Dr Boudewijn Braakhuis from the University Medical Centre, Amsterdam, The Netherlands, advised that improvements in therapy are desperately needed for this field, because only 40 50% of patients currently survive five years. "Biomarkers," said Dr Braakhuis, "are essential to develop new targeted treatments and improve survival through personalised therapy".
Potential biomarkers for head and neck cancers include loss of heterozygosity (LOH) and TP53 mutations. Furthermore, high EGFR expression and the emergence of skin rash are also believed to be predictive markers of cetuximab efficacy.
"Validation of putative biomarkers in clinical trials should now be mandatory." said Dr Braakhuis. “But the idea of ‘one-mutation-one-treatment’ is probably too simplistic. Information on all possible gene alterations in a given pathway and parallel pathways is likely to be needed to predict responses to a targeted therapy,” she said.
Optimisation of drug prescriptions for head and neck cancers were considered by Dr Lillian Siu from the Princess Margaret Hospital, Toronto, Ontario, Canada.
Current treatments include sequential therapy (induction chemotherapy and concurrent chemo- radiotherapy), chemo-additive (adding another agent to standard chemotherapy), chemo- sparing (using another agent to replace or reduce chemotherapy), and radio-sparing (using an alternative treatment to reduce radiation doses).
There is a need to achieve a balance between preserving high cure rates while reducing acute and late toxicities. “We need to understand the biology of head and neck cancers so that patients who relapse despite having low risk can be identified early,” said Dr Siu. Research, she added, should be targeted at primary and acquired resistance mechanisms.
Professor Jordi Giralt, from Vall d’Hebron University Hospital, Barcelona, Spain, advised that dose painting is a new strategy that can be used for optimal dose intensification. The technology involves the integration of multimodal imaging to optimise target volumes and prescription doses in head and neck cancers.
The value, said Professor Giralt, is reductions in toxicity that should deliver quality of life advantages, including recovery of saliva flow and improvements in swallowing.
Controlled trials have shown dose painting to be feasible, with clinical trials now required to validate this strategy. Such approaches, said Professor Giralt, should pave the way for more effective and individualised treatments in head and neck cancers.