Biomedical subjects

E Bessa

Publications and source records attributed to E Bessa.

8 recordsLinked to original sources

PubMed2001

[Double-blinded controlled study comparing clodronate versus placebo in patients with breast cancer bone metastases].

One hundred forty-four patients with breast cancer and osteolytic bone metastases were randomized to receive either oral clodronate 1,600 mg/d (73 patients) or placebo (71 patients), in addition to either chemotherapy or hormonal therapy, for up to 12 months. Patients were withdrawn from the study when the 12 months of treatment had been achieve or a new bone event occurred, which was defined as: hypercalcemia (> 3 mmol/l), increase in, or onset of new bone pain due to metastases, requirement of radiotherapy for bone pain relief, pathological fractures (including vertebral collapse, spinal cord compression) or death due to bone metastases. Patients are well balanced according to age, performance status, bone condition, except for fractures, more frequent in the clodronate group (25% vs 12%). Of the 137 evaluable patients, 69 received oral clodronate and 68 placebo. Clodronate significantly delayed the median time to onset of new bone events compared to placebo, respectively 244 days and 180 days (p = 0.05). Hypercalcemia did not occur in the clodronate group but was observed in four placebo-treated patients. Clodronate-treated patients had a significant reduction in pain intensity compared to placebo (p = 0.01; measured using a visual pain scale) and significantly fewer patients receiving clodronate required analgesics (p = 0.02). The evaluation of global efficacy by physicians and patients indicated that clodronate was more efficacious than placebo (respectively p = 0.02 and p = 0.01). No significant difference in incidence of adverse effects was observed between the two groups. Clodronate therapy significantly delayed the occurrence of new bone events in these patients with bone metastases from breast cancer and adds to treatment of malignant osteolysis.

Administration, Oral↗

PubMed1998

Radiation dose, chemotherapy and risk of osteosarcoma after solid tumours during childhood.

Osteosarcoma is the most frequent second primary cancer occurring during the first 20 years following treatment for a solid cancer in childhood. Using a cohort study of children treated for a solid cancer, we investigated the incidence and etiology of osteosarcoma as a second malignant neoplasm after childhood cancer in a cohort and a case-control study. We analysed the relationship between the local dose of radiation and the risk of osteosarcoma, taking into account chemotherapy received. A cohort study of 4,400 3-year survivors of a first solid cancer during childhood diagnosed in France or the United Kingdom, between 1942 and 1986, revealed 32 subsequent osteosarcomas. In a nested case-control study, we matched 32 cases and 160 controls for sex, type of first cancer, age at first cancer and the duration of follow-up. Parameters studied were the incidence of osteosarcoma, the cumulative local dose of irradiation and the cumulative dose of chemotherapy received by cases and controls. The risk of a osteosarcoma was found to be a linear function of the local dose of radiation (excess relative risk per gray=1.8), and was found to increase with the number of moles of electrophilic agents per square meter but not with other drugs. No interaction was noted between radiotherapy and chemotherapy. Bilateral retinoblastoma, Ewing's sarcoma and soft tissue sarcoma were found to render patients susceptible to a higher risk of developing an osteosarcoma as a second malignant neoplasm. We recommend long-term surveillance of patients who were treated during childhood for bilateral retinoblastoma, Ewing's sarcoma, soft tissue sarcoma, as well as other first cancer treated with radiotherapy plus high doses of chemotherapy, without focusing exclusively on the radiation field.

Adolescent↗

PubMed1997

Pharmacokinetics and distribution of 6-mercaptopurine administered intravenously in children with lymphoblastic leukaemia.

OBJECTIVE: The pharmacokinetics of 6-mercaptopurine, including cerebrospinal-fluid (CSF) distribution, and the erythrocyte 6-thioguanine nucleotide concentrations were determined in children randomised to receive intravenous mercaptopurine for acute lymphoblastic leukaemia (ALL), according to the EORTC protocol ALL n.58881. RESULTS: After 1 month of oral treatment at a dose of 50 mg.m-2.day-1, the pharmacokinetic parameters were determined after the first i.v. administration of 1 g.m-2 (bolus dose of 0.2 g.m-2 followed by an 8-h infusion of 0.8 g.m-2) in 11 patients: systemic clearance was 23.02 1.h-1, volume of distribution was 0.75 l.kg-1, and elimination half-life was 1.64 h. The erythrocyte thioguanine concentrations were measured in the same 11 patients and increased significantly between the beginning and the end of infusion (10 pmol x 10(8) packed RBC) or within 24 h of infusion (223 pmol x 10(8) packed RBC). The CSF concentration was 3.78 mumol.1(-1), 1-6 h after the beginning of infusion (n = 28) and the CSF to plasma ratio was 0.15 (n = 16). In patients receiving the oral dose of 50-165 mg.m-2.day-1 of 6-mercaptopurine, CSF concentrations were below 0.18 mumol.1(-1), 1-24 h after drug intake (n = 67), and the CSF to plasma ratio was not calculated. CONCLUSION: Following the i.v. administration of 6-mercaptopurine, we observed high CSF concentrations of 6-mercaptopurine and an acute increase of erythrocyte thioguanine nucleotide concentrations. The clinical trial (EORTC protocol ALL n[symbol: see text]5881), comparing the oral and i.v. administrations of mercaptopurine, will demonstrate if the i.v. administration reduces the incidence of CNS relapses.

Adolescent↗

PubMed1997

Effectiveness of cold cap in the prevention of docetaxel-induced alopecia.

