Penetration of meropenem in lung, bronchial mucosa, and pleural tissues.

Lung, bronchial mucosa, and pleural tissue samples were obtained from 14 patients undergoing lung surgery 1 to 5 h after administration of 1 g of meropenem. The mean (range) peak concentrations of meropenem were 3.9 (0.2 to 8.2), 6.6 (3.0 to 13.3), and 2.8 (0.6 to 7.8) mg/kg of tissue, respectively, exceeding the MICs at which 90% of isolates are inhibited for most respiratory pathogens.

Subrenal capsule assay for fresh human tumors in immunocompetent mice; an inappropriate technique for non-small cell lung cancer.

The subrenal capsule assay (SRA) seems to present some difficulties for the evaluation of the chemosensitivity of antineoplastic agents against fresh tumor xenografts. A study was therefore carried out to verify whether two different xenografts would behave in a similar way. Tumors such as melanoma provided adequate homogeneous material for this technique, while non-small cell lung carcinoma (NSCLC) were heterogeneous since the 1 mm3 specimen grafted under the renal capsule usually contained diffuse areas of necrosis and of infection. Furthermore, a large proportion of the grafted specimens, 257 out of 298, did not contain any tumor at all on microscopic examination even when they showed macroscopic growth. Added to these discrepancies, a random microscopic analysis of 180 adjacent fragments of NSCLC and melanomas demonstrated that the variability of heterogeneous tumors precludes any meaningful comparison between homologous tumor tissues designed to be grafted on treated and on control mice. The anti-inflammatory effect of chemotherapeutic drugs on the host's reaction to the graft is probably responsible for the differences between the macroscopic growth results observed in pieces grafted to both treated and control mice: however, it could not be simulated by hydrocortisone (HC) under our experimental conditions. This allows us to conclude that fresh tumors from NSCLC cannot be used in SRA.