Search PubMed⌕ Search

Biomedical subjects

C A Moran

Publications and source records attributed to C A Moran.

At least 73 records · Page 4Linked to original sources
PubMed1997

Yolk sac tumors of the mediastinum with prominent spindle cell features: a clinicopathologic study of three cases.

Three cases of primary mediastinal yolk sac tumors with prominent spindle cell features are presented. The patients were three men 24-34 years of age (mean 29). Clinically, two patients presented with symptoms of chest pain and cough; no clinical information was provided for the third patient. Grossly, the tumors were described as large mediastinal masses, with a hemorrhagic and necrotic cut surface. Histologically, the tumors were characterized by a predominantly atypical spindle cell proliferation admixed with areas that showed focally the characteristic reticular growth pattern of yolk sac tumors, with the presence of Schiller-Duval bodies and intra- and extracellular hyaline globules. Immunohistochemical studies performed in one case showed positive staining for keratin and alpha-fetoprotein in both the spindle cell and reticular components of the tumor. Follow-up information was obtained in two patients; they both died of tumor with metastases to the lungs 1 year after initial diagnosis. The present cases expand the spectrum of histopathologic growth patterns that may be observed in yolk sac tumors of the mediastinum and stress the issue of careful sampling and evaluation of mediastinal neoplasms for arriving at the correct diagnosis.

Adult↗
PubMed1997

Primary melanoma of the lung: a clinicopathologic and immunohistochemical study of eight cases.

Primary malignant melanoma of the lung (PMML) is an uncommon neoplasm that may be confused with more conventional types of lung cancer. Although the previously proposed criteria for diagnosis, including the presence of an in situ component, are often difficult to satisfy, this lesion is characterized by a poor prognosis, ultimately leading to patient death. We report eight cases of PMML that presented as solitary, central endobronchial neoplasms, resulting in a picture that closely resembled carcinoid tumor or poorly differentiated non-small-cell carcinoma of the lung. The mean age at diagnosis was 51 years (range 45-71). The patients included one woman and seven men. The histologic growth pattern varied from organoid to fascicular and included epithelioid to spindled cells with hyperchromatic to vesicular nuclei, prominent eosinophilic nucleoli, and abundant eosinophilic to clear cytoplasm with occasional intranuclear cytoplasmic inclusions. A bronchial in situ component was present in four cases. Initial interpretations included carcinoid tumor, non-small-cell carcinoma, and malignant melanoma. Melanin was present in all neoplasms on hematoxylin and eosin staining, although very focally in one case, and was Fontana-Masson positive in all cases. Immunohistochemically, diffuse strong positivity for S-100, HMB-45, and vimentin was present in all seven tumors tested. All seven tumors were negative for cytokeratin, CAM 5.2, and chromogranin. Ultrastructural examination of the eighth case showed dysmorphic premelanosomes but no neurosecretory granules. None of the patients had disseminated disease at presentation, and all patients underwent surgical resection (seven lobectomies and one excision). In this series, primary malignant melanoma of the lung was characterized by an aggressive postoperative course, with five patients dying of metastatic disease from 4 to 32 months after resection (median 14 months). Two patients are alive with metastatic disease at 4 and 30 months after surgery, and the eighth patient is alive with no evidence of disease 108 months after surgery at last follow-up. Metastatic melanoma was identified in various sites, including the lungs, adrenal glands, liver, mesentery, brain, and bone. The cases herein presented indicate that PMML should be included in the differential diagnosis of primary bronchial tumors.

Aged↗
PubMed1997

Hepatoid yolk sac tumors of the mediastinum: a clinicopathologic and immunohistochemical study of four cases.

