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Biomedical subjects

C A Moran

Publications and source records attributed to C A Moran.

At least 55 records · Page 3Linked to original sources

Dendritic fibromyxolipoma: clinicopathologic study of a distinctive benign soft tissue lesion that may be mistaken for a sarcoma.

Twelve cases are described of a distinctive benign soft tissue lesion that may be mistaken for a sarcoma. The tumors occurred in 11 men and a woman aged 33 to 81 years (mean, 64 years), and measured from 2 to 11 cm in greatest diameter (mean, 6 cm). They were grossly described as soft, well-circumscribed, yellow-gray, with a mucoid cut surface. All cases were superficially located in the subcutis or muscular fascia of the head and neck region or the chest and back. Histologically, the tumors were characterized by a proliferation of spindle or stellate fibroblastic cells variably admixed with mature adipose tissue embedded in an abundant myxoid and collagenized stroma. The spindle and stellate fibroblastic cells were characterized by slender dendritic prolongations of their cytoplasm, which appeared to extend for short distances along connective tissue planes. Electron microscopy in two cases confirmed the dendritic nature of the fibroblastic cells, which showed elongated cytoplasmic processes lacking external lamina and displaying foci of pinocytotic activity. Immunohistochemical studies in 11 cases showed strong positivity of the spindle cells with vimentin, CD34 and bcl-2, and negative staining for smooth muscle actin, muscle-specific actin (HHF35), desmin, S-100 protein, keratin, and EMA. Because of their prominent myxoid stroma and relatively large size, some of these tumors were initially misinterpreted as low-grade sarcomas. Clinical follow-up in five cases, however, showed that the patients were alive and well without evidence of recurrence between 5 and 13 years (mean follow-up, 8 years) after simple local excision. The present cases appear to represent a distinctive form of benign soft tissue neoplasm that should be distinguished from myxoid liposarcoma and other benign and malignant myxoid tumors of superficial soft tissues.

Adult↗

Primary cutaneous synovial sarcoma: a case report.

We present a case of synovial sarcoma involving the cutaneous tissue of the knee in an 18-year-old woman. The 2.5 cm tumor was locally excised and recurred six times over the following 24 years. The neoplasm involved the deep dermis with extension into the papillary dermis and superficial subcutis. The tumor was predominantly composed of spindle cells arranged in compact interdigitating fascicles and scattered epithelial nests were seen. Focal myxoid and hemangiopericytoma-like areas as well as numerous mast cells were identified. Spindle cells stained for vimentin, CAM 5.2, and epithelial membrane antigen, whereas epithelial nests only stained for CAM 5.2 and epithelial membrane antigen. Neither component was reactive for antibodies directed against desmin, muscle specific actin, smooth muscle actin, S-100 protein, CD-31, or CD-34. This newly reported location for this morphologically heterogeneous tumor creates potential diagnostic confusion with other primary neoplasms in these areas.

Adolescent↗

Expression of bcl-2 oncoprotein in benign and malignant spindle cell tumors of soft tissue, skin, serosal surfaces, and gastrointestinal tract.

