25 Oesophageal Cancer

Oesophageal Cancer Brachytherapy

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THE GEC ESTROHANDBOOKOF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 10/06/2019

in order to assess the effectiveness of local palliative treatments [Homs et al., Amdal et al. Bergquist et al.]. There is no consensus regarding the optimal palliative local treatment. In general, the use of stents achieves an immediate effect on dysphagia [Homs et al.]. Endoluminal brachytherapy, in contrast, has a longer-lasting effect [Homs et al., Amdal et al., Bergquist et al.], and is superior in terms of health-related quality of life [Bergquist et al.].

the oesophageal lumen is filled the mucosa and submucosa are smoothed, pressed against the elastic muscle layers and thus the whole oesophageal wall is thinned, with the thickness usually less than 3 mm. Xia et al. found in a study on CT images an average oesophagus wall thickness between 1.87 and 2.70 mm when the oesophagus was dilated [Xia et al.] (fig. 27.1).

4. PATHOLOGY

3. ANATOMICAL TOPOGRAPHY

Tumours of the upper two thirds are mostly squamous cell carcinoma, while adenocarcinoma is the predominant type occurring in the lower third [Yang et al.]. In Western countries, the incidence of squamous cell carcinoma subtype is declining, while the incidence of OAC subtype is on the rise [Cook et al.]. Submucosal microscopic tumour spread is common and may extend longitudinally and radially in up to two thirds of patients [Landau et al.]. Depending on tumour volume, tumour extension in the oesophageal wall in the transverse plane may vary from a fewmm up to >20 - 30 mm. Lymph node involvement for several centimetres in the proximal and distal directions is also very common and is strongly linked to submucosal invasion [Raja et al.]. Raja et al. showed that with an increase of submucosal invasion

The oesophagus extends approximately from the level of the 6th cervical vertebra to the 11th thoracic vertebra and is an elastic tube about 25 cm long, which is - if empty - in the transverse cross section similar to a thumb, with a diameter of up to 2 cm in the latero- lateral and about 1-1.5 cm in the anteroposterior direction. The mucosa is folded in the longitudinal direction giving the transverse section a star-like appearance. The submucosa is loose allowing for folding of the mucosa and may reach a thickness of about 5 millimetres, if the lumen is not filled. The muscle layers are thin. The shape in the transverse section is very dependent on the state of filling: this may be with food or a tube which is introduced. When

Fig. 27.1: Cross sectional anatomy of the oesophagus with its different layers: mucosa, muscularis mucosae, submucosa, circular and longitudinal muscle (magnification factor 4). The thickness of these layers is highly dependent on the filling status.

Fig. 27.1A. Anatomy with an intraluminal applicator 15 mm in diameter: flattened layers of the wall, in particular the sub-mucosa: wall thickness varying from 1.87-2.7 mm (mean 2.1 mm; Xia et al. 2009)

Fig. 27.1B. Normal anatomy with a star like irregular mucosa and submucosa: wall thickness varying from 4.44-4.95 mm (mean 4.7 mm; Xia et al. 2009)