Search PubMed⌕ Search

Biomedical subjects

M A Luna

Publications and source records attributed to M A Luna.

At least 19 recordsLinked to original sources
PubMed2004

Carcinomas arising in multilocular thymic cysts of the neck: a clinicopathological study of three cases.

AIMS: To report three cases of primary carcinoma of the neck arising in multilocular thymic cysts (MTC). METHODS AND RESULTS: The patients were three men aged 47, 50 and 52 years who presented with a painless neck mass of several weeks' duration. The patients had no history of previous surgical procedures or of malignancy elsewhere. The tumours in all three patients were located on the right lateral side of the neck; all patients underwent complete surgical resection of the mass. Grossly, the tumours were cystic and measured between 20 and 30 mm in greatest diameter. Histologically, the tumours showed cyst walls lined by squamous epithelium. The cyst walls contained prominent germinal centres with lymphoid hyperplasia, cholesterol cleft granulomas, and scattered keratinized structures reminiscent of Hassall's corpuscles. In addition, a neoplastic cellular proliferation composed of round to oval cells arranged in sheets and originating from the lining of the cystic structures was present. The neoplastic cells showed moderate amounts of eosinophilic cytoplasm, round nuclei, and, in some areas, prominent nucleoli. Mitotic figures were easily found, and cellular pleomorphism was present in several areas. In two cases the tumours showed features of basaloid carcinoma of the thymus, while in one case the pattern was that of squamous cell carcinoma. Immunohistochemical studies for keratin showed a strong positive reaction in the tumour cells, while leucocyte common antigen strongly stained the lymphoid background. Follow-up information obtained in two patients showed them to be alive 6 months after initial diagnosis. One patient was lost to follow-up. CONCLUSION: The cases described here represent an unusual variant of carcinoma arising in multilocular thymic cyst in the neck region.

Adenocarcinoma↗
PubMed2003

Sinonasal tract seromucous adenocarcinomas: a report of 12 cases.

Sinonasal seromucous adenocarcinomas may originate from the surface epithelium or from the submucosal glands. We reviewed the clinicopathologic material from 12 patients with sinonasal tract seromucous adenocarcinomas at the University of Texas M. D. Anderson Cancer Center (Houston, TX). There were nine men and three women age 30 to 87 years (mean age, 56.3 years). The clinical presentation included nasal obstruction, nasal mass, and epistaxis. Eight tumors were located in the nasal cavity, three in the ethmoidal sinuses, and one involved the nasal cavity and ethmoid. Histologically, in nine cases the neoplastic glands were lined by a single cell type, arranged back to back without intervening stroma and often inducing desmoplastic reaction. The remaining three tumors also had a cribriform and papillary pattern. All patients were treated by surgical resection. Three patients had recurrences, which occurred at 36, 36, and 48 months after initial therapy. Their treatment involved surgery and irradiation. Eleven patients are alive and free of disease at 36 to 108 months after diagnosis. One patient died 48 months after diagnosis of another cause. Sinonasal tract seromucous adenocarcinomas arise purely from submucosal seromucous glands. The diagnosis is facilitated by their anatomic location, the absence of tumor within the mucosal surface epithelium, and the striking similarity to terminal tubules of the seromucous glands.

Adenocarcinoma, Mucinous↗
PubMed2001

Genetic heterogeneity in saliva from patients with oral squamous carcinomas: implications in molecular diagnosis and screening.

We performed microsatellite analysis at chromosomal regions frequently altered in head and neck squamous carcinoma on matched saliva and tumor samples from 37 patients who had oral squamous carcinoma. The results were correlated with the cytologic findings and traditional clinicopathologic factors to assess the diagnostic and biological potential of these markers. Our data showed that 18 (49%) of the saliva samples and 32 (86%) of the tumors had loss of heterozygosity (LOH) in at least one of the 25 markers studied. In saliva, the combination of markers D3S1234, D9S156, and D17S799 identified 13 (72.2%) of the 18 patients with LOH in saliva (P < 0.001). For tumors, markers D3S1234, D8S254, and D9S171 together identified 27 (84.3%) of the 32 tumors with LOH at any of the loci tested (P < 0.001). Eleven (55%) of the 20 saliva samples with cytologic atypia and seven (35%) of the 17 specimens without atypia had LOH. Significant correlation between LOH in tumor at certain markers and smoking and alcohol use was found. Our results indicate that: 1) epithelial cells in saliva from patients with head and neck squamous tumorigenesis provide suitable material for genetic analysis; 2) combined application of certain markers improves the detection of genetic alteration in these patients; 3) clonal heterogeneity between saliva and matching tumor supports genetic instability of the mucosal field in some of these patients; and 4) LOH at certain chromosomal loci appears to be associated with smoking and alcohol consumption.

