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A Meneses-García

Publications and source records attributed to A Meneses-García.

9 recordsLinked to original sources
PubMed2001

Tumor angiogenesis as a prognostic factor in oral cavity carcinomas.

Currently, lymph node metastasis and thickness of the tumor are the gold standard as a predictor of survival in patients with oral cavity squamous cell carcinoma (OSCC). However, there is a significant correlation between microvessel density and the development of cervical metastases or recurrence. Previous studies have demonstrated that head and neck cancers are able to induce an angiogenic response in experimental models. This factor shows a strong correlation with regional recurrence. In this study we propose to use angiogenesis as an independent prognostic indicator of recurrence. We evaluated the expression of tumor angiogenesis in OSCC and determinated its possible usefulness as a prognostic factor. Thirty-three cases with diagnosis of OSCC were identified from January 1985 to January 1997 in the Head and Neck Department of the Instituto Nacional de Cancerología in Mexico City. These cases were analyzed retrospectively for a minimum period of six months. All of them received a conventional complete treatment to the primary tumor and lymph node metastasis. Paraffin-embedded tumor specimens were available in all patients. The tumors were scanned and the areas of highest microvessel density (MVD) were immunostained for CD-34 using QBEnd/10 antibody. Statistical analysis included descriptive statistics, Wilcoxon test curves, and Cox's proportional hazards model for multivariate analysis. We identified 33 patients with OSCC, 16 were men and 17 women. The mean age among all patients was 58.9 years old. Based on tumor size 33.3% were T1, 27.3% T2, 12.1% T3, and 27.3% T4. The median microvessel count was 32.5. The mean percentage of MVD was 37 in patients with regional recurrence and in those patients without regional metastasis was 29 (p<0.05). 57.9% of the patients who presented recurrence had vessel counts over the median (p<0.01). In fact, 6 patients (46%) who showed more than 20% of angiogenesis expression and higher MVD presented with recurrence. Only 3 patients (23%) who had less than 20% of angiogenesis expression and lower MVD developed recurrence (p<0.01). Higher MVD was seen with increasing T and N stages; however, it did not show correlation with survival. In this study, angiogenesis expression demonstrated to be an independent factor of recurrence in patients with OSCC. It is suggested that it should be used as an independent prognostic indicator. In concordance with previous reports, we observed a significant correlation between MVD determination and recurrence of the tumor, followed by lymph node metastases and tumor size.

Adult↗
PubMed1999

Well-differentiated intraosseous osteosarcoma of the jaws: experience of two cases from the Instituto Nacional de Cancerología, México.

Osteosarcomas of the jaws represent less than 10% of all osteosarcomas, and most of them are high-grade neoplasms. Prognostic factors in overall survival include tumor size, location and histologic grade. Examples of well-differentiated (low-grade) intraosseous osteosarcomas of the jaws (WDIOJ) have been rarely reported. This article presents two cases of this unusual lesion, one of which was located in the maxilla of a 17-year-old man and the other developed in the mandible of a 37-year-old woman. CT scan was necessary to detect the small foci of penetration into the thinned cortical bone and the reactive periosteal bone formation, which are important findings to establish the correct diagnosis of WDIOJ and help to exclude other benign intraosseous lesions that may be very similar histologically, such as fibrous dysplasia, ossifying and desmoplastic fibromas. In spite of tumor size (mean 5.2 cm), their well-demarcated borders allowed complete removal of both tumors. There is no evidence of tumoral activity in any of our patients after follow-up periods of 15 months and 5 years. Wide excision seems to be the treatment of choice for this subgroup of osteosarcomas.

Adolescent↗
PubMed1999

Malignant melanoma of the oral cavity: diagnosis and treatment experience in a Mexican population.

Oral malignant melanoma is uncommon, accounting for 1-8% of all malignant melanomas. All previous papers have reported small numbers of cases or have retrospectively reviewed case reports from the literature. The following case reports concern malignant melanoma of the oral cavity seen at the Instituto Nacional de Cancerología, Mexico City, during the period of 1982-96. Demographic, clinical and histopathological data were collected. Our 15 patients consisted of 6 males and 9 females. The mean age was 52.6 years (range: 35 to 80 years). The hard palate was the most common area affected with 11 cases (73%). At the time of the initial examination, a pigmented mass was apparent in 100% of the patients. All our surgical cases were treated with wide resection; 8 patients received adjuvant radiation, 4 were treated with surgery alone and 1 case received radiation and chemotherapy before the surgery. Local control of the primary lesion was possible in 14 of the 15 cases. Some patients received therapeutic or elective lymph node dissection. The median survival was 16.9 months (mean: 12.5 months). The 2- and 5-year survival rates were 26.6 and 6.6%, respectively.

