In May of this year, two major scientific journals published papers correlating response to Iressa, AstraZeneca's targeted therapy for refractory non-small cell lung cancer, to a series of mutations clustered in a section of the EGFR gene. These widely publicized findings are fueling discussions that are bound to have consequences not only for AstraZeneca, patients and clinicians, but also for many pharmaceutical companies working on targeted therapies.

A Lancet paper published two years ago detailing a promising but highly novel approach to detecting ovarian cancer, one of the deadliest cancers, continues to be the subject of great controversy in cancer circles. The test uses proteomic pattern profiling to detect the cancer, with a more than 95% accuracy in early studies, but no one knows what the patterns are made of. The NCI and two large reference labs are pushing ahead to get the test into the clinic, on the premise that as long as it is so good at detecting cancer, a lack of understanding of the underlying biochemistry isn't an insurmountable hurdle to acceptance.

Exact Sciences and its distribution partner, LabCorp are on the verge of launching a new molecular test for colon cancer screening. They've taken deal-making in diagnostics to a new level, but now they have to deliver on their promises.