Ovarian cancer is a malignancy that can originate in the ovaries, fallopian tubes, or the peritoneum (the lining of the abdomen). This cancer is often diagnosed in later stages because its early symptoms are vague and easily mistaken for less serious conditions. While many people worry about abnormal bleeding, it is important to recognize that bleeding is not the most frequent warning sign of this disease. This article clarifies the frequency and nature of bleeding related to ovarian cancer and highlights the more common symptoms patients should monitor.
Frequency and Type of Bleeding
Abnormal vaginal bleeding is not considered a common or early symptom of ovarian cancer, unlike other gynecologic cancers. Studies suggest that only a minority of ovarian cancer patients, potentially around 7.7% in one population cohort study, report vaginal bleeding. This low frequency means that most people with ovarian cancer will never experience this symptom.
When bleeding does occur, it is often unusual in timing or flow. For post-menopausal individuals, any vaginal bleeding is considered abnormal and requires immediate medical attention. For those who are pre-menopausal, bleeding may manifest as intermenstrual spotting, unusually heavy periods, or irregular cycles. Bleeding after sexual intercourse is another form of abnormal bleeding sometimes associated with ovarian cancer.
Understanding the Cause of Bleeding
When ovarian cancer causes bleeding, the mechanism relates to the type of tumor or its physical effect on surrounding organs. A small percentage of ovarian cancers, specifically sex cord-stromal tumors (about 1% of all ovarian cancers), are hormonally active and produce hormones like estrogen.
This excess estrogen stimulates the lining of the uterus (the endometrium), causing it to thicken. The subsequent shedding of this thickened lining leads to abnormal uterine bleeding, which can resemble a period, even in post-menopausal people. More commonly, large ovarian masses press on or irritate the uterus or cervix, causing superficial erosion and a non-hormonal source of bleeding. This physical pressure is generally seen in more advanced stages.
The More Common Symptoms
Since bleeding is an infrequent symptom, patients should focus on recognizing the more common, non-specific signs of ovarian cancer. These symptoms often involve the gastrointestinal and urinary systems due to the tumor’s location in the pelvic and abdominal cavity. The most frequently reported symptoms include persistent bloating and a noticeable increase in abdominal size. This abdominal swelling can be caused by the tumor itself or by fluid buildup in the abdomen, known as ascites.
Other common symptoms include feeling full quickly after eating or experiencing a loss of appetite. Patients may also notice changes in urinary habits, such as needing to urinate more often or with greater urgency. Pelvic or abdominal pain that is new and persistent is another frequent symptom, sometimes described as similar to menstrual cramps. These symptoms, including back pain, constipation, and fatigue, are concerning when they occur almost daily and represent a change from a person’s normal state.
Importance of Timely Diagnosis
The difficulty in diagnosing ovarian cancer early stems from the vague nature of its symptoms and the infrequency of bleeding. When ovarian cancer is found at its earliest, localized stage, the five-year survival rate is significantly higher, close to 93%. However, only about 20% of cases are diagnosed at this early stage.
The key to timely diagnosis is recognizing the persistence of symptoms, specifically those occurring more than 12 times per month for a few weeks. If symptoms like persistent bloating or pelvic pain do not resolve with typical interventions, such as diet changes, a medical consultation is necessary. A doctor may then order specific tests, such as a transvaginal ultrasound to visualize the ovaries and a CA-125 blood test, to investigate the cause of the persistent symptoms.