Alcohol Drinking↗
PubMed2001

p73 gene alterations and expression in primary oral and laryngeal squamous carcinomas.

p73, a recently identified gene, maps to chromosome region 1p36.3, which is frequently deleted in a variety of solid tumors. Although the gene shares sequence and functional homologies with p53, its suppressor function has not been proven. We investigated for the first time the genetic and expression status of the p73 gene and analyzed its flanking microsatellite loci on chromosome 1p36.3 in 67 primary oral and laryngeal squamous cell carcinomas to determine their association with these tumors. Our results reveal two missense mutations at codons 469 and 477 and a silent mutation at codon 349 in the C-terminal domain. Site-directed mutagenesis of p73 cDNA with these mutations and a p21 transactivation assay failed to show any significant functional consequences of these mutations. Microsatellite analysis of the flanking loci of p73 in region 1p36 showed overall alterations (loss of heterozygosity and instability) frequency of 39%, 16% at the proximal marker and 46% at the distal markers. Of the 21 cases for which we did protein expression analyses, 11 tumors had a >2-fold variation compared with matching histologically normal mucosa. Our study shows that: (i) intragenic alterations in this gene are rare and lack functional significance; (ii) its variable expression argues against a tumor suppressor function; (iii) this gene plays a minor role in head and neck squamous carcinoma; (iv) a distal site to this gene on 1p36 may harbor another suppressor gene.

Adult↗
PubMed2001

Molecular and biomarker analyses of salivary duct carcinomas: comparison with mammary duct carcinoma.

Salivary duct carcinoma (SDC) is a rare high-grade aggressive neoplasm that manifests close histologic features with invasive ductal carcinoma of the breast (IDC). In contrast to SDC, extensive molecular studies have been performed on IDC and led to the identification of certain biological markers. To investigate the underlying molecular and biologic characteristics of SDC, we performed molecular analyses using microsatellite markers on chromosomal arms 6q, 16q, 17p, and 17q, DNA flow cytometry and immunohistochemical staining for androgen receptor (AR) and p53 expression on 28 examples of these tumors in comparison to 24 IDC cases. Our results show that generally similar allelic alterations, elevated p53 and androgen receptor expressions, and high frequency of DNA aneuploidy are manifested in both SDCs and IDCs. Differences at certain markers on 6q, 17p and 17q chromosomal loci, however, were observed between the two entities. Certain loci on 6q were more frequently altered in SDC than IDC which loci on chromosomes 17p and q arms were more seen in IDCs than SDCs. The majority of SDCs had high AR expression while most of IDCs were AR negative. Our study indicates that: i) SDC may share some genetic alterations with IDC, ii) high AR expression in SDC may play a role in tumor progression, and iii) p53 overexpression and DNA aneuploidy in both entities reflect their aggressive behavior.

Adult↗
PubMed2000

Papillary squamous cell carcinomas of the upper aerodigestive tract: a clinicopathologic and molecular study.

BACKGROUND: The limited studies and the small number of published cases of papillary squamous cell carcinoma have precluded accurate assessment of the biologic characteristics of this lesion. METHODS: Thirty-eight of the carcinomas were studied. In-situ hybridization and polymerase chain reaction were performed to detect human papilloma virus (HPV) and p53 expression. RESULTS: HPV was found in 4 of 14 assessable carcinomas by in-situ hybridization and in 5 of 14 by polymerase chain reaction. The most frequently identified HPVs were HPVs in 6/11 and 16/18 patients. In general, a reciprocal relationship was found between p53 and HPV prevalence. The most lethal site for this tumor was the sinonasal tract, whereas patients with papillary squamous cell carcinomas of the larynx had the best outlook. Eleven of 25 (44%) assessable patients died of disease (mean time interval, 2 year). CONCLUSIONS: Papillary squamous cell carcinoma of the upper aerodigestive tract is a distinct variant of squamous cell carcinoma. As such and because of its putative association with HPV, papillary squamous cell carcinoma could be an informative model for defining how viral oncogenes cooperate with other factors in genomic instability, carcinogenesis, and tumor development.

Adult↗
PubMed2000

Hepatosplenic candidiasis. A manifestation of chronic disseminated candidiasis.

