Search PubMed⌕ Search

Biomedical subjects

A el-Naggar

Publications and source records attributed to A el-Naggar.

At least 19 recordsLinked to original sources
PubMed2000

Mucoepidermoid carcinoma involving Warthin tumor. A report of five cases and review of the literature.

We describe 5 cases of mucoepidermoid carcinoma (MEC) involving Warthin tumor (WT) of the parotid gland. The WT size ranged from 1.7 to 6.0 cm. The MECs were much smaller, 0.3 to 1.7 cm. In 3 cases, the WT completely surrounded the MEC, and in 2 cases neither WT nor MEC surrounded the other. Each MEC was low grade, 3 grade I and 2 grade II. One MEC had evidence of vascular invasion. All patients underwent partial or subtotal parotidectomy with negative resection margins. Clinical follow-up (range, 8-52 months) for 3 patients showed no evidence of recurrence. The pathogenetic relationship between WT and MEC in these cases is uncertain. In 4 cases, foci of squamous or mucous metaplasia were found in the WT component, associated with mild cytologic atypia in 3 tumors. However, a direct transition from WT to MEC was not identified. In 1 case, MEC was present 45 months before WT, suggesting that the recurrent MEC involved WT coincidentally. The small size and low grade of the MEC and the negative resection margins most likely explain the good outcome for the 3 patients with clinical follow-up data available.

Adenolymphoma↗
PubMed1999

p53 mutations and expression in ovarian cancers: correlation with overall survival.

The p53 gene is altered in approximately 50% of all human malignancies. p53 overexpression, identified by immunohistochemistry, and p53 mutations, identified by single-strand conformational polymorphism (SSCP) and DNA sequencing, have been described in ovarian cancers. p53 overexpression has been correlated with poor outcome for women with ovarian cancer in some studies. With only limited data, the assumption has been made that p53 overexpression corresponds to p53 mutations. The purpose of this investigation was to assess p53 alterations in ovarian cancer to determine if p53 overexpression corresponds with mutations in the p53 gene, and to assess whether either predicts clinical outcome in ovarian carcinoma. Frozen ovarian carcinoma tumor specimens from 105 patients were analyzed by immunohistochemical staining for p53 expression. SSCP was used to screen for mutations and DNA sequencing was used to confirm the specific mutation in exons 2 to 11, encompassing the entire p53 open reading frame. Those ovarian carcinomas identified as wild-type p53 by SSCP were subjected to automated DNA sequence analysis of the entire open reading frame. Relative to DNA sequence analysis, the sensitivity of SSCP was 85% and the specificity was 98%. Immunohistochemical staining demonstrated that 72 of the 105 (69%) cases had positive immunostaining. SSCP and DNA sequencing identified and confirmed mutations in 60 of the 105 carcinomas (57%). Although there was a statistically significant association between p53 immunostaining and p53 mutations (p = 0.0002), false-negative and -positive results were identified. Tumor grade (p = 0.03), stage (p = 0.08), and overall survival (p = 0.15) were moderately associated with positive p53 immunostaining. Patients with p53 mutations and overexpression had shorter overall patient survival (p = 0.02). The findings demonstrated that, individually, p53 mutations and p53 overexpression were each related to shorter patient survival, but the strongest predictor of outcome was a combination of both mutations and overexpression. Comparisons of overall survival for women with mutations in loop 2, loop 3, and the loop-sheet-helix domains together showed a statistically significant difference in survival compared to survival of women whose ovarian cancers had other mutations (p = 0.046).

Adult↗
PubMed1997

The induction of benign epithelial neoplasms of the ovaries of guinea pigs by testosterone stimulation: a potential animal model.