An immunohistochemical study to determine the pattern of immunoreactivity for bcl-2 oncoprotein was performed in 380 spindle cell tumors of soft tissue, skin, serosal surfaces, and gastrointestinal tract. The cases studied included examples of benign, reactive spindle cell proliferations to benign and malignant spindle cell neoplasms, including nodular fasciitis (10), fibromatosis (5), dermatofibroma (10), dermatofibrosarcoma protuberans (18), Kaposi's sarcoma (15), spindle cell lipomatous tumors (24), benign and malignant smooth muscle tumors (35), neural/peripheral nerve sheath neoplasms (53), synovial sarcomas (70) solitary fibrous tumors of serosal surfaces and other sites (56), gastrointestinal stromal tumors (GIST) (47), and malignant undifferentiated fibroblastic spindle cell proliferations of soft tissue (37 cases). The results of bcl-2 staining was additionally correlated with CD34 immunoreactivity. Bcl-2 was uniformly negative in all cases of nodular fasciitis, fibromatosis, and dermatofibroma, as well as in benign and malignant smooth muscle proliferations. Strong positivity for bcl-2 was observed in all cases of spindle cell lipoma, dendritic fibromyxolipoma, Kaposi's sarcoma, solitary fibrous tumors, gastrointestinal stromal tumors, and in the spindle cell component of synovial sarcoma. With the exception of the last, there appeared to be a close correlation between the expression of bcl-2 and CD34 in these tumors. Strong bcl-2 positivity also was found, at least focally, in approximately one third of benign and malignant peripheral nerve sheath tumors, particularly in the better-differentiated (Antoni type A) areas. Sarcomas of fibroblastic type, including low-grade myxofibrosarcoma, malignant fibrous histiocytoma, and fibrosarcoma, showed variable expression of bcl-2 in the tumor cells. Our results appear to indicate that bcl-2 may have a wide distribution among benign and malignant spindle cell neoplasms. Strong expression of this marker in some of these conditions, particularly solitary fibrous tumor, gastrointestinal stromal tumors, and synovial sarcoma, may be of aid for differential diagnosis.

Antigens, CD34↗

Germ-cell tumors of the mediastinum.

Germ-cell tumors occurring primarily in the mediastinum have been well recognized in the literature for many years. Unfortunately, most of what has been written on these tumors has been in the form of case reports and small series of cases, thus precluding a better understanding of their clinical and demographic features, as well as of their biologic behavior in this particular location. In addition, mediastinal germ-cell tumors not only have never had a standardized nomenclature, but they also have lacked the benefit of a clinical staging scheme for assessment of prognosis. Another important aspect of these tumors that has required attention is the frequency with which teratomatous lesions are associated with malignant components in the mediastinum. Comprehensive studies of mediastinal germ-cell tumors to determine whether these lesions recapitulate the distribution, histopathologic features, and biologic behavior of their counterparts in other areas, such as the gonads, have been lacking for many years. In this article, we review our experience with a large series of cases of primary mediastinal germ cell tumors and examine recent concepts and advances in our understanding of these unusual and diagnostically challenging neoplasms.

Biomarkers, Tumor↗

Primary pulmonary glomus tumor: a clinicopathologic and immunohistochemical study of two cases.

We present two cases of glomus tumors arising within the lung parenchyma. The patients are a 40-year-old man and a 51-year-old man. Clinically, the two men were asymptomatic, and the pulmonary tumor was detected during a routine chest roentgenographic examination. Complete surgical resection of the pulmonary tumors was performed. Grossly, the tumors measured 1.1 and 1.5 cm. in greatest dimension; they were well circumscribed and subpleural. Neither tumor showed evidence of invasion of lung or pleura. Histologically, both tumors had pseudocapsules, lacked invasion of surrounding lung structures, and demonstrated the appearance of the solid/mucohyaline, or "glomus tumor proper" type of neoplasm. This included oval-to-round cells, with central uniform nuclei; variably eosinophilic-to-clear cytoplasm; and well-demarcated cell borders in close proximity to a rich vascular supply showing perivascular fibrosis. Immunohistochemically, both tumors showed diffuse, moderate-to-strong staining for vimentin, muscle-specific actin, and smooth muscle actin. One tumor also showed diffuse strong staining for desmin, whereas the other was negative. Follow-up information obtained from one of the patients revealed that he was alive and well 47 months after surgical resection. Our cases highlight the ubiquitous distribution of glomus tumor and its similar histologic appearance and immunohistochemical profile to soft tissue glomus tumors.

Actins↗

Primary germ cell tumors of the mediastinum: II. Mediastinal seminomas--a clinicopathologic and immunohistochemical study of 120 cases.

