Leiomyoma (uterus)
Uterine leiomyoma is a hormone-dependent benign connective tissue tumor of the smooth muscle cells of the myometrium. It is the most frequent uterine tumor.
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Figure 1
Gross examination : The tumor can be single or multiple (leiomyomatosis) (Figure 1), variable in size. It can reach large sizes (over 10 cm.) causing pain, meno-metrorrhagia / abnormal bleeding, urinary dysfunction and infertility.
In this case, the uterine body / corpus is enlarged and deformed. The cut surface shows multiple nodules, well-circumscribed, firm, white-greyish with a whorled appearance formed by the intersecting bundles of brown muscle fibers and white fibrous tissue. Leiomyomas can also present bleeding areas, cystic degeneration and calcifications. The uterine cavity is compressed.
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Figure 2
The tumors can occur intamural, submucous and / or subserous (Figure 2).
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Figure 3
Most leiomyomas are intramural, occupying the middle portion of the myometrium. Another topographic classification divides leiomyomas into : cervical (Figure 3), isthmic and of the uterine body (which is the most frequent - 96 %).
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Microscopy : Tumor cells resemble normal cells (uniform, elongated, spindle-shaped, with a cigar-shaped nucleus) and form bundles with different directions (whirled). The tumor may present areas of fibrosis, calcification and / or hemorrhage. The tumor is well circumscribed, but not encapsulated. (Hematoxylin-eosin, ob. x10)
Additional information :