Recognizing Borderline Ovarian Tumor Symptoms: Signs You Shouldn’t Ignore

Borderline ovarian tumor symptoms often fly under the radar until the tumors reach a significant size, making them challenging to detect in the early stages. 

Unlike aggressive ovarian cancers, these tumors occupy a middle ground — neither fully benign nor malignantly invasive — but they still demand attention and proper care. Let’s dive into the symptoms, why they matter, and what you should do if you suspect something isn’t right.

What Are Borderline Ovarian Tumors?

Borderline ovarian tumors (BOTs), sometimes called tumors of low malignant potential or borderline ovarian cancer, make up approximately 15% of all epithelial ovarian tumors. These non-invasive neoplasms show more controlled growth than invasive malignant tumors but can still spread within the peritoneal cavity.

What sets them apart is their excellent prognosis — the 5-year survival rate reaches 95 to 97% for stage I tumors. Unlike invasive ovarian cancer, borderline tumors typically affect younger women, with the average age at diagnosis being about 45 years, which is roughly 10 years younger than those diagnosed with invasive ovarian cancer.

Common Symptoms of Borderline Ovarian Tumors

Many people with borderline ovarian tumors experience no symptoms whatsoever, especially when the tumors are small. Approximately 23% of patients remain asymptomatic, with their tumors discovered incidentally during unrelated medical exams or procedures.

When symptoms do appear, they often include:

• Abdominal pain or pressure: Often described as a feeling of fullness or pressure rather than sharp pain
• Abdominal swelling or increased girth: You might notice your pants getting tighter around the waist
• Feeling full quickly when eating: A common symptom that’s easy to dismiss
• Pelvic discomfort: This may be persistent or intermittent
• Irregular periods or abnormal vaginal bleeding: Bleeding outside your normal menstrual cycle
• Painful intercourse: New or worsening pain during sex
• Changes in bowel habits: Constipation or more frequent bowel movements
• Increased urination frequency: Needing to pee more often than usual

The challenge with these symptoms is their non-specific nature. 

When Borderline Ovarian Tumor Symptoms Intensify

As borderline tumors grow larger, symptoms typically become more noticeable. Advanced borderline tumors might cause:

• More pronounced abdominal distension
• Visible abdominal mass
• More severe pain
• Difficulty eating normal portions
• Significant bowel or bladder pressure

In the case of larger mucinous borderline tumors, which can reach sizes of 20-22 cm (about the size of a cantaloupe or larger), the physical pressure on surrounding organs can cause more intense symptoms. These larger tumors can sometimes be felt during a physical examination.

Differences in Symptoms by Tumor Type

The two main types of borderline ovarian tumors — serous and mucinous — may present somewhat differently:

Serous Borderline Tumors:

• More commonly bilateral (affecting both ovaries)
• May cause more symmetrical abdominal swelling
• Often diagnosed at earlier stages due to bilateral symptoms

Mucinous Borderline Tumors:

• Typically unilateral (affecting one ovary)
• Grow larger before causing symptoms (average size 20-22 cm)
• May cause more pronounced one-sided abdominal swelling

Understanding these differences helps doctors determine which diagnostic tests to order when you present symptoms.

Learn more: Serous Borderline Tumor vs. Mucinous Borderline Tumor: What’s the Difference?

Why Symptoms Are Often Missed

There are several reasons why borderline ovarian tumor symptoms often go unrecognized.

The gradual onset of symptoms makes them easy to attribute to other causes. You might think your bloating is just from something you ate or normal hormonal changes.

Many symptoms mimic common digestive issues. That constipation or feeling of fullness might be dismissed as ordinary indigestion or irritable bowel syndrome.

Women may normalize abdominal discomfort or bloating. After all, occasional bloating is something many women experience regularly.

Younger women (who are more likely to develop BOTs) may not expect serious health issues. When you’re in your 20s or 30s, ovarian tumors are usually the last thing on your mind.

Some symptoms like increased urination or feeling full quickly can seem unrelated to reproductive health. It’s not obvious how these might connect to an ovarian condition.

