| Abstract: |
There is no existing evidence that any screening test, including CA-125, ultrasound, or pelvic examination, reduces mortality from ovarian cancer. Furthermore, existing evidence that screening can detect early-stage ovarian cancer is insufficient to indicate that this earlier diagnosis will reduce mortality.Because there is a low incidence of ovarian cancer in the general population (age-adjusted incidence of 17 per l00,000 women), screening for ovarian cancer is likely to have a relatively low yield. The great majority of women with a positive screening test will not have ovarian cancer (i.e., they will have a false-positive result). In women at average risk, the positive predictive value of an abnormal screening test is, at best, approximately 2% (i.e., 98% of women with positive test results will not have ovarian cancer).The positive predictive value of an initially positive screening test would be more favorable for women at higher risk. For example, the lifetime probability of ovarian cancer increases from about 1.6% in a 35-year-old woman without a family history of ovarian cancer to about 5% if she has 1 relative and 7% if she has 2 relatives with ovarian cancer. If ongoing clinical trials show that screening has a beneficial effect on mortality rates, then women at higher risk are likely to experience the greatest benefit.Ovarian malignancies represent the greatest clinical challenge amongst all the gynecologic cancers. It has the highest fatality-to-case ratio of all the gynecologic malignancies.They are the cause of more deaths than any other female genital tract cancer. According to the latest statistics, about 26.500 new cases are diagnosed each year in the United States, and about 14.500 deaths occur annually as a result of this disease. It accounts for 5% of all cancers among women.Early ovarian carcinoma is a silent, asymptomatic disease, and approximately 75% of ovarian carcinomas have spread at the time of initial diagnosis.The cost of diagnosing a single curable ovarian cancer is between $500.000 and S1 million. Furthermore, yearly screening of most women aged > 45 in the United States has been estimated to cost $14 billion per year.The causes of ovarian cancer are poorly understood, but several factors have been associated with increasing or decreasing the risk of the disease.Age, nulliparity, infertility, history of endometrial or breast cancer, and family history of ovarian cancer have been consistently found to increase the risk for invasive epithelial ovarian cancer. Parity, oral contraceptive use, history of breast-feeding, tubal ligation, and hysterectomy have been associated with a reduction in risk.The etiology of ovarian cancer is multifactorial. Three hypotheses have been proposed to explain the etiology of ovarian cancer: the incessant ovulation, the gonadotropin, and the pelvic contamination hypotheses.Because most cases of ovarian cancer are advanced at the time of diagnosis and current treatment rarely is curative, significant effort has been expended to identify a cost-effective screening strategy that would allow earlier diagnosis and, therefore, higher cure rates. Currently, there is no proven method of screening for ovarian cancer. Suggested methods include pelvic examination, abdominal and transvaginal ultrasound, color Doppler, and analysis of CA125 levels in serum.Unfortunately, pelvic examination alone has not been found to be effective in reducing the mortality rate from ovarian cancer. Measurement of CA125 in serum appear to have a high false negative rate for early-stage disease. Additionally, this method appears to have a high false positive rate in premenopausal women, a group in whom most ovarian enlargements are benign. Abdominal and transvaginal ultrasound also have high false positive rates, particularly in premenopausal women. High frequency transvaginal ultrasonography can be said to improve characterization of the size and morphologic characteristics of the ovaries with better sensitivity than that offered by transabdominal ultrasonography. Although color Doppler ultrasound has not been used for initial screening programs, recent research has suggested that early ovarian malignancy may have abnormal color Doppler findings before morphologic abnormalities are detectable with standard transvaginal ultrasound. Therefore, if high-risk cases where to be screened, it would be appropriate to consider color Doppler transvaginal ultrasound.Until a prospective study has established the effectiveness