Much progress has been made over the last decade in diagnosing and treating CDC, a chronic and debilitating infection that interferes with the delivery of intensive cytotoxic chemotherapy in patients with leukemia. The use of fluconazole prophylaxis in these patients has decreased the incidence of CDC dramatically. The greatest future challenges are gaining a better understanding of its pathophysiology, and the continued development of effective diagnostic and therapeutic strategies to treat this unusual manifestation of systemic candidiasis.

Antifungal Agents↗
PubMed2000

Salivary gland tumors of the mandible.

Primary central salivary gland carcinomas of the mandible are uncommon neoplasms. Consequently, their proper diagnosis is often in doubt. We retrospectively studied the cases of 16 patients treated at The University of Texas M. D. Anderson Cancer Center and the Institut Gustave Roussy from 1950 to 1990. Patients ranged in age from 24 to 76 years (mean, 51 years). Nine patients were women and seven were men. Each case involved either the angle or the posterior body of the mandible. Swelling, pain, and trismus were the most frequent complaints. For all patients, radiography revealed a cystic defect resembling an osteolytic odontogenic lesion or metastasis. Five histologic types of carcinoma were diagnosed: seven cases of mucoepidermoid carcinoma (five low-grade and two high-grade), four cases of adenoid cystic carcinoma, two cases of adenocarcinoma, two cases of acinic-cell carcinoma, and one case of epithelial-myoepithelial carcinoma. All patients were treated with wide surgical excision. Eight patients received postoperative irradiation. Five patients with low-grade mucoepidermoid carcinoma, two with acinic-cell carcinoma, and one with epithelial-myoepithelial carcinoma were free of disease 2 to 15 years after initial treatment (mean, 6.2 years). Two patients with adenoid cystic carcinoma are living with lung metastasis. The remaining six patients died of their carcinomas within 4 years after initial treatment. Because of their unique morphology and clinical behavior, these tumors should be distinguished from other intraosseous neoplasms of the mandible, including those with clear-cell patterns.

Adenocarcinoma↗
PubMed2000

Polymorphous low-grade adenocarcinoma: a study of 40 cases with long-term follow up and an evaluation of the importance of papillary areas.

Forty cases of polymorphous low-grade adenocarcinoma with a minimum of 10 years of follow up were reviewed. The patients included 13 men and 27 women age 22 to 71 years (median age, 54 years); 30 were white and 10 were black. The tumors were all intraoral, and the palate was the most common site (n = 24). Histologically, the neoplasms were characterized by nonencapsulated, infiltrative borders: bland, regular nuclei; and highly variable growth patterns, including tubular, solid, papillary, microcystic, cribriform (with true lumens), pseudoadenoid cystic (without true lumens), fascicular, single file, and strand-like. Papillary areas of more than focal extent were present in 17 cases, but these cases were otherwise similar to the remainder and were considered to form part of the spectrum of polymorphous low-grade adenocarcinoma. Thirteen patients had local recurrence, which was not controlled by subsequent treatment in six; six patients had cervical lymph node metastasis; three patients had distant metastasis; and five patients died of or with tumor after prolonged periods. There was a statistically significant relationship between more than focal papillary growth and cervical lymph node metastasis, and between positive or unknown surgical margins and local recurrence (although not uncontrolled local recurrence); however, these were the only independent statistically significant correlations found between any clinical or pathologic parameter and any aspect of tumor behavior or patient survival.

Adenocarcinoma↗
PubMed2000

Temporomandibular joint neoplasms and pseudotumors.

Neoplasms and pseudotumors of the temporomandibular joint (TMJ) are very uncommon. Early recognition of such will prevent therapeutic delay and may have a dramatic impact on patient morbidity and mortality. Included in rare TMJ lesions are the following: 1) synovial chondromatosis, 2) osteochondroma, 3) osteoma, 4) osteoblastoma, 5) pigmented villonodular synovitis, 6) ganglion, 7) synovial cyst, 8) simple bone cyst, 9) aneurysmal bone cyst, 10) epidermal inclusion cyst, 11) hemangioma, 12) nonossifying fibroma, 13) Langerhans cell histiocytosis, 14) plasma cell myeloma, 15) sarcoma.

Bone Cysts, Aneurysmal↗
PubMed2000

Molecular genetic alterations in carcinoma ex-pleomorphic adenoma: a putative progression model?

