
Endometriosis vs. Cancer: How to Tell The Symptoms Apart
How to tell overlapping symptoms apart—and choose the right specialist when it matters

How to Tell the Difference
Ovarian cancer and endometriosis are two conditions that can affect a woman’s reproductive system. Understanding how they may be related and how they differ is important. Ovarian cancer is relatively uncommon, with approximately 20,000 new cases found annually in the United States and a lifetime risk of 1 in 78. At the same time, millions of women live with endometriosis, affecting up to 1 in 10. Because some symptoms overlap, recognizing the differences is essential for accurate diagnosis and proper treatment. This article explains how to tell the difference between ovarian cancer and endometriosis.
What Is Endometriosis?
Endometriosis occurs when tissue similar to the lining inside the uterus grows outside the uterus, including on the ovaries, fallopian tubes, and other organs in the pelvis and beyond. It can cause pain, infertility, and a range of other problems. Diagnosis can be suspected based on symptoms, blood tests, and various scans, but surgery is the only way to determine accurately whether endometriosis is present.
Symptoms of endometriosis can include painful periods, pain during sex, chronic pelvic pain, bloating and pain after eating, fatigue, and infertility.
What Is Ovarian Cancer?
Ovarian cancer is a type of cancer that begins in the ovaries and Fallopian tubes. It is often called the “silent killer” because it is difficult to detect in its early, more curable stages. As with endometriosis, a diagnosis can be suspected using scans and blood tests, but confirmation requires a biopsy, which is usually performed during surgery.
Symptoms of ovarian cancer can include bloating; pelvic pain or pressure; abdominal pain that is initially vague; difficulty eating or feeling full quickly; and urinary symptoms such as urgency or frequency.
The symptoms of these conditions are similar, but there are subtle distinctions and some clear differences in findings and presentation. When it comes to pain, both can cause pelvic and abdominal discomfort, but endometriosis-related pain often follows a cyclical pattern around the menstrual cycle, whereas pain from ovarian cancer tends to be more constant and dull, though endometriosis pain can be variable. With bloating, endometriosis may cause symptoms that come and go, often related to intestinal gas from inflammation and associated conditions such as small intestinal bacterial overgrowth (SIBO), while ovarian cancer can cause bloating due to gas and the accumulation of a fluid called ascites; this type of bloating typically worsens and does not fluctuate. Considering age, endometriosis is typically diagnosed during the reproductive years, whereas the most common type of ovarian cancer is usually found in women over 50, although endometriosis can persist into menopause and symptoms can even begin after menopause. Regarding family history, a family history of ovarian cancer increases risk and there are genetic links that can be tested for; endometriosis does not have a clear genetic link but does run in families. In terms of how symptoms unfold, endometriosis typically develops gradually over years, while ovarian cancer symptoms may appear more suddenly over weeks to months, with bloating that can be more pronounced and unremitting.
In general, ovarian cancer presents an immediate threat to life, while endometriosis presents a lifelong threat to quality of life, potentially spanning decades. The two can overlap because the risk of developing ovarian cancer in women with endometriosis is elevated by 1.5- to 3-fold. Although that increase is worrisome, it still represents a tiny percentage; however, even a fraction of one percent of millions of women translates to thousands or tens of thousands who may be affected. Expert opinion from a specialist and possibly genetic testing can help determine your risk. Research is underway to identify gene-driven biomarkers that could enable more accurate diagnosis.
It is important to remember that both endometriosis and ovarian cancer can share symptoms, and some women may have both conditions at the same time. If you are experiencing any of the symptoms described, speak with your healthcare provider. Many other conditions can cause similar symptoms, but if they persist and do not resolve, it is better to be cautious. For example, most people can have a bout of stomach flu with bloating, nausea, and painful diarrhea that typically passes within a few days to a week; symptoms lasting longer than that should be evaluated.
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Schedule Your VisitNavigating Specialist Care: Choosing the Right Expert for Endometriosis or Ovarian Cancer Concerns
Endometriosis and ovarian cancer are distinct conditions that affect the female reproductive system. While they share similarities such as pelvic pain, their differences can guide appropriate evaluation and treatment. Understanding these distinctions helps you and your doctor pursue the right diagnosis and care plan.
Getting an expert opinion from a specialist can be critical to getting on the right path for diagnosis and treatment. In most cases, a general gynecologist can point you in the right direction. If concerns are not addressed and endometriosis seems most likely, an endometriosis specialist may be the best next step. If both endometriosis and ovarian cancer are concerns due to your symptoms, age, or family history, consulting a gynecologic oncologist may be more appropriate or serve as an additional opinion. There are a few gynecologic oncologists who truly specialize in both endometriosis and ovarian cancer.
References
Bulun SE, Wan Y, Matei D. Epithelial Mutations in Endometriosis: Link to Ovarian Cancer. Endocrinology. 2019 Mar 1;160(3):626-638. doi: 10.1210/en.2018-00794. PMID: 30657901; PMCID: PMC6382454.
