Can Pyoderma Gangrenosum Be Linked to Leukemia or MDS?

A diagnosis of pyoderma gangrenosum (PG) can naturally cause anxiety, especially if you have read about its potential links to blood disorders like leukemia or myelodysplastic syndrome (MDS). The direct answer is that while these blood conditions are known associations with PG, the vast majority of people with PG do not have leukemia or MDS. When another condition is present, it is much more likely to be inflammatory bowel disease (IBD) or inflammatory arthritis ^[1].

However, because the link to blood disorders exists, your doctor may include basic blood tests in your initial evaluation. Understanding what they are looking for can help you feel more prepared and less anxious about the process. A normal blood test is reassuring, and an abnormal one is simply a clue for further evaluation, not a cancer diagnosis.

The Connection Between PG and Blood Disorders

Research shows that more than half of all people with PG have some form of underlying condition affecting the body ^[1]. While IBD and arthritis are the most common, hematological (blood) disorders are also recognized, though uncommon, associations ^[1].

When blood disorders do occur with PG, myelodysplastic syndrome (MDS) — a condition where blood cells do not form properly in the bone marrow — is frequently reported in medical literature, along with acute myeloid leukemia (AML) ^[2]. Doctors also sometimes see associations with monoclonal gammopathy of undetermined significance (MGUS), which is an abnormal protein condition in the blood, not a cancer or leukemia ^[2]. Keep in mind that these associations mean the conditions can coexist; it does not mean that PG causes blood cancer, or that you are likely to have it.

Does the Appearance of PG Matter?

The physical appearance of your PG can sometimes provide clues to your medical team.

• Classic PG usually starts as a painful nodule that breaks down into a deep ulcer with a purple, overhanging border.
• Bullous PG features fluid-filled blisters, while atypical PG may look more like superficial erosions.

In clinical reports, the bullous and atypical patterns have been noted to occur alongside blood disorders like AML or abnormal protein conditions ^[3][4][5]. However, there is no set rule that the appearance of your ulcer predicts cancer. These are just patterns that might prompt your doctor to look a bit closer at your blood work.

Screening: The Complete Blood Count (CBC)

A Complete Blood Count (CBC) with a differential is commonly included in the initial evaluation of PG. This is a standard blood test that measures the levels of your red blood cells, white blood cells, and platelets.

If your CBC comes back showing high white blood cell counts, do not panic. PG is a highly inflammatory condition, and studies show that 50% to 73% of patients with PG have elevated white blood cells (specifically leukocytosis and neutrophilia) due to the inflammation ^[6]. High white blood cells can also be caused by bacterial infections in the ulcer or by medications like corticosteroids. An elevated white count during an active PG flare does not automatically mean you have leukemia.

Note: If you experience a new fever, chills, rapidly worsening pain or redness, or pus draining from your wound, contact your doctor promptly, as these can be signs of an infection rather than just PG inflammation.

When Is a Referral to a Hematologist Needed?

Your dermatologist or primary care doctor will monitor your blood work and symptoms. They may refer you to a hematologist (a doctor who specializes in blood disorders) if they see specific patterns that need an expert’s review. These referrals are for evaluation, not because they have diagnosed a cancer. Reasons for a referral might include:

• Persistent CBC abnormalities: Unexplained anemia (low red blood cells), persistently low platelets, or white blood cell counts that remain highly abnormal even as your skin improves.
• Abnormal cells: If a peripheral blood smear (a test looking at your blood under a microscope) reveals abnormal or immature blood cells, sometimes called “blasts.”
• Systemic symptoms: Unexplained weight loss, drenching night sweats, unusual bruising or bleeding, or recurrent infections. (If you experience severe bleeding or feel acutely unwell, seek urgent medical care.)
• Treatment-resistant PG: If your PG does not respond to standard treatments, doctors will first reassess the diagnosis, check for infection, or adjust medications. If those are ruled out, it can sometimes prompt a deeper look for underlying conditions ^[7].

Remember, while the association between PG and blood disorders is real, it is uncommon relative to other conditions. Routine monitoring is a standard precaution, not a reason to assume the worst. If anxiety about these associations is disrupting your sleep or daily life, let your care team know so they can help you interpret your specific test results.