In this blog, I will start to discuss the different types of diseases of the ovary and will go over some of the more common types of cysts of the ovary that can be part of the normal menstrual cycle. A diseased ovary will have an abnormal growth either, liquid (a cyst), solid (tumor), or a growth comprised of a mixture of solid and liquid (complex mass). These conditions can also be divided into cancerous (malignant), non-cancerous (benign) or borderline tumors. When reading about these conditions you may see the word “adnexa” used, which refers to the fallopian tube and the ovary, thus the right adnexa is the right tube and ovary.
A functional or follicular cyst of the ovary forms during the first two weeks of the menstrual cycle every month as the egg matures prior to ovulation. Normally the fluid in this cyst drains out with ovulation (when the egg is released from the ovary). The two weeks after ovulation prior to the first day of the next period, a corpus luteum cyst forms. Normally it is really not much of a cyst but does produce progesterone until the period starts. Occasionally when the egg is released a small vessel is ruptured and bleeds back into the cyst and is known as “Hemorrhagic Corpus Luteum” (HCL) cysts. In essence, it is a blood clot in the ovary, which can be moderately large (several centimeters in diameter) and sometimes can look similar to an ovarian endometrioma on an ultrasound (sonogram). Your physician may have you come back in 1 to 2 months to recheck the size of the cyst with the ultrasound. The HCL will go away (kind of like healing a bruise) but an endometrioma will not shrink in size.
A “simple cyst” means it is a single, smooth round fluid cyst. A simple cyst can be a follicular cyst. If a simple cyst does not go away with the period, it can be a follicular cyst that did not rupture (ovulate) or got “stuck” which can happen once in awhile in an otherwise normal ovary. Often these will resolve with some time. Occasionally it will need to be drained, which in this case often resolves the problem. A simple cyst on sonogram can also be a cyst on the fallopian tube. It is fairly common to have “para-ovarian cysts”. Usually, these are not very large, but occasionally may be confused with an ovarian cyst. Sometimes it is difficult to tell if the cyst is actually on the ovary or fallopian tube with an ultrasound.
In the next blog, I will go over the different types of benign ovarian tumors (not cancer) and the different types and subtypes of ovarian cancer. Ovarian cancer is not one disease but actually represents over 30 different types of cancer. After we have gone through some of the basics about the more common forms of ovarian cancer, we can start to talk about the relationship between endometriosis and the different types of ovarian cancer.