The relationship between tumor size and stage in early versus advanced ovarian cancer

Ovarian cancer has a different prognosis between early (I and II) and advanced stage (III and IV). The mechanism of disease progression is unknown, but patients with advanced disease may have a higher propensity for seeding of the abdominal cavity early in the disease process than those with early stage. Theoretically if this is so, then patients with advanced stage should have smaller sized tumors than patients with early stage.

This was a retrospective chart review of patients in the tumor registry in 2003-2006. Patients had epithelial ovarian cancer, other cell types were excluded. Only cases with documentation of surgical and pathologic staging and measured dimensions on pathologic specimen were included. Patient stage and all available dimensions measured on diseased ovaries were recorded. The dimensions for each patient were averaged into a single dimension for that patient, and then these measurements were totaled and averaged.

There were 110 patients analyzed: 85 with advanced disease, 25 with early stage. The average measurement was 4.8 cm in advanced disease, and was 10.7 cm in early stage disease. This difference was statistically significant (p<0.001).

Overall, patients with early stage ovarian cancer have diseased ovaries that are more than twice as large as those found in advanced disease. This finding supports the fact that early versus advanced ovarian cancer are 2 separate disease processes. Early stage grows locally and does not disseminate, and advanced stage disseminates while the tumor is still relatively small. Theoretically there may be a factor that separates these 2 into different diseases, where advanced disease patients have a substance produced by their tumor that allows for early dissemination, and early stage lacks this substance and only grows locally. Basic science research comparing the tissue microarrays of early versus advanced stage disease may be able to identify this difference. If the difference is found, perhaps therapy can be targeted against this difference, and screening tests for advanced ovarian cancer can be improved.