Vascular system of intramural leiomyomata revealed by corrosion casting and scanning electron microscopy.
BACKGROUND
The vascular system of leiomyomata, the most common benign tumours in women, is an important factor controlling development and growth of the tumour. It has not been, however, investigated morphologically using the best currently available technique, corrosion casting combined with scanning electron microscopy.


METHODS
Myomatous uteri collected upon autopsy were perfused via afferent vessels with fixative followed by Mercox resin and corroded after polymerization of the resin. The obtained vascular casts visualizing all vessels including capillaries were examined using scanning electron microscopy.


RESULTS
The smallest (1-3 mm) fibroids were avascular, in larger ones (<1 cm) a few small vessels invaded the lesion from the periphery. The largest tumours (>1 cm) contained irregular networks of blood vessels with density similar to or lower than that of normal myometrium. Such tumours were surrounded by an extremely dense vascular layer ('vascular capsule') which was the source of larger vessels supplying and draining the tumour.


CONCLUSIONS
During development of leiomyoma, the pre-existing blood vessels undergo regression and new vessels invade the tumour from the periphery, where intense angiogenesis, probably promoted by growth factors secreted by the tumour, leads to the formation of a 'vascular capsule' responsible for supply of blood to the growing tumour.
Departments of Anatomy, Histology and Laboratory of Scanning Electron Microscopy, Jagiellonian University Medical College, Kopernika 12, 31-034 Kraków, Poland. mburbani@cyf-kr.edu.pl
Jerzy A
JA
Walocha
Jan A
JA
Litwin
Adam J
AJ
Miodoński
D000328:Adult; D000368:Aged; D001808:Blood Vessels / Q000648:ultrastructure; D016319:Corrosion Casting; D005260:Female; D006801:Humans; D007889:Leiomyoma / Q000098:blood supply*; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D014594:Uterine Neoplasms / Q000098:blood supply*