Quick Answers
How rare is endosalpingiosis?
Endosalpingiosis is generally considered uncommon, but “how rare” it is depends heavily on who’s being studied and how it’s found. Many cases are discovered incidentally on pathology—meaning tissue is identified under the microscope after surgery done for other reasons—so it’s likely underrecognized in the general population. In other settings (like surgical cohorts), it may appear more often simply because more tissue is being sampled and examined carefully.
What matters most for patients is that endosalpingiosis can be confused with endometriosis on imaging or even at surgery, yet it doesn’t always behave the same way clinically. If you’ve been told you have endosalpingiosis and you also have pelvic pain, bowel/bladder symptoms, or fertility concerns, our team can help interpret what that finding means in the context of your symptoms and operative/pathology reports. You’re welcome to explore our educational content on related endometriosis and uterine conditions, and reach out to schedule a consultation if you want a personalized plan.
Can endometriosis cause a painful bump near the anus?
Yes. Endometriosis can contribute to pain and pressure around the rectum and anal area, especially when disease involves the rectum/rectosigmoid region or nearby tissues. Many patients describe deep pain with bowel movements, rectal pressure, or symptoms that flare around their cycle, and those patterns can fit bowel or deep infiltrating endometriosis.
That said, a sensitive bump on the anus itself is more often something else (like a hemorrhoid, fissure, skin infection/abscess, or another localized anal/skin condition). In some cases, pelvic disease can coexist with these issues, which is why we don’t assume every finding is endometriosis—or dismiss it as “nothing.”
If you’re noticing a new, persistent, or worsening bump—especially if it’s very tender, draining, bleeding, or associated with fever—we want to evaluate the full picture. Our team can sort out whether your symptoms point toward bowel endometriosis, a separate anorectal condition, or both, and plan next steps such as a focused exam and, when appropriate, expertly interpreted imaging to map possible deep disease.
When is menstrual bleeding considered too heavy?
Menstrual flow is generally “too heavy” when it consistently disrupts your life or overwhelms your usual period products—think flooding or soaking through pads/tampons quickly, passing frequent or large clots, needing to double up, or bleeding long enough that you can’t plan around it. Another major clue is fatigue, dizziness, or shortness of breath that can come with iron deficiency from ongoing blood loss. If you’re timing your day around bathrooms, waking at night to change products, or avoiding work, exercise, travel, or sex because of bleeding, that’s not something we consider “normal.”
Heavy bleeding is a symptom, not a diagnosis, and common underlying drivers include adenomyosis, fibroids, hormonal imbalance, and sometimes endometriosis—especially when heavy bleeding shows up with severe cramps or deep pelvic pain. Because imaging and symptoms don’t always match (a scan can look “mild” while symptoms are intense), we take a symptom-led approach and look at the full pattern, including pain, pressure, clots, cycle timing, and any signs of anemia. If your bleeding feels like it’s escalating or you’ve been told to “just live with it,” our team can help you sort out likely causes and build a plan that targets the source—not just the bleeding.
How does estrogen affect the endometrium?
Estrogen is one of the main hormones that drives endometrial growth. In the first half of the menstrual cycle, rising estrogen signals the endometrium to thicken and rebuild after a period, preparing the uterus for a possible pregnancy. It also influences the local immune and inflammatory environment in the uterus, which is part of why hormonal shifts can change bleeding patterns and pain.
When estrogen’s growth signals are strong—and progesterone’s “calming” effect is weaker than expected (often described as progesterone resistance)—the endometrium can behave in a more persistently inflamed, reactive way. This hormone–inflammation pattern is especially relevant in estrogen-dependent conditions like adenomyosis and endometriosis, where tissue similar to the endometrium can contribute to ongoing symptoms. If you’re trying to make sense of heavy bleeding, severe cramping, or cycle-linked pelvic pain, our team can help you connect the hormonal biology to what you’re feeling and review next steps for diagnosis and treatment.
What does a frozen uterus mean with endometriosis?
A “frozen uterus” isn’t a separate diagnosis—it’s a descriptive term surgeons use when the uterus is essentially stuck in place because endometriosis-related inflammation has caused dense scarring (adhesions). Instead of the uterus moving freely, it may be tethered to nearby structures like the bowel, bladder, ovaries, or pelvic sidewall, sometimes pulling the uterus into an abnormal position and making pelvic anatomy hard to distinguish.
This finding often suggests more advanced disease, such as deep infiltrating endometriosis and/or significant adhesions from prior inflammation or surgery, and it can help explain symptoms like deep pelvic pain, painful sex, bowel or bladder symptoms, or pain that doesn’t match what a routine exam shows. In these cases, surgery is less about “burning spots” and more about carefully restoring normal anatomy—freeing organs, protecting ureters and bowel, and removing endometriosis at its roots. If you’ve been told your uterus is “frozen,” our team can help you understand what that implies for imaging, surgical planning, and which adjacent organs may need to be evaluated as part of a complete excision strategy.