BACKGROUND: Primary seminomas of the mediastinum are unusual neoplasms that are morphologically indistinguishable from their gonadal counterparts but may have different biologic behavior because they arise at this particular location. METHODS: The clinical and pathologic features in 120 cases of primary mediastinal seminoma were reviewed, and the immunohistochemical staining patterns in 50 of these tumors were also analyzed. RESULTS: The patients were all men between the ages of 14 and 79 years (mean age, 46.5 years). Their clinical symptoms included cough, chest pain, and dyspnea. In some patients, the lesions were asymptomatic and discovered incidentally on routine chest radiographs. None of the patients had a previous history of testicular neoplasm or tumor elsewhere. Macroscopically, the tumors were described as soft and tan, with a slightly lobulated cut surface, and measured up to 16 cm in greatest dimension. Histologically, the morphologic features were similar to those of tumors occurring in the gonads, namely, a neoplastic proliferation of round-to-polygonal cells with indistinct cell borders, clear-to-lightly-eosinophilic cytoplasm with round-to-oval nuclei and prominent nucleoli, associated with a prominent inflammatory background composed mainly of mature lymphocytes. Necrosis, hemorrhage, multinucleated giant cells, granulomatous reaction, and remnants of thymic tissue were observed in a variable number of cases; mitoses were rare. Immunohistochemical studies in 50 cases showed cytoplasmic staining with placental alkaline phosphatase in 80% of the tumors, focal dotlike positivity for CAM 5.2 low-molecular-weight keratins in 75%, focal cytoplasmic staining for wide-spectrum keratin in 70%, focal positive reaction with vimentin in 70%, and focal positivity with HCG in singly scattered cells in 5%. Immunostains for carcinoembryonic antigen, epithelial membrane antigen, and alpha-fetoprotein were negative in all the cases studied. Fifty patients were Stage I, 3 patients were Stage II, and 12 patients were Stage III. Clinical follow-up information was obtained for 65 cases (54%). Forty-nine patients were alive and disease free after a period ranging from 1 to 19 years (mean follow-up, 10 years). Sixteen patients died within the same period and were found to have metastases to distant organs. Of the 16 patients who died, 6 showed extension of the tumor outside of the mediastinal compartment at the time of initial diagnosis (Stage III lesions). Aside from clinical staging, the authors' findings also suggest that patients >37 years have worse outcomes than younger individuals. The authors were unable to find any correlation between histopathologic features and clinical behavior in any of these cases. CONCLUSIONS: Clinical and pathologic staging of mediastinal seminomas are important parameters that can be useful in determining the clinical outcomes of patients with these tumors. Tumor invasion into adjacent organs represents a marker of increased morbidity and mortality. The authors' findings suggest that patients with mediastinal seminomas may have a very good prognosis when the diagnosis is made early; patients with more advanced lesions may require more aggressive therapy for improved local control and prevention of distant metastases.

Adolescent↗

Primary germ cell tumors of the mediastinum: I. Analysis of 322 cases with special emphasis on teratomatous lesions and a proposal for histopathologic classification and clinical staging.