Docetaxel is a new taxoid antineoplastic agent with clinical efficacy especially in breast cancer. One of the most distressing side-effects induced by docetaxel is alopecia. We studied the prevention of alopecia by using a cold cap in 98 patients receiving 100 mg/m2 docetaxel by 1 h i.v. infusion every 3 weeks. One patient was lost to follow-up. 83 patients (86%) were evaluated as a success to the cold cap, as they presented WHO grade alopecia < or = 2 and no need to wear a wig. 14 patients (14%) had to wear a wig; among them; 7 patients withdrew before the evaluation at three cycles. The cold cap is a very effective technique with minimal side-effects for docetaxel-treated patients.

Adult↗

PubMed1996

Cerebrospinal fluid examination in a case of childhood orbital granulocytic sarcoma.

The diagnosis of a case of childhood orbital granulocytic sarcoma, initially classified as a poorly-differentiated malignant tumor, was finally considered at the time of relapse following primary treatment with chemotherapy and local irradiation. At this time, systematic cerebrospinal fluid examination showed numerous blast cells with Auer rods, consistent with the diagnosis of meningeal acute myeloid leukemia of M2 type, and concomitant biopsy of the tumor indicated the diagnosis of chloroma. Reevaluation of the primary biopsy confirmed this diagnosis.

Biopsy↗

PubMed1995

Solid malignant neoplasms after childhood irradiation: decrease of the relative risk with time after irradiation.

The pattern of the temporal distribution of solid cancer incidence after irradiation in childhood is not well known, although, its importance in radioprotection is well known. We studied a cohort of 1,055 children from 8 European cancer centres, who received radiotherapy between 1942 and 1985 for a first cancer in childhood. After a mean follow-up of 19 years, 26 children developed a solid second malignant neoplasm (SMN), as compared to 5.6 expected from general population rates. Both the excess relative risk and the excess of absolute risk of solid SMN were higher among children who were younger at time of the irradiation. After reaching a maximum 15 to 20 years after irradiation, the excess relative risk of SMN decreased with time after irradiation, when controlling for age at irradiation and sex. The analysis of the risk of thyroid, brain and breast cancer together, as a function of the dose averaged on these 3 organs lead to similar results.

Adolescent↗

PubMed1994

Thiopurine methyltransferase activity in a French population: h.p.l.c. assay conditions and effects of drugs and inhibitors.

1. Thiopurine methyltransferase (TPMT) is a cytosolic enzyme involved in the catabolism of thiopurine drugs, which are used to treat cancer patients and organ transplant recipients. Because TPMT activity is polymorphic and under genetic control, large interindividual variations in the immunosuppressive activity and toxicity of these drugs may, at least in part, be inherited. 2. We have developed a specific h.p.l.c. method for measuring 6-methyl mercaptopurine formed from 6-mercaptopurine (6-MP) in red blood cell lysates during the TPMT assay procedure. In blinded assays of 55 samples from adult blood donors, the results of the h.p.l.c. method correlated with those of the radiochemical reference method (r = 0.83, P < 0.001). 3. Using this h.p.l.c. assay, we tested the effect of known inhibitors of TPMT activity (syringic acid, p-anisic acid and tropolone) in vitro and showed that they were highly inhibitory. We also found that drugs often administered concomitantly with 6-MP (prednisone, prednisolone, 6-methylprednisolone, cyclophosphamide, methotrexate, and trimethoprim-sulphamethoxazole) had little or no effect on TPMT activity in vitro. 4. In a group of 300 French individuals, TMPT activity was highly variable, ranging from 4.7 to 35.3 nmol h-1 ml-1 of packed red blood cells (nmol h-1 ml-1 PRBC) with a mean value of 19.3 +/- 4.9. TMPT activity was not influenced by sex. 5. This sensitive and reproducible h.p.l.c. assay for TPMT activity in red blood cells may prove useful for prospective clinical studies designed to optimise dosage regimens of thiopurine drugs (detection limit for 6-methyl mercaptopurine is 5 ng ml-1, intra- and inter-assay variations are 6.8 and 8.2%, respectively).

Adult↗

PubMed1989

[Tolerance and immunogenicity of the capsular polyoside vaccine against Haemophilus influenzae type b. A study of 325 children 15 to 71 months of age].

The antigenic properties of the capsule polyoside (PRP) from Haemophilus influenzae type b (Hib) are adequate to form the basis for immunization designed to prevent the severe infections caused by this organism. The tolerance and immunogenicity of a vaccine containing either 12.5 or 25 micrograms PRP were studied in 325 healthy children aged 15 to 71 months after informed consent had been obtained from the parents. Each child was given one subcutaneous injection of 0.5 ml vaccine. Antibodies against Hib were assayed before and one month after the injection. Clinical tolerance was outstanding both locally (moderate and transient pain in 13% of cases) and systematically, with only eight (2.6%) febrile reactions in excess of 38.5 degrees C within 24 hours after the injection. A very significant rise in antibody titers was seen in all age groups, but a mean titer of 1 microgram/ml was achieved only in children aged 24 months or more. No significant difference was found between the two dosages. Individual analysis showed that following immunization antibody titers reached 0.15 micrograms/ml or more in 65% of infants aged 15 to 17 months, 71% of infants aged 18 to 23 months, 80% of infants aged 24 to 30 months and 95% of children older than 30 months. Despite the inadequate immune response evidenced in the younger age groups, our results confirm that Hib infections are preventable from the age of 2 years. Our results are consistent with those recorded with a similar vaccine in Finland.

Antibody Formation↗