What is mucinous carcinoma?

Mucinous carcinoma is an invasive type of cancer that begins in an internal organ that produces mucin, the primary ingredient of mucus. The abnormal cells inside this type of tumor are floating in the mucin, and the mucin becomes a part of the tumor.

This rare type of cancer can occur in any part of the body that produces mucin. It’s more commonly found in the breast, usually along with other types of cancer cells. Approximately 5 percent of all invasive forms of breast cancer have mucinous carcinoma present.

Mucinous carcinoma is either pure or mixed. “Pure” means that these are the only cancer cells present. “Mixed” means the mucinous carcinoma cells are mixed with other cancer types.

Mucinous carcinoma may also be called colloid carcinoma. It’s a subtype of invasive ductal carcinoma that is a more common form of breast cancer. When associated with breast cancer, it usually begins in the milk duct.

Survival rate and recurrence of mucinous carcinoma

The survival rate for pure mucinous carcinoma of the breast is better than most other types of invasive breast cancer. In one study, the five-year survival rate of pure mucinous carcinoma is around 96 percent. When it’s mixed with other types of cancer, the five-year survival rate is 87 percent. This rate is for disease-free survival without a recurrence.

A more positive outlook is associate with several factors including:

  • diagnosis at an earlier age
  • good response to treatment
  • treatment involves less chemotherapy and more hormonal therapy
  • this type of cancer less likely to spread to lymph nodes or metastasize than other types

In a small 1992 study that followed 24 patients over a period of up to 16 years, the survival rate for mucinous carcinoma of the lung was 57 percent.

Mucinous carcinoma of the colon is usually not detected until the late stages. Therefore, the survival rate for this type of mucinous carcinoma is much lower. Your doctor will be able to best determine your outlook based on your individual test results.

These survival rates are guidelines. Your survival rate and rate of recurrence depend on many factors that are unique to you. Your doctor can give you a better idea of your specific outlook.

Symptoms of this type of cancer

In the early stages, mucinous carcinoma may not have any symptoms. But eventually, there will be a noticeable lump from the tumor. In the case of mucinous carcinoma in the breast, this lump may be felt during a self-exam or a doctor’s examination. Mucinous carcinoma can also be detected as a lump during a mammogram or MRI.

The tumor, or lump, is the main symptom of mucinous carcinoma. However, in cases affecting the breast, you may have additional symptoms of invasive ductal carcinoma. These include:

The primary symptom in the case of mucinous carcinoma of the colon is blood in the stool. However, this can be a symptom of other medical conditions so, be sure to talk to your doctor anytime you notice blood in your stool. You may have other symptoms similar to those of colon cancer in general.

The symptoms of mucinous carcinoma of the lung are the same as those for lung cancer in general.

Causes of mucinous carcinoma

The exact cause of many types of carcinomas isn’t known. However, there are several risk factors including family history of cancer and environmental factors.

Mucinous carcinoma can be a type of cancer in any part of the body that produces mucus. The risk factor for a particular mucinous carcinoma will depend on the area of the body it affects. Those risk factors will be similar to other types of tumors that affect the same area of the body.

Other common risk factors for cancer, in general, include:

  • age
  • gender
  • obesity
  • tobacco
  • sedentary lifestyle
  • alcohol
  • breast density (specifically for breast cancer)
  • unhealthy diet

Treatment options for mucinous carcinoma

Treatment options vary based on the area of the body the cancer is, the stage of the cancer at diagnosis, as well as other health factors. However, in most cases you will have either one or a combination of the following treatment options:

  • surgery to remove the tumor and any other affected areas
  • radiation therapy, which involves high-energy rays directed at the specific area of the tumor
  • chemotherapy, which uses cancer medication that targets your entire body, not just the area of the tumor, to kill cancer cells anywhere else they may have spread
  • hormonal therapy to block or lower the amount of estrogen (used in mucinous carcinoma of the breast)
  • other targeted therapies

Outlook

It’s important to get yearly checkups with your primary physician and regular OB-GYN appointments if you’re a woman. The earlier that mucinous carcinoma is found, the better your outlook and survival rate will be.

In the case of mucinous carcinoma of the breast, be consistent with breast self-examination to notice any lumps or other changes in your breast. Pure mucinous carcinoma has a better outlook than the mixed type in the breast.

Although the outlook for mucinous carcinoma of the lung, colon, and other organs isn’t as positive as it is for that type of tumor in the breast, early detection is key to a better outlook.