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Biomedical subjects

M A Luna

Publications and source records attributed to M A Luna.

At least 91 records · Page 5Linked to original sources
PubMed1990

Fatal pulmonary failure complicating high-dose cytosine arabinoside therapy in acute leukemia.

One hundred three relapsed leukemia patients were treated with high-dose cytosine arabinoside (Ara-C); 3 g/m2 intravenously over 2 hours every 6 to 12 hours for a total of nine to 12 doses or 3 g/m2 intravenously over 2 hours for two doses 12 hours apart followed by a continuous infusion of 1.5 g/m2 over 24 hours daily for 3 to 4 days. Thirteen of them developed adult respiratory distress syndrome (ARDS) without having any recognized reason for the development of pulmonary edema. This problem showed no correlation with age or prior chemotherapy. Four of the patients recovered, but in nine this complication was fatal. The authors have reviewed the clinical course of these 13 patients and the postmortem findings of the seven patients who had an autopsy performed. The pulmonary tissue from six patients showed massive edema and one had diffuse alveolar damage. Histologic examination revealed a highly proteinaceous intraalveolar infiltrate without any inflammatory reaction in all cases. Intestinal tissue from all patients revealed changes compatible with cytotoxic damage, and pleura and/or pericardium from six of the seven patients showed an extensive fibrinous exudate suggestive of capillary leakage. The time sequence of the clinical events and the histologic findings indicate that high-dose Ara-C treatment in leukemia may cause a capillary leakage syndrome with ARDS that may progress to fatal respiratory failure.

Acute Disease↗
PubMed1990

Flow cytometric DNA content of adenoid cystic carcinoma of submandibular gland. Correlation of histologic features and prognosis.

Flow cytometric analysis of nuclear DNA content was performed in 26 adenoid cystic carcinomas of the submandibular gland using archived, paraffin-embedded tissues. The DNA content was compared with multiple histologic parameters and clinical course. Ten carcinomas (38%) were aneuploid and 16 (62%) diploid. Aneuploid carcinomas demonstrated a higher frequency of solid cytoarchitecture, lymph node metastases, and advanced clinical stage, as compared with diploid carcinomas. Other histologic features predicting aggressive clinical behavior also correlated with abnormal DNA content and included invasion of nerves larger than 0.25 mm and intravascular extension. Our data suggest that DNA content analysis can be an effective objective parameter in the clinicopathologic assessment of adenoid cystic carcinoma.

Adolescent↗
PubMed1990

Undifferentiated carcinomas of the major salivary glands.

Undifferentiated salivary carcinomas are defined as primary epithelial malignant neoplasms that are devoid of any phenotypic expression by light microscopy that would allow them to be otherwise classified. A clinicopathologic study of sixteen so-defined carcinomas of the major salivary glands is presented. The carcinomas are unquestionably high-grade malignant neoplasms. Ten of the sixteen patients were dead because of their disease within 4 1/2 years of histologic diagnosis. Cell size and ultrastructural features have little bearing on prognosis. The single most important clinicopathologic factor relating to patient outcome is size of the primary neoplasm. All patients with carcinomas larger than 4 cm died, and these carcinomas had nearly two times the incidence of perineural invasion, extrasalivary extension, and locoregional failure of control.

Aged↗
PubMed1990

DNA flow cytometry of acinic cell carcinomas of major salivary glands.

Fifteen acinic cell carcinomas from an equal number of patients were analysed for their DNA content and proliferative (S-phase) index by flow cytometry from archival tissues. Seven of the carcinomas manifested a diploid DNA content. None of the patients with diploid acinic cell carcinomas died of their carcinomas and none developed metastases in follow-up periods extending for 10 or more years. Four of eight patients with aneuploid acinic cell carcinomas have died because of their malignancies within a 10 year period after the first surgical removal of the carcinoma. Five of the eight patients exhibited metastases. Although the number of cases does not permit strong correlations between histopathological features, abnormalities in DNA content and outcome of patients, it was noted that carcinomas with prominent necrosis, tubuloductal differentiation and 'dedifferentiated' areas displayed more aggressive biological courses.

Adolescent↗
PubMed1990

Myofibroblastoma of the tongue. An immunohistochemical, ultrastructural, and flow cytometric study.

A case of myofibroblastoma arising in the tongue of a 77-year-old man is described. The patient presented with a submucosal tongue mass without other associated symptoms. The tumor was 2 cm in diameter, well circumscribed, and composed of uniform spindle cells arranged in fascicles. Electron microscopic examination and immunohistochemistry demonstrated a myofibroblastic origin for the tumor cells. DNA flow cytometric analysis showed a diploid DNA content of this tumor. To the authors' knowledge, this is the first report of myofibroblastoma occurring in the tongue.