Four cases of primary hepatoid yolk sac tumors of the anterior mediastinum are described. The patients were all men between the ages of 26 and 40 years (median 33). Clinically, they all presented with a history of shortness of breath and chest pain of several weeks' duration. None of the patients had a history of germ cell tumor elsewhere or evidence of any hepatic abnormality. Grossly, all the tumors were described as large mediastinal masses that impinged on adjacent structures. Histologically, they were characterized by sheets of medium-sized, round to polygonal neoplastic cells with moderate amounts of eosinophilic cytoplasm and round to oval nuclei with prominent nucleoli. The cellular proliferation was homogeneous and displayed moderate cellular atypia and scattered mitotic activity. All the tumors showed focally the presence of more conventional areas of yolk sac tumor, with islands of tumor cells showing a reticular pattern of growth admixed with scattered intra- and extracellular hyaline globules and occasional Schiller-Duval bodies. Immunohistochemical studies showed strong positivity of the tumor cells for alpha-fetoprotein in both components of the lesions. Follow-up information was available in three patients, all of whom developed lung metastases within a year after initial diagnosis. Two of these patients died of tumor within the same period, whereas a third patient has been lost to follow-up. The present cases illustrate an unusual histologic pattern of yolk sac tumor in the mediastinum and highlight the importance of considering this tumor in the differential diagnosis of lesions showing a hepatoid pattern of growth in the mediastinal area.

Adult↗
PubMed1997

Thymoma with pseudosarcomatous stroma: report of an unusual histologic variant of thymic epithelial neoplasm that may simulate carcinosarcoma.

Six cases are described of an unusual type of primary thymic epithelial neoplasm characterized by a biphasic epithelial/spindle cell morphology that closely resembled a carcinosarcoma. The patients were two women and four men 28-70 years of age. The tumors presented clinically as asymptomatic anterior mediastinal masses found incidentally on routine chest radiographs. All patients were treated by complete surgical excision. Grossly, the tumors consisted of well-circumscribed, encapsulated masses that measured 6-14 cm in greatest diameter and showed a gray-white, homogeneous, rubbery cut surface. Histologically, the lesions were composed of anastomosing islands and cords of oval to polygonal epithelial cells displaying large nuclei with occasional prominent nucleoli and rare mitotic figures, separated by areas containing a highly cellular spindle cell proliferation without nuclear atypia. Thymic remnants could be identified in the periphery of the lesions in four cases. Immunohistochemical stains showed diffuse strong positivity for keratin and focally for epithelial membrane antigen (EMA) in the epithelial cell component, and strong positivity for vimentin and focally for actin in the spindle cell stromal component. Stains for keratin, EMA, desmin, S-100 protein, and CD34 were negative in the spindle stromal cells in all cases except one, in which EMA positivity was present; CD5 stains were negative in the epithelial cells in all cases examined. Electron microscopic examination in one case showed well-formed desmosomes and tonofilaments in the epithelial elements, as well as features indicative of fibroblastic differentiation in the spindle stromal cells. Because of the unusually florid spindle cell stromal component and the focally atypical features of the epithelial cells, some of these tumors initially were misinterpreted as examples of carcinosarcoma. Clinical follow-up in five cases showed that the patients were alive and without evidence of disease over a period of 5-20 years (mean follow-up 10 years), suggesting a benign or very low grade malignant biologic behavior. The present cases appear to represent an unusual, previously undescribed morphologic variant of thymoma characterized by a prominent pseudosarcomatous stromal component. Because of the distinctive histologic appearance and indolent clinical behavior, these lesions should be distinguished from other more aggressive anterior mediastinal neoplasms displaying a biphasic morphology.

Adult↗
PubMed1997

Primary leiomyosarcomas of the lung: a clinicopathologic and immunohistochemical study of 18 cases.

We studied 18 patients with primary malignant smooth muscle tumors of the lung (7 women and 11 men, 5-76 yr old, with a mean age of 50 yr). Lesions varied from 1.7 to 10 cm in greatest diameter. The tumors were classified as low (4 cases), intermediate (2), or high grade (12). Low-grade lesions were characterized by an orderly proliferation of fascicles of spindle cells that intersected at right angles and showed oval-to-spindle cells with cigar-shaped nuclei, minimal pleomorphism, and low mitotic activity, without hemorrhage or necrosis. Intermediate-grade lesions retained the fascicular configuration but showed increased cellularity with atypia and dense chromatin pattern, occasional pleomorphism, and mild increase in mitotic activity. High-grade lesions showed high cellularity, marked pleomorphism and atypia, frequent areas of hemorrhage and necrosis, and high mitotic activity. Immunohistochemical studies in 16 cases showed positive staining of tumor cells with smooth muscle actin in 12, desmin in 5, and coexpression of actin and/or desmin and keratin in 3. Six patients with low- and intermediate-grade lesions were alive and well from 2 to 12 years after diagnosis (mean follow-up time, 6 yr); 8 with high-grade lesions died of their tumors with widespread metastases from 1 to 24 months after diagnosis (median survival time, 5 mo). One patient whose tumor showed features of high-grade leiomyosarcoma was alive and well 12 years after surgery. Three patients with high-grade tumors were lost to follow-up. Our findings suggest that histologic grade may be the most reliable prognostic parameter for predicting clinical behavior in primary leiomyosarcoma of the lung and that smooth muscle actin is the most sensitive immunohistochemical marker for establishing the diagnosis in these tumors. Primary leiomyosarcoma should be considered in the differential diagnosis of pulmonary spindle cell neoplasms; histologic grading may be of value in the planning of therapy and assessment of prognosis for these lesions.

