Early Stage Oral Squamous Cell Carcinoma: Treatment and Diagnostic Dilemmas

Abstract

In the treatment of early stage oral squamous cell carcinoma (OSCC) there has not been a substantial improvement in survival over the last three decades. To optimize future treatment results, it is relevant to critically review current diagnostic techniques and treatment strategies. This thesis addresses some key topics that play a central role in frequent discussions, such as; the diagnostic value of the biopsy, the prognostic value of unfavorable histological growth parameters, the reproducibility of these parameters, the consequences of close resection margins and the best approach for the clinically negative neck. The goal of this thesis is to find evidence, for frequently used treatment modalities and uncover shortcomings to refine current treatment options. Main conclusions: -Prognostic growth parameters found in the incisional biopsies do not represent the resection specimen and have no value in treatment planning. -Determination of differentiation grade on biopsy- and resection specimen is of no prognostic value concerning regional metastasis and survival. -With at most a moderate inter observer agreement in the determination of pathological growth parameters on digital slides. The reproducibility is not reliable enough to guide adjuvant treatment planning. -In early stage OSCC a clear margin of ≥3mm is as safe as ≥5mm. -Watchful waiting of the neck in early stage OSCC is unfavorable for patients with occult metastasis as they show more extracapsular spread and a worse disease specific survival compared to patients treated with a selective neck dissection. -Our nomogram “Oral Oncoprognostic” is a useful tool to predict overall survival in post-operative OSCC patients. The nomogram can support patient counseling and individualized treatment planning.