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Old 05-16-2013, 03:21 PM   #25
gdpawel
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Join Date: Aug 2006
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Re: Tumor Profiling Lab Tests

The choice of a lab is not a geographical consideration, but a technical consideration. All of the labs are experienced and capable of providing very useful information.

However, the labs vary considerably with regard to technologies, approach to testing, what they try to achieve with the testing, and cost. Some labs have been offering these assays as a non-investigational, paid service to cancer patients, in a situation where up to 30 different drugs and combinations are tested, at two drug concentrations in three different assay systems.

The labs will provide you and your physician with in depth information and research on the testing they provide. Absent the assays, the oncologist will perform "trial-and-error" treatment until he/she finds the right chemotherapy regimen. You should have the right chemo in the first-line of treatment.

By investing a little time on the phone speaking with the lab directors, you should have enough knowledge to present the concept to your own physician. At that point, the best thing is to ask the physician, as a courtesy to the patient, to speak on the phone with the director of the laboratory in which you are interested, so that everyone (patient, physician, and laboratory director) understand what is being considered, what is the rationale, and what are the data which support what is being considered.

Also, there is tumor analysis (genotyping) coupled with clinical trial literature search, which tries to match therapies to patient-specific biomarker information to generate a treatment approach. In other words, information that may help when considering "potential" treatment options (theoretical analysis).

Or you can "actually" measure (phenotyping) the response of the tumor cells to drug exposure. Following this exposure, measure both cell metabolism and cell morphology. The integrated effect of the drugs on the whole cell, resulting in a cellular response to the drug, measuring the interaction of the entire genome.

The endpoints (point of termination) of genotyping analysis are gene express, examining a single process (pathway) within the cell or a relatively small number of processes (pathways) to test for "theoretical" candidates for targeted therapy.

The endpoints of phenotyping analysis are expression of cell-death, both tumor cell death and tumor associated endothelial (capillary) cell death (tumor and vascular death), and examines not only for the presence of the molecular profile but also for their functionality, for their interaction with other genes, proteins and other processes occuring within the cell, and for their "actual" response to targeted therapy (not theoretical susceptibility).

Again, the choice is theoretical vs actual analysis.

World renowned Oncologists are challenging the cancer industry to recognize a Chemo-Screening test (CSRA) that takes the "guesswork" out of drug selection. One of the reasons medical oncologists don’t like in vitro chemosensitivity tests is that it may be in direct competition with the randomized controlled clinical trial paradigm. http://vimeo.com/72389724
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