Actins↗
PubMed1997

Pulmonary alveolar microlithiasis. A clinicopathologic and chemical analysis of seven cases.

OBJECTIVE: To determine the clinical features and outcome of patients with pulmonary alveolar microlithiasis and to determine the chemical composition of the microliths. CASE MATERIAL: We studied seven cases of pulmonary alveolar microlithiasis. The patients were six women and one man, aged 19 to 70 years (mean age 44.5 years). Clinically, five patients were known to have suffered from this condition for 5 to 41 years. One patient presented with shortness of breath, and another had a gradual decrease in exercise tolerance. None of the patients had a previous history of disturbances in metabolism or any other relevant medical condition. Reports on radiographic studies were available in six cases, and chest radiographs were available for review in the seventh case. They all showed diffuse bilateral pulmonary infiltrates. Open lung biopsies were performed in two patients, and autopsy lung material was reviewed in five patients. RESULTS: Histologically, the lung showed the typical features of pulmonary alveolar microlithiasis, that is, presence of numerous microliths filling the alveolar spaces with either a normal or thickened fibrotic interstitium. Chemical analysis performed on the lung tissue of six of these patients revealed that the microliths consisted principally of calcium and phosphorus salts. Five of these patients died of respiratory failure; however, their deaths occurred from 5 to 41 years following the initial diagnosis. No follow-up information was obtained in two patients. CONCLUSIONS: The findings of this study confirm that pulmonary alveolar microlithiasis can be seen in any age group and that the microliths are composed principally of salts of calcium and phosphorus. Additionally, these cases confirm that the disease typically follows a protracted course.

Adult↗
PubMed1997

Mediastinal yolk sac tumors associated with prominent multilocular cystic changes of thymic epithelium: a clinicopathologic and immunohistochemical study of five cases.

Five cases of yolk sac tumor of the anterior mediastinum associated with prominent thymic cystic changes are presented. The patients were five men between the ages of 17 and 22 years (mean, 19.5 yr). Clinically, four patients presented with symptoms of chest pain and shortness of breath, whereas the fifth was asymptomatic: his tumor was discovered during a routine physical examination. None of the patients had a history of previous tumor elsewhere. Grossly, the tumors were described as cystic lesions measuring between 8 and 12 cm in greatest dimension. Histologically, the tumors showed prominent cystic changes reminiscent of those observed in acquired multilocular thymic cysts, i.e., the presence of cystic cavities lined by squamous epithelium with prominent inflammatory changes, lymphoid hyperplasia, cholesterol cleft granulomas, and remnants of thymic tissue in the walls of the cysts. In addition, there was a neoplastic cellular proliferation composed of small cells with scant cytoplasm, round nuclei, and inconspicuous nucleoli adopting a reticular pattern of growth and, in some areas, embedded in abundant myxoid stroma. Numerous intra- and extracellular hyaline globules, as well as Schiller-Duval bodies, could also be identified. Immunohistochemical studies showed positive reaction with alpha-fetoprotein antibodies in the tumor cells. Follow-up information obtained in these patients showed that all had died of tumor 1 to 3 years after initial diagnosis. The present cases document another unusual but distinctive growth pattern of yolk sac tumor in the mediastinum and highlight the importance of proper sampling of cystic lesions in this location.

Adolescent↗
PubMed1997

Pulmonary lipomatosis: a variant of placental transmogrification.

