Biomedical subjects

C Veiras

Publications and source records attributed to C Veiras.

6 recordsLinked to original sources

PubMed2003

Infrastructure of radiotherapy in Spain: a minimal standard of radiotherapy resources.

PURPOSE: To assess the state of our specialty, the Spanish Society of Radiotherapy and Oncology ordered a survey of all Spanish services of radiation oncology. METHODS AND MATERIALS: In June 1999, the Society ordered an analysis of the state of radiation oncology. It created a survey that was sent to all radiotherapy units in Spain. A database was created in which 230 variables were analyzed. RESULTS: Eighty-four centers were analyzed, and 157 external beam irradiation, megavoltage units were counted, of which 67 were cobalt units and 90 were linear accelerators. The cobalt units worked an average of 11.4 h daily and the linear accelerators 11.6 h. The number of patients/unit/y was 472 for the cobalt units and 442 for the linear accelerators. The number of patients by physician and year was 179. Each center received a mean of 958 new patients annually. The average between the reception and start of treatment was 25.52 days (maximum 60), and it was estimated that only 38.1% of cancers were irradiated. The number of radiation oncologists working was 392. Spain has a deficit of 297 radiation oncologists. CONCLUSION: There is a need for 44 MV units and for the replacement of 67 cobalt units. The present lack of units has had an impact on palliative treatment, which has resulted in pharmacy costs. As long as these instrumental deficiencies are not solved, waiting lists will continue to be inherent to the system. There are also important staff deficiencies, in that about 297 radiation oncologists would be needed to cover the needs.

Health Services Needs and Demand↗

PubMed1999

Phase II study of radiochemotherapy with UFT and low-dose oral leucovorin in patients with unresectable rectal cancer.

PURPOSE: To determine the activity and evaluate the toxicity of uracil and tegafur in a 4:1 molar concentration (UFT) plus low-dose leucovorin administered concomitantly with pelvic irradiation in patients with unresectable or recurrent rectal cancer. METHODS AND MATERIALS: Thirty-five patients (22 with primary unresectable tumors and 13 with locally recurrent tumors) were enrolled in the trial. Thirty-five patients were evaluable for toxicity and 32 of these were evaluable for clinical response. Patients received 300 mg/m2/day UFT and 30 mg/day leucovorin on days 8-35 concomitantly with pelvic radiotherapy, to a total dose of 45 Gy. RESULTS: Eight of the 35 (23%) patients developed Grade 3 diarrhea and were treated with radiotherapy alone after this event. Of the 22 patients with unresectable primary tumors, 17 underwent surgery, and resection was feasible in 15 cases (88%). Of the 32 patients evaluable for clinical response, 4 (13%) had a complete clinical response (CR) and 22 (69%) a partial response (PR). A complete pathologic response was observed in 3 cases (18%) and, a PR in 11 cases (65%). CONCLUSION: The response rates achieved with this schedule seem comparable to those obtained with 5-FU and radiotherapy. These results warrant further evaluation of this combination in patients with unresectable or locally advanced tumors.

Adult↗

PubMed1995

X-ray biological dosimetry performed by selective painting of human chromosomes 1 and 2.

Fluorescence in situ hybridization with a cocktail of whole-chromosome probes, specific for human chromosomes 1 and 2, was performed to analyze the induction of translocations and dicentrics in human peripheral blood lymphocytes exposed to 100 KVp X-rays and cultured for 48 h. The dose-response curves for both aberration types were linear-quadratic, with similar coefficients, and after correction for genome content were a little lower than the dose-response curve for dicentrics established by conventional analysis. Three doses were also assessed after 76-h culture. The dicentric yield at 76 h was reduced compared with that at 48 h because of the existence of second and third division metaphases. The translocation yield did not reduce except at 4 Gy. The frequency of cells containing both dicentrics and translocations suggested that their occurrence is not correlated. The importance of stating the scoring criteria and of specifying the different types of aberrations is stressed.

Cells, Cultured↗

PubMed1985

Persistence of DNA lesions and the cytological cancellation of sister chromatid exchanges.

The ability of UV light, mitomycin C and ionizing radiation to induce the formation of sister chromatid exchanges (SCEs) at the same locus in successive cell generations was investigated in human lymphocytes. Cells were exposed to the DNA damaging agents after they had completed their first round of DNA replication, and SCEs were examined at the third division in chromosomes that had been differentially stained three ways. Although some of these treatments induced long-lived lesions that increased the frequency of SCEs in successive cell generations, none of the lesions led to the formation of consecutive SCEs at the same locus in successive cell generations. This observation seriously challenges the hypothesis that SCE cancellation results as a consequence of persistence of the lesions induced by these agents.

Antibiotics, Antineoplastic↗

PubMed1983

[Enzymatic changes in cancer].

Several enzymes were estimated in different tumors. Ceruloplasmin, lactate dehydrogenase (LDH), and phosphohexose isomerase (PHI) showed a direct correlation with tumor growth and remission. The ratio LDH/PHI was low in solid tumors and high in lymphomas, suggesting a different metabolism.

Ceruloplasmin↗

PubMedDate not supplied

[Radiotherapy in glottic T1 carcinoma. Local control and survival].

Between January 1980 and April 1995, 57 treatment-naive patients diagnosed as glottic epidermoid T1 carcinoma were treated in the ear, nose and throat department of Juan Canalejo Hospital of La Coruña, Spain. Seventy-nine percent (79%) (45/57) had T1a lesions and 21% (12/57) had T1b. All patients were treated by the radiotherapy department of the Regional Oncological Center with Co60 at doses ranging from 50 Gy to 70 Gy. Local control was achieved in 74.5% (43/57). Cause-specific survival was 96% at 3, 5, and 10 years. The larynx was preserved in 96.5% (55/57). The local recurrence rate was significantly lower for T1a (16.8%) than for T1b (57.8%) (p < 0.05). No significant differences were found in local control or survival with different dosing regimens.

Adult↗