Compare the role of positron emission tomography scan to conventional imaging in the evaluation of advanced head and neck cancers

Abstract

INTRODUCTIONHead and neck cancer is the most common cancer in India. The most common site involved is oral cavity. The other common sites are larynx, hypopharynx and nasopharynx. Radiology in form of CT/MRI is the mainstay of assessing and staging advanced head and neck malignancy. Magnetic resonance imaging is the preferred tool for investigating the primary tumour in all head and neck sites, particularly for assessing cartilage, bone, perineural, and perivascular invasion. Imaging is crucial to know the site, extent and infiltration to the adjacent structures of a histologically proven primary tumour and to detect the presence of enlarged lymph nodes. After imaging, the staging of the tumour or node is upgraded in at least 30% of cases. 1The incidence of distant metastasis in advanced head and neck malignances is influenced by various factors like location and size of primary tumour (T), lymph node stage and local control of disease above the clavicle. Lung metastases are most common in squamous cell carcinoma accounting for around 66% other being bone. Hence it is imperative to diagnose distant metastasis at initial presentation.2 Whole body PET-CT helps in the detection of distant metastasis especially in high risk and advanced head and neck squamous cell carcinoma.The aim of the study to the compare the role of PETCT scans to MRI in the initial evaluation in advanced cancers of head and neck. ABSTRACTBackground: Advanced stages of head and neck cancers need careful evaluation by imaging to rule out multiple nodal and distant metastasis which might influence management and prognosis. The aim of the study was to compare the role of PETCT scan to MRI in the initial evaluation in advanced cancers of head and neck. Methods: The study included 46 patients having advanced stages of head and neck squamous cancers. The patients underwent clinical examination, endoscopy, an initial CT/MRI of the disease site and conventional metastatic workup with an X-ray Chest and USG abdomen. The patients then underwent PET/CT. Tumor restaging was done after the PETCT and the results of CT/ MRI to PETCT were compared. Results: There was upstaging of disease in patients with identification of multiple/ bilateral nodes and distant metastasis following PETCT. Conclusions: PETCT scan has an impact on the initial upstaging staging of disease compared to conventional imaging.