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R González-Cámpora

Publications and source records attributed to R González-Cámpora.

At least 19 recordsLinked to original sources
PubMed2004

Ki-ras mutational analysis in rat follicular-cell proliferative lesions of the thyroid gland induced by radioactive iodine and potassium perchlorate.

Although in both human and experimental pathology ras mutations have been related to the origin and progression of follicular-cell tumours, reports differ considerably with respect to the frequency of such mutations. The present paper reports, using direct sequencing, the incidence of Ki-ras mutations (codons 12 and 13) in follicular-cell carcinomas of the thyroid gland in Wistar rats induced by administration of radioactive iodine and potassium perchlorate. Direct sequencing revealed no mutations in the amplified gene segment of any of the 72 carcinoma samples studied. This absence of mutations agrees with some and is in sharp contrast with other previous reports in the literature, both for experimental animals and in studies of human thyroid follicular-cell carcinoma. Our results suggest that Ki-ras activation via mutations at codons 12 and 13 is neither a constant event nor an early event in the development of rat thyroid follicular-cell carcinoma.

Adenocarcinoma, Follicular↗
PubMed2000

P-glycoprotein, metallothionein and NM23 protein expressions in breast carcinoma.

Cellular drug resistance and increased metastatic potential are the major obstacles in the successful treatment of cancer with chemotherapy. The aim of this study was to investigate whether the immunohistochemical expression of two proteins implicated in drug resistance (P-glycoprotein and metallothionein) and the product of the suppressor gene nm23 could be related to prognosis in breast cancer. Seventy-two patients with palpable or occult breast carcinoma, not treated with chemotherapy or endocrine therapy, were examined. Immunohistochemical methods were used to determine the expression of P-glycoprotein (PG), metallothionein (MT), nm23, as well as the estrogen receptor (ER), the p53 status, and the Ki67 index. The results were correlated with clinical and morphological features. Cytoplasmic and membrane-specific immunostainings of PG were seen exclusively in tumor cells and identified in 14 of 72 cases (19.4%). Only a statistically significant association with metastases, (p = 0.06) and recurrences (p = 0.1) was observed. MT-positive reaction was identified in the cytoplasm of the tumor cells in 47 (65.3%) cases. Statistical significance was associated with metastases (p = 0.07), but not with death or recurrences. Specific immunostaining of nm23 protein was seen only in the cytoplasm of tumor cells. A positive reaction was observed in 55 of 72 (89.3%) cases. Although a significant association between nm23 protein expression and other morphologic and immunohistochemical variables did not exist, we observed a higher morbidity in patients with the MT-positive/nm23-negative tumor phenotype. Univariate analysis for survival selected the following variables: histologic grade (p = 0.001), ER (p = 0.002), mitotic index (p = 0.005), Ki 67 index (p = 0.068), MT (p = 0.046) and PG (p = 0.085). The Cox model provided the following independent variables: histologic grade (p = 0.021) and metallothionein (p = 0.03). These data confirm the prognosis observed in patients with PG or metallothionein expression as well as the independence of these two variables. It also suggests that nm23 is not necessarily involved in the development of an invasive phenotype.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Apoptosis in breast carcinoma.

Apoptosis may play a major role in determining tumor growth and aggressiveness. The aim of this study was to examine the relationship between apoptosis, expression of bcl-2 and p53 proteins, proliferation index, and other clinicopathological features of breast carcinoma. Sixty-five formalin-fixed paraffin-embedded tissue sections from invasive ductal breast carcinomas were studied for the presence of apoptosis by the terminaldeoxynucleotidyl-transferase-mediated dUTP-FITC nick end-labeling (TUNEL) method. Immunohistochemical methods were also used to determine the expression of estrogen receptor, Ki67, bcl-2 and p53 proteins. The number of apoptotic cells ranged from 2.0 to 236.0/10HPF (mean 36.26, median 28.0). The observation of 30 apoptotic cells/10HPF was more common in tumors > 3 cm, of histological grade III, with a high mitotic index, Ki67 index > or = 300, and p53 positivity; however, statistical significance was found only for the histological grade. Grade I and III tumors displayed an inverse association between the apoptotic index and bcl-2 and p53 protein expressions; grade I tumors frequently expressed bcl-2 (19/28), lacked p53 (20/28), and presented a low number of apoptotic cells (18/28), whereas grade III tumors tended to express p53 (12/17), lacked bcl-2 (13/17), and displayed a high number of apoptotic cells/10HPF (12/17). Multivariate analysis for survival revealed that estrogen receptors and apoptosis were independent variables. These data suggest that apoptosis, rather than proliferation index or expression of bcl-2 or p53 proteins, is an independent factor for the prognosis of survival.