To determine the genetic changes associated with the development of carcinoma ex-pleomorphic adenoma (Ca Ex-PA), we analyzed 15 microsatellite loci at chromosome arms 8q, 12q, and 17p on DNA from 26 neoplasms (including 8 microdissected benign and malignant components), and 13 pleomorphic adenomas for comparison. Pleomorphic adenomas and the adenoma component of Ca Ex-PAs showed a higher incidence of loss of heterozygosity (LOH) at chromosome arms 8q (52%) and 12q (28%) than at 17p (14%) loci. In the carcinoma component, the combined LOH at chromosome arm 8q, 12q, and 17p regions was 69%, 50%, and 69%, respectively; within these chromosomal regions, 8q11.23-q12 (42%), 12q23-qter (39%), 17p13 (41%), and 17p11 (45%) loci manifested the highest incidence of LOH. Eight carcinomas (30.7%) showed loss at all three chromosomal arms tested. Of the eight microdissected Ca Ex-PAs analyzed, four adenoma and corresponding carcinoma components (50%) had the same LOH at 12q loci and additional LOH at 17p loci only in carcinomas. Chromosome arm 17p alterations correlated significantly with high disease stage and an increased proliferative rate in these tumors. Our results indicate that alterations at regions on chromosome arms 8q and/or 12q may constitute early events associated with pleomorphic adenomas; that LOH at 12q loci may identify a subset of adenoma with potential progression to carcinoma; that acquisition of additional alterations at chromosome arm 17p loci might represent an event preceding malignant transformation and progression; and that 8q, 12q, and 17p regions may harbor tumor suppressor genes involved in the genesis of PA and Ca Ex-PA. Genes Chromosomes Cancer 27:162-168, 2000.

Adenocarcinoma↗
PubMed2000

Loss of imprinting and genetic alterations of the cyclin-dependent kinase inhibitor p57KIP2 gene in head and neck squamous cell carcinoma.

The p57KIP2 is a maternally expressed and paternally imprinted cyclin-dependent kinase inhibitor located on chromosome 11p15.5. Because of its location, biochemical functions, and imprinting status, p57KIP2 has been considered a candidate tumor suppressor gene. To determine, for the first time, the involvement of this gene in the development of head and neck squamous carcinoma (HNSC), we analyzed the imprinting and expression status and loss of heterozygosity (LOH) within the p57KIP2 gene flanking loci on the 11p15.5 region in 64 primary untreated tumors. Of the 30 (47%) informative cases for this gene, loss of imprinting and LOH were noted in 4 (13%) and 10 tumors (33%), respectively. Analysis of the microsatellite markers flanking the p57KIP2 gene on chromosome 11p showed infrequent alterations at these loci. p57KIP2 was expressed in all tumors with LOH within and around the gene. Quantitative reverse transcription-PCR analysis showed elevated p57 mRNA expression in tumor with loss of imprinting. Sequencing analysis of exons 1 and 2 of the p57KIP gene failed to detect any mutations. Our data indicate: (a) infrequent genomic abnormalities at the p57KIP2 gene in HNSC; (b) leaky or incomplete imprinting of the paternal allele is associated with increased expression of this gene in a subset of tumors; and (c) minimal evidence for suppressor function for this gene in HNSC.

Carcinoma, Squamous Cell↗
PubMed1999

Expression of p16, Rb, and cyclin D1 gene products in oral and laryngeal squamous carcinoma: biological and clinical implications.

Cyclin D1, p16, and Rb genes play a critical role in the regulation of the G1-S transition of the cell cycle and are frequently altered in several neoplastic entities. Analysis of the protein products of these genes by molecular and immunohistochemical methods provides information on their functional status and allows for the phenotypic evaluation of tumor cells. We performed Western blotting and immunohistochemical analysis on tissues from 35 primary oral and laryngeal squamous carcinoma specimens with previous molecular analysis of the p16 gene and correlated the results with relevant clinicopathologic factors. Our study shows significant concordance between Western blotting and immunostaining results for cyclin D1 (P = .01), p16 proteins (P = .01), and Rb (P = .04). Heterogeneous staining of tumor cells and the positivity of non-neoplastic host elements for Rb by immunohistochemistry contributed to the discrepancy noted in some tumors by Western blotting. Significant reciprocal relationship between p16 and Rb proteins was observed (P < .001); in most tumors, absence of p16 (89%) and detectable Rb (94%) proteins were found. Two tumors had negative cyclin D1 expression, and one third overexpressed this protein. There was a lack of correlation between cyclin D1 overexpression and the clinicopathologic factors studied. Our results indicate that the absence of p16 in most of these tumors may constitute an early tumorigenic event and that the loss of the Rb function plays a minor role in HNSC.

