Harmonization and StandardisationWithin the consortium samples will be exchanged for research. The followed path so
far is that the participants come together and determine and agree upon what
samples they need for their experiments. The following set of recommendations has
been determined from these processes:
Recommendations:In case retrospective samples are considered the question need to be asked if
collection differences between institutes will be of influence on the outcome of the
experiment. Are all the samples fit for purpose? Is the data collected sufficient in all
the collections and is it exchangeable in its current format or is data conversion
needed. Is it perhaps better to start a prospective collection from scratch?
For prospective collections differences in protocols can be eliminated with good
agreements. Site visits and external quality control organized between the
participants can further eliminate differences in interpretation of the agreed protocols.
Also here fit for purpose is the question for data (minimal dataset and annotation) as
well as sample (quality and compartment).
Fit for purpose raises many questions for the collection procedures to choose.
Blood samples might look easy to collect, however the choices in the blood
compartment to store (whole blood, buffy coat, serum etc etc.) and the overwhelming
amount of different protocols makes the issue complex again.
Tissue collections enjoy less choice in protocols. An often overlooked cause of bias
in tissue collections are sampling errors due to tissue heterogeneity. Therefore, the
conservation of the proper morphology to determine the histology should always be
an issue when storing tissues. Hence the snap freezing (pre-cooled isopenthane)
method in frozen samples.
In addition, the percentage of cells contributing to the diagnosis (determined by a
pathologist) should outnumber the contribution of other cells preferably by more than
70%. If not, a technique like micro dissection should be considered to enrich this
Description of different methods for collecting samples can be found in:
Recommendations on Common minimalTechnical Standards.
IARC/WHO, Lyon - Caboux, E., Plymoth, A., Hainaut, P. (Eds.), 2007. International
Network of Biological Resource Centres for Cancer Research:
Newly developed methods for blood and tissue sampling (PAX gene) can be found at
the SPIDIA web site.
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