of screening in a large population, routine screening by abdominal, vaginal ultrasound and color Doppler or measurement of CA125 levels in serum cannot be recommended for women with no known risk factors. For women with a documented, familial ovarian cancer syndrome who with to maintain their reproductive capacity, some authorities have suggested the use of transvaginal ultrasonography, analysis of levels of CA125 in serum, or both, in combination with frequent pelvic examination. The efficacy of this approach has not been established.Women who have demonstrated familial ovarian or hereditary breast-ovarian cancer syndromes and who do not with to maintain their reproductive capacity may be offered prophylactic bilateral salpingo-oophorectomy. Genetic testing would lead to identification of women at highest risk while avoiding surgery in those who do not have the gene mutation. The ethical implications of genetic testing must be fully understood by the patient and her physician. These women should be informed that removal of the tubes and ovaries does not provide 100% protection, primary peritoneal carcinoma has been reported after bilateral salpingo-oophorectomy.There are no early symptoms of cancer of the ovary. Most presenting symptoms are those associated with increasing tumor mass, spread of tumor along the serosal surfaces of the bowel, and ascites. Abdominal discomfort, upper abdominal fullness, and early satiety are associated with cancer of the ovary.The most frequently noted physical finding of ovarian cancer is a pelvic mass. Although the character of an adnexal mass (either cystic or solid) is not necessarily diagnostic, an adnexal mass that is bilateral, irregular, solid, or fixed suggests malignancy. Other findings suggestive of malignancy are ascites or a nodular cul-de-sac. The risk of ovarian cancer is significantly higher in premenarcheal and postmenopausal women with an adnexal mass than in women of reproductive age.The initial diagnostic workup should be aimed at evaluating whether an adnexal mass requires surgical intervention. Further, preoperative recognition of masses likely to represent ovarian cancer facilitates patient preparation, surgical staining, and cytoreduction. Finally, the workup should exclude other causes of an adnexal mass.Initial evaluation with a thorough history, physical examination, and vaginal probe ultrasonography will distinguish most benign masses from malignant masses.Several scoring systems have been applied for the ultrasound differentiation between benign and malignant ovarian tumors. The characteristics suggesting a higher probability of ovarian cancer include evidence of bilaterality, solid and cystic compounenents, excrescences, thick septations and the presence of free peritoneal fluid. Screening mammography, if it has not been done within 6-12 months, should be performed preoperatively to rule out another primary source.Ultrasound color flow can detect abnormal blood vessels as small as 1 mm diameter if the velocity is greater than 1 cm/s.While helpful and despite he theoretical aspects, color Doppler sonography is not always 100% reliable in differentiating benign versus malignant ovarian masses. Misdiagnosis may occur in benign inflammatory masses, metabolically active benign neoplasms, and corpus luteum cysts because of their increased and abnormal vascularization.The tumor marker CA125 may assist in evaluation, although its limitations must be understood. Sustained elevation of CA125 levels occurs in more than 80% of patients with non-mucinous epithelial ovarian carcinomas but in only 1% of the general population. Levels of CA125 in serum also may be elevated in patients with conditions such as endometriosis, leiomyomata, pelvic inflammatory disease, hepatitis, congestive heart failure, cirrhosis, and malignancies other than ovarian carcinomas.In postmenopausal patients with pelvic masses, CA125 levels in serum > 65U/mL are predictive of a malignancy in 75% of cases. Elevated levels of CA125 in serum in these patients should therefore alert the physician to suspect ovarian, endometrial, or other gynecologic malignancies. Although increased specificity can be achieved using other tumor associated antigens, this is accompanied by a decrease in sensitivity and is not generally helpful for diagnosis. Other serum tumor markers may be helpful in the diagnosis of ovarian malignancies although they are not sufficiently specific or sensitive to be diagnostic.FNA cytology of ovarian lesions is an acceptable