OVARIAN GERM CELL TUMORS
Jeffrey L. Stern, M.D.
Germ cell tumors account for approximately 5 percent of all ovarian malignancies. They almost always occur in women of reproductive age and are most frequently found in women in their teens or twenties. Many types of germ cell tumors are extremely aggressive, fast-growing malignancies. In the past they were often fatal within two years even though frequently confined to one ovary at the time of diagnosis. With surgery and modern multi-agent chemotherapy, the cure rate is excellent.
There are six main cell types: dysgerminoma, endodermal sinus tumor, embryonal carcinoma, choriocarcinoma, immature teratoma and mixed germ cell tumors.
There are also rare cell types such as struma ovarii, carcinoid and malignant transformation of a benign dermoid.
How It Spreads
Ovarian germ cell tumors can spread directly to the adjacent pelvic organs and through the lymph system to the pelvic, aortic, chest (mediastinal), groin and neck lymph nodes. They may also spread to the surfaces of the abdominal cavity and to distant organs such as the liver, lungs and brain.
What Causes It
The cause is not clear.
At Significantly Higher Risk
SCREENINGNo definitive screening method is available, except for a routine annual pelvic, abdominal and rectal examination.
COMMON SIGNS AND SYMPTOMS
These tumors often do not cause any symptoms. Some women, however, will have a rapidly enlarging pelvic or abdominal mass and vague pain in the lower abdomen. Other women can experience abnormal vaginal bleeding or acute abdominal symptoms, including pain and shock.
Blood and Other Tests
Endoscopy and Biopsy
The International Federation of Gynecology and Obstetricians (FIGO) staging classification for malignant epithelial carcinomas of the ovaries is also used for staging malignant germ cell tumors of the ovary. Germ cell tumors of the ovary are surgically staged.
Cancer is confined to one or both ovaries.
The cancer involves one or both ovaries with extension to other pelvic structures.
The tumor involves one or both ovaries with tumor present outside the pelvis or there is cancer in the abdominal or groin lymph nodes.
There are distant metastases to the liver or lungs or there are malignant cells present in the fluid accumulated in the chest cavity.
Surgical removal of the involved ovary or ovaries and removal of as much of the grossly visible tumor as possible is performed in all cases. If there is no spread beyond the ovaries, treatment will involve meticulous surgical staging, including removal of the pelvic and para-aortic lymph nodes, washings of the abdominal cavity to look for malignant cells and careful inspection of the abdominal surfaces with multiple, random biopsies from the diaphragms and surfaces of the abdominal cavity. An omentectomy (removal of fatty tissue attached to the stomach and large intestine) will also be performed. Recently, laparoscopic minimally invasive surgery has been performed in selected cases with similar results.
The cell type of the tumor is an extremely important factor in determining the prognosis and the appropriate therapy after surgery.
Women with a tumor confined to one ovary (Stage I) or with a well-differentiated (Grade 1) immature teratoma or dysgerminoma do not require postoperative chemotherapy. All others are usually treated with multi-drug chemotherapy.
Until recently, external radiation therapy to the abdomen and pelvis with a boost to the para-aortic node region was standard therapy for dysgerminomas, but chemotherapy is now used more often to preserve fertility.
Women with other malignant germ cell tumors are treated with chemotherapy after surgery because radiation therapy is ineffective. The most commonly used chemotherapeutic drug regimen includes cisplatin and etoposide with or without bleomycin given monthly for three or four courses.
Occasionally, in women with Stage II, III or occasionally IV disease who have no evidence of persistent cancer after chemotherapy, "second-look" exploratory abdominal surgery is performed to see if they are truly disease-free.
Second-look surgery is not usually performed on correctly staged women with well-differentiated immature teratomas, Stage Ia and Ib dysgerminomas or other Stage I germ cell tumors who had elevated alpha-fetoprotein, hCG or LDH levels before treatment that returned to normal with chemotherapy.
Women who have bulky disease after chemotherapy may occasionally benefit from a tumor debulking at a second surgery.
TREATMENT BY STAGE AND CELL TYPES
Standard Treatment The involved ovary and fallopian tube and a wedge biopsy of the opposite, normal-appearing ovary and meticulous surgical staging is performed in women who want to preserve their fertility. Women with Stage Ia disease require no further treatment.
About 20 percent of women will have microscopic disease in the opposite, apparently normal ovary (Stage Ib). For women who do not desire more children or who are approaching menopause, a hysterectomy and removal of both tubes and both ovaries is performed.
Standard Treatment Women with this stage of disease are usually treated with three courses of cisplatin, etoposide with or without bleomycin or whole-abdominal radiation therapy after hysterectomy, removal of both fallopian tubes and ovaries and meticulous staging.
Standard Treatment After surgery most gynecologic oncologists recommend three courses of cisplatin, etoposide with or without bleomycin or less commonly whole-abdomen radiation therapy.
STAGES II, III, and IV
Standard Treatment Depending on the extent and location of disease, standard therapy includes a hysterectomy, removal of both tubes and both ovaries, aggressive tumor debulking and at least three courses of cisplatin, etoposide with or without bleomycin. The opposite ovary and uterus can be preserved, if normal, in women who want to maintain their reproductive capacity. Whole-abdomen radiation may be given to those women who fail to respond to chemotherapy or who are not interested in preserving their reproductive function.
Investigational Same as Stage Ib.
NON-DYSGERMINOMATOUS GERM CELL TUMORS
These include endodermal sinus tumors, embryonal carcinoma, immature teratoma, choriocarcinoma and mixed germ cell tumors.
Standard Treatment Removal of the affected tube and ovary and surgical staging are generally all that is required since these tumors rarely occur in both ovaries.
Postoperative chemotherapy including cisplatin, etoposide with or without bleomycin is given to all patients with the exception of Grade 1 (well-differentiated) immature teratomas, for three or four courses.
STAGES II, III, and IV
Standard Treatment Depending on the extent and location of disease,a hysterectomy, bilateral removal of the tubes and ovaries, and aggressive tumor debulking is usually performed. If the opposite ovary and uterus are normal, they can be preserved in women who want to maintain their reproductive function. Four courses of chemotherapy including cisplatin, bleomycin and etoposide are given after surgery.
FIVE-YEAR SURVIVAL RATES
The five-year survival rate for Stages Ia and Ib dysgerminomas and Grade 1 immature teratomas is over 95 percent. Even women with Stage III dysgerminomas have approximately an 80 percent survival rate.
Survival rates for women with Stages I and II non-dysgerminomatous germ cell tumors are greater than 90 percent. Women with Stage III and IV disease have survival rates estimated to be greater than 75 percent.
All women with germ cell tumors need careful follow-up every three months for the first two years after treatment.
Germ cell tumors may recur in the pelvis, the abdominal cavity, liver,lungs and lymph nodes. Symptoms may include pelvic or abdominal pain, bleeding, nausea, vomiting, abdominal swelling, weight loss and chronic cough.
THE MOST IMPORTANT QUESTIONS YOU CAN ASK
See additional online resources for information on Ovarian Cancer.
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