13 Head and Neck - Oropharynx

Head and Neck - Oropharynx

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THE GEC ESTROHANDBOOKOF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 15/02/2021

they observed only 11% ≥ grade 2 xerostomia and dysphagia ≥ grade2 was also as low as 8% [16]. Levendag et al studied 81 patients with oropharyngeal cancer who were treatedwith 3DCRT or IMRT [18]. Of these 41 patients received BT boost. They observed that patients who were treated with BT had much less physical dose to superior and middle constrictor muscle. This resulted in a statistically significant reduction in the dysphagia rates in the patients receiving BT compared to EBRT alone (Figure 31, 32). Thus BT appears to be a very useful treatment modality for reduction of xerostomia and dysphagia. These late sequelae are extremely important in long term survivors of oropharyngeal cancer and have a significant impact on quality of life.

enumerate the non-invasive nature of the technique along with the excellent control rates and xerostomia reduction as advantages of IMRT [64]. The proponents of BT describe it as one of the oldest techniques with excellent control rates [15]. However if we look at xerostomia reduction with IMRT around 35-50% of patients still have xerostomia after the treatment [25,26]. Hence there is a need to further reduce the late sequalae of treatment. BT is an excellent treatment modality which can further reduce xerostomia and dysphagia in patients with oropharyngeal cancers. Hence rather than considering IMRT vs BT there is a need to combine the two modalities together to achieve optimal outcomes. Currently however there is only one study which has shown benefits from the combined treatment [5]. To prove this point a randomized trial is being undertaken to compare IMRT alone vs IMRT with BT for reduction of xerostomia. This will hopefully validate the importance of adding BT to IMRT [65].

IMRT vs Brachytherapy Since the advent of IMRT, there has always been a debate about the role of BT in the era of IMRT. The proponents of IMRT

Figure 31: Probability of dysphagia was lower in patients treated with brachytherapy for oropharyngeal cancer (Levendag et al IJROBP 2008)

Figure 32: Patients treated with brachytherapy for soft palate and tonsil had much lower superior constrictor doses as compared to EBRT (Levendag et al RO 2008)

14. KEYMESSAGES

• Brachytherapy is a well-established treatment for a selected group of patients with oropharyngeal cancer • The use of BT is currently limited due to the required skills for a procedure which can be technically challenging • While there has been debate about the use of BT in the era of IMRT, a combined IMRT and BT approach has shown excellent outcomes.

• Currently the use of HDR and PDR is more common for oropharyngeal BT. • The outcomes with BT with or without EBRT are excellent in terms of local control. • Toxicity with HDR and PDR is lower than that of older LDR series.