Types of breast cancer in men

Knowing the type of cancer helps the doctors decide on the most appropriate treatment.

Ductal carcinoma in situ (DCIS)

This is the earliest form of breast cancer. In DCIS, cancer cells are in the ducts of the breast, but they haven’t started to spread into the surrounding breast tissue. DCIS is much less common in men than in women; only 5% of breast cancers in men are DCIS.

We have more information in our section on DCIS|.

Invasive breast cancer

If cancer cells have spread outside the lining of the ducts or lobules and into surrounding breast tissue, it’s called invasive breast cancer. There are different types of invasive breast cancer:

• Invasive ductal breast cancer - this is the most common type of breast cancer and accounts for more than 9 out of 10 breast cancers in men (over 90%). Because cells looked at under the microscope have no common pattern, doctors sometimes call it ‘breast cancer of no special type’. 
• Invasive lobular breast cancer - this develops from the cells that line the lobes of the breast and can sometimes be difficult to diagnose on a mammogram. Men rarely get lobular breast cancer because there are few, if any, lobules in men’s breasts.
• Inflammatory breast cancer - this is an uncommon type of breast cancer. It happens when cancer cells grow along and block the tiny channels (lymph vessels) in the skin of the breast.

The lymph vessels and the breast then become inflamed and swollen, which is how the condition gets its name. Inflammatory breast cancer is very rare in men, but we have a fact sheet we can send you if you would like to know more.

Other rare types of breast cancer include:

• medullary breast cancer
• mucinous breast cancer
• tubular breast cancer
• malignant phyllodes tumour.