BACKGROUND: Primary germ cell tumors of the mediastinum are unusual neoplasms with histopathologic features that are similar to those of germ cell tumors in the gonads. However, their clinical features, behavior, and spectrum of pathologic features in the mediastinum have not yet been fully defined. METHODS: The clinical and pathologic features of 322 cases of primary mediastinal germ cell tumors were reviewed, with special emphasis on teratomatous lesions. The tumors were divided into groups according to their histologic features and correlated with their order of frequency, patient gender and age distribution, and morphologic features. A clinical staging scheme based on the extent and location of the lesions was devised. RESULTS: The overwhelming majority of patients were men (320); only 2 were women (both had teratomatous lesions with additional malignant components). The patients' ages ranged from 1 to 79 years (mean, 40 years). Histologically, all types of germ cell tumors were represented, including 138 teratomas (87 mature teratomas, 6 immature teratomas, and 45 teratomas with additional malignant components); 120 seminomas; 52 nonseminomatous, nonteratomatous germ cell tumors (38 yolk sac tumors, 6 embryonal carcinomas, and 8 choriocarcinomas); and 12 combined germ cell tumors without teratomatous components. The teratomatous lesions with additional malignant components were further separated into subtypes based on the histologic types of their malignant components, i.e., epithelial, mesenchymal, etc. Clinical staging was possible in 242 cases, with 191 cases (79%) in Stage I, 4 cases (1.6%) in Stage II, and 47 cases (19.4%) in Stage III. In each group, the clinical staging correlated well with the clinical outcome for the majority of patients. CONCLUSIONS: The results of this study showed that mediastinal germ cell tumors have demographic and histopathologic distributions similar to those of tumors occurring in the male gonads, with teratomatous and seminomatous lesions being the most common. Among the nonseminomatous germ cell tumors in this study, the yolk sac tumors appeared to occur the most frequently (the ratio of yolk sac tumor occurrence to embryonal carcinoma occurrence was 6.1:1). In addition, the subclassification of teratomas with additional malignant components based on the histologic types of malignancies may lead to more therapy choices for patients. At the same time, the use of a clinical staging scheme may be of value in predicting clinical outcome and planning therapy.

Adolescent↗

Primary germ cell tumors of the mediastinum: III. Yolk sac tumor, embryonal carcinoma, choriocarcinoma, and combined nonteratomatous germ cell tumors of the mediastinum--a clinicopathologic and immunohistochemical study of 64 cases.

BACKGROUND: Yolk sac tumor (YST), embryonal carcinoma (EC), choriocarcinoma (CC), and combined germ cell tumors (CGCTs) of the mediastinum are uncommon neoplasms. Only sporadic cases have been documented in the literature; therefore, the clinical behavior of these tumors when located in the mediastinum remains relatively unknown. METHODS: The clinical and pathologic features of 64 cases of primary YST, EC, CC, and CGCTs without teratomatous components were reviewed. The immunohistochemical findings in 29 cases were also analyzed using a panel of monoclonal and polyclonal antibodies in formalin fixed, paraffin embedded tissues. RESULTS: The patients were all men between the ages of 14 and 63 years (mean, 38.5 years). Their clinical symptoms included chest pain, shortness of breath, chills, fever, and superior vena cava syndrome. None of the patients had a previous history of testicular neoplasm or tumor elsewhere. Macroscopically, the lesions in 27 patients were described as large, soft, hemorrhagic, and in some cases necrotic, and varied in greatest dimension from 6 to 20 cm. Histologically, the tumors displayed morphologic features similar to those of their gonadal counterparts. Pure YSTs accounted for the majority of cases in this series (38 of 64, 60%), followed by pure CCs (8 of 64, 12%) and pure ECs (6 of 64, 9%). CGCTs accounted for only 18% of the total cases (12 of 64). YSTs showed a variety of growth patterns; however, the reticular pattern was the most commonly observed. ECs showed a more solid growth pattern with marked pleomorphism of the tumor cells and abundant areas of necrosis. CCs were characterized by the presence of cytotrophoblastic and syncytiotrophoblastic elements with frequent areas of necrosis and hemorrhage. The cases of nonteratomatous CGCT consisted of 5 cases of EC + YST, 2 cases of EC + seminoma, 4 cases of YST + seminoma, and 1 case of EC + CC. In clinical staging, 14 patients were Stage I, 6 were Stage II, and 19 were Stage III. Information on follow-up ranging from 1 month to 13 years was available for 40 patients. Seventeen patients with YST died of their tumors. Of these, 10 who presented with Stage III disease died within the first 2 years. Unfortunately, no clinical staging was obtained for the other 7 patients in this group, and they died within 6-36 months. It is noteworthy that 4 patients with YST have survived for more than 2 years; these patients presented in Stages I and II, and 2 of them received aggressive therapy with chemotherapeutic agents and radiation. Two patients with Stage III EC died within 2 years. The remaining 4 patients with EC were lost to follow-up. Eight patients with CC died within 6 months after initial diagnosis; 7 of them presented Stage III disease and only 1 presented with Stage I. In the nonteratomatous CGCT category, 2 patients with EC + YST died within 2 years after initial diagnosis, whereas 3 patients with YST + seminoma were alive after 4-9 years. CONCLUSIONS: The results of this study confirm the aggressive nature of primary nonseminomatous germ cell tumor of the mediastinum; 72% of the patients with adequate follow-up died of their tumors within 6-36 months after diagnosis, despite aggressive therapy. Clinical and pathologic staging of mediastinal YST, EC, and CGCT are important parameters that may be helpful in predicting the clinical outcomes of patients with these tumors. The authors' findings suggest that the majority of tumors that are not limited to the mediastinum at the time of diagnosis have more aggressive behavior. On the other hand, mediastinal choriocarcinomas appeared to follow a very aggressive clinical course, regardless of treatment modality or clinical tumor stage.