Adult↗
PubMed1998

Dipeptidyl aminopeptidase IV in the cytologic diagnosis of thyroid carcinoma.

Recently, the demonstration of DAP IV activity in thyroid cells aspirates has been proposed as an useful tool for the diagnosis of malignancy. We have studied the enzymatic activity of DAP IV, using the modified method of Lodja, in a series of 336 selected aspirates of the thyroid gland with the following cytologic diagnosis: 236 nodular hyperplasias, 60 follicular proliferations, eight Hashimoto's thyroiditis, eight Hürthe-cell proliferations, 20 papillary carcinomas, two anaplastic carcinomas, and two medullary carcinomas. The results were subjectively evaluated on the basis of staining intensity and extension in a minimum of 200 cells. Strong-to-moderate enzymatic activity with an extension of more than 40% of the cells were exclusively seen in follicular-cell derived carcinomas (papillary carcinoma, Hürthle-cell carcinoma, and follicular carcinoma). Medullary carcinoma, anaplastic carcinoma, and benign conditions were negative or weakly stained. Cytohistologic correlation in 88 patients operated on showed the following results: 26 nodular hyperplasia (18 nodular hyperplasia and eight follicular adenomas), 36 follicular proliferation (24 nodular hyperplasia, six, adenomas, three papillary carcinomas, three follicular carcinomas), two Hürthle-cell proliferation (one Hürthle-cell adenoma and one Hürthle-cell carcinoma), 20 papillary carcinomas, two medullary carcinomas, and two anaplastic carcinomas. DAP IV staining was moderate to strong and extensive in all malignant tumors initially diagnosed as follicular or Hürthle-cell proliferations. We conclude that DAP IV activity is present in malignant differentiated thyroid tumors of follicular cells (papillary carcinoma, follicular carcinoma, Hürthle-cell carcinoma), but it is identified neither in medullary carcinoma nor in anaplastic carcinoma. Therefore, its usefulness is restricted to the diagnosis of follicular-cell malignancies.

Adenocarcinoma↗
PubMed1998

Lipidized mature neuroectodermal tumour of the cerebellum with myoid differentiation.

We describe a case of a lipidized cerebellar tumour in a 67-year-old woman with immunocytochemical evidence of neurocytic, astrocytic, and in addition, striated muscle cell differentiation. A review of the literature on lipidized cerebellar tumours shows that they present in adults (mean age 58.8 years); they tend to occur in the hemispheric or paramedian regions of the cerebellum and are hypodense on CT scan and MRI. Histologically they are well differentiated and share some common features, such as extensive lipidization, low mitotic rate and an absence of pleomorphism, necrosis and capillary endothelial proliferation. The present case emphasizes the occurrence of astrocytic and striated muscle cell components in these tumours. Although the number of reported cases is limited they appear to have a better prognosis than the conventional form of adult medulloblastoma. It seems therefore that the term lipidized mature neuroectodermal tumour, rather than lipidized medulloblastoma, would be a more appropriate term for these tumours.

Aged↗
PubMed1998

Sarcomatoid carcinoma of the skin: report of a case.

