[Docetaxel and gemcitabine combination in soft-tissue sarcomas treatment]. / Association gemcitabine et docetaxel dans le traitement des sarcomes des tissus mous.

Soft-tissue sarcomas (STS) are usually sensitive to doxorubicine and/or ifosfamide. When tumors become refractory to these two drugs, chemotherapeutic options are limited. All the drugs tested generally yield occasional or negligible response, with response rates lower than 20% and a poor duration of response. No second-line chemotherapy have been clearly adopted. In vitro synergistic cytotoxicity has been reported with gemcitabine and docetaxel combination. Promising anti-tumor activity has been described with gemcitabine alone, docetaxel alone or these two drugs in combination These treatments were generally well tolerated. The best response have been observed in leiomyosarcomas. According to these results, gemcitabine and docetaxel combination might be of interest in STS. However, a phase III study is required to better evaluate the real advantage of this treatment.

Magnetic resonance imaging measurements of vascular permeability and extracellular volume fraction of breast tumors by dynamic Gd-DTPA-enhanced relaxometry.

Vascular permeability (k(ep), min(-1)) and extracellular volume fraction (v(e)) are tissue parameters of great interest to characterize malignant tumor lesions. Indeed, it is well known that tumors with high blood supply better respond to therapy than poorly vascularized tumors, and tumors with large extracellular volume tend to be more malignant than tumors showing lower extracellular volume. Furthermore, the transport of therapeutic agents depends on both extracellular volume fraction and vessel permeability. Thus, before treatment, these tissue parameters may prove useful to evaluate tumor aggressiveness and to predict responsiveness to therapy and variations during cytotoxic therapies could allow to assess treatment efficacy and early modified therapy schedules in case of poor responsiveness. As a consequence, there is a need to develop methods that could be routinely used to determine these tissue parameters. In this work, blood-tissue permeability and extracellular volume fraction information were derived from magnetic resonance imaging dynamic longitudinal relaxation rate (R(1)) mapping obtained after an intravenous bolus injection of Gd-DTPA in a group of 92 female patients with breast lesions, 68 of these being histologically proven to be with carcinoma. For the sake of comparison, 24 benign lesions were studied. The measurement protocol based on two-dimensional gradient echo sequences and a monoexponential plasma kinetic model was that validated in the occasion of previous animal experiments. As a consequence of neoangiogenesis, results showed a higher permeability in malignant than in benign lesions, whereas the extracellular volume fraction value did not allow any discrimination between benign and malignant lesions. The method, which can be easily implemented whatever the imaging system used, could advantageously be used to quantify lesion parameters (k(ep) and v(e)) in routine clinical imaging. Because of its large reproducibility, the method could be useful for intersite comparisons and follow-up studies.