Adolescent↗

Pigmented extraadrenal paragangliomas. A clinicopathologic and immunohistochemical study of five cases.

BACKGROUND: Pigmented extraadrenal paragangliomas are unusual neoplasms that have rarely been reported in the literature. METHODS: The clinical, pathologic, and immunohistochemical features of five cases of pigmented extraadrenal paragangliomas were reviewed. RESULTS: The patients were 2 women and 3 men within the ages of 17 and 56 years (mean age: 36.5). Two neoplasms were located in the lumbar spine, one in the urinary bladder, one in the anterior mediastinum, and one in the retroperitoneum. Clinically, one patient with spinal paraganglioma presented with symptoms of numbness and weakness of the lower extremities whereas the second patient had low back pain of several weeks' duration. The paraganglioma of the bladder occurred in a pregnant woman who had symptoms of dysuria and microscopic hematuria whereas the patient with an anterior mediastinal tumor presented with chest pain. No clinical history was obtained from the patient with the retroperitoneal tumor. None of the patients had a history of hypertension. Grossly, the tumors were described as well-circumscribed, soft, and slightly hemorrhagic, and measured from 2 to 9 cm in greatest dimension. Histologically, the five tumors displayed characteristics similar to those described in these tumors, mainly the presence of an organoid or zellballen growth pattern. In addition, they contained moderate amounts of intracellular melanin pigment that focally obscured the true nature of the lesion. Immunohistochemically, four cases were positive for chromogranin whereas S-100 protein was detected in the sustentacular cells in four cases. Follow-up information ranging from 6 months to 18 years for 3 patients revealed that the patients were alive and well without recurrence or metastasis. One patient with spinal paraganglioma was lost to follow-up, and the patient with mediastinal paraganglioma was a recent case and therefore the behavior of the paraganglioma could not be assessed. CONCLUSIONS: The current study expands the morphologic spectrum of extraadrenal paragangliomas and emphasizes the need to consider these tumors in the differential diagnosis of pigmented neoplasms. These findings suggest that the presence of melanin pigment does not alter the behavior of these neoplasms.

Adolescent↗

Malignant cartilaginous tumors of the mediastinum: clinicopathological study of six cases presenting as extraskeletal soft tissue masses.

