Gynecologic Oncologists
Take the right treatment path.
The need for a breakthrough in
the ability to predict ovarian
cancer malignancy is critical.
Ovarian cancer is the leading cause of death from gynecologic cancers in the United States and the fifth leading cause of death from cancer in women.4 It accounts for 4% of all female cancers and 31% of cancers of the female genital organs. Each year, there are an estimated 22,000 new cases in the United States. Women who are postmenopausal are at the greatest risk for ovarian cancer.5 In their lifetimes, 1 in 69 women will develop ovarian cancer.6
Because the symptoms of ovarian cancer are mild, it is hard to detect early. In fact, approximately 75% of cases are first diagnosed at an advanced stage (stage III or IV). Overall, prognosis for these patients continues to be poor and is closely related to the stage at which they are diagnosed.
Optimal Management of Ovarian Malignancy
Approximately 20% of women will develop an ovarian cyst or pelvic mass in their lifetimes, and many of these women will undergo unnecessary surgery. When ovarian cancer is suspected due to a pelvic or ovarian mass, a diagnostic and staging laparotomy should be conducted. Routine tests prior to surgery include a chemistry panel, CBC count, and other diagnostic tests.
If no determination can be made based on the diagnostic tests, then an ultrasound should be performed to aid in the detection of any cysts or tumors. Standard treatments for ovarian cancer include debulking surgery, chemotherapy, and radiation. Two or all of these treatments may be recommended, depending upon each individual case.
The primary goals of ovarian cancer surgery are to stage the cancer and determine how far beyond the ovary it has spread, as well as to remove as much of the tumor as possible. Staging is important because it determines the course of treatment.
Cancer Staging
Cancer staging is central to the treatment and management of cancer patients. The International Federation of Gynecology and Obstetrics (FIGO) system is the staging system used most often because it is accepted worldwide and supports an international standard. FIGO staging for ovarian cancer is18
- Stage I—Growth limited to the ovaries
- Stage Ia—Growth limited to one ovary, no ascites, no tumor on external surface, capsule intact
- Stage Ib—Growth limited to both ovaries, no ascites, no tumor on external surface, capsule intact
- Stage Ic—Tumor either Stage Ia or Ib but with tumor on surface of one or both ovaries, ruptured capsule, ascites with malignant cells, or positive peritoneal washings
- Stage II—Growth involving one or both ovaries, with pelvic extension
- Stage IIa—Extension and/or metastases to the uterus or tubes
- Stage IIb—Extension to other pelvic tissues
- Stage IIc—Stage IIa or IIb with tumor on surface of one or both ovaries, ruptured capsule, ascites with malignant cells, or positive peritoneal washings
- Stage III—Tumor involving one or both ovaries, with peritoneal implants outside the pelvis and/or positive retroperitoneal or inguinal nodes; superficial liver metastases equal Stage III
- Stage IIIa—Tumor grossly limited to pelvis, negative lymph nodes but histological proof of microscopic disease on abdominal peritoneal surfaces
- Stage IIIb—Confirmed implants outside of pelvis in the abdominal peritoneal surface; no implant exceeds 2 cm in diameter, and negative lymph nodes
- Stage IIIc—Abdominal implants larger than 2 cm in diameter and/or positive lymph nodes
- Stage IV—Distant metastases; pleural effusion must have a positive cytology to be classified as stage IV; parenchymal liver metastases equals stage IV
Chemotherapy
Standard chemotherapy after surgery is combination therapy with platinum and paclitaxel. Cisplatin and paclitaxel or carboplatin and paclitaxel are accepted alternatives. Although randomized studies have shown that both regimens result in equivalent survival rates, the combination of carboplatin and paclitaxel is preferred, due to a more favorable toxicity profile. If patients are treated with cisplatin, then paclitaxel should be administered as a 24-hour infusion to decrease the risk of neurotoxicity. Another option is to combine carboplatin with docetaxel.
CA125™ is the most widely used tumor marker worldwide for ovarian cancer and is indicated for use as an aid in the detection of residual ovarian carcinoma in patients who have undergone first-line therapy and would be considered for diagnostic follow-up procedures.
Intraperitoneal Chemotherapy
Results from 3 randomized clinical trials indicate intraperitoneal (IP) administration of chemotherapy (cisplatin) is superior to intravenous (IV) administration in patients with optimally debulked tumors. However, this approach also results in greater toxicity. The National Cancer Institute released a clinical announcement supporting the use of IP chemotherapy in optimally debulked ovarian cancer.
Neoadjuvant Chemotherapy
Patients who are not appropriate candidates for surgical cytoreduction but have an advanced stage of ovarian cancer may be treated initially with 2 to 3 cycles of conventional chemotherapy, after which they should be reassessed for surgical cytoreduction. However, initial cytoreduction remains the ideal therapy for most patients.
Maintenance Chemotherapy
The majority of ovarian cancer patients achieve a complete clinical response following surgery and chemotherapy. However, many will face recurrence and ultimately succumb to the disease. In response to this, therapies that may decrease the risk of recurrence have been investigated. A phase III randomized trial reported an improvement in disease-free survival in patients treated with 12 cycles of maintenance paclitaxel.
Second-line Chemotherapy
Many ovarian cancer patients face recurrence. Following chemotherapy, patients can be classified into one of 2 categories:
- platinum-sensitive (relapse >6 months after initial chemotherapy)
- platinum-resistant
Clinical trial results indicate combination chemotherapy offers improved response rates, progression-free survival, and overall survival.
Even with the most recent advances, the need for a breakthrough in the ability to predict ovarian cancer malignancy is critical. Additionally, detection of a greater percentage of cancers in the early stages may improve outcomes.17
