Cancer and the environment: the American Cancer Society prevention priorities

Comparison of pemetrexed and docetaxel as salvage chemotherapy for the treatment for nonsmall-cell lung cancer after the failure of epidermal growth factor receptor-tyrosine kinase inhibitors

OBJECTIVE

To compare the therapeutic effects and adverse reactions of pemetrexed and docetaxel as salvage chemotherapy in patients with nonsmall-cell lung cancer (NSCLC) after the failure of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI).

METHODS

In this randomized Phase 2 trial, patients with NSCLC who had previously failed EGFR-TKI therapy were randomized to receive intravenous pemetrexed (500 mg/m(2) for 21 days [one cycle]) or docetaxel (75 mg/m(2) for 21 days [one cycle]). Therapeutic effects were evaluated according to Response Evaluation Criteria in Solid Tumours standards and adverse effects were evaluated according to the US National Cancer Institute Common Terminology Criteria for Adverse Events.

RESULTS

There was no statistically significant difference in disease control rate, response rate, median survival and 1-year survival between treatment groups. Rates of nausea, myelosuppression, renal damage and hair loss were significantly higher in the docetaxel group than the pemetrexed group.

CONCLUSION

Pemetrexed is effective and well tolerated as salvage chemotherapy in patients with NSCLC after EGFR-TKI failure and may be a suitable therapeutic option in these patients.

Cancer and environment: definitions and misconceptions

BACKGROUND

Scientific evidence supports an association between environmental exposures and cancer. However, a reliable estimate for the proportion of cancers attributable to environmental factors is currently unavailable. This may be related to the varying definitions of the term "environment." The current review aims to determine how the reporting of the definition of the environment and of the estimates of environmentally attributable risks have changed over the past 50 years.

METHODS

A systematic literature search was performed to retrieve all relevant publications relating to the environment and cancer from January 1960 to December 2010 using PubMed, EMBASE, Scopus, and Web of Science. Definitions of the environment and environmentally attributable risks for cancer were extracted from each relevant publication.

RESULTS

The search resulted in 261 relevant publications. We found vast discrepancies in the definition of the environment, ranging from broad (including lifestyle factors, occupational exposures, pollutants, and other non-genetic factors) to narrow (including air, water, and soil pollutants). Reported environmentally attributable risk estimates ranged from 1% to 100%.

CONCLUSIONS

Our findings emphasize the discrepancies in reporting environmental causation of cancer and the limits of inference in interpreting environmentally attributable risk estimates. Rather than achieving consensus on a single definition for the environment, we suggest the focus be on achieving transparency for any environmentally attributable risks.