Cartilage and bone-forming tumors of the mediastinum are extremely rare neoplasms with very few cases having been reported in the literature. We studied six cases of primary malignant cartilaginous tumors presenting as extraskeletal soft tissue masses in the posterior mediastinum. The patients were five women and one man aged 11 to 63 years (median, 31 years). Histologically, the lesions showed a spectrum of features that ranged from mesenchymal chondrosarcoma, to extraskeletal myxoid chondrosarcoma, to moderately well to poorly differentiated chondrosarcoma. In all cases, the lesions presented as well-circumscribed tumor masses centered in the soft tissues in the posterior mediastinum without radiographic evidence of origin from bone. Because of their relatively small size, good circumscription, focal areas of calcification, and posterior mediastinal location, the preoperative clinical diagnoses included benign neurogenic tumor and neuroblastoma. All of the lesions were treated by complete surgical excision, followed in two cases by postoperative radiation therapy. Clinical follow-up was available in five cases: two patients with mesenchymal chondrosarcoma presented with local recurrence after 3 and 7 years, one developed metastases to the sacrum 8 years after initial diagnosis and died, and one was alive and well without evidence of disease after 6 years. The patient with myxoid chondrosarcoma of the posterior mediastinum developed bilateral pulmonary metastases 10 months after surgery and has been lost to follow-up since. Our findings reinforce previous observations on the occurrence of extraskeletal cartilaginous tumors in the mediastinum and indicate that these tumors can show a propensity for local aggressive behavior with high recurrence rate and a definite potential for distant metastases. Such tumors should be considered in the differential diagnosis of malignant neoplasms presenting as a soft tissue mass in the posterior mediastinum.

Adolescent↗

Epithelial-myoepithelial carcinoma of the lung: immunohistochemical and ultrastructural observations and review of the literature.

Epithelial-myoepithelial carcinoma is a rare low-grade malignant salivary gland neoplasm that most commonly occurs in the parotid gland but can also arise in minor salivary glands. We report a case of a primary epithelial-myoepithelial carcinoma of the lung. The patient is a 55-year-old black woman who presented with increasing shortness of breath and productive cough of at least 3 months duration. A left lower lobe endobronchial lesion was identified radiographically. Surgical resection of the lesion was performed, obtaining a circumscribed, nonencapsulated 3.9 cm tan mass which was attached to the inner wall of the lateral basal segment bronchus. A biphasic proliferation of epithelial (cytokeratin positive; S-100 protein and muscle-specific actin negative) and myoepithelial (S-100 protein and muscle-specific actin positive with focal weak cytokeratin positive) cells was identified by immunohistochemical and ultrastructural analysis of formalin-fixed tissue. The patient is disease free 7 months after resection. Pulmonary epithelial-myoepithelial carcinoma likely derives from the submucosal bronchial glands and should be added to the growing list of salivary gland-type neoplasms that may occur as primary pulmonary neoplasms. Because its histology is identical to salivary epithelial-myoepithelial carcinoma, pulmonary epithelial-myoepithelial carcinoma should be considered a low-grade malignant neoplasm and should be designated as epithelial-myoepithelial carcinoma is preference to other terms that may not convey its malignant potential. Although follow-up on reported cases is limited, lobectomy with negative bronchial margin should be curative.

Carcinoma↗

Inflammatory pseudotumor of lymph nodes: a study of 25 cases with emphasis on morphological heterogeneity.

The clinicopathological and immunohistochemical findings in 25 cases of inflammatory pseudotumor of lymph nodes (IPT) are presented. The patients were 13 women and 12 men between 8 and 81 years of age. Clinically, symptoms of prior infection, fatigue, abdominal pain, weight loss, fever of unknown origin, pelvic inflammatory disease, or nausea and night sweats were obtained in 15 patients, whereas six patients presented with asymptomatic lymphadenopathy. In four additional patients, no clinical information was obtained. The involved nodes included cervical, supraclavicular, inguinal, mesenteric, and mediastinal lymph nodes. In two cases, there was synchronous involvement of separate lymph node groups (inguinal and cervical in one case and cervical and mediastinal in another case), whereas in a third patient there was synchronous involvement of the spleen and a paraaortic lymph node. Histologically, the lesions were characterized by a fibrosing/inflammatory process that showed marked heterogeneity and striking variation from case to case. Based on their histological features, the lesions could be classified into three different groups: Stage I was characterized by the appearance of single or multiple small foci containing a spindle cell proliferation admixed with a prominent inflammatory background, with complete preservation of the remainder of the nodal architecture; stage II was characterized by more diffuse involvement of the lymph node with a marked inflammatory response admixed with a prominent myofibroblastic proliferation leading to subtotal effacement of the nodal architecture, often with extension of the process beyond the capsule into perinodal fat; and stage III was characterized by almost complete replacement of the lymph node by diffuse sclerosis with scant residual inflammatory elements and total loss of the normal nodal architecture. Immunohistochemical studies in 20 cases showed a striking number of vimentin- and actin-positive myofibroblastic cells with moderate increase in CD20/CD45+ small lymphocytes and polyclonal plasma cells in the stage I lesions, the emergence of numerous CD68+ histiocytes admixed with lymphocytes, plasma cells, and abundant fibromyofibroblastic cells in the stage II lesions, and only few remaining scattered CD68+ histiocytes and fibroblasts in the stage III lesions. Our findings suggest that inflammatory pseudotumor of lymph node represents an evolving, dynamic process that may adopt different morphological appearances depending on its stage of evolution. Recognition of the various stages of this process may be of importance for differential diagnosis with other fibrosing/inflammatory conditions of lymph nodes.