We studied the effects of different hormones on the epithelial cells of the ovaries of 11 guinea pigs. Three received testosterone, two received estrone, three megestrol, and three chorionic gonadotropin. Three control guinea pigs received sterile water. Benign epithelial cysts larger than 1.5 mm were found in six guinea pigs, three who received testosterone, one who received megestrol, and two who received chorionic gonadotropin. In one of the three guinea pigs who received testosterone, 2.5-cm bilateral cysts were grossly identified. Papillary excrescences were found on the ovarian surface in four guinea pigs, three who received testosterone and one who received megestrol. The proliferating epithelial cells also formed benign glands in the ovarian stroma in two guinea pigs who received testosterone, the most exuberant epithelial proliferations, including large bilateral cystadenomas, papillary excrescence that formed a small papillary neoplasm, and glands in the ovarian stroma that formed adenomatous areas, were seen in the guinea pig who received an intermediate dose of testosterone for the longest time. By radioimmunoassay, the serum level of testosterone was 22 ng/dL in one of the controls and 10,000, 12,000, and 15,000 ng/dL in the three guinea pigs who received testosterone. In the guinea pig with the most exuberant epithelial proliferation, the level of testosterone in the uterus was similar to that in the serum (13,860 ng/mg), but in the wall of the ovarian epithelial cyst, it was three times higher than it was in the serum (44,000 ng/mg). Our study shows that testosterone stimulates the growth of epithelial cells in the ovaries of guinea pigs, resulting in benign cysts, small adenomas in the ovarian parenchyma, and papillomas on the ovarian surface. The study also shows that guinea pigs can be used as an animal model for epithelial tumors of the human ovary.

Animals↗
PubMed1996

Flow cytometric analysis of apoptosis and bcl-2 in primary breast carcinomas: clinical and biological implications.

Analysis of programmed cell death (apoptosis), of bcl-2, a critical regulator of this process, and of the proliferative fraction may provide detailed information on the biologic characteristics of tumor cell populations. To investigate the potential role of these parameters in assessing mammary carcinoma, we adapted flow cytometric procedures for concurrent measurement of apoptosis, bcl-2 expression, and cell proliferation in 54 primary breast carcinomas and correlated the findings with traditional clinicopathologic information. Overall, a significant inverse relationship between apoptosis levels and bcl-2 expression was observed (P = 0.005). Apoptosis levels correlated significantly with DNA aneuploidy (P = 0.03) and S + G2M fractions (P = 0.005) of these tumors. A significant correlation between bcl-2 expression and estrogen receptor positivity (P = 0.05) and DNA diploidy (P = 0.02) was noted. Bcl-2 expression, however, was inversely correlated with S + G2M fractions (P = 0.001). We conclude that analysis of apoptosis and bcl-2 by flow cytometry allows further characterization of tumor cell populations that may be useful for prognostic and therapeutic management of breast carcinoma.

Adult↗
PubMed1995

Amplification and overexpression of HER-2/neu (c-erbB2) in endometrial cancers: correlation with overall survival.

Few molecular genetic alterations have been identified in endometrial cancers that are associated with poor clinical outcome. Overexpression of HER-2/neu, transforming growth factor alpha, and p53 proteins have all been associated with poor prognosis in women with endometrial cancer. In this study, the level of HER-2/neu gene amplification and expression was characterized in 92 endometrial cancers. Fluorescence in situ hybridization (FISH) was used to characterize HER-2/neu gene copy number, and immunohistochemistry was used to characterize expression. Forty-seven of the 90 (52%) endometrial cancers were characterized as showing moderate or high immunostaining. HER-2/neu gene amplification was detected in 17 of 81 (21%) cases. Immunohistochemical staining and FISH results were both available for 80 cases. Fourteen of these cases showed both moderate or high immunostaining and gene amplification. Clinical follow-up information was available for 76 women in this study. Women whose endometrial cancer exhibited HER-2/neu gene amplification by FISH had a shorter overall survival than women whose endometrial cancer lacked amplification (P = 0.018). Likewise, tumors with moderate or high HER-2/neu immunostaining were associated with a lower cumulative overall survival than tumors with low immunostaining by log rank analysis (P < 0.0001). Multivariate analysis of survival rates revealed HER-2/neu overexpression to be an independent predictor of overall survival (P = 0.0163). Among those patients with HER-2/neu overexpression, adjuvant chemotherapy or radiation therapy was associated with an improved overall survival (P = 0.039). However, among those women whose tumor lacked overexpression, overall survival was not improved by adjuvant treatment.

Adult↗
PubMed1995

Rhabdomyosarcoma of the nose and paranasal sinuses in adults and children.

