[Pseudosarcomatous leiomyomas of the uterus. Fusiform cell myomas, plexiform myomas and myomas with nuclear anomalies].

The authors report 14 cases of atypical myomata wich might have been mistaken for sarcomata were it not for the fact that they were devoid of mitotic features. Four of the myomata were immature types with small fusiform cells and without connective tissue fibres. Two of the myomata had a plexiform structure several cm. in diameter and appaered to correspond to tissue that was undergoing endothelial and periocytal regeneration round an old focus of necrosis. These features could only be made out precisely under the microscope. The other eight myomata were mature in form and associated with abnormal nuclei (large, hyperchromatic irregular multi-nuclear giant cell clumps) surrounding the periphery of centres of hypoxia, more commonly after pregnancy (3 cases) or treatment with progesterone (2 cases).