Young woman sitting on chair and researching the signs of colon cancer in women

7 Signs of Colon Cancer in Women

Updated March 12, 2024. Medically reviewed on June 15, 2020 by Neka Miller, PhD. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.


Although colon cancer (also referred to as colorectal cancer) can develop at any age in adults, it typically affects women and men who are over the age of 50. Among women, the lifetime risk of developing colorectal cancer is about 1 in 25, compared to 1 in 23 in men. [1]


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There are many risk factors for developing colon cancer in women, which can include obesity, low physical activity, and smoking, as well as high salt and red meat consumption. [1] That said, it’s important to note that women are historically underrepresented in colon cancer research, and these risk factors are very often extrapolated from male-based studies. [2]

Nonetheless, research suggests that colon cancer symptoms are the same, regardless of sex or gender. Read on to discover the signs of colon cancer in women.

1. Unexplained Rectal Bleeding

It’s common to experience bleeding from the rectum or lower colon in the case of colon cancer. In most cases, the blood, which is found in the stool, is bright red. In other cases, the stool might look darker than normal. [3]

It’s always important to pay attention to rectal bleeding and alert your healthcare provider that you’re experiencing this symptom. While it can point to colon cancer, rectal bleeding may also be the result of [4]:

  • Hemorrhoids
  • Crohn’s disease
  • Ulcerative colitis
  • Anal fissure
  • Inflammatory bowel disease
  • Diverticulitis

2. Iron Deficiency Anemia

Iron deficiency anemia can develop in women whose bodies are not getting enough iron, generally due to such factors as [5]:

  • Blood loss – Blood loss can occur from bleeding within the gastrointestinal and/or urinary tract, heavy menstrual cycles, bleeding during childbirth, injury, and surgery.
  • Iron malabsorption – In some cases, certain conditions can disrupt intestinal function, preventing the body from adequately absorbing iron. Other times, endurance sports and genetic conditions play a role.
  • Kidney disease – Women with kidney disease are often deficient in a substance that makes red blood cells.
  • Chronic inflammation – Congestive heart failure or obesity can make it more difficult for the body to absorb and use iron.
  • Research identifies iron deficiency anemia as the most common symptom of colon cancer that occurs outside of the intestines. The cancer can make the body use up iron faster than usual, reduce the absorption of dietary iron, and cause bleeding over time. [6]

    In general, iron deficiency anemia doesn’t cause noticeable symptoms. In some cases, however, symptoms may include pallor (more pale-looking skin), fatigue, and shortness of breath. [5]

    3. Bowel Habit Changes

    It’s very common for patients with colon cancer to experience changes in their bowel movements. These include [6]:

    • Narrow, ribbon-like stools
    • More frequent bowel movements
    • Loose stool
    • Constipation
    • Bowel obstruction in your small or large intestine [9]

    These symptoms can last for several days, but they aren't always indicative of cancer. Changes in bowel movements may be indicative of advanced bowel cancer or could be a symptom of irritable bowel syndrome (IBS). It's important to get tested to determine whether the changes are being caused by colon cancer vs. IBS, for example, which can have similar bowel movement symptoms.


    Related: What can cause a change in bowel habits?


    4. Tenesmus

    Another potential symptom of colon cancer in women is tenesmus. Tenesmus is a recurring, often painful urge to urinate or defecate—but no (or very little) waste passes. [8]

    Rectal tenesmus is commonly associated with tumors located in the rectosigmoid region or the rectum itself. However, it can also occur in other conditions unrelated to cancer, such as [9]:

    • Dysentery: Inflammation of the intestine often caused by infection
    • Hemorrhoids: Swollen veins in the rectum or anus
    • Ulcerative colitis: Inflammatory bowel disease affecting the colon and rectum
    • Parasitic infections: Caused by parasites or certain types of worm infestations like pinworms or tapeworms

    5. Abdominal Pain

    Cramping and bloating are common symptoms in women and people assigned female at birth (AFAB) who menstruate. In fact, in patients with endometriosis, it may be difficult to differentiate menstrual pain from pain associated with a cancerous tumor. Both can arise in the lower abdomen.

    That said, abdominal pain, bloating, and nausea are potential symptoms of colon cancer in women. These possible colon cancer symptoms can occur after you eat and can be so uncomfortable that they cause a reduction in food intake (and eventual weight loss). [3]

    If you’re unsure of the source of your abdominal pain, schedule an evaluation with your healthcare provider.

