151751-Najiba-Chargi

20 CHAPTER 1 Therefore, in Chapter 9 we investigated the predictive impact of low skeletal muscle mass and arterial calcification on the occurrence of pharyngocutaneous fistula in patients with laryngeal cancer undergoing total larynx extirpation. Part III of this thesis presents the predictive and prognostic impact of skeletal muscle mass in head and neck cancer patients treated with systemic therapy. Because the effect of skeletal muscle mass on (dose limiting) toxicity and survival may be different for different anti-cancer drugs, we investigate, besides cisplatin, also other anti-cancer drugs. The impact of low skel - etal muscle mass may also differ for specific subgroups with favourable treatment outcome; therefore, we investigate its predictive and prognostic impact in patients with oropharyngeal cancer. Moreover, we also investigate the association of skeletal muscle mass and functional outcome after non-surgical treatment of head and neck cancer. In Chapter 10 , we investigated the predictive impact of low skeletal muscle mass on cisplatin dose-limiting toxicity in pa- tients with locally advanced head and neck cancer who were treated with chemoradiotherapy. Chapter 11 presents the same study as described in Chapter 10 in another hospital to validate the predictive impact of low skeletal muscle mass on cisplatin dose-limiting toxicity and to investigate the prognostic impact for survival in patients with head and neck cancer treated with chemoradiotherapy. Sometimes head and neck cancer patients are not fit enough to receive cisplatin-based chemoradiotherapy and these patients are offered cetuximab-based bioradiotherapy. Therefore, in Chapter 12 we present the predictive and prognostic impact of low skeletal muscle mass on cetuximab dose-limiting toxicity and survival in patients with head and neck cancer treated with bioradiotherapy. Besides the impact of skeletal muscle mass on cisplatin toxicity and cetuximab toxicity in patients with head and neck cancer, we investigated the impact on other anti-cancer drug toxicity in a variety types of cancers by a systematic review and meta-analysis presented in Chapter 13. To further investigate the hypothesis of the relationship between cisplatin pharmacokinetics and skeletal muscle mass in locally advanced head and neck cancer patients treated with chemoradiotherapy, we per- formed a prospective observational study, presented in Chapter 14. Because cislaptin itself is also thought to influence skeletal muscle mass changes, we investigated in Chapter 15 the patterns, predictors and prognostic impact of skeletal muscle mass loss after cisplatin-based chemoradiotherapy in patients with head and neck cancer. For the subgroup of oropharyngeal cancer patients, in Chapter 16 we investigated the prognostic impact of low skeletal muscle mass for decreased survival in patients with oropharyngeal squamous cell carcinoma. In Chap- ter 17 we present a prospective observational study describing the impact of low skeletal muscle mass on functional outcomes after radiation-based treatment in patients with locally advanced oropharyngeal carcinoma. Approximately a quarter of HNSCC patients is older than 70 years at diagnosis. This percent - age is expected to increase in the upcoming decades. Therefore, in Part IV of this thesis we present the predictive and prognostic impact of skeletal muscle mass in elderly head and neck cancer patients. Because both low skelatal muscle mass and frailty are prognostic and predictive factors and are both common in the elderly, we investigate their association and