An unusual pulmonary lesion is presented. The patient is a 55-year-old white man with a 2-week history of pleuritic chest pain, shortness of breath, and bronchopneumonia. The patient had also a history of smoking and chronic cough for 12 years. Chest radiographic studies showed a 20-cm bulla in the left upper lobe. A left upper lobectomy was performed obtaining an almost completely collapsed lobe with destruction of the normal architecture by a meshwork of yellowish tissue. Histologically, there were strikingly papillary structures composed almost exclusively of mature adipose tissue with small collections of inflammatory cells. Minimal emphysema in the adjacent lung parenchyma was observed. The case herein presented most likely represents part of the spectrum of placental transmogrification or placentoid bullous lesions of the lung.

Adipose Tissue↗
PubMed1996

Primary intrapulmonary meningiomas. A clinicopathologic and immunohistochemical study of ten cases.

BACKGROUND: Primary intrapulmonary meningiomas are rare, and their occurrence has been reported in the literature only sporadically. METHODS: The clinical, pathologic, and immunohistochemical features of ten cases of primary intrapulmonary meningioma were reviewed. RESULTS: The patients were 4 women and 6 men between the ages of 30 and 72 years (mean age: 51 years). In nine patients, the lung tumor was found during a routine chest radiographic study. The only patient with clinical symptomatology was a man who presented with a persistent cough of 45 days' duration. None of the patients had a previous history of central nervous system (CNS) meningioma or other tumor at the time of diagnosis. Macroscopically, the neoplasms were described as soft, white, well circumscribed lesions that ranged in size from 1.5 cm to 4 cm in greatest dimension. No predilection for any particular lobe or segment of lung was observed. Histologically, all the tumors showed the characteristic growth pattern of CNS meningiomas and were classified accordingly. Seven tumors were transitional meningiomas, and three were fibrous meningiomas. Psammoma bodies were observed in 50% of the tumors. Immunohistochemically, six cases showed positive staining for Epithelial Membrane Antigen (EMA) and vimentin, whereas two of these cases also showed focal positive staining for CD34. Clinical follow-up ranging from 1 month to 24 years was obtained for 6 patients. All the patients were alive and well except for 1 female who died 20 years after the initial diagnosis at age 92 of a cerebrovascular accident. CONCLUSIONS: The clinical follow-up in this study suggests that these tumors are amenable to surgical resection, and when the tumor is resected in its entirety, the patient is cured. In addition, the immunohistochemical results suggest that, as in CNS meningiomas, EMA and vimentin are the most reliable immunologic markers for these tumors.

Adult↗
PubMed1996

Primary mediastinal and testicular seminomas: a comparison of K-ras-2 gene sequence and p53 immunoperoxidase analysis of 26 cases.

Primary mediastinal seminomas (MS) are rare tumors. Histologically, they are similar to their counterpart in the gonads. The survival rate has varied from 50% to 85% in different series. However, large series of these tumors primarily in the mediastinum are lacking. At the molecular level, a few reports document K-ras mutations in up to 40% of testicular seminomas (TS), localized predominantly to codon 12. Reports on TS p53 immunohistochemistry (IHC) range from negative to overexpression approaching 90% of cases, and by sequence analysis one small series showed a 23% mutation rate. To date, no analyses have been performed for either K-ras mutations or p53 immunohistochemical expression in primary MS. The authors studied 13 cases each of primary MS and TS from archival formalin-fixed, paraffin-embedded sections in which adequate tumor sampling and clinical history, including serological studies, and histological, histochemical, and IHC staining, were performed to confirm the diagnosis. p53 immunoperoxidase staining using citrate buffer/microwave antigen retrieval was performed. Topographic genotyping was performed on 5-microns-thick tissue sections up to 17 years old, in which the neoplastic cell population was sampled. Additionally, multiple sites within a given cases were sampled to determine clonality of the tumor cell population. Polymerase chain reaction and subsequent sequence analysis of the K-ras-2 exon-1 gene was used for mutation analysis. Focal weak staining with p53 IHC was observed in 4 of 13 (31%) MS and 10 of 13 (77%) TS cases, with all remaining cases being negative (P < .05). Only one MS case (8%) showed K-ras mutation (codon 13 GGC > GAC; glycine > aspartate), which is in contrast to 2 of the TS cases (15%), showing codon 12 mutations. All the remaining cases were wild type. Therefore, primary mediastinal seminomas appear to be different in their K-ras sequence and p53 immunostain profile from TS. Codon mutation type may be useful in determining primary versus metastatic origin of a mediastinal seminoma.

