1 INTRODUCTION
Phytochemicals have exhibited great potential in prevention & treatment of HNC. Use of biomarker to identify patients, which are better suited for chemoprevention can lead to huge advancement in chemo preventive research. To develop a broad range of targeted therapeutics, understanding the different molecular pathways associated with HNC oncogenesis is very important. Genetic alterations in body fluids, tumor tissue and serum could be used for early detection and treatment of HNC.
Current common treatment modalities for HNC are surgery, radiotherapy, and chemotherapy. Although recent advances in cancer imaging (Magnetic Resonance Imaging [MRI], Positron emission tomography [PET], Computer Tomography [CT)] and computer software treatment plan have benefitted the radiation delivery technology, yet non specificity and toxicity to normal cells result in low response rates. From the last few decades, to reduce treatment related toxicity and to increase patient survival, combination of two or more phytochemicals or phytochemical with radio/chemotherapy at lower doses has come up as a promising therapeutic approach. The main aim supporting this combinatorial approach is, reduction of adverse side effect by other therapies and increase the anticancer efficacy at lower doses.
Recently some clinical trials using numerous combinations of phytochemicals with standard chemotherapeutic drugs and radiation have been done to assess the therapeutic potential of phytochemicals as adjunct for prevention and treatment of HNC patients (Duarte et al. , 2010 Leoncini et al. , 2015 Shrotriya et al. , 2015).
Therefore current study reviews the role of phytochemicals in HNC pathogenesis, management and treatment and discusses the ability of these phytochemicals to act as adjuvants along with existing HNC therapies. Further individual phytochemicals, their synthetic analogues /nano formulations already under preclinical and clinical studies and the challenges faced in their translation from bench to bedside are also discussed.