Smooth-muscle tumours of the upper respiratory tract.

SUMMARY Tumours arising from the smooth muscle of the upper respiratory tract are extremely rare. Three cases occur­ ring in South African Bantu are reported; one, a leiomyo­ sarcoma of the larynx, the second a vascular leiomyoma of the nasal cavity, and the third a leiomyoma of the larynx. The literature is reviewed. S. Afr. Med. J., 47,1189 (1973). Although leiomyomas are uncommon outside the uteru, and the gastro-intestinal tract, they may occur in the skin and subcutaneous tissues, the lung, kidney, broad ligament, mesentery, omentum, retroperitoneum, mediastinum, major arteries and veins, and orbit. Malignant smooth-muscle tumours ar.': also uncommon in the soft somatic tissues. Stout and Hill' reported 35 such tumours in the skin and subcutaneous tissues. Recorded at the Armed Forces Institute of Pathology are 462 leiomyosarcomas,' of which 125 (27%) arose in soft tissues; the distribution was: retroperitoneal 76, deep tissues of the extremities 23, subcutaneous 10, omental and mesenteric 8, in the venous system 3, in the abdominal wall 2, orbital 2, mediastinal I. The highest incidence of leiomyosarcomas occurs be­ tween the fourth and sixth decades,' but Yamopoulos and Stou·.' have described 9 cases in children under 16 years of age. Both benign and malignant tumours of smooth muscle are rare in the upper respiratory tract. The Registry of the Armed Forces Institute of Pathology contains records of only 6 cases of leiomyomas of the upper respiratory tract. These tumours were found in the nasal cavity, the larynx, the skin of the nose, the hypopharynx and the trachea.' Leiomyosarcomas of the larynx are extremely rare. Eggston and Wolff' mention 2 cases, in I of which a laryngectomy was performed. Single cases have been reported by Kawabe: and by Amendolea,' and we are aware of a patient treated by laryngectomy by Kay' who has survived for over 3 years. An interesting case was recorded by Jackson and Jack:;on' -the tumour originated in the oesophagus and involved the larynx. The authors believed this to have been a leiomyoma that underwent sarcomatous change. According to Kawabe et al.,'· in 1969 there were 7 cases of leiomyo­ sarcomas of the nose, paranasal sinuses and nasopharynx in the literature. One of these, reported by PimpineUa and Marquit," commenced as a 'vascular bleeding lesion in the nasal cavity' which recurred 14 years after excision.