Ovarian cancer is one of the leading causes of women’s deaths. The peak incidence of ovarian cancer is in late 50′s, while malignant germ cell cancer (one type of ovarian cancer) occurs in early 30′s. When abnormal cells divides too fast a cellular mass or tumor is formed which doesn’t invade to surrounding and are within a cell, this is called benign tumors and if the tumor spread to surrounding tissue or organ it is called malignant or cancerous and the process in with this cells invade surrounding is called metastasis.
Types of Ovarian Cancer:
There are 3 main types of ovarian cancer; primary epithelial cancer, Germ cell tumors and Sex cord tumors. Primary epithelial cancers comprise of 80-90% of all ovarian cancer and are classified into six histological types, of which Serous and Endometrioids are more common.
- Serous (fallopian tube) – 40%
- Endometrioid (endometrium) -24%
- Mucinous (cervix)
- Clear cell (mesonephros)
- Transitional cells
- Undifferentiated carcinoma
Germ cell tumors include endodermal sinus malignancies, embryonal carcinoma (a rare ovarian cancer that appears in children), immature teratomas, and dysgerminoma.
Sex cord (stromal) tumors include granulosa cell tumors (that produce estrogen and may have feminizing effects), granulosa-theca cell tumors, and the rare arrhenoblastomas (that produce androgen and have virilizing effects).
Causes and Risk Factors of Ovarian Cancer:
It is still unknown the real cause of ovarian tumors. However studies suggest that several factors including, hormonal, environmental, and genetic variables may play a role in causing ovarian cancer. Some of the risk factors are discussed below:
Family history of ovarian cancer:
Woman has as high as a 50% risk of getting ovarian cancer if two or more first-degree relatives (mother, sister, and daughter) have history of ovarian cancer. However women have less risk for second-degree relatives (grandmother, aunt, cousin).
The risk of developing ovaries cancer increase with increase age. Its incidence is high in late 50′s. Over 50% of cancer occurs in women older than 60 years.
Menstrual history/pregnancy history:
The risk of developing ovaries cancer is high in early menarche (less than 12 yrs) and late menopause (greater than 50 yrs). Late first child birth(after 35 yrs) may also be associated with risk of developing cancer.
Women who have breast cancer or other cancer have high risk of ovarian cancer then women who had not any previous cancer.
Some have suggested that women who apply talcum powder to the genital area or sanitary napkins have higher risk of developing ovarian cancer.
High fat diet is also linked in causing cancer, especially obesity is involve in risk of causing cancer.
Hormone replacement therapy (HRT):
There are some evidence that women who receives HRT after menopause have slightly increase risk for cancer but only with high dose and long-term use.
Other Risk factors of ovarian cancer may be repeated radiography of pelvis, late menarche and artificial menopause.
Acquired genetic mutations:
Researcher have suggested that genetic mutations of DNA alter oncogenes (genes that promote cancer cell division) tumor suppressor genes(cancer preventing genes) and other genes may results in high risk for ovarian cancer. Acquired mutations of the HER2 oncogene or the p53 tumor suppressor gene may be associated with a higher risk of ovarian cancer.
Ovarian Cancer Symptoms and Signs
Despite the common beliefs that early stage ovaries cancer is with out symptoms most women with ovaries cancer have vague symptoms such as lower abdominal pain abdominal distention and epigastric discomfort. The important sign being, pressure of pelvic mass during physical examination. If the cancer has metastasis to surrounding or has advanced then other symptoms like anorexia, fatigue, nausea, weight loss may be seen. So signs and symptoms of ovarian cancer may include the following:
- Abdominal or pelvic discomfort or pressure
- Back or leg pain
- Changes in bowel function or urinary frequency
- Fatigue, nausea, vertigo
- Gastrointestinal symptoms (gas, long-term stomach pain, indigestion)
- Abnormal vaginal bleeding
- Feeling of fullness after a light meal
With only the symptoms it is not possible to diagnose the disease. There are more clinical lab, radiology and cytology findings which helps to confirm the disease. It requires detailed patient history, clinical evaluation, surgical exploration and some histological studies. Any enlargement of the ovary in post menopausal women is regarded as malignant cancer until proved. Laboratory tumor marker studies, such as Ca-125, human chorionic gonadotropin and carcinoembryonic antigen may be helpful to differentiate between benign or malignant process, although the marker may be negative in half of early stages of ovarian cancer. Abdominal and pelvic Ultrasonography or CT may help to determine the size of tumor. It may still be difficult to determine the benign or malignant nature of cancer until laparotomy.
Surgical exploration with biopsy will confirm the diagnosis of the disease. Abdomen is opened and explored and the tissue from the site is taken out for pathology studies.
Treatment of Ovarian Cancer:
Accurate pathologic evaluations and thorough surgical staging are essential to the management of early stage disease. In girls or young women who have unilateral encapsulated tumors and wish to maintain their fertility, resection of the ovary involved with consideration of later removal of another ovary after child bearing is suggested
For the patient who doesn’t like to have more child, Total Abdominal Hysterectomy with Bilateral Salpingo Oophorectomy can be done. Patients with stage Ia grade 1 or grade 2 tumors have very good prognosis and may not require additional chemo therapy.
Chemotherapy is very effective in ovarian cancer as adjuvant therapy and in achieving clinical remission. The current regimen for advance epithelial ovarian cancer is a combination of taxane and carboplatin and for germ cell tumors is cicplatin, etoposide and bleomycin.
Ovarian Cancer Prevention and Screening
The most important is by avoiding the risk factors which we have discussed above. Bilateral salpingo-oophorectomy at the time of hysterectomy in women over age 50 and after child bearing function has completed in younger women is advocated by many in prevention of development of ovarian cancer. No effective screening test for ovarian cancer is applicable to general population though women with strong family background should be considered for genetic counseling.
Known protective factors for ovarian cancer includes, child bearing and use of oral Contraceptive pills. Even 6 months of pills use seems to decrease the relative risk for ovarian cancer and the effect remains protective for up to 10 years. For patient with genetic mutation predisposing them to increase risk, prophylactic oophorectomy may be performed with or without prophylactic mastectomy for breast as well.