Author Information
Parulekar SV
(Professor and Head. Department of Obstetrics and Gynecology,
Seth G.S.
Medical College
and K.E.M Hospital ,
Mumbai , India
Abstract
Leiomyomas are benign tumors arising from the myometrium
affecting up to 30% of all women in the reproductive age group. Broad ligament
leiomyomas account for less than 1% all leiomyomas. True broad ligament
leiomyomas are conventionally believed to develop from mesenchymal remnants
founding the broad ligament, or smooth muscle in the media of blood vessels. A new
theory of development of a true broad ligament leiomyoma is presented.
Introduction
Leiomyomas are benign tumors arising from the myometrium
affecting up to 30% of all women in the reproductive age group. Broad ligament
leiomyomas account for less than 1% all leiomyomas. A false broad ligament
leiomyoma develops laterally from the lateral surface of the uterus. A true broad ligament leiomyoma is conventionally
believed to develop from mesenchymal remnants founding the broad ligament, or
smooth muscle in the media of blood vessels in the broad ligament. A case that
supports conversion of a false broad ligament leiomyoma into a true broad
ligament leiomyoma is presented. It is proposed that elongation and thinning of
the pedicle of a false broad ligament leiomyoma finally results into its
necrosis so that the leiomyoma loses its attachment to the uterus and gets
classified as a true broad ligament leiomyoma.
Theory
It is theorized that sometimes a true leiomyoma develops by
severance of the pedicle of a false broad ligament leiomyoma.
Discussion
Leiomyomas are benign tumors arising from the myometrium.
They affect up to 30% of all women in the reproductive age group. Extra-uterine
leiomyomas are rare. Broad ligament leiomyomas are the most common tumors among
the extra-uterine leiomyomas, though their overall incidence is less than 1%.[1]
These are the most common forms of
mesenchymal tumors found in the broad ligaments.[2] But mesenchymal
tumors are rare in the broad ligaments, the most common type being epithelial
tumors.[3] Broad ligament leiomyomas are of two types- false and
true. The main difference between the two is that a false one has a pedicle
connecting it to the uterus, while a true type has no connection with the
uterus. Distinction between the two types is not merely of academic interest. A
false broad ligament leiomyoma usually lies above the uterine vessels, and when
it enlarges, the ureter lies below and lateral to it. A true broad ligament
leiomyoma develops anywhere in the broad ligament, and hence the ureter can lie
above, below, medial, or lateral to the leiomyoma. Localization of the ureter
with respect to the broad ligament leiomyoma is essential prior to dissection,
cutting and ligation of any tissue around the leiomyoma, so that ureteric
injury is prevented. Another reason for making the distinction preoperatively
is that a false broad ligament leiomyoma has a pseudocapsule, so that when the
pseudocapsule is divided and dissection is done within the pseudocapsule, the
leiomyoma can be enucleated without any fear of injuring the ureter. A true
broad ligament leiomyoma does not have a pseudocapsule, and its enucleation is
much more difficult than that of a false broad ligament leiomyoma, and also
associated with a greater risk of injury to the ureter.[4]
False broad ligament leiomyomas arise from the lateral walls
of the uterus or supravaginal cervix, and grow laterally into the broad
ligament.[5] True broad ligament leiomyomas are said to develop from
the mesenchymal remnants founding the broad ligament, or smooth muscle in the
media of blood vessels.[6]
Figure 1. False broad ligament leiomyoma on the left side of
the uterus, exposed by opening the left broad ligament. The long, narrow
pedicle is seen connection the leiomyoma to the lower, lateral surface of the
uterus.
Figure 2. Hysterectomy specimen of the same case. The
pedicle is 5 cm long and a few millimeters in diameter.
In the case presented here, the false broad ligament
leiomyoma had a 5 cm long pedicle which measured a few millimeters in diameter.
Considering the size of the leiomyoma, it appeared that the blood supply to the
leiomyoma through the vessels in that thin pedicle would reduce to almost nil
after the pedicle elongated and thinned further. Finally when the leiomyoma
acquired its blood supply through the blood vessels in the connective tissue of
the broad ligament, the long pedicle would necrose and the leiomyoma would have
no connection with the uterus. This an original false broad ligament leiomyoma
would get converted into a true broad ligament leiomyoma.
This is the first demonstration of elongation and thinning
of the pedicle of a false broad ligament leiomyoma almost to the point of its
necrosis, so that the leiomyoma would lose its connection with the uterus. Thus
it is likely that all true broad ligament leiomyomas do not necessarily develop
from mesenchymal remnants or smooth muscle in the media of blood vessels in the
broad ligament, and some of them develop due to necrosis of their pedicles
connecting them to the lateral surface of the uterus.
Acknowledgements
I thank Dr Shruti Kulkarni for taking the photographs used as illustrations in this article.
References
1.
Kumar P, Malhotra N. Tumors of the
Corpus Uteri. In Jeffcoate's Principles of Gynecology. 7th Ed. New Delhi
2.
Breen JL, Neubecker RD. Tumors of
round ligament: A review of literature and a report of 25 cases. Obstet Gynecol
1962;19:771-80.
3.
Thor AD, Young RH, Clement PB.
Pathology of fallopian tube, broad ligament, peritoneum and pelvic soft
tissues. Hum Pathol 1991;22:856-67.
4.
Parulekar SV. Practical Gynecology and Obstetrics. 5th
ed. Mumbai: Vora Medical Publications; 2011. p 348
5.
Parker WH.
Uterine myomas: an
overview of development, clinical features, and
management. Obstet Gynecol 2005;105:216-7.
6.
Heinzman AB. Pelvic
Mass. New
York
Citation
Parulekar
SV. Genesis of True Broad Ligament Leiomyoma. JPGO 2014 Volume 1 Number 8. Available from: http://www.jpgo.org/2014/08/genesis-of-true-broad-ligament-leiomyoma.html