What Cancer Can Cause Itchy Skin?

Itchy skin, or pruritus, can be a symptom of some cancers, including blood-related, skin, liver, gallbladder, and bile-duct cancer cancers. However, other causes of itching are more common.

Itching may occur due to direct irritation of the skin, such as with skin cancer or a separate cancer that has spread or metastasized to the skin.

Itching as a Cancer Symptom

If you are feeling itchy on occasion, it is unlikely due to cancer. It's uncertain exactly how often itching occurs as a symptom or first symptom of cancer.

In up to 50% of individuals, persistent or generalized itching may be due to an underlying disease, such as cancer.

However, other conditions, such as liver disease, kidney disease, or blood disorders, can also cause persistent itching.

A 2019 study explored how often those with itching had cancer compared to individuals without itching. The researchers found that individuals with itching were nearly six times more likely to have an associated malignancy (cancer) than those without itching.

The cancers that were most commonly associated with itching included:

• Blood-related cancers (leukemias and lymphomas)
• Skin cancer
• Liver cancer
• Gallbladder cancer
• Bile duct cancer

The researchers also divided patients by race. Black patients with itching were more likely to experience the following cancers:

• Skin cancer
• Soft tissue cancers (such as sarcomas that can start in muscles and fat)
• Blood-related cancers

White patients were more likely to have:

• Liver cancer
• Lung cancer
• Digestive tract cancers
• Cancers of the female reproductive tract, such as ovarian cancer.
  

Cancers That Cause Itching

Several cancers can cause itchy skin. Blood cancers, skin cancers, and cancers that can cause cholestasis (obstruct the flow of bile) are the most likely to cause itching. However, itchy skin can also be a sign of cancers that affect the genitals, specific forms of breast cancer, and other cancer types.

Blood Cancers

Any blood-related cancer can cause itching, including:

• Hodgkin lymphoma
• Noncutaneous non-Hodgkin lymphoma
• Primary cutaneous lymphoma
• Lymphocytic leukemia
• Myeloid leukemia
• Multiple myeloma

The two blood-related cancers most likely to cause itching are primary cutaneous lymphoma and myeloid leukemia.

Cutaneous T-cell lymphoma is a primary cutaneous lymphoma (meaning it starts in the skin). It is a rare cancer that begins in the T cells (a white blood cell). It can lead to rash-like redness, scaly patches or plaques, and tumors.

The most common type of cutaneous T-cell lymphoma is called mycosis fungoides. A less common form, Sezary syndrome, can lead to a condition called erythroderma—a severe skin condition that can cause peeling, red skin across the entire body.

Other examples that can lead to itching include myelodysplastic syndromes that cause low numbers of blood cells and myeloproliferative disorders that cause an overproduction of blood cells.

Myelodysplastic syndromes and chronic myeloproliferative disorders are considered types of cancer. Some myelodysplastic syndromes progress to leukemia.

Skin Cancers

Skin cancer often causes itching. Itching is more common with basal cell carcinoma and squamous cell carcinoma. Itching is less common with melanoma but may still be a symptom.

Liver, Bile Duct, Pancreatic, and Gallbladder Cancer

Several conditions can affect the bile ducts, leading to obstruction and the consequent buildup of bile salts in the skin. This can cause diffuse itching. When bile flow is impaired or altered, it is known as cholestasis.

Other symptoms may include yellowing of the skin, dark urine, abdominal pain, and fluid collection in the abdomen (ascites).

Several cancers can contribute to cholestasis, such as pancreatic cancer, cancer of the bile ducts, and cancer in the liver. However, several non-cancerous conditions can also cause cholestasis, such as hepatitis, pancreatitis, and bile duct stones.

Vulvar Cancer and Anal Cancer

Genital itching is more likely due to other causes than cancer. However, itching may be a symptom of vulvar cancer or anal cancer.

Breast Cancer

Itching as a symptom of breast cancer isn't common, but it may occur, especially in inflammatory breast cancer or Paget disease of the breast.

Inflammatory breast cancer: This is a rare, aggressive form of breast cancer that can cause redness in one breast, an inverted nipple, and pitting of the skin (resembling an orange peel) on one breast, among other symptoms. Itching may also be present.

Paget disease of the breast: This cancer primarily affects the nipple and areola of one breast. Symptoms may resemble eczema at first, and the nipple may appear scaly or red. Itching and burning are additional symptoms. This cancer is often found alongside other forms of breast cancer.

Neuroendocrine Tumors (NETs)

Neuroendocrine tumors are slow-growing tumors that affect the neuroendocrine cells—cells found throughout the body that send messages via hormones. They are rare in children, but when they occur, they are typically found in the appendix or lungs.