Adolescent↗
PubMed1996

Pleomorphic (giant and spindle cell) carcinoma is genetically distinct from adenocarcinoma and squamous cell carcinoma by K-ras-2 and p53 analysis.

Pleomorphic carcinoma (PC) of lung is a poorly differentiated epithelial neoplasm predominantly composed of pleomorphic giant and/or spindle tumor cells. The WHO classification of lung cancer recognizes spindle cell carcinoma and giant cell carcinoma as separate neoplasms related to squamous cell carcinoma (SqC) and large cell carcinomas, respectively. Further, the presence of foci of SqC or adenocarcinoma (AdC) in, respectively, 10% and 45% of PC produces additional uncertainty as to the distinctive nature of this tumor type. In this study, the authors tested the hypothesis that PC is an entity separate from SqC or AdC by evaluating the mutational spectrum seen in these tumor types. This is performed by documenting and comparing mutation type and rate of K-ras-2 and p53 genes in PC, SqC, and AdC. Comparative DNA sequence and immunohistochemical analysis were performed on 22 PC, 42 SqC, and 97 AdC. Archival formalin-fixed, paraffin-embedded tissues formed the basis of the study. Immunohistochemical staining with p53 antibody (DO-7) revealed statistically significant differences in the intensity and frequency of staining of PC (weak, 86% of cases) versus SqC (strong, 52% of cases) and AdC (strong, 27% of cases) (P < .001). Topographic genotyping with subsequent polymerase chain reaction (PCR) and sequence analysis of K-ras-2 showed mutations in significantly fewer cases of PC (9%, 2 of 22 cases) than in AdC (36%, 35 of 97 cases) or SqC (0%, 0 of 42 cases) (P < .001). Pleomorphic carcinoma also showed significantly fewer p53 point mutations (14%, 3 of 22 cases) than did AdC (27%, 26 of 97 cases) of SqC (43%, 18 of 42 cases) (P < .01). Finally, the p53 mutations in PC were more common in exon 7, whereas those in SqC and AdC were more frequent in exon 8. These findings reveal significant differences in the pattern and frequency of genetic mutations between PC and pulmonary SqC and AdC and are in keeping with the separate histopathologic classification of these tumors.

Adenocarcinoma↗
PubMed1996

Pleomorphic large cell lymphomas of the mediastinum.

Nine cases of primary non-lymphoblastic, non-Hodgkin's large cell lymphomas of the mediastinum characterized by a highly pleomorphic histologic appearance are described. The patients, four women and five men, were aged 30 to 65 years. All patients presented with symptoms referable to their tumors, including cough, chest pain, dyspnea, pleural effusion, and superior vena cava syndrome. Clinical and pathologic staging in all patients showed that the bulk of the tumor was confined to the chest cavity at the time of initial diagnosis, with local infiltration into the neck, lung hilum, and surrounding mediastinal structures. Three different histological growth patterns were observed: one composed of a diffuse proliferation of pleomorphic, highly atypical cells with bizarre nuclear features that closely resembled a high grade sarcoma; another one composed of sheets of large, epithelial-appearing atypical cells suggestive of anaplastic carcinoma; and another pattern characterized by a pleomorphic proliferation of large lymphoid cells admixed with numerous scattered Reed-Sternberg-like cells reminiscent of the lymphocyte-depleted variant of Hodgkin's disease. Immunohistochemical studies on paraffin-embedded tissue sections in all cases showed positive staining of the tumor cells with CD20 and CD45 antibodies and negative staining with a large panel of markers, including broad-spectrum keratin, CAM 5.2, carcinoembryonic antigen, epithelial membrane antigen, vimentin, actin, desmin, HMB 45, S-100 protein, CD3, CD15, CD30, and CD45RO. Because of their location restricted to the anterior mediastinum, frequent lack of recognizable lymph node architecture, and bizarre cytologic features, the present group of lesions posed difficulties for diagnosis, their correct identification was achieved through the application of a panel of immunohistochemical markers. An awareness of these unusual histologic appearances of primary large cell lymphoma in the mediastinum and inclusion of a broad panel of lymphoid markers are therefore recommended for the evaluation of pleomorphic, undifferentiated malignant neoplasms of this anatomic region.

