The likely course of ovarian cancer is predicted using prognostic factors. The only universally accepted prognostic factors for patients with ovarian cancer are stage and, in advanced stage patients, volume of residual disease. Other factors that may be important but about which there is continued debate include patient age, histopathologic grade, and DNA ploidy. Many other putative prognostic factors have been reported but the data are still considered preliminary. See also Peritoneal Fluid Cytology and CA125.|
The International Federation of Gynecology and Obstetrics (FIGO) has standardized the staging of gynecological cancers (see Staging). FIGO stage is so powerful a predictor of prognosis in ovarian cancer that most other putative prognostic factors are of little importance in comparison to stage. Staging takes both surgical and pathological findings into account, hence the term, "surgicopathologic stage".
Women with FIGO stage I ovarian carcinomas, if staged by current meticulous procedures by a gynecological oncologist, have an excellent prognosis. Stage I patients with grade I tumors have a 5-year survival of over 90%, as do patients in stages IA and IB. Poor prognostic factors in stage I include grade 3 histology and IC substage, both of which are associated with poorer survival rates. Although it is possible that the IC substage based on malignant cells in
or peritoneal washings is the first evidence of true metastatic ability, these cells may merely be exfoliated. Most stage IB cases are serous and probably reflect independent primary tumors.
Stage II ovarian cancer is a small and heterogeneous group, and comprises 10% of ovarian cancers. It is defined as extension or metastasis to extraovarian pelvic organs, most commonly the fallopian tubes and pelvic peritoneum.
Ovarian cancer most commonly presents in stage III, comprising 51% of cases. These tumors characteristically spread along peritoneal surfaces involving both pelvic and abdominal peritoneum. Metastases to retroperitoneal lymph nodes commonly occur, and inguinal lymph nodes less commonly, and indicates stage IIIC even in the absence of peritoneal metastases, a rare occurrence.
Stage IV includes patients with parenchymal liver metastases and extra-abdominal metastases. Thirteen percent of patients present in stage IV. Among these, liver and lungs are the most common metastatic sites. During the course of the disease, one-third of all ovarian cancer patients have pleural effusions, and three-quarters of these contain malignant cells. Metastases occur in the spleen on occasion and may necessitate splenectomy. Brain metastases are present in 0.1% of patients at presentation.
Peritoneal Fluid Cytology
Cytological samples of peritoneal fluid are routinely obtained during staging procedures for ovarian cancer. These findings are important in substaging early (FIGO I and II) ovarian cancer; malignant cells in peritoneal washings or ascites warrants assignment of tumors to stage IC or IIC.
At present, grading of ovarian carcinoma is clinically important only for stage I patients because chemotherapy is withheld for low grade tumors in view of their outstanding prognosis when untreated. Most proposed grading systems are three grade systems and are unlikely to be reproducible. Since the decision is to treat or not to treat, we believe that ovarian carcinomas should be classified either into either low grade or high grade, with chemotherapy withheld for low grade stage I cases.
Volume of Disease
Volume of residual disease is an important prognostic factor in most studies. This is supported by the demonstrated value of cytoreductive surgery, both primary and secondary, in prolonging survival and progression-free interval. Data are conflicting on tumor rupture and capsular penetration. Although either of these findings warrants reassigning of an otherwise stage I or II tumor to IC or IIC, the prognostic value of these features is unclear.
Serum levels of CA125 correlate with volume of disease. Although high preoperative CA125 levels may predict unresectability and poor survival, postoperative CA125 levels appear to be more prognostic. Some investigators believe that although CA125 levels may be useful predicting group outcomes, they lack the power to guide individual treatment decisions. More about CA125 ....
The prognostic utility of DNA flow and image cytometry are controversial. Much of the published data are conflicting. In addition, there are significant reproducibility problems, as well as many other methodological and interpretive issues. Image cytometry is very labor-intensive. At present, these techniques remain investigational.