method of diagnosis in a variety of clinical settings in women of reproductive and postmenopausal age groups. Ovarian FNA is indicated in young women, in whom preservation of ovarian function is desired. Even during pregnancy, FNA can be used safely to differentiate functional (follicular and luteal and other benign cysts of the ovary from those of neoplastic origin. Among the many variables influencing the accuracy of aspiration cytology of the ovary, the most important are the skill of the clinician performing the procedure and the experience of the pathologist interpreting the results. However, negative cytology does not preclude the need for further diagnostic procedures.The role of laparoscopy in diagnosis of ovarian cysts and tumors is controversial. If in the enlarged ovary appears being by physical examination, TVS, and serum CA125 testing and if the patient gives informed consent, then laparoscopic surgery may be considered because of a low risk of ovarian malignancy.ليس هناك دليل علي أن اختبارات المسح علي وجود أورام المبيض الخبيثة والتى تشمل التاريخ المرضي، الفحص الحوضي، دلالات الأورام CA125 الموجات الصوتية تقلل من معدلات الوفاة بسرطان المبيض. بالإضافة إلي أن هذه الاختبارات غير كافية لتوضح أن الاكتشاف المبكر سوف يقلل من معدلات حدوث الوفاة من هذه المرض.من المعروف أن معدل الإصابة بأورام المبيض الخبيثة في العالم قليل جداً حيث يمثل حوالي ”17 حالة لكل 100000 سيدة” لذلك فإن اختبارات المسح علي وجود أورام المبيض الخبيثة يعتبر مجال ضيق جداً. ومن الصعوبات ايضاً أن معظم السيدات ذات نتائج اختبارات المسح الإيجابية لا تعاني حقيقة من أورام المبيض الخبيثة ولكن هذه النتائج تمثل نتائج إيجابية كاذبة غير أن قيمة النتائج الإيجابية المبدئية لاختبارات المسح تزداد قوة في السيدات اللاتي يحملن عوامل خطورة للإصابة بالمرض مثل السيدات اللاتي يحملن تاريخ مرض أسري للإصابة بالمرض.الأورام الخبيثة للمبيض ذات أهمية كبيرة جداً. فهي تمثل أعلي معدلات وفاة من كل الأورام الخبيثة الأخري التى تصيب الجهاز التناسلي الأنثوي. حيث أنه من خلال الاحصائيات الحديثة حوالي 26.500 حالة يتم تشخيصها سنوياً في الولايات المتحدة الأمريكية حوالي 14.500 حالة وفاة تحدث منها. وهذه النسبة تمثل 5% من كل الأورام الخبيثة التى تصيب السيدات.يعتبر سرطان المبيض المبكر مرض كامن (غير عرضي) حيث أن حوالي 75% منه تكتشف منتشرة عند التشخيص المبدئ لها.أسباب أورام المبيض الخبيثة تعتبر غير معروفة ولكن هناك عوامل عديدة قد تزيد أو تقلل الإصابة بالمرض. تقدم السن،عدم الإنجاب، العقم، الأورام الخبيثة للرحم أو الثدي، التاريخ المرضي الأسري لأورام المبيض كل هذه العوامل قد تزيد من إحتمالية الإصابة بالمرض. علي الجانب الأخر الإنجاب الأدوية المستخدمة في نوع الحمل، الرضاع، ربط الانابيب، استئصال الرحم كل هذه العوامل قد تقلل من الإصابة بالمرض.السيدات اللاتي يمتلكن تاريخ مرضي أسري للأورام الخبيثة للمبيض أو الثدي وأيضا اللاتي لا يستطعن إكمال القدرة الإنجابية قد ينصحن بالاستئصال الوقائي للمبيض والقنوات علي الجانبين. وهؤلاء السيدات لابد أن يعلمن أن استئصال المبيض والقنوات علي الجانبين لا يوفر حماية بنسبة 100% من الإصابة بالأورام الخبيثة للمبيض حيث أن في بعض الحالات يوجد أورام أولية بالغشاء البريتوني للبطن.الاختبارات الوراثية من الممكن أن تحدد السيدات اللاتي يحملن تغيرات في الشفرة الوراثية وبالتالي يحملن عوامل خطورة عالية للإصابة بالمرض وهذا ويجعلنا بالضرورة تجنب الجراحة في الحالات التى لا تحمل هذه التغيرات.ليس هناك أعراض مبكرة للأورام الخبيثة للمبيض ولكن معظم الأعراض تشمل وجود ورم بالبطن أو انتشار الورم علي الجدار الخارجي للأمعاء أو وجود استسقاء بالبطن.التقيم المبدئ للمريض والذي يشمل التاريخ المرضي، الفحص، الموجات الصوتية من خلال المهبل يستطيع أن يفرق بين معظم الأورام الحميدة والأورام الخبيثة للمبيض.هناك عوامل متعددة تحدد بالموجات الصوتية وتستطيع أن تفرق بين الأورام الحميدة والأورام الخبيثة للمبيض. فالعوامل التى قد تزيد من احتمال وجود الأورام الخبيثة تشمل وجود مكونات صلبة ومكونات متكيسة بالورم أو وجود الورم علي الناحيتين أو وجود فواصل سميكة بالورم أو وجود سوائل بالتجويف البريتوني.دلالات الأورام من الممكن أن تساعد في تشخيص أورام المبيض الخبيثة ولكن في حدود معينة حيث أنها قد ترتفع معدلاتها أيضا في حالات أخري مثل أورام العضلات الحميدة، الالتهابات المزمنة للحوض، تليف الكبد، التهابات الكبد، فشل القلب وبعض الأورام السرطانية الأخري.التحليل الخلوي للسائل المأخوذ بالابره الدقيقة من أورام المبيض يعتبر من طرق التشخيص أيضا خصوصاً في السيدات صغيرات السن واللائي يردن الحفاظ علي وظائف المبيض. وأيضا يمكن استخدام هذه الطريقة اثناء الحمل. ودقة هذه الطريقة تحدد بمهارة الطبيب الذي يأخذ العينة.هناك اختلاف حول استخدام منظار البطن الجراحي في تشخيص تكيسات وأورام المبيض الخبيثة.وفي النهاية ولان معظم حالات أورام المبيض الخبيثة تكتشف في مراحل متأخرة فإن العلاج بالتالي في معظم الحالات يكون غير جذري أي مجرد علاج تحفظي.
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