Adult↗
PubMed1996

Primary thymic epithelial neoplasms showing combined features of thymoma and thymic carcinoma. A clinicopathologic study of 22 cases.

Thymic epithelial neoplasms are unusual tumors that may span the gamut from clinically benign, well-differentiated lesions (encapsulated thymoma) to overtly malignant, poorly differentiated neoplasms (thymic carcinoma). It has been commonly believed that lesions displaying obvious cytologic features of malignancy (i.e., thymic carcinoma) represent a unique and separate group that is histogenetically distinct from thymoma. We have studied 22 cases of thymic epithelial neoplasms characterized by the admixture of areas displaying conventional features of thymoma with areas showing features of thymic carcinoma. The tumors occurred in six women and 16 men whose ages ranged from 23 to 83 years (median, 53). The lesions presented in eight patients with symptoms of chest discomfort resulting from the involvement of surrounding structures; in 14 patients, they were asymptomatic and discovered incidentally on routine chest radiographs. Histologically, most tumors showed a combination of conventional thymomatous elements with well-differentiated squamous-cell carcinoma (10 cases), followed by thymoma and poorly-differentiated squamous carcinoma (seven cases) and spindle-cell thymoma with poorly-differentiated squamous carcinoma (five cases). Areas of transition between the two different components could be identified in most cases. In five cases, areas showing the features of clear-cell carcinoma could be seen either arising from squamous carcinomatous elements or within the thymomatous component, and in one case transitions between lymphoepithelioma-like carcinoma and anaplastic carcinoma could be observed. Two patients had a history of myasthenia gravis with biopsy-proven thymomas in whom the tumors had been monitored without treatment for 10 and 14 years before the sudden enlargement of the mass. The resected specimens in both patients showed the emergence of a carcinoma arising from a thymoma. The present cases appear to support the existence of a continuum in the spectrum of differentiation between thymoma and thymic carcinoma, suggesting a close histogenetic relationship between these two conditions. Such findings are important not only for our understanding of these tumors but may also play a significant role in the assessment of the biologic behavior and management of these lesions.

Adult↗
PubMed1996

Primary thymic carcinomas.

Primary thymic epithelial neoplasms are unusual tumors that have been the subject of much interest and debate, and their natural behavior has been difficult to determine. In this chapter the authors review current concepts on the classification and criteria for diagnosis of thymic carcinoma.

Carcinoma↗
PubMed1995

Mediastinal hemangiomas: a study of 18 cases with emphasis on the spectrum of morphological features.

A study of 18 cases of mediastinal hemangiomas is presented. The patients were eight women and 10 men between the ages of newborn to 74 years. Clinically, the most common symptoms included dyspnea, cough, and chest pain. In one patient the mediastinal hemangioma was associated with another hemangioma in the gastrointestinal tract and presented initially with gastrointestinal bleeding. Four patients were asymptomatic. Anatomically, 14 tumors were located in the anterior mediastinum and four in the posterior mediastinum. Surgical resection was the treatment of choice for all patients. Grossly, the lesions were described as well circumscribed, cystic, hemorrhagic tumors that ranged in size from 2 cm to 20 cm in diameter. Histologically, the tumors were divided into two groups, one showing the features of capillary hemangioma characterized by a lobular and solid growth pattern featuring dilated small vessels and a solid proliferation of endothelial cells and another group showing the features of cavernous hemangioma characterized by large dilated vascular spaces with areas showing interstitial inflammatory changes, fibrosis, and smooth muscle proliferation. A few tumors were characterized by prominent regressive changes, including stromal hyalinization, dystrophic ossification, cystic and perivascular myxoid changes, and extensive fatty overgrowth. Some of the tumors showed extreme cellularity with virtual obliteration of vascular lumina due to compression by tumor cells and focal mitotic activity similar to that observed in cutaneous juvenile hemangiomas. Despite their large size, often infiltrating appearance, and sporadic mitotic activity, follow-up ranging from 1 month to 4 years in 11 patients showed all to be alive and well, thus demonstrating the benign nature of these neoplasms. A discussion of the differential diagnosis and a review of the literature on these rare tumors are presented.

Adolescent↗
PubMed1995

Primary pulmonary sarcomas with features of monophasic synovial sarcoma: a clinicopathological, immunohistochemical, and ultrastructural study of 25 cases.