Actins↗
PubMed1990

Histopathologic grading of salivary gland neoplasms: I. Mucoepidermoid carcinomas.

Histopathologic grading of salivary gland neoplasms has been done with various degrees of success and hence various degrees of acceptance among pathologists and otolaryngologists-head and neck surgeons. Given their histopathologic diversity, three carcinomas--mucoepidermoid, adenoid cystic, and acinic cell--would seem to be suitable candidates for grading. In this, the first of a three-part series, the authors present a three-level grading scheme for mucoepidermoid carcinomas. It combines histocytologic and growth features of the carcinomas that independently or together, in other grading proposals, have shown prognostic value.

Carcinoma↗
PubMed1990

Histopathologic grading of salivary gland neoplasms: II. Acinic cell carcinomas.

Acinic cell carcinomas display varied cytoarchitectural patterns of growth that should allow for formulation of histopathologic grading. Grading of these carcinomas may serve to identify subsets whose biologic behavior is more aggressive than the usually accepted low-grade behavior of acinic cell carcinomas as a group. To that end, a three-level histopathologic grading scheme is presented.

Carcinoma↗
PubMed1990

Histopathologic grading of salivary gland neoplasms: III. Adenoid cystic carcinomas.

Histopathologic grading of adenoid cystic carcinomas can provide valuable prognostic information, particularly when the presence or absence of a solid growth architecture is noted. Other growth patterns, exemplified by a tubuloductal or cribriform-cylindromatous differentiation, are associated with a more protracted biologic course and less rapid mortality. A three-tiered grading system based on the three growth patterns of the carcinoma is presented.

Carcinoma, Adenoid Cystic↗
PubMed1989

Renal cell carcinoma metastatic to the thyroid.

Metastatic renal cell carcinoma to the thyroid is an uncommon occurrence that can cause clinical and pathologic problems in diagnosis. The authors report seven cases from the files of The University of Texas M.D. Anderson Cancer Center, Houston, Texas. Each presented clinically as a palpable thyroid nodule months or years after the primary renal cell carcinoma had been resected. Although renal cell carcinoma is more common in men, we found a female predominance of 6:1 in this series. These lesions appear as solitary "cold" nodules on iodine 131 scans and may be misdiagnosed as primary thyroid neoplasms, especially if the renal primary is still unrecognized. A correct diagnosis is important because surgical management can be curative. The diagnosis is facilitated by the use of fat stains, electron microscopic study, and immunoperoxidase stains.

Aged↗
PubMed1989

Primary osteosarcoma of the parotid gland.

Four cases of primary osteosarcoma of the parotid gland, where these tumors rarely occur, are presented. This neoplasm may arise after radiation therapy, but the majority arise de novo. As a group, extraosseous osteogenic sarcomas are aggressive and lethal. Patients with these tumors have an average 5-year survival rate of 15.6%. Of the four patients reported on two died within 6 months to 3 years, one has lung metastases, and one has been lost to follow-up.

Aged↗
PubMed1989

Pulmonary dirofilariasis: the great imitator of primary or metastatic lung tumor. A clinicopathologic analysis of seven cases and a review of the literature.

The clinical, radiologic, and pathologic features of seven patients with pulmonary dirofilariasis were studied. The findings were analyzed in conjunction with those of 76 cases previously reported from the United States. We found that, in most instances, the disease was acquired in states along the Atlantic and Gulf coasts and occurred predominantly in whites (94.7%) in their fifth or sixth decades of life, with a male to female ratio of 2:1. Symptoms, commonly chest pain, cough, or hemoptysis, were present in 37.6% of patients. Most patients (62.4%) were asymptomatic, and the disease was discovered incidentally on routine radiography or during the investigation of another problem. Peripheral eosinophilia was present in 20% of patients. The radiologic findings consisted of single (89.8%) or multiple (10.2%) pulmonary nodules that simulated primary or metastatic lung tumor. Dirofilariasis was not included in the clinical differential diagnosis in any of the patients. In one case, the diagnosis was accurately obtained by fine needle aspiration biopsy. All other patients required thoracotomy with excisional lung biopsy for diagnosis. Pathologically, the dirofilaria nodule consisted of a spherical subpleural infarct with a central thrombosed artery containing Dirofilaria immitis in various stages of disintegration.

Adult↗
PubMed1989

Carcinomas ex monomorphic adenoma of salivary glands.

A clinicopathological analysis of eight examples of carcinomas arising from salivary gland monomorphic adenomas, carcinomas ex monomorphic adenoma, is presented. These uncommon to rare neoplasms have a predilection for the parotid glands, are diagnosed about a decade later than their benign precursors, and most often arise from the dermal analogue type of monomorphic adenoma. As judged by follow-up periods of two to 16 years, carcinomas ex monomorphic adenoma are locally aggressive neoplasms with the clinical course marred by recurrences but without regional or distant metastases.

