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M N Koss

Publications and source records attributed to M N Koss.

At least 73 records · Page 4Linked to original sources
PubMed1994

Primary adenoid cystic carcinoma of the lung. A clinicopathologic and immunohistochemical study of 16 cases.

BACKGROUND: Adenoid cystic carcinoma (ACC) is a rare but distinctive salivary gland-type malignant neoplasm that arises infrequently as a primary tumor in the lung. METHODS: The clinical and pathologic features in 16 cases of primary ACC of the lung were reviewed, and immunohistochemical stains on paraffin sections were performed in 7 cases. RESULTS: The patients' ages ranged from 29 to 79 years (mean age, 54 years); 11 were men and 5 were women. Clinically, most patients were seen initially with obstructive symptoms, including cough, wheezing, shortness of breath, and hemoptysis. Eight tumors were in the left lung and eight in the right lung. The lesions were treated by pneumonectomy in seven patients, lobectomy in six, and lobectomy plus chemotherapy in two. One patient was treated with chemotherapy alone after undergoing a diagnostic biopsy that revealed advanced disease. Grossly, most lesions were described as endobronchial and measured from 0.9 to 4.0 cm in greatest dimension; two cases, however, showed poorly circumscribed infiltrative tumors. Histologically, three main growth patterns were identified admixed in various proportions: cribriform (cylindromatous), tubular, and solid. Immunohistochemical study in six of seven cases showed a prominent myoepithelial cell component, as evidenced by immunoreactivity for keratin, actin, and S-100 protein in numerous tumor cells. Clinical follow-up ranging from 2 to 15 years in six patients showed that three were alive and well without evidence of recurrence or metastases at 5, 10, and 12 years, respectively, and three were alive with recurrence at 2, 5, and 15 years, respectively. Three other patients died of unrelated conditions at 2, 7, and 9 years, respectively, after diagnosis. Two patients in the study were seen initially with metastatic spread at the time of initial diagnosis and died 2 months and 1 year later with widespread metastases to lymph nodes, liver, spleen, kidney, and bone despite intensive chemotherapy. CONCLUSIONS: Disease stage at the time of diagnosis may play an important role in predicting the clinical outcome of patients with these tumors. Despite their generally slow and indolent growth in other locations, ACC arising in the lung may in certain cases be more aggressive.

Adult↗
PubMed1994

The spectrum of pathological changes in the lung in children with the acquired immunodeficiency syndrome: an autopsy study of 36 cases.

We present the pulmonary findings in 36 autopsies of children affected by the acquired immunodeficiency syndrome (AIDS). Twenty-three patients were male and 13 were female, ranging in age between 3 days and 13 years. Twenty children had human immunodeficiency virus (HIV)-positive parents or parents who were at high risk of exposure (intravenous drug abusers and prostitutes), five had a history of transfusion, and one had a history of renal transplantation and blood transfusion. Clinically, the patients presented with recurrent infections, failure to thrive, hepatosplenomegaly, fever, cough, and/or hemoptysis. Histologically, specific infectious processes were the most common finding (75% of cases), with Pneumocystis carinii pneumonia being the most prevalent type of infection, followed by bacterial pneumonia. Neoplastic conditions and lymphoid interstitial pneumonia were less frequent (approximately 10% of cases). In addition, in approximately 10% of the cases the pulmonary findings were non-specific (ie, pulmonary edema and atelectasis) and probably unrelated to HIV infection. Our findings suggest that specific infectious conditions constitute the most common type of pulmonary pathology in children with AIDS. However, because there is a small percentage of children with nonspecific findings, a transbronchial biopsy is important for proper evaluation before institution of therapy.

AIDS-Related Opportunistic Infections↗
PubMed1994

Rhabdomyosarcomas of the anterior mediastinum: report of four cases unassociated with germ cell, teratomatous, or thymic carcinomatous components.

