Cancer is the second leading cause of death in the US. Oral cancer has high morbidity and mortality rate if not diagnosed and treated early. The five-year survival rate continues to remain at 50 percent, despite progress in surgery and radiation management.90 Squamous cell carcinoma represents 90% of all malignant tumors.91 Early diagnosis of HNSSC is a challenging process for many clinicians. The asymptomatic nature of the disease is the main limiting factor of early intervention. Primary care physicians and general dentists are the most accessible resource to provide oral health care screening to most Americans. Unfortunately, inconclusive clinical examination of people who suffer from dysphasia or other symptoms related to the head and neck is another limiting factor.92 Screening tests with reliable results are required by health professionals to accurately diagnose HNSSC. The invasive procedure associated with biopsies performed in an attempt to diagnose HNSSC many times makes clinicians and individuals reluctant to consider this option, particularly when early stages of cases still seem harmless.
Clinical evaluations that detect early incidences of cancer provide the opportunity to interfere with and avert cancer progression. The hope is always that unsophisticated, noninvasive, low-priced techniques can be used in the process. The criteria of such screening assays may be found in body secretions, such as saliva, urine, and blood serum.
Searching for a biomarker for early diagnosis of HNSSC remains a challenge. Biomarkers are important molecular hallmarks of the phenotype of a cell that assist in early cancer detection and risk assessment.93 Tumor antigens have been identified for certain specific types of cancer; these antigens play an important role in detecting and diagnosing tumors. Overexpressed antigens may break the immune tolerance threshold. Among 31 sera of lung cancer, two overexpressed proteins were found, namely survivin and livin. Anti-survivin antibodies were detected in 58.1% of 31 sera and anti-livin antibodies in 51.3%.94 Evidence for the presence of an over-immune reaction to overexpressed tumor antigens can be applied to HNSSC. p63 is a homologue of p53 that ∆Np63α is one of the common proteins that appears in the basal layer of the epithelia and functions to preserve originator cell populations in stratified epithelia. 88% of HNSSC subjects have demonstrated overexpressed ∆Np63α.95 Different types of immune assays can be used to detect antibodies.
Indirect ELISA has been widely used in much clinical research. The protocol has neither standardized methods nor specific equipment and is thus a flexible method that allows examiners to develop their own appropriate protocol. The simplicity of the method and its safety make it a desirable first choice. It has been used as a first method in HIV screening the positive cases are then reexamined by blot immune assay for verification. The advantages of the technique make it...