In adults, they are most commonly found in the GI tract and are called GI NETs. However, in adults, NETs are more likely to spread.

NETs can cause a condition called carcinoid syndrome. Skin flushing and itching can occur with carcinoid syndrome.

Metastatic Cancer

Cancer that originated somewhere else in the body and spread to the skin, known as metastatic cancer to the skin or skin metastases, may cause itching.

Common sources of skin metastases include:

• Breast cancer
• Lung cancer
• Colorectal cancer

Liver metastases, or cancer that started someplace else and spread to the liver, may also lead to itching, similar to the itching associated with primary liver cancers that begin in the liver.

The most common cancers that spread to the liver include:

• Colorectal cancer
• Breast cancer
• Esophageal cancer
• Gastric or stomach cancer
• Pancreatic cancer
• Lung cancer
• Kidney cancer
• Melanoma

How Cancer Causes Itching

There are several ways that cancer can lead to itching. The body contains several nerve endings that cause itching, similar to pain receptors that cause pain.

In general, anything that irritates these nerve endings can cause itching.

Inflammation: Blood cancers (e.g., leukemias) are more likely to cause skin eruptions, such as bumps, rashes, or other lesions. These inflammatory skin conditions can feel itchy.

Bile salt buildup: Bile is a digestive liquid produced by the liver and mostly made of bile salts. Blocked bile ducts can lead to the buildup of bilirubin (a waste product of broken-down red blood cells) in the bloodstream.

Cancers that can cause this include cancers in the bile duct, pancreatic cancer, and cancer in the liver.

Mast cells and histamine release: Some cancers, such as mycosis fungoides (a type of cutaneous T-cell lymphoma), can cause histamine release, resulting in itching.

Paraneoplastic syndromes: These are symptoms that occur away from the tumor or cancer's location on the body. It is thought that chemicals secreted by tumors or an antibody reaction against the tumors cause the symptoms.

Paraneoplastic syndromes encompass a wide variety of symptoms and conditions. When paraneoplastic syndromes affect the skin, itching is the most common symptom.

Cancer Treatments and Itching

The majority of cancer treatments have itching as a potential side effect. Additionally, many medications used to help alleviate cancer symptoms can also cause itching. Examples of treatments that can cause itching include:

• Chemotherapy, or the use of medications to kill cancer cells, particularly if there is a sensitivity to the drug. Many medications can also cause allergic reactions or inflammation of the liver, which can lead to itching.
• Immunotherapy drugs or treatments that stimulate your immune system to fight the cancer can cause itching—especially interferon and interleukin-2.
• Radiation therapy, or using high-powered energy waves to destroy cancer cells, commonly causes itching, especially later in treatment when the skin begins to heal.
• Supportive care medications, such as opioids used for pain relief or anti-nausea medications, can cause itching.
  

Management

Managing itching with cancer is essential in improving your quality of life, especially when itching is severe, such as with liver metastases or T-cell lymphomas.

Oftentimes, treatment of the underlying cancer reduces itching. However, this isn't always possible, such as with advanced cancers. It can take some time to resolve the itching.

Strategies for managing itchy skin, including during cancer treatment, include:

• Over-the-counter (OTC) creams and lotions
• Cornstarch or talc applied to the skin
• Prescription lotions and creams (e.g., topical steroids)
• Lukewarm baths
• Humidifier use if the air is dry
• Loose clothes
• Prescription medications (e.g., antihistamines, sedatives, and anti-depressants)
• Cool washcloth or ice
• Acupuncture

Be sure to talk to your healthcare provider before beginning any OTC remedies. Managing the itchiness depends on the cause, and your healthcare provider can help ensure effective treatments.

Non-Cancerous Causes of Itching

Several other health conditions can cause itchy skin. Individuals may experience itching due to dry skin or other conditions such as eczema. Sometimes, mental health conditions such as stress or anxiety can lead to itchy skin.

Additionally, conditions such as diabetes, thyroid disorders, and parasitic infections can also cause itchy skin.

If you experience persistent itching and are concerned that it isn't due to a benign cause, such as dry skin, contact your healthcare provider for advice. Your healthcare provider can order lab and imaging studies to determine the cause of your itching and develop an appropriate treatment plan.

Summary

Itching is usually due to something other than cancer. However, it can sometimes be a symptom of cancer or a side effect of cancer treatment.

Itching can occur for many different reasons in those with cancer. It can be due to direct skin involvement and inflammation, a buildup of bile acids under the skin, or chemicals released by tumors or in response to them.

If you have itching that is not otherwise explained, it's vital to make an appointment to see a healthcare provider to determine the underlying cause.