A skin rash can develop for many reasons, most of which are unrelated to cancer. Even so, a rash could be a sign of an underlying medical condition that requires treatment, such as internal cancer or blood/lymph node cancers (leukemia and lymphoma). Therefore, any unusual skin changes that are not responding to usual treatments should be promptly discussed with a medical provider.
Leukemia
- Leukemia – Leukemia is a blood cancer that develops in the bone marrow, caused by the rapid production of abnormal white blood cells. These white cells impair the body’s ability to produce red blood cells and platelets. A low platelet count can lead to easy bruising and bleeding under the skin, which forms tiny red spots on the skin’s surface (petechiae) that resembles a rash. While petechia are not always a sign of leukemia, a patient with persistent petechia should be evaluated by their primary care doctor.
- Leukemia Cutis – Leukemia cutis refers to the infiltration of the skin with malignant abnormal leukemia cells. Leukemia cutis is rare, affecting about 3% of people diagnosed with leukemia. The skin manifestations include firm lumps and bumps, which may be skin-colored, red, brown or purple.
Lymphomas
- Cutaneous B-cell Lymphoma – Cutaneous B-cell lymphoma (CBCL) is a type of non-Hodgkin’s lymphoma that attacks the skin. It is a rare type of cancer, affecting only about 4 of every 1 million people. CBCL usually presents with a solitary lump, bump, or nodule on your skin. It may look red, purple or brown. Lesions may be slightly raised and solid but smooth. The lesions are usually slow glowing and rarely spread or affect other parts of your body. Treatment usually involves surgical removal.
- Mycosis fungoides – A type of cutaneous T cell lymphoma, mycosis fungoides occurs when certain white blood cells (lymphocytes) undergo cancerous changes that cause them to attack the skin. The early signs include itchy, rash-like skin patches (may look like eczema or psoriasis at first), which may form sores and tumors as the cancer progresses.
- Sézary syndrome – A leukemic variant of mycosis fungoides, Sézary syndrome causes an extensive, itchy red rash over at least 80% of the body.
Itchy skin with no rash – is it cancer?
It’s possible……While itchy skin is commonly associated with rashes, not all rashes are itchy, and not all itchiness is accompanied by a rash. Lymphomas are one type of internal cancer that could be associated with itching without a rash.
Other types of cancers that could present with itching include:
- Bile duct cancer
- Gallbladder cancer
- Liver cancer
- Kidney cancer
- Lung cancer
Take away points:
There are many different conditions that can lead to a rash, from allergic reactions to common skin conditions. Examining your skin regularly and educating yourself about signs of both internal and external cancer will equip you to identify any unusual changes and act quickly. Talk to your health care provider if you are concerned about a rash on your body.
