Invasive ductal carcinoma, or IDC, is a type of breast cancer that develops from the ducts of the breast--the tubes that connect the milk-secreting lobules to the nipple. IDC is the most common form of breast cancer, accounting for around 80 percent of breast cancer diagnoses, according to BreastCancer.org. IDC is characterized by its ability to invade neighboring tissue and travel throughout the body, forming secondary tumors in distant tissues in a process called metastasis. A few tissues are commonly a site of IDC metastasis.
Bone Tissue
Bone tissue is a common site of breast cancer metastasis, according to a study published in the World Journal of Surgical Oncology in 2010. Bones are made up of a mineralized outer later, with larger bones containing other tissue at the center, called bone marrow. The mineralized layer of bones is constantly undergoing cellular turnover: Certain cell types deposit new bone tissue, and other cell types break down old tissue. IDC metastasis to the bone can disrupt this process and can lead either to an increase in bone mass and the growth of bony projections, or to increased bone breakdown leading to bone weakness.
IDC patients with bone metastases will often experience joint pain due to cancer growth on previously healthy bone tissue. In some cases, the bone weakens to the point that it is fragile and prone to fracture, which leads to patient injury.
Lung Tissue
IDC can also commonly metastasize to the lungs. A study published in the Japanese Journal of Clinical Oncology in 2008 indicates that 60 to 70 percent of breast cancer patients who die from the disease have secondary tumors in their lungs, and that the lungs are the only site of metastasis in 21 percent of breast cancer cases. Metastasis to the lungs can be fatal, since tumor growth leads to the development of life-threatening symptoms.
IDC patients with lung metastases experience difficulty breathing due to decreased lung capacity, and patients may also cough up bloody sputum from tissue damage as a result of tumor growth.
Liver Tissue
IDC also commonly metastasizes to the liver, according to a study published in the Journal of Cancer Research and Therapeutics in 2009. The liver normally functions to aid in digestion and to help detoxify the body. When IDC cells invade the liver, the resulting tumor growth impedes liver function and causes a number of harmful side effects. Patients may notice pain in the upper right quadrant of the abdomen, corresponding to pressure on surrounding organs from tumor growth in the liver. Patients may also experience a loss of appetite, weight loss and night sweats. As the liver begins to fail due to IDC metastasis, chemicals from the liver begin to circulate throughout the body, causing a yellowing of the skin and eyes, called jaundice.
References
- BreastCancer.org: IDC - Invasive Ductal Carcinoma
- National Institutes of Health: Clinicopathological features of infiltrating lobular carcinomas comparing with infiltrating ductal carcinomas: a case control study.
- Japanese Journal of Clinical Oncology: Risk Factors for Initial Lung Metastasis from Breast Invasive Ductal Carcinoma in Stages I--III of Operable Patients
- Journal of Cancer Research and Therapeutics: Epitrochlear lymph node metastases from invasive ductal breast cancer
