[Prophylactic cranial irradiation in non-small cell lung cancer]. / Irradiation prophylactique cérébrale dans les cancers bronchopulmonaires non à petites cellules.

Prophylactic cranial irradiation (PCI) has become part of the standard treatment in patients with small cell lung cancer (SCLC) in complete remission. Not only does it decrease the risk of brain recurrence by almost 50%, it has a significant positive effect on survival (5.4 percent increase at 3 years). As the prognosis of patients with locally advanced non-small cell lung cancer (NSCLC) has improved with combined modality treatment, brain metastases have also become an important cause of failure (10 to 30%, approaching 50% in certain studies as in SCLC). Survival after treatment of brain metastases is poor and impact on quality of life of patients is important. As in SCLC, 4 randomised evaluating PCI in NSCLC have been carried out in the seventies and early eighties. If 3 out of 4 trials have shown a significant decrease of brain metastases, none of them demonstrated any impact on survival. Thus PCI cannot be recommended as standard treatment in NSCLC, however new trials would be needed.

[The role of radiotherapy in the management of patients with small cell lung cancer]. / Place de la radiothérapie dans la prise en charge des carcinomes bronchiques à petites cellules localisés.

Small cell lung carcinomas are aggressive on account of their high and early risk of dissemination. They represent less than 20% of all lung cancers and only a third of these present with limited stage disease at diagnosis. Currently, treatment is based on synchronous thoracic irradiation and chemotherapy combining platinum salts and etoposide with or without other drugs. Because of the high risk of brain metastases, prophylactic cranial irradiation (PCI) is indicated in patients with a complete response and should be part of the standard management of these patients on the basis of a meta-analysis showing a 5% increase in survival at three years. In limited stage disease 5 year survival rates can reach 25% but the majority of patients will relapse. This progress is the consequence of a better combination of thoracic and cerebral irradiation and polychemotherapy. Even in extensive disease PCI reduces the risk of brain metastases and significantly improves overall survival. Many issues are subject to further clinical research concerning modalities of combination radio-chemotherapy, radiotherapy target volumes, optimum dosage, and the use of drugs in association with irradiation.

[Small cell lung cancer (CPC). Management of patients presenting with limited stage small cell carcinoma of the lung]. / Les cancers à petites cellules. Modalités actuelles de la prise en charge des patients présentant un carcinome bronchique à petites cellules localisé.

Small cell carcinomas represent less than 20% of all lung cancer. Only a third of these patients present with limited stage disease. Treatment is based on a combination of chemotherapy and radiotherapy including a platinum salt with or without another drug. Conformational thoracic radiotherapy is administered either classically fractionated or in an accelerated form. Prophylactic cranial irradiation is indicated in patients with a good response. An improvement in outcomes has been obtained with this regimen. Even in limited stage disease 5 year survival remains about 25% in the best series. The majority of patients will relapse and the risk of cerebral metastases is particularly high, reaching nearly 50% at 2 years even in patients with a complete response. Prophylactic cranial irradiation should be part of the standard management of patients with a complete response on the basis of a meta analysis showing a 5% increase in survival at three years. Even though combination treatments have improved survival, a number of questions remain that should stimulate further clinical trials to establish the optimum regimes of chemotherapy and radiotherapy and the optimum strategies for combining the two. In addition the potential role of targeted therapy in selected patients must be examined.

Affinity purification of a high molecular weight human breast cancer-associated antigen identified by the BCD-B4 monoclonal antibody.

This study reports the purification and characterization of a high molecular weight human breast cancer-associated antigen identified by a previously described (1,2) murine monoclonal antibody, BCD-B4. Immunohistochemical analysis indicated that BCD-B4 recognizes an antigen expressed in an altered form on the human breast carcinoma cell line, BT-20, compared to the non-malignant human mammary epithelial cell line, HBL-100. Chemical treatments and enzymatic digestions suggested that the recognized moiety was a protein. The antigenic determinant was resistant to neuraminidase and periodate treatments but was sensitive to trypsin and proteinase K. The antigen was purified by affinity chromatography and its molecular weight, determined by SDS-PAGE analysis under non-reducing conditions, was proven to be 250 Kd. Under reducing conditions, the molecule dissociated into two polypeptides of 125 and 45 Kd, respectively. Both subunits could be isolated from normal HBL-100 and neoplastic BT-20 cellular protein extracts by affinity chromatography. The higher molecular weight subunit showed; however, qualitative and quantitative differences between the two cell lines: it was expressed in greater quantity on BT-20 cells and its molecular weight was 15 Kd higher. Both subunits could also be identified by immunoblots of BT-20 cells.

E1 glycoprotein of rubella virus carries an epitope that binds a neutralizing antibody.

We identified by immunoprecipitation and Western blot analysis, using a monoclonal antibody that neutralizes rubella virus, that E1 glycoprotein carries an epitope linked with neutralization. Glycosidase treatment of virus does not prevent blotting of this monoclonal antibody with the E1 glycoprotein, dissociating this epitope from the hemagglutination epitope which is linked with the oligosaccharide side chains. We also investigated by Western blot analysis human serum reactivity toward E1 glycoprotein and the two other structural proteins of rubella virus, E2 and C: all positive sera detected E1 and C, irrespective of their titers, indicating the importance of glycoprotein E1 in immunity. Frequent lack of reactivity against E2 might suggest that this glycoprotein is either less exposed or less immunogenic.