mononuclear cells infiltrating rejecting transplanted lungs. In conclusion, exogenous ET-1 is mitogenic in lung organ cultures through receptors other than endothelin-A. Proliferation in rejecting transplanted lungs is increased compared with unoperated lungs. Mononuclear cells may be a source of endothelin-1 in the rejecting lung. ET-1, therefore could, in synergism with other cytokines, contribute to acute and chronic pathological changes seen in pulmonary rejection.

Adenomatoid tumors of the pleura

We report two cases of small pleural nodules showing the distinctive histologic appearance of adenomatoid tumor. Both lesions were discovered incidentally during surgery in patients undergoing lung resection for unrelated intrapulmonary masses: lung carcinoma in one case and histoplasmosis in the other. The tumors were composed of a focal proliferation of epithelioid cells forming vacuoles and tubular spaces in a fibrous stroma, as seen in adenomatoid tumors from other sites. The differential diagnosis in both cases included metastatic signet ring cell carcinoma. The mesothelial nature of the lesions was supported by immunohistochemical and ultrastructural evidence. The tumor cells in both cases were positive for cytokeratin but negative for carcinoembryonic antigen and LeuM1. One case was also negative for BER-EP4, B72.3, CD34, and Factor VIII. Electron microscopy in this case demonstrated well-developed basal laminae, desmosomes, and numerous slender microvilli along the luminal surfaces of the tumor cells. Adenomatoid tumors are regarded as a benign variant of mesothelioma. Despite the abundance of mesothelial cells in the pleura, adenomatoid tumors are apparently extremely rare in this location. Separation from malignant lesions such as adenocarcinoma and epithelioid hemangioendothelioma is important.