    Everlywell FIT Colon Cancer Screening Test CTA graphic

    6. Weakness and Fatigue

    In the early stages of colon cancer, tumors can bleed into the digestive tract, leading to blood loss and inadequate levels of iron within the body. Accordingly, patients may experience feelings of weakness and fatigue. [10]

    Those occasional feelings of weakness and fatigue happen to us all. But if you’re often exhausted, even when you’ve gotten enough shut-eye, it’s worth bringing this up to your healthcare provider as it may be a sign of a health condition—including colon cancer.

    7. Unexplained Weight Loss

    Sudden and unexplained weight loss is another symptom of colon cancer in women. [3] This may be due to cancer cells using up more of the body’s energy, the body’s response to the cancer, or a decrease in food intake due to pain or discomfort. So if you notice a sudden dip in the scale—and you’re not intentionally trying to lose weight—discuss this symptom with your healthcare provider. It may be an indicator of colon cancer or some other health condition that you as a patient should be treated for.

    Later Signs of Colon Cancer in Women

    Colon cancer is categorized into three stages [11]:

    • Localized – Cancer is confined to the inner lining of the colon or rectum and has not spread beyond the wall of the colon.
    • Regional – Cancer has spread beyond the colon or rectum to nearby lymph nodes or tissues but has not reached distant organs.
    • Distant – Cancer has metastasized (spread) to distant organs or tissues, such as the liver, lungs, or other distant sites in the body, beyond the colon and nearby lymph nodes.
    • When cancerous growths metastasize—spreading to other areas of the body—patients may experience various symptoms. Here’s a list of some possible symptoms based on the part of the body that the cancer has spread to.

    Bones

    While colon cancer does not commonly metastasize to the bones, it can occur in 3 to 7% of patients, particularly those who have colon cancer coupled with rectal cancer (colorectal cancer). [12]

    When bones are affected, signs may include [13]:

    • Fractures
    • Pain
    • Spinal cord compression, which can cause back pain, numbness, weakness, and incontinence
    • High blood calcium levels, which may cause constipation, weakness, muscle aches, and frequent urination

    Lungs

    A 2022 review on pulmonary metastases from colorectal cancer identified one study that found that isolated pulmonary metastasis (cancer that only spreads to the lungs and nowhere else) occurred in 12% of patients with rectal cancer and 6% of patients with colon cancer. [14]

    Symptoms of lung metastases include [15]:

    • Shortness of breath
    • Coughing, sometimes with the presence of blood
    • Chest pain
    • Fluid around the lungs
    • Decreased appetite
    • Weight loss

    Liver

    It’s common for colon cancer to spread to the liver due to its close proximity to the colon. About 25% of patients with colon cancer will also develop colorectal liver metastases. [16]

    Signs of liver metastases include [17]:

    • Loss of appetite
    • Fatigue and weakness
    • Fever
    • Itchy skin
    • Jaundice
    • Bloating
    • Swollen legs
    • Pain in the upper right abdomen

    Lymph nodes

    Colon cancer spreads to the lymph nodes in less than 2% of colon cancer cases. When it does, it signifies late-stage colon cancer. [18]

    Bloating, a swollen belly, and a loss of appetite are among the possible colorectal cancer symptoms one may experience when colon cancer has spread to the lymph nodes. [19]

    Brain

    It’s uncommon for colon cancer to spread to the brain, but it can occur. Unfortunately, this indicates a poor prognosis. [20] When the brain is affected, patients may experience [21]:

    • Headaches
    • Seizures
    • Weakness of the arms and/or legs
    • Memory loss
    • Problems with speech
    • Personality or behavior changes
    • Vision problems
    • Numbness
    • Hearing loss

    Screen for Colon Cancer Comfortably and Discreetly with Everlywell

    Colorectal cancer typically develops from a precancerous polyp in the colon—an abnormal growth also known as a “ colon polyp”—which can often be detected with colorectal cancer screening tests. Once a colon polyp is identified, it can be removed to prevent colorectal cancer.