Actins↗

Primary spinal paragangliomas: a clinicopathological and immunohistochemical study of 30 cases.

AIMS: Extra-adrenal paragliomas are neoplasms which have been the subject of much debate regarding parameters to establish their biological behaviour. This study describes the clinicopathological and immunohistochemical features of 30 cases of spinal paragliomas. METHODS AND RESULTS: There were 15 male and 15 female patients. The median age at diagnosis was 46 years (range 20-74 years). Fourteen patients presented with back pain, two with numbness of the lower extremities, one with difficulty in walking and one with spinal cord compression. Nineteen tumours were located in the lumbar region, six in the cauda equina, two in the filum terminale, two in the thoracic region and one in the cervical region. All patients underwent gross total excision. The size of the tumours ranged from 10 to 50 mm. Histologically, 18 neoplasms showed alveolar (Zellballen) pattern, seven a spindle component, two eosinophilic granular cells suggestive of oncocytic metaplasia, two melanin pigment and one ganglion cells. Positive immunohistochemical results include: neuron-specific enolase 23/23 (100%), synaptophysin 21/23 (91%), S100 protein 22/23 (95%, sustentacular cells), leu-enkephalin 11/23 (47%), somatostatin 8/23 (34%), focal glial fibrillary acidic protein 7/23 (30%), focal keratin 5/23 (21%), neurofilament proteins 3/23 (13%) and adrenocorticotrophic hormine (ACTH) 1/23 (4%). Follow-up information obtained in 20 patients show 17 patients alive over a period of 6-216 months. One patient had bone metastases. Two patients died of unrelated causes, including one of congestive heart failure and one of myocardial infarction. CONCLUSIONS: In our experience, spinal paragangliomas behave as slow-growing tumours susceptible to potential cure by total excision. We agree with the current World Health Organization (WHO) classification as grade I tumours. Less than 1% may be locally aggressive. Spinal paragangliomas immunoreact not only for conventional neuroendocrine markers but also for peptides including somatostatin and ACTH and focally for the epithelial marker keratin.

Adult↗

Primary alveolar soft-part sarcoma of the mediastinum: a clinicopathological and immunohistochemical study of two cases.

