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Increasingly, targeted oral-dose anti-cancer drugs like Tarceva and Iressa are found to treat cancers effectively in those that it is helping, and seen as an intergral and necessary part of a patient's cancer care.

Tarceva and Iressa are very similar drugs, small molecule inhibitors of tyrosine kniase, a key intermediary in the EGF cascade pathway. Drugs that inhibit Epidermal Growth Factor Receptor (EGFR inhibitor). EGF-targeted drugs are poorly-predicted by measuring the ostensible target (EGFR), but can be well-predicted by measuring the effect of the drugs on the function of 'live"cells. It is an area of cancer research which has been abandoned by most of the cancer research establishment, except for a conscientious band of cell biologists.

Oncologists prescribe patients one standard empiric chemotherapy regimen after another, until they find one that works. This often can expose patients to the side effects of chemotherapy, without showing any cancer-killing results. Guesswork can be done in a laboratory instead. The tactic of using biopsied cells to predict which cancer treatments will work best for the patient, by taking pieces of tumor tissue, apply different chemotherapy treatments to it and examine the results to see which drug or combination of drugs do the best job killing the tumor cells.

A new laboratory test has accurately identified patients who would benefit from treatment with the molecularly-targeted anti-cancer therapies Tarceva and Iressa. This could help solve the problem of knowing which patients can tolerate costly, new treatments and their harmful side-effects. These "smart" drugs do not work for everyone, and a test to determine the efficacy of these drugs in a patient could be the first crucial step in personalizing treatment to the individual.

By inhibiting anti-apoptosis with Tarceva or Iressa, the cells undergo apoptosis and die. And it is detected at the whole cell level in the cell culture assays and reported out -- prospectively -- that this correlates strikingly with patient survival. The new test predicted accurately for the survival of patients treated with the targeted drugs.

The new test relies upon what is called "functional profiling," in which living tumor cells are removed from an individual cancer patient and exposed in the laboratory to the new drugs. A variety of metabolic and apoptotic measurements are then used to determine if a specific drug was successful at killing the patient's cancer cells. The "functional profiling" method assesses the activity of a drug upon combined effect of all cellular processes, using combined metabolic and morphologic endpoints, at the cell "population" level (rather than at the single-cell level), measuring the interaction of the entire genome.

The "functional profiling" method makes the statistically significant association between prospectively reported test results and patient survival. Using the EGFRx Assay with "functional profiling" can correlate test results which are obtained in the lab and reported to physicians prior to patient treatment, with significantly longer or shorter overall patient survival depending upon whether the drug was found to be effective or ineffective at killing the patient's tumor cells in the laboratory.

Tarceva and Iressa have been shown to benefit those that are benefitting from it. If the drugs are working for some people, then obviously there are others out there who would also benefit. Who are those that would benefit from its use? All the more reason to test the tumor first.