    When should you get a colorectal cancer screening? This largely depends on one’s age. The U.S. Preventive Services Task Force (USPSTF) recommends routine bowel cancer screening every year for women and men in the 50-75 age range (for those at average risk). This is because people in this age range are at a particularly increased risk of colon cancer compared to younger populations.

    Screening tests can include a colonoscopy, sigmoidoscopy, or fecal occult blood test (FOBT) such as a fecal immunochemical test (FIT). Fortunately, bowel cancer screening can be done from the comfort and privacy of home with Everlywell’s at-home Colon Cancer Test. Simple sample collection and results you can easily share with your healthcare provider make this a convenient option for routine screenings.


    Related: Who is at risk for colon cancer?



    Sources

    1. Lewandowska A, et al. Risk Factors for the Diagnosis of Colorectal Cancer. Cancer Control. Medical Citation URL. Accessed February 21, 2024.
    2. Baraibar I, et al. Sex and gender perspectives in colorectal cancer. ESMO Open. Medical Citation URL. Accessed February 21, 2024.
    3. Colon Cancer Symptoms. Johns Hopkins Medicine. Medical Citation URL. Accessed February 21, 2024.
    4. Rectal Bleeding. Cleveland Clinic. Medical Citation URL. Accessed February 21, 2024.
    5. Iron-Deficiency Anemia. NIH. Medical Citation URL. Accessed February 21, 2024.
    6. Chardalias L, et al. Iron Deficiency Anemia in Colorectal Cancer Patients: Is Preoperative Intravenous Iron Infusion Indicated? A Narrative Review of the Literature. Cancer Diagn Progn. Medical Citation URL. Accessed February 21, 2024.
    7. Colorectal Cancer Signs and Symptoms. American Cancer Society. Medical Citation URL. Accessed February 21, 2024.
    8. Tenesmus. Cleveland Clinic. Medical Citation URL. Accessed February 21, 2024.
    9. Stoicescu M. The Semiology of the Bowel. Medical Semiology Guide of the Digestive System. Medical Citation URL. Accessed February 21, 2024.
    10. Anemia and Colon Cancer. The Endoscopy Center. Medical Citation URL. Accessed February 21, 2024.
    11. Survival Rates for Colorectal Cancer. American Cancer Society. Medical Citation URL. Accessed February 21, 2024.
    12. Christensen T, et al. Systematic review: Incidence, risk factors, survival and treatment of bone metastases from colorectal cancer. J Bone Oncol. Medical Citation URL. Accessed February 21, 2024.
    13. Bone Metastases. American Cancer Society. Medical Citation URL. Accessed February 21, 2024.
    14. Chiappetta M, et al. Management of single pulmonary metastases from colorectal cancer: State of the art. World J Gastrointest Oncol. Medical Citation URL. Accessed February 21, 2024.
    15. Lung Metastases. American Cancer Society. Medical Citation URL. Accessed February 21, 2024.
    16. Martin J, et al. Colorectal liver metastases: Current management and future perspectives. World J Clin Oncol. Medical Citation URL. Accessed February 21, 2024.
    17. Liver Metastases. American Cancer Society. Medical Citation URL. Accessed February 21, 2024.
    18. Kim H, Choi G. Clinical Implications of Lymph Node Metastasis in Colorectal Cancer: Current Status and Future Perspectives. Ann Coloproctol. Medical Citation URL. Accessed February 21, 2024.
    19. Lymph Nodes and Cancer. American Cancer Society. Medical Citation URL. Accessed February 21, 2024.
    20. Goksu S, et al. The pattern of brain metastasis in colorectal cancer: Efficacy of metastasectomy, chemotherapy. Journal of Clinical Oncology. Medical Citation URL. Accessed February 21, 2024.
    21. Bettegowda, C. Metastatic Brain Tumors. Johns Hopkins Medicine. Medical Citation URL. Accessed February 21, 2024.

    Neka Miller, PhD holds a PhD in Molecular Pharmacology and is an experienced technical writer covering topics including pharmacology, cancer initiation, neuroscience, and traumatic brain injury. Miller has also created manuals and custom reports featuring data visualizations, protocols, method sections, and manuscripts, as well as authoring published works in scientific journals. Miller has been performing research, writing, and publishing works for over 15 years, and currently serves as the Director of Institutional Effectiveness as well as an Adjunct Professor in the Doctor of Healthcare & Education Leadership (Ed.D.) program at Clarkson College.
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