Adult↗
PubMed1997

Odontogenic tumors in Mexico: a collaborative retrospective study of 349 cases.

Reports about the frequency of odontogenic tumors are scarce, and diagnostic criteria used in the reports are not uniform. This article presents the results of a retrospective study of odontogenic tumors recorded in four services of diagnostic pathology in Mexico City (two dental schools, one cancer hospital, and one private oral pathology service). The final diagnosis in each case was based on the 1992 histologic criteria of the World Health Organization. The frequency of odontogenic tumors, expressed as a percent of all oral and maxillofacial specimens, ranged from 0.8% in the cancer hospital (0.02% of all biopsies) to 3.7% in the private oral pathology service. The frequency was identical for the two dental schools (2.5%). We found a total of 349 odontogenic tumors; of these, 345 were benign (98.8%), and 4 (1.1%) were malignant (3 were primary intraosseous carcinomas and 1 was a malignant ameloblastoma). The most frequently occurring tumors were odontoma (34.6%), ameloblastoma (23.7%), myxoma (17.7%), adenomatoid odontogenic tumor (7.1%), and calcifying odontogenic cyst (6.8%). Although relatively rare, odontogenic tumors are still an important cause of extensive surgical procedures in Mexico.

Adolescent↗
PubMed1997

Angiocentric lymphomas of the palate: clinico-pathological considerations in 12 cases.

Angiocentric lymphomas (AL) involving the mid-face are infrequent lesions. Their incidence seems to be higher in certain Asian and Latin American countries, where most of the reported series reveal a predominance of T-cell lineage and a high frequency of EBV-positive cells. The clinical and pathological features of 12 AL that affected the palate are presented. Immunophenotypic studies were performed in nine of these cases. Seven (77%) demonstrated T-cell lineage, one was of B-cell origin and one could not be classified. The high incidence of T-cell lesions in this and other studies supports the existence of geographical and possibly of etiological differences in these neoplasms.

Adolescent↗
PubMed1989

[Bronchial mucoepidermoid carcinoma in a child].

A case of mucoepidermoid carcinoma in a seven year old girl is reported. This represents the eleventh case of this bronchial neoplasm seen in pediatric ages. For our knowledge this is first case which corroborates by immunohistochemistry, it originates from the salivary bronchial glands. The poor knowledge of this illness frequently delays its diagnosis. We are obligated to report these types of cases in order to have a better understanding of the clinical and pathological presentation of the lesion.

Bronchial Neoplasms↗
PubMedDate not supplied

[Laparoscopic partial hepatectomy. Report of the first case in Mexico].

The authors report the case of a 47-year-old female patient referred to the Instituto Nacional de Cancerología with abdominal pain and a focal liver lesion in the left lateral segment. After a careful tumor work-up, a laparoscopic left lateral segmentectomy was performed. The postoperative course was uneventful and the patient was discharged at the 2nd postoperative day. Histologic examination revealed focal nodular hyperplasia. In a search of the literature we find this to be the first case treated by this approach in Mexico.

Female↗
PubMedDate not supplied

[Expression of cathepsin D in breast cancer and its clinical and histopathological correlations].

BACKGROUND: Cathepsin D is a lysosomal protease which is overexpressed in some cases of breast cancer. Several studies done in tumor cytosol have shown that high levels of cathepsin D are associated with poor prognosis in patients with breast cancer but the results are not conclusive using immunohistochemistry methods to assay cathepsin D. OBJECTIVE: To evaluate if cathepsin D, assayed by a immunohistochemical technique using a polyclonal antibody, can be considered an independent prognostic factor in breast cancer. PATIENTS AND METHODS: Paraffine embedded sections of 68 tumor specimens from breast cancer patients in stages I to IV seen at the Instituto Nacional de Cancerologia during the period from 1985 to 1986. RESULTS: From the 68 patients, 35 (51%) had an intense positive staining for cathepsin D, 19 (28%) han mild staining and 14 (21%) were negative. Ten patients with mild staining had artifacts due to deficiencies in the tissue fixation technique. Cathepsin D expression did not have a prognostic value nor association with other clinical and histopathological prognostic factors well established in breast cancer. CONCLUSION: Cathepsin D determined by immunohistochemistry has no prognostic value in breast cancer.

Adult↗