Diarrhea is a common symptom that can impact quality of life. For individuals with prostate cancer, its appearance can raise concerns about a connection to their diagnosis. While prostate cancer itself does not typically cause diarrhea, its treatments and other factors often lead to digestive changes.
Prostate Cancer and Diarrhea: The Direct Link
Prostate cancer originates in the prostate gland, an organ situated below the bladder and in front of the rectum. Given its anatomical location, localized prostate cancer affects the urinary and reproductive systems, rather than directly impacting bowel function. Therefore, in its early stages, prostate cancer itself is not a common cause of diarrhea.
However, in rare instances where prostate cancer has advanced, it can lead to bowel issues. If the tumor grows extensively and presses on nearby structures like the bowel or lymph nodes in the pelvic area, it might produce symptoms such as diarrhea. If the cancer metastasizes or spreads to the spine, tumors could damage nerves that control bowel function, leading to digestive problems.
Treatments That Can Cause Diarrhea
Prostate cancer treatments are a frequent cause of diarrhea due to their effects on the body. These interventions, while targeting cancer cells, can also impact healthy cells in the digestive tract.
Radiation therapy, a treatment for prostate cancer, often leads to bowel problems. External beam radiation therapy (EBRT) and brachytherapy (internal radiation) can irritate the lining of the bowel, causing inflammation known as radiation proctitis. This irritation can result in loose, watery bowel movements, increased urgency, and abdominal discomfort. While severe bowel problems are uncommon during radiation, softer stools or diarrhea can occur, with symptoms resolving within a few weeks or up to 6 to 12 months post-treatment.
Chemotherapy drugs target rapidly dividing cells, including cancer cells and healthy cells in the lining of the intestines. This impact on the gut lining can impair the intestines’ ability to absorb water and nutrients, leading to diarrhea. Common chemotherapy drugs used for prostate cancer, such as docetaxel and cabazitaxel, list diarrhea as a side effect. Diarrhea from chemotherapy appears within the first few days or one to two weeks after treatment.
Hormone therapy, also known as Androgen Deprivation Therapy (ADT), aims to reduce testosterone levels, which can slow prostate cancer growth. While less frequently associated with severe diarrhea compared to radiation or chemotherapy, some hormone therapy drugs, particularly antiandrogens like flutamide, can cause gastrointestinal upset, including diarrhea. The side effects of hormone therapy are related to lowered testosterone levels and can persist as long as the treatment continues.
Surgery, a prostatectomy, involves removing all or part of the prostate gland. Direct bowel injury during prostatectomy is rare. However, bowel changes in the initial weeks after surgery can occur as the body adjusts to the altered abdominal space. Post-surgical complications or antibiotics administered during or after the procedure might temporarily contribute to diarrhea.
Other Reasons for Diarrhea in Prostate Cancer Patients
Diarrhea is a common symptom with many causes beyond prostate cancer or its direct treatments. Patients may experience diarrhea due to other medications they are taking. For instance, antibiotics can disrupt the natural balance of gut bacteria, leading to diarrhea, while certain antacids containing magnesium, metformin for diabetes, and some antidepressants can also cause this symptom.
Dietary factors play a role in digestive health. Food intolerances, such as lactose or gluten sensitivity, can result in diarrhea if specific foods are consumed. An excessive intake of certain foods or drinks, including coffee, alcohol, artificial sweeteners like sorbitol or mannitol, fatty foods, or very spicy dishes, can trigger or worsen diarrhea. Changes in diet due to illness or treatment can also affect bowel habits.
Infections, such as viral or bacterial infections, are frequent causes of diarrhea. These infections can occur independently of the cancer diagnosis or its treatment. Underlying bowel conditions like Irritable Bowel Syndrome (IBS), Crohn’s disease, or ulcerative colitis can also manifest with diarrhea and may coexist in prostate cancer patients.
The stress and anxiety associated with a cancer diagnosis and its treatment can impact gut health. The brain and gut are intricately connected through the gut-brain axis, and stress can alter gut motility, increase intestinal permeability, and affect the balance of gut bacteria, leading to symptoms like diarrhea. This physiological response to stress can accelerate bowel movements and contribute to digestive distress.
When to Seek Medical Attention and Management Strategies
Recognizing when diarrhea warrants medical attention is important for prostate cancer patients. Contact a healthcare provider immediately if experiencing six or more loose bowel movements a day for more than two days, or if there is blood in the stool or rectal area. Other warning signs include a fever of 100.5 degrees Fahrenheit (38 degrees Celsius) or higher, weight loss due to diarrhea, an inability to control bowel movements, or abdominal cramps lasting more than a day. Dizziness, particularly when standing up, can indicate dehydration and requires prompt medical review.
For milder cases of diarrhea, several home management strategies can offer relief. Staying well-hydrated is important to replace fluids and electrolytes lost, so drinking plenty of clear liquids like water or broth is advisable. When able to eat, starting with small, frequent meals of bland, low-fiber foods such as bananas, white rice, applesauce, and toast can be beneficial. Avoiding trigger foods like spicy dishes, high-fat items, excessive caffeine, and dairy products may help.
It is recommended to discuss any new or worsening symptoms with the oncology team or primary care physician. They can assess the cause of the diarrhea, adjust treatment plans if necessary, and recommend appropriate anti-diarrheal medications or other interventions. Open communication with healthcare providers ensures that diarrhea is managed effectively, preventing complications like dehydration and maintaining overall well-being during and after prostate cancer treatment.