Myometrial And Ovarian Lesion 1 PDF
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Uploaded by PlentifulGrowth
Madonna University
Dr. C.C OGBU
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Summary
This presentation details myometrial and ovarian lesions, covering topics such as leiomyomas, morphology, and potential complications. It also discusses rare variants like intravenous leiomyomatosis and disseminated peritoneal leiomyomatosis. The document further details the potential for malignant transformation and survival rates for different types of lesions.
Full Transcript
Leiomyoma Uterine leiomyoma (commonly called fibroid) is perhaps the most common tumor in women. They are benign smooth muscle neoplasms. They may occur singly, but more often are multiple. Most leiomyomas have normal karyotypes, but approximately 40% have a simple chromosoma...
Leiomyoma Uterine leiomyoma (commonly called fibroid) is perhaps the most common tumor in women. They are benign smooth muscle neoplasms. They may occur singly, but more often are multiple. Most leiomyomas have normal karyotypes, but approximately 40% have a simple chromosomal abnormality. Morphology Leiomyomas are sharply circumscribed, discrete, round, firm, gray-white tumors. They vary in size from small, barely visible nodules to massive tumors that fill the pelvis. Except in rare instances, they are found within the myometrium of the corpus. Only infrequently do they involve the uterine ligaments, lower uterine segment, or cervix. They can occur within the myometrium (intramural), just beneath the endometrium (submucosal) or beneath the serosa (subserosal). The characteristic whorled pattern of smooth muscle bundles on cut section usually makes these lesions readily identifiable. Large tumors may develop areas of yellow-brown to red softening. Leiomyomas are composed of bundles of smooth muscle cells that resemble the uninvolved myometrium. Usually, the individual muscle cells are uniform in size and shape and have a characteristic oval nucleus and long, slender bipolar cytoplasmic processes. Mitotic figures are scarce. Morphologic variants include leiomyoma with bizarre nuclei, which has nuclear atypia and giant cells, and cellular leiomyomas. Both have a low mitotic index, helping to distinguish these benign tumors from leiomyosarcoma. An extremely rare variant, intravenous leiomyomatosis, is a uterine leiomyoma that extends into vessels and spreads hematogenously to other sites, most commonly the vena cava and the right atrium. Another variant, disseminated peritoneal leiomyomatosis, presents as multiple small peritoneal nodules. Both are considered benign despite their unusual behavior. Uterine leiomyomas, even when large or numerous, may be asymptomatic. Common signs and symptoms include abnormal bleeding, urinary frequency due to compression of the bladder, sudden pain from infarction of a large or pedunculated tumor, and impaired fertility. In pregnant women, leiomyomas may increase the frequency of spontaneous abortion, fetal malpresentation, uterine inertia (failure to contract with sufficient force), and postpartum hemorrhage. Malignant transformation to leiomyosarcoma is extremely rare. Leiomyosarcoma These uncommon malignant neoplasms are thought to arise from the myometrium or endometrial stromal precursor cells, rather than leiomyomas. In contrast to leiomyomas, leiomyosarcomas have complex, highly variable karyotypes that frequently include deletions. Like leiomyomas, a subset contains MED12 mutations, a genetic aberration that appears to be virtually unique to uterine smooth muscle tumors. Morphology Leiomyosarcomas grow within the uterus in two somewhat distinctive patterns: (⑴) bulky, fleshy masses that invade the uterine wall (⑵) or polypoid masses that project into the uterine lumen. They exhibit a wide range of cytologic atypia, from extremely well differentiated to highly anaplastic. The distinction from leiomyoma is based on nuclear atypia, mitotic index, and tumor necrosis. With few exceptions, the presence of 10 or more mitoses per 10 high-power (400×) fields indicates malignancy, particularly if accompanied by cytologic atypia and/ or necrosis. If the tumor contains nuclear atypia or large (epithelioid) cells, five mitoses per 10 high-power (400×) fields are sufficient to justify a diagnosis of malignancy. Rare exceptions include mitotically active leiomyomas in young or pregnant women, and caution should be exercised in interpreting such neoplasms as malignant. A proportion of smooth muscle neoplasms may be impossible to classify and are called smooth muscle tumors of “uncertain malignant potential.” Leiomyosarcoma occurs both before and after menopause,with a peak incidence at 40 to 60 years of age. These tumors often recur following surgery, and more than one-half eventually metastasize hematogenously to distant organs, such as lungs, bone, and brain. Dissemination throughout the abdominal cavity is also encountered. The overall 5-year survival rate is about 40%, but the anaplastic lesions have a 5-year survival rate of only 10% to 15%. The most common lesions encountered in the ovary are functional or benign cysts and tumors. Neoplastic disorders can be grouped according to their origin from each of the three main ovarian cell types: (1) müllerian epithelium, (2)germ cells, and (3) sex cord–stromal cells. Primary inflammations of the ovary (oophoritis) are uncommon, and on rare occasions may have an autoimmune basis (autoimmune oophoritis); the autoimmune reactions affect the ovarian follicles and may lead to infertility. Follicle and Luteal Cysts Cystic follicles are very common in the ovary. They originate from unruptured graafian follicles or in follicles that have ruptured and immediately sealed. Morphology These cysts are usually multiple. They range in size up to 2 cm in diameter, are filled with a clear serous fluid, and are lined by a gray, glistening membrane. On occasion, larger cysts exceeding 2 cm (follicle cysts) may be diagnosed by palpation or ultrasonography; these may cause pelvic pain. Granulosa lining cells are present if the intraluminal pressure has not been so great as to cause their atrophy. The outer theca cells may be conspicuous due to increased amounts of pale cytoplasm (a change referred to as luteinization). As discussed later, when luteinization is pronounced (hyperthecosis), it may be associated with increased estrogen production and endometrial abnormalities. Luteal cysts (corpora lutea) are present in the normal ovaries of women of reproductive age. They are lined by a rim of bright yellow tissue containing luteinized granulosa cells and are prone to rupture, which may produce a peritoneal reaction. Sometimes the combination of old hemorrhage and fibrosis may make their distinction from endometriotic cysts difficult. Polycystic ovarian syndrome (PCOS) is a complex endocrine disorder characterized by hyperandrogenism, menstrual abnormalities, polycystic ovaries, chronic anovulation, and decreased fertility. Formerly called Stein Leventhal syndrome, it affects 6% to 10% of reproductive age women worldwide. It is also associated with obesity, type 2 diabetes, and premature atherosclerosis, all of which may be indicative of an underlying metabolic disorder. The etiology of PCOS remains incompletely understood. It is marked by a dysregulation of enzymes involved in androgen biosynthesis and excessive androgen production, which is considered to be a central feature of this disorder. In addition, women with PCOS show insulin resistance and altered adipose tissue metabolism, which contribute to the development of both diabetes and obesity. The central morphologic abnormality of PCOS is numerous cystic follicles or follicle cysts that enlarge the ovaries. However, polycystic ovaries are detected in 20% to 30% of all women, so this finding is not specific. In addition, due to an increase in free serum estrone levels, women with PCOS are at risk for endometrial hyperplasia and carcinoma. THANK YOU FOR LISTENING