Four cases are presented of primary anterior mediastinal tumors in young adults that were characterized by solid, infiltrative lesions showing histologic and immunohistochemical features of rhabdomyoblastic differentiation. The patients were three men and one woman between 19 and 27 years of age (mean age, 23 years). All patients presented with symptoms referable to their tumors, including cough, chest pain, dyspnea, and left-sided pleural effusion. Grossly and radiographically, the lesions were characterized by their solid, infiltrative appearance. Histologically, two cases corresponded to the solid variant of alveolar rhabdomyosarcoma, one case was an embryonal rhabdomyosarcoma with a predominant spindle cell component, and the remaining case showed the features of a pleomorphic rhabdomyosarcoma. No glandular, epithelial, or other component could be identified in any of the tumors on extensive sampling. Immunohistochemical studies showed positive staining of the tumor cells with actin, desmin, and vimentin antibodies, with focal positivity for myoglobin in three cases and focal positive staining with S-100 protein in one case. Stains for low and high molecular weight keratin, carcinoembryonic antigen, alpha-fetoprotein, human chorionic gonadotropin, placental alkaline phosphatase, leukocyte-common antigen, and neuron-specific enolase were negative. All patients experienced rapid recurrence and metastases within the first 6 months after diagnosis. Three patients died within this period due to their tumors; the fourth patient has been lost to follow-up. Pure primary rhabdomyosarcomas of the anterior mediastinum are highly aggressive neoplasms that should be distinguished from germ cell, teratomatous, or carcinosarcomatous tumors with a focal rhabdomyoblastic component.

Adult↗
PubMed1994

Plasma cell-rich thymoma.

A thymoma in the anterior mediastinum of a 49-year-old woman was histologically remarkable for the presence of a prominent plasma cell stromal component surrounding the neoplastic epithelial elements. Polyclonal immunoreactivity for kappa and lambda light chains was obtained by immunocytochemical staining of the plasma cells in the stroma. Although no evidence of myasthenia gravis or other type of autoimmune process could be demonstrated at the time of initial diagnosis, a polyclonal hypergammaglobulinemia of unknown cause subsequently developed in the patient. This case may represent an extreme example of aberrant immunologic modulation of the thymus to an autoimmune process with massive hyperplasia of the B-cell compartment of the gland.

Female↗
PubMed1994

The spectrum of immunohistochemical staining of small-cell lung carcinoma in specimens from transbronchial and open-lung biopsies.

Immunohistochemistry is increasingly used as an aid in the diagnosis of small-cell lung carcinoma (SCLC). Previous studies have investigated immunohistochemical staining of SCLC with small numbers of antibodies, but few have examined large series with a broad panel of antibodies. For this reason, the authors examined the distribution and intensity of staining of 20 open-lung biopsy (OLB) and 21 transbronchial biopsy (TBB) specimens of SCLC with a panel of epithelial, neuroendocrine, and hormonal markers. Small-cell lung carcinoma stained most frequently with epithelial markers, followed by neuroendocrine and hormonal markers. Similar percentages of OLB and TBB specimens stained for keratin (100% each) and epithelial membrane antigen (100% and 95%, respectively). Unexpectedly, BER-EP4 stained 100% of OLB specimens. Chromogranin A was the most frequent neuroendocrine marker in OLB and TBB specimens (60% and 47%, respectively) followed by neuron-specific enolase (60% and 33%), Leu-7 (40% and 24%), and synaptophysin (5% and 19%). No neuroendocrine immunohistochemical reactivity was found in 24% of TBB specimens and 20% of OLB specimens. Bombesin was the most sensitive hormonal marker (45% of OLB specimens). These results show that keratin, epithelial membrane antigen, and BER-EP4 are reliable epithelial markers for SCLC in both TBB and OLB specimens. In addition, negative staining for neuroendocrine markers, because it can occur in as many as 25% of cases, should not deter the diagnosis of SCLC.

Biomarkers↗
PubMed1994

Epithelioid hemangioendothelioma of the anterior mediastinum. Clinicopathologic, immunohistochemical, and ultrastructural analysis of 12 cases.

Twelve cases are reported of primary epithelioid hemangioendothelioma of the anterior mediastinum. Patient ages ranged from 19 to 62 years (mean, 49.4); three were women and nine were men. Seven patients presented with symptoms due to compression of surrounding structures; the remainder were asymptomatic and the lesions were discovered on routine chest x-ray films. The tumors measured from 4.5 to 13.5 cm in greatest diameter; they were encapsulated and well-circumscribed in seven cases and locally infiltrative in five. Histologically, a spectrum of features was observed ranging from those classically described for low-grade epithelioid hemangioendothelioma at other locations--including cells with abundant eosinophilic cytoplasm showing prominent vacuolization and intracellular lumen formation, few mitotic figures, and myxoid changes in the stroma--to more pronounced cytologic atypia, increased mitotic activity, and areas of necrosis. Metaplastic bone formation and osteoclast-type giant cells were observed in five cases, and four tumors displayed focally a prominent intravascular papillary endothelial component. Immunohistochemical studies showed positive staining of the neoplastic cells with factor VIII-related antigen and vimentin and focal staining in most cases with Ulex europaeus lectin. Stains for broad-spectrum keratin, CAM-5.2, S-100 protein, CD34, actin, and desmin were negative. Electron microscopic examination in three cases showed features distinctive for epithelioid vascular endothelial cells, including abundant cytoplasmic intermediate filaments, basal lamina material, marked pinocytotic activity, and primitive intracytoplasmic lumen formation. All cases were treated by surgical excision. Follow-up information was available in nine patients; seven patients were alive and well without evidence of disease 2-21 years after diagnosis (mean follow-up, 8 years); one patient had a recurrence after 1 year and died due to complications of surgery, and another patient died after 1 year of undetermined causes. Despite their often ominous clinical, radiological, and pathological features, epithelioid hemangioendotheliomas arising in the anterior mediastinum appear to behave as low-grade malignant neoplasms that may be adequately controlled in most instances by surgery alone.

