An armpit itch typically results from a skin condition. But certain health conditions, including some types of cancer, can cause an itchy rash in your armpit and other symptoms.

Itchy armpits are likely caused by a noncancerous condition, such as inadequate hygiene or dermatitis. But in some cases, the itch can be a sign of cancer, like lymphoma or inflammatory breast cancer.

Lymphoma is a cancer of the lymphatic system. It can cause swelling of the lymph nodes, commonly in the underarms, groin, or neck.

Hodgkin’s and non-Hodgkin’s lymphoma

While there are more than 70 typesTrusted Source of lymphomas, doctors typically divide lymphomas into two categories: Hodgkin’s lymphoma (HL) and non-Hodgkin’s lymphoma (NHL).

About 30% of people with HL and 15% of people with NHL experience itchingTrusted Source. Experts sometimes refer to this as Hodgkin itch or paraneoplastic pruritus.

Hodgkin itch typically is not accompanied by an obvious skin rash. Scratching does not relieve Hodgkin itch.

T-cell and B-cell skin lymphoma

T-cell and B-cell skin lymphoma can produce a rash that accompanies the itch. This can have characteristics that include:

  • mycosis fungoides, which are small patches of dry, red skin that may resemble psoriasis, eczema, or dermatitis
  • skin hardening and thickening, as well as the formation of plaques that may itch and ulcerate
  • papules, which are raised areas of skin that may eventually grow and form nodules or tumors
  • erythroderma, which is a general reddening of the skin that can be dry, scaly, and itchy

Breast cancer is cancer that develops in the breast cells. A rare form of breast cancer called inflammatory breast cancer can cause symptoms that may include itching.

If your breast is tender, swollen, red, or itchy, your doctor might first consider infection rather than inflammatory breast cancer. The treatment for infection is antibiotics.

If antibiotics do not make the symptoms better in 7 to 10 daysTrusted Source, your doctor may perform tests for cancer, such as a mammogram or breast ultrasound.

Although itchiness, including in your armpit, can be a symptom of inflammatory breast cancer, other noticeable symptoms typically accompany it. These can include:

  • skin changes such as thickening or pitting that gives breast skin the look and feel of orange peel
  • swelling that makes one breast look larger than the other
  • one breast feeling heavier and warmer than the other
  • one breast with redness or discoloration that covers more than one-third of the breast

How often do itchy armpits suggest cancer?

A 2022 study of more than 300,000 people noted that those who experienced itching without a known cause were more likely to have a blood cancer, like lymphoma, than people who didn’t experience itching.

However, only a tiny percentage of people in the study ended up with a blood cancer diagnosis: less than 0.4% after 1 year and still less than 1% after 10 years.

Your itchy armpits are likely due to something other than cancer. Common causes include:

  • Inadequate hygiene: Bacteria will grow in places that collect dirt and sweat. To prevent itchy armpits, keep your underarms clean, especially after physical activity.
  • Dermatitis: Allergic, atopic, or contact dermatitis are all potential skin conditions that could appear in your armpits and create itchiness.
  • Chemicals: Your soap, deodorant, or laundry detergent could be triggering the itch in your underarms. Consider changing brands or using a natural alternative.
  • Prickly heat: Also known as heat rash and miliaria rubra, prickly heat is a bumpy, red rash that people who live in humid and hot environments sometimes experience.
  • Dull razor: Shaving with a dull razor or without shaving cream can result in armpit irritation, dryness, and itchiness.
  • Hyperhidrosis: A disorder of the sweat glands, hyperhidrosis involves excessive sweating that can lead to irritation and itch.
  • Bras: Some people who wear bras have an itchy allergic reaction to bras made with nickel, rubber, or latex.
  • Intertrigo: Untreated intertrigo (a rash in the skin folds) can cause a bacterial or fungal infection. Heat, high humidity, inadequate hygiene, diabetes, and obesity can all increase your risk of intertrigo.

If you experience itchy armpits together with other early cancer symptoms, you should contact a doctor. They can examine your symptoms and perform tests, if necessary, to determine the cause of your itching.

The National Cancer InstituteTrusted Source also recommends seeing a doctor if you experience itching throughout your body, especially if it interferes with regular daily activities or doesn’t go away.

Even if you suspect another cause, like an infection or skin condition, contacting a doctor can be helpful. They can suggest or prescribe treatments.

How I Cope: Liz's Breast Cancer Story
Watch as Liz shares her personal breast cancer journey.
0 seconds of 4 minutes, 10 secondsVolume 0%
Press shift question mark to access a list of keyboard shortcuts
00:00
04:10
04:10
 

If your armpits are itchy, a noncancerous condition such as inadequate hygiene, dermatitis, or an allergic reaction is likely the cause.

In most situations, if cancer is behind the itch, other symptoms will accompany it. These can include swelling, skin discoloration, warmth, and skin changes like thickening and pitting.

If you think your itchy armpits may be indicative of cancer, talk with a doctor. After a diagnosis, they can recommend treatment to address any underlying conditions that caused the itchiness.