Adenocarcinoma↗
PubMed1989

Histogenesis of salivary gland neoplasms: a postulate with prognostic implications.

In a continually renewing cell population, stem cells can be regarded as a reservoir of cells with a high capacity for self renewal that give rise to all differentiated progeny. They are the primary source for the generation and maintenance of cellular diversity and tissue homeostasis. In general, neoplasms manifest differentiation pathways similar to those found in the development and renewal of the normal tissues from which they arise. This feature serves as a basis for classification schemes of neoplasms and, as in the normal tissues, there is usually an inverse correlation between proliferative capacity and differentiation within the neoplasms. In our postulate of the histogenesis of salivary gland neoplasia, we evoke the stem cell model to account for the considerable phenotypic heterogeneity seen with these neoplasms. We further consider the neoplasms and, in particular, their myoepithelial constituencies to be manifestations of escape from normal regulatory mechanisms that determine differentiation pathways which a stem cell and its progeny can take. Clinical and basic scientific evidence are presented to support the postulate and also to point to the mitigating role that myoepithelial differentiation has in the biological course of salivary gland neoplasms.

Cell Differentiation↗
PubMed1989

DNA content and proliferative activity of myoepitheliomas.

This report adds 16 myoepitheliomas of salivary glands to the 47 already recorded in the literature. It includes, for the first time, a flow cytometric analysis of their ploidy (DNA content) and proliferative capacity (S-phase fraction). Thirteen myoepitheliomas were diploid; three were aneuploid in their DNA content. A high proliferative capacity was always associated with an abnormal DNA content. Only one diploid myoepithelioma had a high S-phase fraction. Both flow-cytometric parameters are good predictors of an aggressive biological behaviour. Recurrences, however, were all the outcome of incomplete primary removal of the myoepitheliomas. Four of the twelve (33 per cent) diploid myoepitheliomas recurred and one, with high S-phase fraction, led to the death of the patient. Two of the three (67 per cent) aneuploid myoepitheliomas recurred. Extensive loco-regional invasion by one killed the patient. The other has clinical evidence of distant metastasis.

Adolescent↗
PubMed1989

Necrotizing gas-forming infections in cancer patients.

Necrotizing gas-forming infections in cancer patients present some unique characteristics, such as nontraumatic, spontaneous clostridial gangrene and gangrene involving an ischemic tumor mass. These infections can be rapidly progressive and uniformly fatal without surgical debridement. We review ten cases of gas gangrene seen during an 18-year period. Four were caused by Clostridium species and six by other organisms. Neutropenia was present in seven patients. During the last nine years, Clostridium septicemia occurred in 54 patients; in only two of those patients did gas gangrene ensue.

Adolescent↗
PubMed1989

Low-grade and high-grade adenocarcinomas of the salivary duct system.

Adenocarcinomas of salivary glands are encountered less frequently than adenoid cystic or mucoepidermoid carcinomas. They fall into two well-defined clinicopathologic groups: 1) those arising from intercalated ducts and 2) those from the excretory and interlobular ducts. The former, designated terminal duct adenocarcinomas, are low-grade malignancies found preponderantly in the oral cavity, especially the palate. The latter, designated salivary duct carcinomas, are high-grade neoplasms and arise almost exclusively in major salivary glands, especially the parotid gland.

Adenocarcinoma↗
PubMed1989

Spectrum of pathologic manifestations of Pneumocystis carinii pneumonia in patients with neoplastic diseases.

Pneumocystis carinii is the most common protozoan organism causing infection in immunosuppressed patients. This study, based on a review of 32 lung biopsies and 13 autopsies of patients with neoplastic diseases who developed P carinii pneumonia, emphasizes the morphologic variation of this disease. Excluded from this study are those patients with PCP secondary to bone marrow transplantation and AIDS. P carinii pneumonia occurred predominately in patients with malignant lymphoreticular neoplasms, 73% of those in our series, and the remaining 27% had solid tumors. There were 27 males and 18 females and their ages ranged from 1 to 73 years, with a median age of 30 years. Microscopically, the diagnostic intraalveolar foamy exudate of P carinii pneumonia was present in only 58% of the cases. Furthermore, diffuse alveolar damage alone was present in 26% of cases. This change was especially prominent when the characteristic foamy material was scanty. Other tissue reactions to P carinii included the presence of giant cells, epithelioid granulomas, desquamative interstitial-like pneumonitis, and interstitial lymphoid infiltrate. Extrapulmonary dissemination was not observed in this patient population. The pathologist should be aware of the marked variations that occur in the morphologic appearance of PCP, and the diagnosis of Pneumocystis infection should not be discarded until a careful search for the organisms using silver stains is rendered negative.

Adolescent↗