Adult↗
PubMed1994

Sclerosing hemangioma of the lung. Granulomatous variant.

We present a case of granulomatous sclerosing hemangioma of the lung in a 43-year-old white woman in whom a pulmonary nodule was found on a routine chest roentgenogram. Surgical resection of a well-circumscribed pulmonary nodule was performed. Histologically, the tumor showed the typical features of sclerosing hemangioma with the unusual feature of a florid granulomatous reaction. Immunohistochemical studies using antibodies for epithelial membrane antigen decorated the tumoral cells, while factor VIII was positive in the vascular structure. Histochemical stains for microorganisms yielded negative results.

Adult↗
PubMed1994

Endobronchial lipomas: a clinicopathologic study of four cases.

Four cases of endobronchial lipomas are presented. The patients were men between 45 and 54 yr of age. Clinically, two of the patients presented with cough and one with shortness of breath. Two lesions were located in the left lower lobe, one in the right upper lobe, and one in the right lower lobe. Because of the clinical suspicion of malignancy, all patients underwent radical surgical procedures; lobectomy was performed in 3 patients, and pneumonectomy in one. Grossly, all the lesions were characterized by well-circumscribed, soft, yellow nodules that ranged in size from 1.2 to 3.0 cm in greatest diameter. Histologically, the tumors resembled lipomas in other locations, i.e., they were composed of mature adipose tissue devoid of atypia. In two cases, prominent spindle cell areas were also present similar to those of spindle cell lipoma. Identification of the lesion by endoscopic and radiologic means may help avoid unnecessary radical surgery. A review of the literature on these unusual lesions is presented along with a discussion of their differential diagnosis.

Bronchial Neoplasms↗
PubMed1994

Pulmonary lymphangioleiomyomatosis. Diagnosis based on results of transbronchial biopsy and immunohistochemical studies and correlation with high-resolution computed tomography findings.

The diagnosis of lymphangioleiomyomatosis was established in a 35-year-old woman with hemoptysis, mild cough, and dyspnea based on histologic review of results of a transbronchial biopsy correlated with high-resolution computed tomographic scan findings. A chest x-ray film revealed diffuse interstitial lung disease, and a high-resolution computed tomographic scan showed diffuse cystic changes throughout both lungs. The transbronchial biopsy specimen revealed cystic changes and a patchy, sometimes nodular proliferation of smooth muscle that focally expanded the interstitium suggestive of lymphangioleiomyomatosis. The smooth-muscle nature of the cells was confirmed by positive immunohistochemical stains for actin and desmin; positive staining for HMB-45 was also observed. Although the diagnosis of lymphangioleiomyomatosis usually requires an open lung biopsy, this case shows that rarely, in the appropriate clinical setting, the diagnosis may be rendered based on results of a transbronchial biopsy in conjunction with findings from ancillary immunohistochemical studies and high-resolution computed tomography.

Adult↗
PubMed1994

Thymofibrolipoma. A histologic variant of thymolipoma.

We report two cases of a thymic neoplasm showing abundant fibroconnective tissue with focal areas of fatty tissue. The two patients, a 9-year-old girl and a 32-year-old man, were found to have an anterior mediastinal mass on routine chest roentgenograms. Surgical resection was performed in both cases. Because of the histologic features shown by these neoplasms, we believe that these cases represent a variant of thymolipoma, and we have named it thymofibrolipoma.

Adult↗
PubMed1993

Mediastinal paragangliomas. A clinicopathologic and immunohistochemical study of 16 cases.

