Pharyngocutaneous fistula and total laryngectomy: possible predisposing factors, with emphasis on pharyngeal myotomy.

Ninety-two total laryngectomy cases were investigated with reference to post-laryngectomy fistula formation. Fistula was observed in eight cases (8.69 per cent). There were no statistically significant differences between the fistula group and the non-fistula group with regard to pre-operative tracheotomy, tumour differentiation, positive surgical margins, concurrent neck dissection, previous radiotherapy, T stage of the tumour, presence of extended hypopharyngeal mucosal excision, and placement of nasogastric tube. The only statistically significant positive association was found with primary pharyngeal myotomy. Myotomy was performed in six of the fistula patients and in two cases a technical error was observed. In these cases myotomy was performed adjacent to the edge of hypopharyngeal mucosa resulting in a weakened area of pharyngeal closure, possibly contributing to the fistula. This should be kept in mind and avoided at all costs during the performance of myotomy. Since it was not possible to find out any specific causal relationship with myotomy in four other cases, further studies are needed to establish the association of myotomy with pharyngocutaneous fistula.