Adult↗
PubMed1999

Sialoblastoma and epithelial tumors in children: their morphologic spectrum and distribution by age.

This commentary addresses the histologic spectrum of salivary gland neoplasms in children with emphasis on perinatal tumors. Histopathologically, perinatal tumors fall into four categories: 1) histologically benign with adult counterpart, 2) hamartomas 3) embryomas-sialoblastomas, and 4) histologically and biologically malignant adult analogue tumors. Although the criteria to serrate benign from malignant sialoblastomas are not well-established, the following histologic features would favor an aggressive clinical course: perineural and/or vascular spaces invasion, necrosis, and a cytologic atypia beyond the expected for embryonic epithelium.

Age Distribution↗
PubMed1999

Hybrid carcinomas of salivary glands. Report of 4 cases and review of the literature.

OBJECTIVE: To report 4 cases of hybrid carcinoma and to review the literature on these rare neoplasms of the salivary gland. METHODS: Hematoxylin-eosin-stained, formalin-fixed, paraffin-embedded tissue sections from 3 parotid tumors and 1 palate tumor were examined. RESULTS: The cases were classified as adenoid cystic and mucoepidermoid carcinoma, adenoid cystic and epithelial-myoepithelial carcinoma, epithelial-myoepithelial and salivary duct carcinoma, and adenoid cystic and salivary duct carcinoma. All patients were men, 28 to 71 years old; 3 patients presented with parotid mass, and 1 patient presented with palatal mass. One patient presented with facial nerve paralysis and pain. The soft palatal tumor was a slowly growing mass with maxillary sinus involvement at the time of the diagnosis. All patients were treated with surgery and radiotherapy. CONCLUSIONS: Correct identification of 2 or more neoplastic entities will help assess the aggressiveness and metastatic potential of the tumor and influence the clinical course and treatment.

Adult↗
PubMed1998

Alterations of p53, cyclin D1, Rb, and H-ras in human oral carcinomas related to tobacco use.

BACKGROUND: Epidemiologic studies have indicated that environmental and personal habits, particularly tobacco use and alcohol abuse, are major etiologic factors in the induction and progression of head and neck squamous cell carcinomas (HNSCC). Molecular studies have focused on HNSCC related to smoking but not those associated with smokeless tobacco. METHODS: The authors studied immunohistochemical evidence of alterations of p53, cyclin D1, and Rb in 34 human oral carcinomas related to tobacco use. They also examined p53 and H-ras using single strand conformation polymorphism (SSCP) and sequencing analysis. RESULTS: Overexpression of cyclin D1 was found in 41% of cases, and accumulation of p53 was found in 59%. Only 9% of the samples did not show Rb staining. In SSCP and sequencing analysis, 17 cases showed mutations in the conserved region of the p53 gene. No mutations were detected in codons 12, 13, or 61 of the H-ras gene. CONCLUSIONS: Overexpression of cyclin D1 and p53 mutations are common alterations in HNSCC. In contrast, the loss of Rb function seems to occur infrequently, and mutations in the H-ras gene apparently do not play a role in this cancer. HNSCC associated with smokeless tobacco contained the same alterations as those related to smoking.

Adult↗
PubMed1998

The prognostic significance of the biomarkers p21WAF1/CIP1, p53, and bcl-2 in laryngeal squamous cell carcinoma.

BACKGROUND: The clinical course of laryngeal squamous cell carcinoma (LSCC) varies considerably among patients. New biologic markers are needed to facilitate the stratification of individual patients within the conventional clinicopathologic stages of LSCC. METHODS: Eighty-three LSCCs from an equal number of patients who received at least 10 years of follow-up were investigated for p53, p21WAF1/CIP1, and bcl-2 protein expression by immunohistochemical techniques. The results were correlated with various clinicopathologic parameters, DNA content, and patient outcome by univariate and multivariate statistical analyses. RESULTS: Stage IV disease, large tumor size (>3 cm), positive lymph node status, extranodal extension, and p53 overexpression (in > 75% of cells) correlated significantly with prognosis in univariate analysis. There was no correlation between patient outcome and age, gender, race, histologic differentiation, or expression of bcl-2 or p21WAF1/CIP1. In multivariate analysis, lymph node status and p53 overexpression were the only factors significantly associated with survival. CONCLUSIONS: High p53 expression and positive lymph node status were independent predictors of the outcomes of patients with LSCC. These factors may assist in prognostication and better classification of patients for treatment.

Adult↗