BACKGROUND: Paragangliomas of the mediastinum are rare neoplasms. Because of their rarity, the spectrum of morphologic and immunohistochemical features and biologic behavior of these tumors in this location has not been delineated. METHODS: A retrospective study of 16 cases of mediastinal paragangliomas was undertaken to evaluate their clinicopathologic and immunohistochemical features. RESULTS: The patients were 10 men and 6 women whose ages ranged from 16-69 years of age (mean, 42.5 years). Twelve tumors were located in the posterior mediastinum, and three tumors were located in the anterior mediastinum. In one case, the exact location of the tumor within the mediastinum was not available. Microscopically, the nesting pattern (zellballen) was the most commonly encountered. Areas of stromal hyalinization were also frequent and were marked in two tumors. In two cases there was a prominent spindle cell component, and two cases showed granular cell changes in the cytoplasm of the tumor cells. Cellular pleomorphism was observed in the majority of cases. Occasional mitoses were seen in a few cases. Immunohistochemical studies in 10 cases showed chromogranin reactivity in 10 of 10 cases, S-100 protein in 9 of 10 cases, leu-enkephalin in 6 of 10 cases, and neurofilament protein in 5 of 10 cases. Keratin was negative in all cases studied. All patients underwent surgical resection of their tumors, and one patient underwent adjuvant radiation therapy. Follow-up information ranging from 1-168 months (mean, 84.5 months) was obtained in 12 patients. Nine patients (75%) were alive and well at last follow-up. In one patient the tumor metastasized to spinal space and bone marrow, and another patient died with metastases to lymph node, lung, and pelvis 14 years after initial diagnosis. CONCLUSIONS: The only parameter found to correlate with aggressive behavior was the extent of circumscription and/or local infiltration of the tumor at initial resection. No clinical, histologic, or immunohistochemical features were otherwise found to separate aggressive from indolent clinical behavior. Regular follow-up is recommended in these patients due to the potential for these tumors to metastasize.

Adolescent↗
PubMed1993

Rhabdomyomatous thymoma.

A case of a thymic neoplasm with a prominent rhabdomyomatous component is presented. The patient, a 21-year-old asymptomatic man, had an anterior mediastinal mass found on routine chest radiographs. Surgical resection of an encapsulated anterior mediastinal mass was performed. Histologically, two distinct cell populations were apparent, one epithelial and the other myoid. Immunohistochemical studies using antibodies for keratin decorated the epithelial component of this lesion; antibodies for myoglobin and desmin strongly stained the myoid component.

Adult↗
PubMed1993

Pigmented pulmonary carcinoid tumor. An immunohistochemical and ultrastructural study.

We evaluated three cases of pigmented pulmonary carcinoid tumors that were retrieved from the files of the Armed Forces Institute of Pathology, Washington, DC. Clinical follow-up showed no indication of tumor recurrence or metastases, nor was there evidence of malignant melanoma. All three cases exhibited histologic features of typical carcinoid tumor; there were focal oncocytic changes in two cases. Finely dispersed, brown pigment, believed to be melanin, was distributed in two different patterns: in sustentacular cells (case 1) or within the tumor cells (cases 2 and 3). Fontana-Masson stain was positive in areas of this pigment in all cases. The tumor cells showed immunoreactivity for chromogranin, synaptophysin, keratin (AE1/AE3 and CAM-5.2), and S100 protein in all cases. Focal staining for vimentin and corticotropin was seen within neoplastic cells in two cases. The pigmented sustentacular cells in case 1 showed focal immunoreactivity for S100 protein and HMB-45. Ultrastructural studies of paraffin-embedded tissues were performed in two cases. They showed well-developed melanosomes in the pigmented sustentacular cells in case 1. In both cases, cytoplasmic neurosecretory-type granules were identified in neoplastic cells. These findings demonstrate that pigmented pulmonary carcinoid tumor has an immunohistochemical profile similar to that of typical pulmonary carcinoid tumor. In some instances, pigmented pulmonary carcinoid tumors may show ultrastructural evidence of melanocytic and neuroendocrine differentiation. These immunohistologic and ultrastructural findings distinguish pigmented pulmonary carcinoid tumor from malignant melanoma and support the concept of "multidirectional cellular differentiation."

Adult↗
PubMed1993

Metastatic mature teratoma in lung following testicular embryonal carcinoma and teratocarcinoma.