OBJECTIVE: To determine the biologic behavior, risk factors for recurrence, and influence of multimodality therapy on outcome for children and adults with rhabdomyosarcoma of the nose and paranasal sinuses. DESIGN: Retrospective review of medical records. PATIENTS: During a 36-year period 37 patients (median age, 23.0 years) with histologically confirmed rhabdomyosarcoma of the nose and paranasal sinuses were treated for cure. Median follow-up was 28 months (range, 1 to 260 months). Histologic subtypes included embryonal, 16; alveolar, 15; mixed, 1; and unclassified, 5. Cervical metastases were present in 38%. Patients were treated with surgery, 4; radiotherapy, 3; chemotherapy, 3; surgery and radiotherapy, 1; surgery and chemotherapy, 1; chemotherapy and radiotherapy, 24; and chemotherapy, radiotherapy, and surgery, 1. RESULTS: The overall 5-year survival was 44%. For patients treated with chemotherapy and radiotherapy or chemotherapy, radiotherapy, and surgery, the 5-year survival was 60%, compared with 19% for patients treated with the other forms of therapy. Factors associated with poorer survival were adult onset of disease, alveolar histology, and treatment with systemic chemotherapy for less than 1 year. Patients receiving chemotherapy for greater than 1 year had a 5-year survival of 82%, compared with 71% for those with less than 1 year of treatment. Improved survival was associated with a lower incidence of distant metastasis. CONCLUSIONS: A combination of chemotherapy and radiotherapy may provide the best means of obtaining local-regional control for rhabdomyosarcoma arising in the nose and paranasal sinuses. The risk of regional disease is high, requiring comprehensive radiotherapy to the neck in addition to the primary site. Surgical resection should be reserved for patients with residual disease after chemotherapy and radiotherapy. Administration of chemotherapy for more than 1 year is associated with improved survival because of a decreased incidence of metastatic disease.

Adolescent↗
PubMed1994

A tumor suppressor locus within 3p14-p12 mediates rapid cell death of renal cell carcinoma in vivo.

High frequency loss of alleles and cytogenetic aberrations on the short arm of chromosome 3 have been documented in renal cell carcinoma (RCC). Potentially, three distinct regions on 3p could encode tumor suppressor genes involved in the genesis of this cancer. We report that the introduction of a centric fragment of 3p, encompassing 3p14-q11, into a highly malignant RCC cell line resulted in a dramatic suppression of tumor growth in athymic nude mice. Another defined deletion hybrid contained the region 3p12-q24 of the introduced human chromosome and failed to suppress tumorigenicity. These data functionally define a tumor suppressor locus, nonpapillary renal carcinoma-1 (NRC-1), within 3p14-p12, the most proximal region of high frequency allele loss in sporadic RCC as well as the region containing the translocation breakpoint in familial RCC. Furthermore, we provide functional evidence that NRC-1 controls the growth of RCC cells by inducing rapid cell death in vivo.

Animals↗
PubMed1994

Comparative flow cytometric analysis of proliferating cell nuclear antigen (PCNA) antibodies in human solid neoplasms.

Proliferating cell nuclear antigen (PCNA), an auxiliary protein of DNA polymerase delta, associated with DNA synthesis, is increasingly used to determine tumor growth rate. To determine the growth fraction by PCNA, various antibodies and fixation procedures are being used. We assessed the flow-cytometric measurement of PCNA using three monoclonal antibodies (PC10, 19F4, and 19A2) and two fixation protocols (paraformaldehyde and methanol) in tissue-culture cell lines and human solid neoplasms to determine their potential clinical application. Thirty-one solid tumors and four normal tissues were analyzed, along with MOLT-4 and HL-60 cell lines as positive controls and normal peripheral blood lymphocytes as a negative control. PC10 with methanol fixation consistently detected higher PCNA positivity in human solid neoplasms than 19F4 and 19A2. Using PC10, the differences in positivity among fixation methods occurred in the G0/1 phase, not in S + G2M, of the cell cycle. No correlation was found between PCNA positivity and tumor grade and DNA ploidy in tumors analyzed. A statistical correlation was found between overall PCNA positivity and RNA content as determined by acridine orange analysis. The growth fraction by PCNA in solid neoplasms was most reliably determined by PC10 with methanol fixation.

Antigens, Neoplasm↗
PubMed1994

Surgical management and prognostic factors in patients with subungual melanoma.