We present 25 cases of a primary pulmonary sarcoma bearing histological, immunohistochemical, and ultrastructural features indistinguishable from those of monophasic synovial sarcoma of soft tissue. The patients were 11 men and 14 women between the ages of 16 and 77 years. Clinically, the most common symptoms were chest pain, cough, shortness of breath, and hemoptysis. The lesions involved all lung segments. Grossly, they varied in size from 0.6 to 20 cm and were described as soft to rubbery tumors with areas of necrosis and hemorrhage, some with cystic changes. Two lesions involved the bronchial wall and in one case the tumor was described as encircling the bronchial tree. Histologically, all of the lesions were characterized by an atypical spindle cell proliferation with a solid growth pattern. Areas of myxoid, neural, hemangiopericytic, and epithelial-like growth pattern were observed. Mitoses, necrosis, and hemorrhage were seen in all lesions in varying proportions. Immunohistochemical studies for epithelial membrane antigen (EMA) and keratin showed strong focal positivity in 25 of 25 and 23 of 25 lesions, respectively. Immunohistochemical study for vimentin showed diffuse strong positivity in all lesions. Other immunostains, including desmin, smooth muscle actin, and S-100 protein, were negative. Electron microscopy in three cases showed spindle cells with elongated nuclei containing abundant cytoplasmic rough endoplasmic reticulum and well developed desmosome type intercellular junctions. Follow-up information ranging from 2 to 20 years was obtained in 18 patients. Six patients died of their tumors, whereas four patients died of unrelated causes without evidence of recurrence or metastases. Eight patients were alive with disease (recurrence and/or metastases) from 1 to 7 years after diagnosis. Four patients were alive and well without evidence of recurrence or metastases from 2 to 20 years (mean follow-up, 12.5 years). The present group of lesions appears to constitute a distinctive and as yet previously undescribed primary sarcoma of the lung, which probably represents the visceral counterpart of monophasic synovial sarcoma of soft tissue in a pulmonary location. Because of their distinctive biology these lesions should be distinguished from a variety of primary and metastatic malignancies of the lung.

Adolescent↗
PubMed1995

Chordomas of the mediastinum: clinicopathologic, immunohistochemical, and ultrastructural study of six cases presenting as posterior mediastinal masses.

Six cases of chordomas presenting as primary posterior mediastinal tumors are described. Three patients were female, and three were male between the ages of 8 and 65 years (mean, 40.6 years). In all cases, the tumors presented radiographically as relatively well-circumscribed, encapsulated soft tissue masses that did not seem to be related to the thoracic or dorsal spine. Only in one case, focal infiltration of bone at the level of T6-T7 was observed at the time of surgery. Histologically, the lesions showed a spectrum of features that ranged from sheets and cords of large cells with abundant vacuolated cytoplasm to small, stellate cells embedded within an abundant mucoid matrix. In one case, the cell population showed more pronounced nuclear atypia with loss of cytoplasmic vacuolization, frequent mitotic figures, necrosis, and solid areas characterized by a perivascular distribution of atypical spindle cells set against a myxoid stroma. Another case showed features of chondroid chordoma, with an immature chondroid-appearing matrix surrounding the atypical tumor cells. Immunohistochemical studies in all cases showed positive staining of the tumor cells with CAM 5.2 and broad-spectrum keratin, epithelial membrane antigen (EMA) and vimentin, and, to a lesser extent, with S-100 protein. Stains for muscle actin, carcinoembryonic antigen (CEA), and desmin were negative. Ultrastructural examination in two cases showed a spectrum of features that varied from large cells with abundant cytoplasm containing scattered ribosomes, glycogen granules, Golgi apparatti, abundant intermediate filaments, and small lumen formation with immature microvilli to smaller cells with elongated cytoplasmic processes, fewer intermediate filaments, rare desmosome type intercellular junctions, and complexes of mitochondria/rough endoplasmic reticulum. On clinical follow-up, two patients died with metastases to the lungs, chest wall, and liver from 1 to 3 years after diagnosis, and two patients are alive and well without evidence of disease after 3 and 16 years. Chordoma should be entertained in the differential diagnosis of posterior mediastinal tumors. Application of immunohistochemical stains or electron microscopy will be of aid in separating them from other conditions that may histologically closely resemble these lesions.

Adolescent↗