We report seven cases of metastatic mature teratoma in the lung from testicular teratocarcinoma and embryonal carcinoma. The patients were between 19 and 58 years of age when orchiectomy was performed. The primary tumors each contained a prominent component of embryonal carcinoma as well as mature and immature teratoma in six patients and only embryonal carcinoma in one. In three patients metastatic pulmonary nodules were detected at the time of orchiectomy, and in three others pulmonary metastases occurred 4 and 8 months after orchiectomy. In one patient the interval was 1.5 years; however, chest roentgenography was not performed during that period. All the patients received chemotherapy or radiation therapy prior to removal of the pulmonary metastases. Thoracotomy was performed between 4 months and 9 years after detection of pulmonary metastases on chest roentgenograms. In one patient the procedure consisted of a lobectomy and in another a pneumonectomy. In the remaining five cases excision of the nodules was performed. The pulmonary metastases resected were grossly solitary lesions in five patients and multifocal in two. Microscopically, each tumor consisted entirely of mature teratoma. Cuboidal and mucin-secreting glandular epithelium predominated in the cystic areas; fibroconnective tissue was the predominant feature of the solid areas. In four patients the course has been indolent with no manifestations of the disease after at least 1 year; in two patients no follow-up was obtained; and one patient died, apparently of a septic process. We present a discussion of this interesting and unusual event.

Adult↗
PubMed1992

Thymomas presenting as pleural tumors. Report of eight cases.

Eight cases of thymomas presenting as pleural-based lesions are presented. The patients are five men and three women between the ages of 38 and 71 years (mean 54.5). Histologically, six tumors showed morphologic features indistinguishable from classical mediastinal thymomas, namely lobulation produced by fibrous bands and a biphasic cell population composed of epithelial cells admixed with small lymphocytes. One case showed prominent spindle cell configuration and marked vascularization resulting in a hemangiopericytomalike appearance; in another case, the epithelial component was associated with cystic structures. The radiographic findings were diffuse pleural thickening with encasement of the lung in four cases; an ill defined mass involving the right diaphragmatic pleura with engulfment of the left lower lobe in one case; diffuse pleural thickening along the mid lateral axillary line in one case; and left-sided pleural masses involving the diaphragmatic and chest wall pleural surfaces in another. In the remaining case, a massive unilateral left pleural effusion obscured the underlying lesion. Clinically, the patients presented with varied symptoms, including shortness of breath, fever, and weight loss. Follow-up information was obtained in four patients. One patient died 1 month after initial diagnosis, but no details of the cause of death were available. Another had metastasis to the groin 1 year after diagnosis. The other two patients were alive and well 2-10 years after the initial diagnosis.

Adult↗
PubMed1992

Acinic cell carcinoma of the lung ("Fechner tumor"). A clinicopathologic, immunohistochemical, and ultrastructural study of five cases.

The clinical, pathological, immunohistochemical, and ultrastructural features in five cases of primary acinic cell carcinoma of the lung are presented. The patients' ages ranged from 44 to 75 years (mean, 56); four were women and one a man. The lesions were discovered incidentally on routine chest x-ray and ranged from 1.2 to 4 cm in greatest diameter. Three tumors were located in the right middle lobe, one in the right upper lobe, and one in the left upper lobe. In three cases, the lesions presented as asymptomatic subpleural nodules in proximity to secondary bronchi, one case presented as an endobronchial tumor that led to obstructive symptoms, and one case as a well-circumscribed deep parenchymal nodule. Histologically, the tumors were composed of clear cells with abundant granular cytoplasm growing as solid sheets with focal acinar, microcystic, and papillocystic areas. Immunohistochemical stains showed strong positivity of the tumor cells for low-molecular-weight cytokeratins and epithelial membrane antigen (EMA). Focal weak cytoplasmic positivity was observed in three cases with alpha-1-antichymotrypsin and in one case with amylase. Stains for vimentin, S-100 protein, chromogranin, and lysozyme were negative in all cases examined. Electron microscopy performed in four cases showed abundant zymogen-type cytoplasmic granules of variable electron density characteristic of acinar-type secretory cells. All patients were treated by lobectomy alone. Follow-up of 3 to 10 years in four cases revealed that all patients were alive and well, with no evidence of recurrence or metastases. Because of their relatively indolent behavior and favorable prognosis, primary acinic cell carcinoma of the lung must be distinguished from other primary and metastatic clear cell tumors of the lung.

Adult↗
PubMed1992

Lymphoid interstitial pneumonia not associated with HIV infection: role of Epstein-Barr virus.

The polymerase chain reaction (PCR) method was used to determine the presence of Epstein-Barr virus sequences in seven cases of pulmonary lymphoid interstitial pneumonia not associated with HIV infection. Evidence of Epstein-Barr virus genome was found in three of six cases in which beta-globin gene, used as an internal control for the integrity and amplifiability of the tissue DNA, could be detected. These results suggest that Epstein-Barr virus infection is not always required for the development of lymphoid interstitial pneumonia.

Adult↗