MIOMA SUBMUKOSA (Submucosal Myoma)

Authors : Aulia Rahman, S.Ked, Endang Sri Wahyuni, S.Ked, Nova Faradilla, S.Ked. Fakultas Kedokteran Universitas Riau. 2009

—-

INTRODUCTION

—- Leiomyomas (also called myomas or fibroids) are benign tumors of the uterus and are composed mainly of smooth muscle with some fibrous connective tissue elements. Myomas are the most common pelvic tumors and one third of the hysterectomies performed annually are for fibroids. Approximately 20% to 25% of women older than 35 years have a uterine myoma. Myomas are usually asymptomatic, more common in black women than in white women, rare before puberty, and usually shrink after menopause. They are estrogen-dependent and may grow during estrogen replacement therapy (peri- and postmenopausal) or during pregnancy. They are single or, more commonly, multiple tumors in the uterine corpus (i.e., intramural, subserosal, or submucosal). They can be pedunculated and, on occasion, involve the cervix, round ligament, or broad ligament. ¹

–

LITERATURE

DEFINITION

Myomas are benign tumors derived from the smooth muscle cells of the myometrium. They are the most common neoplasm of the uterus. but most are asymptomatic. However, myomas can cause excessive uterine bleeding, pelvic pressure and pain, as well as infertility.²

EPIDEMIOLOGY

Estimates are that more than 45% of women have myomas by the fifth decade of life. They are the primary indication for 200,000 to 300,000 hysterectomies in the United States each year. Although myomas have the potential to grow to impressive sizes, their malignant potential is minimal. Sarcomatous changes occur in less than 1 per 1000 uteri with fibroids. ²

RISK FACTOR

Risk factors for developing myomas include increasing age during the reproductive years, ethnicity (African-American women have at least a 2- to 3-fold increased risk compared to Caucasian women), nulliparity, and family history. The data are suggestive that higher body mass index is associated with a greater risk of myomata. Oral contraceptive pills and depot medroxyprogesterone acetate (DMPA) injections may be associated with reduced risk^{. 2}

PATHOGENESIS

Factors that initiate myomas are not known, but ovarian sex steroids are important

for their growth. myomas rarely develop before menarche and seldom develop or enlarge after menopause, unless stimulated by exogenous hormones. Myomas can also enlarge dramatically ding pregnancy. Myomas have increased levels of estrogen and progesterone receptors compared to other smooth muscle cells. Estrogen stimulates the proliferation of smooth muscle cell, whereas provgesterone increases the production of proteins that interfere with programmed cell death (or apoptosis). Myomas also have higher levels of growth factors that stimulate the production of fibronectin and collagen, major components of the extracellular matrix that characterizes these lesions. ²