AIMS: Primary alveolar soft part sarcomas originating within the thoracic cavity are rare. The cases herein described highlight the ubiquitous distribution of this neoplasm and the importance of considering this tumour in the differential diagnosis of mediastinal tumours. METHODS AND RESULTS: Two cases of alveolar soft-part sarcoma of the mediastinum are presented. The patients are two men of 22 and 23 years of age. Clinically, the patients presented with symptoms of chest pain. One tumour was in the anterior mediastinum while the second tumour was in the posterior mediastinum. Even though the bulk of the tumours were in mediastinal locations, both patients had pulmonary metastases at the time of diagnosis. Histologically, both tumours showed the classic morphology of alveolar soft part sarcoma, i.e. a proliferation of large polygonal cells with round to oval nuclei, prominent nucleoli and moderate amounts of eosinophilic cytoplasm arranged in a prominent alveolar pattern. Periodic acid-Schiff stains showed the characteristic diastase-resistant intracytoplasmic crystals. Immunohistochemical studies showed focal myoglobin reactivity in one case, while cytokeratin, vimentin, S100 protein, chromogranin, synaptophysin, neurofilaments, leu-enkephalin, desmin, smooth muscle actin and muscle-specific actin were negative in both cases. The patient with the anterior mediastinal tumour died of disease 14 months after diagnosis, and the patient with the posterior mediastinal mass remained well for at least 15 years and was later lost to follow-up. CONCLUSIONS: As has been observed in other anatomic areas, namely soft tissues, alveolar soft part sarcomas may follow an uncertain natural history. Interestingly, in our cases, the tumour in the anterior mediastinum followed a fatal course raising the possibility that the anatomic location of the tumour may have play a role in the behaviour of the tumour.

Adult↗

Primary malignant 'triton' tumour of the lung.

Two cases of malignant 'triton' tumour arising within lung parenchyma are described. The patients were a three-year-old child and a 53-year-old man. Both patients presented with shortness of breath and a large intrapulmonary mass on chest X-ray. Neither patient had a history of von Recklinhausen's neurofibromatosis. The lesions were treated by pneumonectomy. Grossly, both tumours presented as large, soft and gelatinous intraparenchymatous masses measuring 130 mm and 80 mm, respectively. Histologically, they were characterized by an atypical spindle cell proliferation embedded in an abundant myxoid stroma. Focal areas of rhabdomyoblastic differentiation characterized by large cells with abundant eosinophilic cytoplasm and occasional cytoplasmic cross-striations could be seen admixed with the atypical spindle cell elements. Immunohistochemical studies showed a focal positive reaction for S-100 protein in the atypical spindle cells embedded within the myxoid stroma, and a strong positive reaction for desmin and myoglobin in the rhabdomyoblastic areas. The child died three months after diagnosis with extension of the tumour into the thoracic cavity. The second patient has been lost to follow-up. Although rare, malignant 'triton' tumour should be considered in the differential diagnosis of primary spindle cell sarcomas of the lung.

Child, Preschool↗

Primary mediastinal choriocarcinomas: a clinicopathologic and immunohistochemical study of eight cases.

Primary choriocarcinoma of the anterior mediastinum is by far the rarest and most controversial form of extragonadal germ cell tumor. A clinicopathologic study of eight primary mediastinal neoplasms bearing the histopathologic and immunohistochemical features of choriocarcinoma is presented. The patients were all men between the ages of 21 and 63 years (mean, 42 years). Clinical symptoms included shortness of breath, chest pain, cough, and superior vena cava syndrome; one patient also had gynecomastia. All patients presented with large anterior mediastinal masses on chest radiographs that measured an average of 10 cm in greatest diameter. Grossly, the tumors were described as large, soft, extensively hemorrhagic, and with foci of necrosis. Histologically, they were characterized by a dual cell population composed of cytotrophoblastic cells with uniform, round nuclei, clear cytoplasm, and prominent nucleoli admixed with large, multinucleated syncytiotrophoblastic cells with bizarre nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm. Immunohistochemically, the tumors were notable for strong keratin and beta-human chorionic gonadotropin (HCG) positivity. Seven patients presented at the time of diagnosis with thoracic and extrathoracic (liver, adrenal, kidney, and spleen) metastases. In one case, the tumor was entirely confined to the mediastinum. All patients died over a period of 1 to 2 months. Complete autopsies were performed in all cases; none of the patients showed evidence of a testicular tumor or scar after thorough examination of the testes on serial sectioning. The present cases demonstrate the widespread distribution of germ cells in the human body and lend further support to the existence of primary extragonadal choriocarcinoma arising in the thymic region.

Adrenal Gland Neoplasms↗