This avoids under-representing an ulcerated tumour or over-representing an exophytic tumour, and has been included in staging for OCSCC in the current 8th edition American Joint Committee on Cancer (AJCC) staging manual. DOI is measured from the level of the basement membrane to the deepest point of invasion, and in the case of an ulcerated OCSCC, this level is estimated by creating an imaginary line from the adjacent basement membrane. Tumour thickness measures the thickness of the tumour from the deepest point of invasion to the top of the granular cell layer, or if ulcerated, the ulcer base serves as the reference point. Various parameters have been investigated to further stratify the risk of subclinical nodal metastases, including tumour thickness and depth of invasion (DOI). This chapter will present the histopathological factors that have been used to risk stratify patients for an END, as well as the multifaceted technique and role of sentinel lymph node biopsy (SLNB) as a staging procedure for patients with OCSCC. Traditionally the only way to identify this was to perform an elective neck dissection (END), however this is unnecessary in the majority (60–80%) of patients who do not harbour occult nodal metastases, and has an associated morbidity. Current imaging techniques including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET) and ultrasound (US) cannot accurately identify micrometastases preoperatively. The presence of nodal metastases has been shown to be the strongest independent prognostic factor for predicting a poor outcome. Early stage oral cavity squamous cell carcinoma (T1N0 or T2N0) has a significant risk of between 20 and 44% of harbouring subclinical nodal metastases.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |