Ovarian cancer is the leading cause of death due to gynecological malignancies in this country. It is the fifth most common cause of cancer death in women. Historically, all ovarian cancers have been grouped together as one disease, though they may actually be a much more diverse disease.
Morphologically, these epithelial ovarian cancers have been separated by histologic cell types:
About 70% of epithelial ovarian cancers are of the high grade serous type. In addition, 50% of the high grade serous carcinomas have the BRCA genetic markers.
Malignancies of the fallopian tubes have always been considered very rare. Newer information now suggests a key role for the fallopian tube in the development of ovarian cancer. The distal end of the fallopian tube may be the site of origin for the most common type of ovarian cancer.
This conclusion is derived from the following observations:
A study done with young women identified as being positive for the BRCA1 or BRCA2 gene also offers more insight. The women were divided into two groups. One group waited until the age of 40 and had a bilateral salpingo-oopherectomy done (remove both tubes and ovaries) to help prevent the development of ovarian cancer. The second group had both tubes removed at an earlier age, then returned to the operating room at the age of 40 to remove both ovaries. The reason that the ovaries were not removed until age 40 is in part due to the fact that ovarian cancer seems to peak in the 4th and 7th decades of life and patient’s did not want to be forced into menopause any sooner. The second group however, had finished their family and had the fallopian tubes removed earlier (based on the possible belief that the fallopian tube was the true precursor of ovarian cancer). Results confirmed a significant decline in ovarian cancer in the second group that underwent a two stage procedure of removing their tubes first, the ovaries at a later date.
More studies are being done to help confirm this new evidence that many ovarian cancers might actually be a later stage of fallopian tube cancer. In British Columbia, Canada, a study is ongoing in which doctors are being asked to do a complete salpingectomy-bilateral (remove both tubes) instead of a simple tubal ligation when permanent contraception is desired. In addition, all hysterectomies are including bilateral salpingectomies (remove both tubes) regardless of whether the ovary is to be removed or left in place. In the past, if the ovaries were being left in the pelvis at the time of a hysterectomy, the tube would also be left in place with the ovary. This was done in hopes of not disturbing the blood supply to the ovary so that they would function better post operatively. The hope is that these studies will confirm a significant decline in ovarian cancer and thus offer a new treatment paradigm for this disease.
With all of this new information, one must strongly consider removal of the fallopian tubes at the time of hysterectomy, irregardless of whether the ovaries are to be removed or left in place in hopes of reducing ovarian cancer in the future.