This underscores why knowing your body and being aware of persistent changes is so important. If symptoms last more than two weeks, it’s worth discussing them with your healthcare provider.

Who’s Most Likely to Experience Symptoms?

While anyone with ovaries can develop borderline tumors, they’re most common in women between 20 and 40 years of age. About one-third of patients diagnosed with a borderline ovarian tumor are younger than 40 years old.

Unlike invasive ovarian cancer, which typically affects women after menopause, borderline tumors often develop during prime reproductive years, making symptom awareness especially important for younger women.

How Symptoms Lead to Diagnosis

When you report symptoms consistent with a borderline ovarian tumor, your doctor will typically begin with:

• A detailed medical history
• A physical examination, including a pelvic exam
• An ultrasound of the pelvis and abdomen
• Blood tests, which may include the CA-125 tumor marker, although it’s important to note that CA-125 levels are negative in approximately 54% of borderline tumor cases and may be less reliable in younger women. Common conditions like menstruation, fibroids, and pregnancy can increase CA-125 levels, making it less specific. While CA-125 is most specific for evaluating postmenopausal pelvic masses, even in those cases, its accuracy isn’t perfect.

If an ovarian mass is detected, additional imaging, like MRI, may be recommended to better characterize the lesion before surgery.

When to Seek Immediate Medical Attention

While many borderline ovarian tumor symptoms develop gradually, certain situations warrant immediate medical care:

• Severe, sudden abdominal pain
• Fever accompanied by pelvic pain
• Dizziness, fainting, or extreme weakness
• Heavy vaginal bleeding
• Inability to keep food down due to nausea/vomiting

These symptoms could indicate complications like tumor rupture or torsion (twisting) of the ovary, which require emergency attention.

After Diagnosis: Symptom Changes Following Treatment

The primary treatment for borderline ovarian tumors is surgery, which typically resolves symptoms. Depending on the stage of the tumor and your desire to preserve fertility, your surgeon may recommend:

• Removing only the affected ovary and fallopian tube
• Removing both ovaries and fallopian tubes
• More extensive surgery, including hysterectomy

After surgery, most symptoms should steadily improve. However, some women experience temporary symptoms from the surgery itself, including:

• Incision pain
• Shoulder pain (from residual gas if laparoscopy was performed, though gas pain is typically more noticeable in the stomach and feels distinctly different from post-operative soreness)
• Constipation (common after abdominal surgery)
• Fatigue during recovery

These post-surgical symptoms typically resolve within weeks as your body heals.

Long-term Symptom Monitoring

Even after successful treatment, ongoing awareness remains important. A small percentage of borderline tumors may recur, though recurrences are often non-invasive and treatable.

Follow-up typically includes regular pelvic exams to check for any physical changes. Your doctor will feel for abnormalities that might indicate a returning tumor.

Ultrasound examinations are crucial in monitoring, usually scheduled every 6 months for 2 years, then yearly after that. These imaging tests can detect small changes before they cause noticeable symptoms.

Paying attention to any returning symptoms is essential. If you notice familiar sensations like abdominal swelling or pelvic pressure returning, contact your doctor promptly.

For those who had fertility-sparing surgery with one ovary remaining, the risk of recurrence in the preserved ovary is about 20%. This makes symptom awareness particularly important for this group.

Read more: Borderline Ovarian Tumor Prognosis: What Research Tells Us About Survival and Recovery

Moving Forward with Awareness

Borderline ovarian tumor symptoms can be subtle and easy to dismiss, especially in their early stages. The key to early detection lies in paying attention to persistent changes in your body and seeking medical evaluation when symptoms last more than a couple of weeks.

While the non-specific nature of these symptoms means many women with borderline tumors are diagnosed when tumors are already sizable, the good news is that even at advanced stages, borderline tumors have an excellent prognosis with appropriate treatment.

Remember: you know your body best. Trust your instincts if something feels off, and don’t hesitate to advocate for thorough evaluation when symptoms persist.