OBJECTIVE: Forty-six cases of subungual melanoma were reviewed to identify significant clinicopathologic prognostic factors, determine the role of DNA content analysis in the biologic assessment of these tumors, and evaluate the effectiveness of amputation level, lymph node dissection (LND), and regional limb perfusion on the survival of these patients. BACKGROUND: Subungual melanoma is a unique and rare subtype of melanoma, constituting only 1% to 3% of cases. Thus, little is known about prognostic factors and optimal management of patients with this disease. Moreover, the appropriate level of amputation and LND and limb perfusion in the management of subungual melanoma remain controversial. METHODS: Forty-six patients underwent amputation alone or in combination with LND and/or regional limb perfusion for primary subungual melanoma. The effects of these treatment modalities and the prognostic significance of patient and tumor-related variables, including DNA flow cytometric data, on overall survival were assessed. RESULTS: Univariate statistical analysis identified six factors that significantly affected patient survival. They were stage at diagnosis (p = 0.0001), percentage of aneuploid cells (p = 0.01), presence of ulceration (p = 0.02) or bone invasion (p = 0.02), thickness of the primary lesion (p = 0.03), and percentage of cells in S-phase (p = 0.03). Multivariate analyses identified tumor stage and S-phase fraction as independent prognostic factors in these patients. Survival did not differ among patients who received amputation alone or those who underwent amputation in combination with LND or perfusion (p = 0.90); however, the use of limb perfusion reduced the incidence of locally recurrent disease. The level of amputation did not affect patient survival (p = 0.74) or the incidence of local recurrence. CONCLUSIONS: The study identified several significant prognostic factors, including DNA flow cytometric parameters, in patients with subungual melanoma. In addition, it showed that conservative amputation of the affected digit at the level of the proximal interphalangeal or metacarpophalangeal/metatarsophalangeal joint appears to be safe, provided that clear margins are obtained. Although isolated limb perfusion may reduce the incidence of local recurrence, LND, or limb perfusion in the routine management of subungual melanoma remains controversial.

Adult↗
PubMed1994

Mediastinal lymphoblastic lymphoma with non-lymphoblastic histologic features.

The clinical and pathologic features of an unusual case of mediastinal lymphoma in a 46-yr-old man are presented. Histology of the tumor was that of a diffuse, non-large cell lymphoma. The nuclear chromatin was coarse, suggesting a relatively mature stage of lymphocyte maturation, and the lymphoma was provisionally classified as diffuse small-cleaved cell lymphoma. Immunohistologic study and cell surface marker analysis revealed a common thymocytic phenotype (CD3, CD1a, CD4, CD8, and TdT positive), however, and DNA flow cytometric analysis revealed a high S+G2 M fraction of 29%. With the immunostaining profile accepted as definitive for lymphoblastic lymphoma, histologic features were reassessed in retrospect. Cells having nuclear features typical of lymphoblasts were not recognized. Occasional cases of lymphoblastic lymphoma may not be recognizable when evaluated only by histology using the generally accepted criteria for diagnosis.

Cell Cycle↗
PubMed1993

Primary carcinoid tumor of testis. Immunohistochemical, ultrastructural, and DNA flow cytometric study of three cases with a review of the literature.

The cases of three patients with primary carcinoid tumor of the testis were reported. The patients were 41, 44, and 83 years of age. At initial examination, all three had testicular masses with or without associated pain, and none had the carcinoid syndrome. The tumors measured 4.3 cm, 3.0 cm, and 6.5 cm in dimension. All three tumors manifested classic histologic features of carcinoid tumors. The neoplastic cells exhibited argyrophilia, and all were immunoreactive to chromogranin, serotonin, neuron-specific enolase, and cytokeratin. Two tumors had positive test results for gastrin and one had positive test results for substance P and vasoactive intestinal polypeptide. No tumors reacted with somatostatin, insulin, pancreatic polypeptide, or placental alkaline phosphatase. Intracytoplasmic, membrane-bound, round-to-elliptical pleomorphic granules were identified by ultrastructural analysis in all cases. DNA flow cytometric analysis revealed a low degree (near-diploid) DNA aneuploidy in all cases, with a DNA index of 1.15 in two tumors and 1.3 in the third tumor. The three patients are alive and well 11 years, 7 years, and 6 months, respectively, after diagnosis. A total of 57 cases of this entity, including the 3 reported here, have been reported. Of these, 43 were pure carcinoid, and 14 were associated with teratoma; 6 (11.6%) patients developed metastases. Tumor size and the presence of carcinoid syndrome have been found to correlate with metastatic potential. Neither tumor necrosis nor local tumor invasion (into vessels, tunica albuginea, etc.) correlated with adverse prognosis. Carcinoid tumor of the testis is a rare indolent neoplasm with potential for distant metastases.

Adenocarcinoma↗
PubMed1993

Regulation of urokinase-type plasminogen activator expression in squamous-cell carcinoma of the oral cavity.

