CANCER OF THE LARYNX
half and membrane the anterior half of the glottis. The length of the
adult male vocal cord is about 2 cm. This should mean that if a cancer is
confined to the vocal cord, it is less than 2 cm at its widest point and thus
should be eminently curable.
Tumours of this region present as two distinct types: (a) A small tumour
limited to the vocal cord (Plate K///, 1). (6) A large tumour involving the
glottis, supraglottis and subglottis—the so-called transglottic tumour. This
carries a high incidence (75 per cent) of lymph node rnetastases because it
involves both the rich lymphatic fields of the supraglottis and subglottis.
These tumours also spread to the strap muscles (5 per cent) and the thyroid
gland (10 per cent).
SYMPTOMS. Both tumours present with hoarseness. Why one should be seen
at a very much later stage than the other is unknown, but, in theory, if every
Fig. 86. Hemilaryngectomy. Showing the outline
of the perichondrial flap pedicled posteriorly.
Fig. 87. Hemilaryngectomy. I, Thyrohyoid muscle;
2, Sternohyoid muscle; 3, Sternothyroid muscle.
patient with hoarseness had the larynx examined within the first month then
all tumours should be seen at an early stage. This is not the whole story,
however, because the length of history of the transglottic variety is about the
same as the glottic group. Occasionally the transglottic group will present
with a gland in the neck in addition to hoarseness.
INVESTIGATION. As mentioned previously, if a glottic tumour is confined to
the vocal cord it is less than 2 cm in length and thus should be readily curable
with radiotherapy. While this gives good results it is by no means 100 per cent
successful. One of the reasons for the failures is that radiotherapy does not
sterilize cartilage well. Therefore in assessing the tumour it is essential to
gauge whether cartilage is involved or not. The cartilages that could be
affected are the arytenoid, by way of the vocal process, and the thyroid
cartilage at the anterior commissure. At laryngoscopy it is also essential to
assess the degree of mobility of the vocal cord, and to search for any extension
into the subglottis or supraglottis. It is unlikely that there will be any neck
glands palpable in the glottic tumours but a high chance exists of such