Metastatic patterns of epithelial ovarian cancer:
- Lymphatic to lymph nodes in the pelvis and along the aorta
- Via blood to the liver and/or lungs
- Can spread to pleura
There is often early intraperitoneal spreading in epithelial ovarian cancer via release of malignant cells from the ovarian surface, thereby spreading with fluid to the abdominal cavity, attaching to the abdominal membrane and growing as metastases. The ovaries can therefore have a normal or nearly normal size, even when there is extensive intraperitoneal metastasis. Extensive intraperitoneal disease will usually give rise to symptoms.
Borderline tumors are usually diagnosed in stage I (85%), while 5% are in stage II, and 10% in stage III. The tumors are usually unilateral with 65% in stage Ia, 14% in stage Ib and 6% in stage Ic. Even though it is a characteristic of borderline tumors that they do not infiltrate the capsule, it is still possible, with involvement of the ovarian surface and further spread to the abdominal cavity. These tumors do not spread to lymph nodes and do not metastasize outside the abdominal cavity.
In fallopian cancer, metastasis occurs primarily by release of malignant cells from the tumor in the tube(s), which spread via fluid in the abdominal cavity, attach to the abdominal membrane and grow as metastases. These tumors have a prominent tendency to spread to lymph nodes, therefore, it is always recommended to remove the lymph nodes in the pelvis and along the aorta in cases where all tumor tissue can be removed by surgery.
Primary peritoneal carcinoma
This form of tumor originates from the abdominal membrane's coelomic epithelium, and is thus primarily diffuse throughout the entire abdominal cavity. Extraperitoneal metastatic patterns are as in ovarian cancer.