No abstract

It is assumed that detoxification enzymes are functionally redundant and only the simultaneous deficiency of several detoxification enzymes increase the risk for HNSCC in alcohol- and tobacco-exposed individuals.

The prodrug bivatuzumab mertansine (BIWI 1) is a novel CD44v6-targeting humanized monoclonal antibody coupled to the toxin mertansine. In a phase I dose escalation trial 31 patients with squamous cell carcinomas of the head and neck were treated with doses of 25-325 mg/m 2 as a 30-min infusion. Thirteen patients received a second infusion after 3 weeks. Serial serum samples were collected to determine the pharmacokinetic parameters of the prodrug BIWI 1 and of deconjugated BIWI 1 as well as the occurrence of anti-BIWI 1 antibodies. The maximum tolerated dose was reached at 300 mg/m 2 attributable to skin toxicity. No immune response was observed in any patient. For BIWI 1 and deconjugated BIWI 1, clearance values were low and distribution was limited resulting in half-lives of ~3-3.5 days and ~6-7 days, respectively, for single and repeated dosing after three weeks. Overall, interindividual variability of the pharmacokinetic parameters was low. In general, the pharmacokinetics of both compounds after single and repeated dosing was comparable across the entire dose range and no significant accumulation took place. Over the dose range investigated, a dose proportional increase in the exposure of BIWI 1 and deconjugated BIWI 1 was observed. Dose individualization according to body size (weight or body surface area) was found to be appropriate and is recommended for the novel immunoconjugate.

BAC in concentrations used in nasal preparations is ciliotoxic. In healthy individuals, the ciliotoxic effect of BAC is neutralized, probably by components of nasal secretions. No BAC-related proinflammatory effects have been observed. At higher doses than normally used therapeutically, BAC caused significant nasal irritation.

Carcinosarcomas of the urinary bladder are malignant biphasic tumors with an epithelial and a spindle cell component. For the histogenesis of the two components, a biclonal and a monoclonal origin are discussed. We present the immunomorphology and molecular cytogenetics of such a case. The immunohistology of biopsies of the urinary bladder revealed a poorly differentiated urothelial carcinoma (GIII) and a co-existing pleomorphic, spindle cell leiomyosarcoma (GIII). The two components were microdissected and further analyzed for gains and losses of chromosomal material using comparative genomic hybridization. In addition, loss of heterozygosity analyses were included. The tumor components revealed as overlapping core aberrations losses on the short arm of chromosome 9 and on the long arm of chromosome 11. However, both components showed additional aberrations exclusively detected in one of the components. The occurrence of overlapping aberrations strongly argues for a monoclonal origin of this tumor with a common ancestor. The additional aberrations of the components point to an independent and divergent course of tumor progression in both components.