Single Disseminated Tumor Cell Detection in Peripheral Blood Sample of Patients with Oral Squamous Cell Carcinoma Using MAGE-A4: Table 1

Circulating Tumor Cells in Oral Cancer

Till now, oral squamous cell carcinoma (OSCC) is graded as well-differentiated, moderately-differentiated, poorly-differentiated, and undifferentiated. However, this grading does not have a prediction of the prognosis of the patient. Also, prognosis impacts lymph node metastases, surgical margins, and vascular invasions (neural invasion, muscular invasion, salivary gland invasion). The prognosis of lymph node metastases is significant, which affects the survival of the patients which is 50%. So, a dependable blood marker is needed for prognosis in OSCC patients with loco-regional and distant recurrence. Some factors can be assisted only after surgery and invasive techniques to check the prognosis of the disease. Despite the ease of examining the oral cavity, there is no practical approach for non-invasive screening and detecting cancer. As it is abrupt to use such invasive procedures from time to time, there is a need for nonsurgical and reliable techniques to assess the progression of tumors. Also, frozen sections are helpful during the intraoperative procedure to evaluate the lymph node metastases. An increase in the number of tumor cells through blood is a significant event in disease metastases toward the peripheral blood. Oral health impact assessment instruments could aid in determining the quality of life, and their usage in the initial stages of oral carcinoma could help physicians choose the best treatment option for enhancing the quality of life.

Circulating Tumour Cells (CTC), Head and Neck Cancer and Radiotherapy; Future Perspectives

Head and neck cancer is the seventh most common cancer in Australia and globally. Despite the current improved treatment modalities, there is still up to 50⁻60% local regional recurrence and or distant metastasis. High-resolution medical imaging technologies such as PET/CT and MRI do not currently detect the early spread of tumour cells, thus limiting the potential for effective minimal residual detection and early diagnosis. Circulating tumour cells (CTCs) are a rare subset of cells that escape from the primary tumour and enter into the bloodstream to form metastatic deposits or even re-establish themselves in the primary site of the cancer. These cells are more aggressive and accumulate gene alterations by somatic mutations that are the same or even greater than the primary tumour because of additional features acquired in the circulation. The potential application of CTC in clinical use is to acquire a liquid biopsy, by taking a reliable minimally invasive venous blood sample, for cell genotyping during radiotherapy treatment to monitor the decline in CTC detectability, and mutational changes in response to radiation resistance and radiation sensitivity. Currently, very little has been published on radiation therapy, CTC, and circulating cancer stem cells (CCSCs). The prognostic value of CTC in cancer management and personalised medicine for head and neck cancer radiotherapy patients requires a deeper understanding at the cellular level, along with other advanced technologies. With this goal, this review summarises the current research of head and neck cancer CTC, CCSC and the molecular targets for personalised radiotherapy response.