Malignant mesothelioma

Malignant mesothelioma (MM) is an aggressive tumour that commonly affects the mesothelial surfaces of the pleural and peritoneal cavities, and occasionally, the tunica vaginalis and the pericardium. Formerly a rare tumour, MM is increasing in incidence in Australia due to the heavy nationwide use of asbestos from 1940 until the 1980s. The incidence is expected to peak in Australia in the next decade, mirroring the long latency period between asbestos exposure and development of MM. Diagnosis of MM can be difficult. Definitive pathological diagnosis is required and it often requires an experienced pathologist to differentiate MM from other benign or malignant processes. Treatment of MM requires a multidisciplinary approach, regardless of palliative or curative intent. Treatment options, such as surgery, chemotherapy, radiotherapy and active symptom control or a combination of these, may be used. Further research is needed to advance the therapeutic options for MM, and strategies to realize personalisation of therapy through discovery of predictive markers. In the Australian society where asbestos contamination of the built environment is very high, education and stringent public health measures are required to prevent a second wave of increased MM incidence.

Cardiovascular toxicity profiles of vascular-disrupting agents

BACKGROUND

Vascular-disrupting agents (VDAs) represent a new class of chemotherapeutic agent that targets the existing vasculature in solid tumors. Preclinical and early-phase trials have demonstrated the promising therapeutic benefits of VDAs but have also uncovered a distinctive toxicity profile highlighted by cardiovascular events.

METHODS

We reviewed all preclinical and prospective phase I-III clinical trials published up to August 2010 in MEDLINE and the American Association of Cancer Research and American Society of Clinical Oncology meeting abstracts of small-molecule VDAs, including combretastatin A4 phosphate (CA4P), combretastatin A1 phosphate (CA1P), MPC-6827, ZD6126, AVE8062, and ASA404.

RESULTS

Phase I and II studies of CA1P, ASA404, MPC-6827, and CA4P all reported cardiovascular toxicities, with the most common cardiac events being National Cancer Institute Common Toxicity Criteria (version 3) grade 1-3 hypertension, tachyarrhythmias and bradyarrhythmias, atrial fibrillation, and myocardial infarction. Cardiac events were dose-limiting toxicities in phase I trials with VDA monotherapy and combination therapy.

CONCLUSIONS

Early-phase trials of VDAs have revealed a cardiovascular toxicity profile similar to that of their vascular-targeting counterparts, the angiogenesis inhibitors. As these agents are added to the mainstream chemotherapeutic arsenal, careful identification of baseline cardiovascular risk factors would seem to be a prudent strategy. Close collaboration with cardiology colleagues for early indicators of serious cardiac adverse events will likely minimize toxicity while optimizing the therapeutic potential of VDAs and ultimately enhancing patient outcomes.