We report the histological, immunohistochemical and ultrastructural findings of an exophytic cutaneous tumor composed of a mixture of typical basal cell carcinoma (BCC) and malignant fibrous histiocytoma. Nine previously reported carcinosarcomas of the skin are reviewed. We prefer the term "sarcomatoid carcinoma" for this rare neoplasm. Only the BCC showed a positive immunoreaction to cytokeratin; the sarcomatous component was negative, but it did express vimentin, and, focally, smooth-muscle-specific actin and KP1 (CD68). Both components showed p53 immunostaining.

Aged↗
PubMed1998

Polythelia pilosa: a particular form of accessory mammary tissue.

BACKGROUND: The old Kajawa classification which considered eight possible forms of aberrant mammary tissue has been recently modified into a simpler one that considers this condition only when there is glandular parenchyma or when the aberrant tissue is not a glandular tissue but a nipple, an areola or both. This new classification disregards 'polythelia pilosa' defined as an 'isolated patch of hairs only'. OBJECTIVE: To demonstrate that polythelia pilosa is at least a marker of subjacent accessory mammary tissue and, consequently, that the term should be incorporated into the current classification. METHODS: Among 72 cases of aberrant or accessory mammary tissue, we have studied 14 cases (7 men and 7 women) that were clinically diagnosed as 'visible isolated patches of hairs, apparently without pigmentation nor structures of areola or nipple'. We excised such isolated patches in 3 women. RESULTS: The histopathological examination showed an acanthotic and hyperpigmented epithelium with central depression closed by keratin plugs; in the dermis there were follicles with hairs surrounded by hypertrophic sebaceous glands. In the deepest portion, abundant secretory glomerules and excretory ducts of apocrine gland type could be observed. CONCLUSION: Since the biopsy of isolated patches of hairs demonstrated structures of either areolar or apocrine glandular tissue, we think that the term 'polythelia pilosa' should be reinstated into the classification as it is at least a marker of true aberrant mammary structures in men and hirsute women.

Adolescent↗
PubMed1998

Blood group antigens in differentiated thyroid neoplasms.

Alteration of cell-surface blood group antigens during malignant transformation is a well-known phenomenon that has not yet been sufficiently investigated in thyroid gland neoplasms. We evaluated 50 normal thyroid glands and 141 differentiated thyroid neoplasms (29 follicular adenomas, 30 follicular carcinomas, 56 papillary carcinomas, and 26 medullary carcinomas) both by the immunoperoxidase technique, using monoclonal antibodies against blood group antigens (A, B, H, Le(a), Le(b), Le(x), and Le(y)) and precursor substances (T, Tn, and sTn), and by affinity to the lectin from Arachis hypogea, to determine the usefulness of these antigens as tumor markers and prognostic factors. Neoplastic tissues showed immunostaining with concordant and nonconcordant expression of ABH antigens. There were statistically significant differences between normal and neoplastic tissues but not among the different neoplasms. Statistically significant differences in Lewis antigen expression were noted between normal and neoplastic tissues and between benign and malignant tumors. Tn and sTn antigen expression showed statistically significant differences between normal and neoplastic tissues. In conclusion, blood group antigens are tumor markers that are expressed more frequently in malignant than in benign neoplasms. The presence of metastases was correlated with enhanced peanut lectin receptors and a loss of A or B antigens.

ABO Blood-Group System↗
PubMed1996

Mandibular lymphomas with sclerosis.

Two cases of non-Hodgkin's lymphoma that show a sarcomatoid pattern within the jaw are described. Their primary origin in bone was demonstrated by radiologic studies. In one case, diagnosis was delayed because the clinical picture suggested inflammatory periodontal disease. In both cases, the histologic picture was similar to that of a sarcomatoid neoplasm with intense stromal sclerosis; hemimandibulectomy was performed in one case. The tumor contained cells with large, irregular, sometimes lobulated nuclei and high mitotic activity, and perforated mandibular bone with infiltration into adjacent soft tissues. The lymphoid nature of these neoplasms was demonstrated by immunohistochemical and ultrastructural study.

Humans↗