Diagnosis
Breast cancer may present as a symptom, such as:
- A lump
- Nipple discharge
- Nipple retraction
- Skin tethering (change in breast shape)
Commonly, early on, there may be no symptoms and breast cancer may be found on a mammogram or ultrasound as a mass or other abnormality. The diagnosis of breast cancer is usually confirmed via a needle biopsy. The most reliable needle biopsy is either a core or vacuum needle biopsy which involves obtaining a core of tissue. However, sometimes the diagnosis may be made on fine needle biopsy where cells are extracted individually and in small groups through a smaller needle.
Types of Breast Cancer
There are a variety of types of breast cancer, with most falling into two large groups:
- Ductal – about 80% of breast cancers
- Lobular – about 10% of breast cancers
The remaining 10% are made up of special types including:
- Tubular
- Medullary
- Mucinous
- Papillary
- Micropapillary
- Metaplastic (squamous cell, neuroendocrine)
Invasive vs in situ and other features
Most breast cancers are invasive meaning that they have penetrated the wall of the duct or lobule. Sometimes breast cancer may be picked up earlier, before it has broken through the wall all the duct and this is termed in situ cancer. In the milk duct this is called ductal carcinoma in situ (DCIS). Lobular carcinoma in situ (LCIS) is not regarded as carcinoma itself but more as a marker for higher risk of developing breast cancer later and not necessarily at the site of the LCIS.
The above types are based on what is seen under the microscope, however every cancer is subtly different and the treatment of breast cancer is based on other features including whether it is oestrogen sensitive, how fast it is growing and whether there is evidence of further spread to other areas like the lymph nodes. Therefore breast cancer treatment is individualised for each patient based on the type and features of their particular breast cancer.
