Four hundred and fifty-three cases of squamous cell carcinoma of the larynx were treated during the period from 1969 to 1978 at the Department of Otolaryngology, Kobe University Hospital. Two hundred and flinty-cases were treated by irradiation therapy and one hundred and five cases developed local recurrence following initial irradiation. In 17 cases radical reirradiation was performed for local recurrence. Seven cases were successful and ten unsuccessful. Eight of the latter received total laryngectomy with good results.
In all of the unsuccessful reirradiation cases, the involvement of the anterior commissure was macroscopically evident before the initial irradiation and the reirradiation, and in the removed specimen observed microscopically following the failure of reirradiation. In the successful reirradiation cases on the other hand, the anterior commissure was not involved on clinical examination. Based on the above-mentioned fact, the choice of reirradiation for the relapsed laryngeal carcinoma should be confined to those in whom the involvement of the anterior commissure is completely deniable.
On histopathological study, the effect of irradiation is different in each specimen examined regardless of the similarity in type and amount of irradiation. A centripetal shrinkage of the tumor was not seen in any microscopically examined specimens, but islands of the tumor left in the primarily involved area was the marked finding which was obtained.