[Extensive fibromatosis of the neck muscles]

Extensive fibromatosis, also called desmoid tumor, is a histologically benign tumor, which is nonetheless serious due to its recurrent character and to its potential for infiltration of neighboring tissues. Extensive surgery is the only effective means of treatment, radiation therapy being used only as a complement. The authors describe an elective location of the lesion in the sheaths of the scalenus muscles. This development is usually observed in young women, as is the case in the observation reported here.