We undertook a study to determine the role and regulation of expression of urokinase-type plasminogen activator in squamous-cell carcinoma of the oral cavity. The contribution of urokinase to the invasive process was clearly demonstrated in experiments in which in vitro invasion by a cultured squamous-cell carcinoma cell line was substantially reduced by a monoclonal antibody directed at the catalytic site of urokinase. The conditioned medium from 2 invasive cell lines contained high levels of urokinase. Examination of resected tumors for urokinase revealed (a) localization of the antigen to the tumor cells and (b) higher levels of the plasminogen activator in tumor tissue than in adjacent non-malignant tissue. These results suggested that elevated expression of urokinase is a common feature of this malignancy. The mRNA half-lives of cell lines expressing high and low levels of urokinase were similar, indicating that elevated levels of mRNA for the plasminogen activator were not a consequence of a more stable transcript. No evidence of u-PA gene amplification was obtained by Southern blotting of DNA derived from the cell lines expressing high urokinase levels. Transfection of squamous-cell carcinoma cells, which express high levels of urokinase, with a construct bearing the chloramphenicol acetyl transferase gene driven by the full-length (2345 bp) urokinase promoter indicated activation of the urokinase promoter in trans. In conclusion, our results suggest that transcriptional activation of the urokinase gene, in squamous-cell carcinomas of the oral cavity, leads to elevated levels of urokinase mRNA/protein which, in turn, can promote the invasive phenotype.

Blotting, Western↗
PubMed1993

Basaloid squamous carcinoma of the head and neck. Immunohistochemical comparison with adenoid cystic carcinoma and squamous cell carcinoma.

Basaloid squamous carcinoma (BSC) is a rare distinct variant of squamous cell carcinoma of the head and neck region. This entity may commonly pose diagnostic difficulties, especially on small biopsy material. We report the clinicopathological characteristics of 12 new cases and compare their immunohistochemical features with those of solid adenoid cystic carcinomas and conventional squamous cell carcinomas. Our results show that neoplastic BSCs and squamous cell carcinomas do not react to vimentin and S100 protein, while adenoid cystic carcinomas manifest both. The BSCs, however, are S100 protein-positive in intratumoral dendritic Langerhans' cells that are lacking in squamous cell and adenoid cystic carcinomas. Our findings indicate that the immunohistochemical differences between BSC and adenoid cystic carcinoma could assist in their differential diagnosis.

Aged↗
PubMed1993

Prognostic implications of DNA index in patients with stage III cutaneous melanoma.

DNA flow cytometry of the lymph node metastases from 56 patients was used to retrospectively evaluate the prognostic significance of DNA ploidy in patients with stage III melanoma. The findings were correlated with traditional prognostic factors and patient survival. Multivariate regression analysis revealed that, in addition to the number of positive lymph nodes and patient gender, the DNA index was a significant predictor of patient survival (all p < 0.03). Within this cohort of patients, the patients with the poorest prognoses were those with DNA indices greater than 2 (at least tetraploid), more than three positive lymph nodes, and male gender. There was a significant survival difference among the patients having zero, one, or two of these risk factors (p < 0.001). Our results indicate that DNA analysis of melanoma metastases by flow cytometry provides an additional discriminating factor for predicting patient outcome after therapeutic lymph node dissection. This information may be useful in directing patients with stage III melanoma at higher risk for recurrence into clinical trials of more aggressive systemic adjuvant therapy.

Adolescent↗
PubMed1993

Keratins 6, 13 and 19. Differential expression in squamous cell carcinoma of the head and neck.

One hundred forty-one head and neck squamous cell carcinomas were analyzed for keratin (K) 6, 13 and 19. Staining was evaluated by light microscopy (with or without grading) and image analyzer and expressed as a percentage of positive versus all tumor surface (PSA). Both techniques rendered strongly correlated results. Strong expression was noted in 108 carcinomas (76.1%) for K6, in 18 (12.7%) for K19 and in 21 (14.8%) for K13 (P = .001). One hundred thirty-six (96%) tumors were positive for K6, and their PSA ranged from 0.6% to 48.8%; K19, 48 cases (0.2-44%); K13, 59 (0.2-38.1%). Expression of K6 was related to differentiation. K19 was expressed mainly in moderately and poorly differentiated tumors, and K13 was manifest more in well-differentiated carcinomas or in keratinized areas of less-differentiated ones. Nineteen (13.38%) tumors were positive for both K13 and K19. K19 thus was related to tumor progression and K13 to differentiation. There was no correlation with tumor site or TNM category.

Adult↗