Objectives This study aimed to determine the ability to successfully contact past paediatric patients and their families to request participation in research, to assess familial views on the use of previously collected archival clinical samples for research purposes, and to highlight the ethical and practical issues in obtaining this type of retrospective consent.

Methods To assess familial views on the use of such samples for research, we contacted a cohort of families with children previously diagnosed with a brain tumour to ask for consent to an epigenetic/genetic study. Examining participants' responses allowed us to gauge their opinions on the use of such tissue for research, and whether they would like to receive genetic information uncovered during research.

Results We were able to successfully contact 107 out of 178 families and found a significant positive correlation between year of diagnosis and ability to make contact. Of those families contactable that returned a consent form (75/107), 74 agreed to the use of their/their child's archival tissue in future research, and 70 of 74 requested notification should a gene change of potential clinical relevance be found. There were no differences in opinion between parents of living or deceased children or the patients themselves.

Conclusions This study highlights the importance of time since diagnosis on the ability to make contact with previous patients and their families. When contactable, our data highlight the altruistic views of families towards the use of archival clinical samples for research purposes, irrespective of the outcome of their child's illness.