There are some significant differences between non-invasive and invasive breast cancer – time to find out
Did you know that there are two main types of breast cancer?
Invasive and non-invasive.
For more information on this, do the following:
- Read this article from start to end
- Schedule a consultation with Dr Yunaev, one of the top surgeons in NSW
In this article, we will cover all you need to know including:
- The difference between each form of breast cancer
- The types of each cancer
- What you should do next
Let’s dive in.
Who is at risk from these types of cancer?
Unfortunately, the primary risk factor is being female as men rarely develop breast cancer. Other categories at risk include:
- Early menstruation (younger than 12)
- Late menopause (older than 55)
- Older ages
- Mutations in the BRCA1 and BRCA2 genes
- Dense breast tissue
- Caucasians
- Family history of breast cancer
- Previous chest radiation therapy
What are the symptoms of invasive and non-invasive breast cancer?
Symptoms can include:
- Lumps in the breast
- A change in size, shape, or appearance of the breast
- Thickening or hardening of the breast
- Swelling of part or all of the breast
- A nipple discharge that isn’t breast milk
The best way to determine the presence of breast cancer is with a mammogram and ultrasound. This is recommended regularly to catch breast cancers before they develop.
How do you diagnose invasive or non-invasive breast cancer?
A biopsy is the best way to diagnose breast cancer. This will take a sample of cells and make it possible to identify the type and grade of cancer. This information is crucial to help guide your treatment plan.

There are various ways to assess the breasts to determine if cancer is present.
How do the types of non-invasive and invasive breast cancers compare?
There are several different subtypes of invasive and non-invasive breast cancers. Here we will focus on some of the common ones.
Types of non-invasive breast cancers
These are several subtypes of pre-invasive breast cancers, which are a collection of abnormal cells in the breast that may eventually become invasive breast cancer. The two most common ones are:
Ductal carcinoma in situ (DCIS)
This refers to abnormal cells developing within the ductal tissue and they have not invaded into the rest of the breast or spread to other tissues. DCIS may become invasive over time, which is why treatment is usually recommended.
Classic Lobular carcinoma in situ (LCIS)
The difference here, when compared with DCIS, is that abnormal cells are within the lobules and not the ducts. As they are not invasive they refrain from growing through the walls of the lobules. Classical LCIS is not considered cancer, but rather a risk factor for developing breast cancer in either breast in the future. Other subtypes of LCIS may behave more similarly to true pre-invasive cancer, similar to DCIS. Therefore, these patients need to be monitored with a more frequent interval or may consider risk-reducing treatment.

This image shows (A) DCIS and (B) LCIS, both of which show evidence of malignant cells in the basement membranes. Image Ref: https://teachmesurgery.com/breast/malignant-disease/breast-carcinoma-in-situ/
Types of Invasive Breast Cancers
There are many different types of invasive breast cancer, the 2 most common types include:
Invasive ductal carcinoma (IDC)
This is the most common type of invasive cancer, making up roughly 8 out of 10 of all breast cancers. IDC begins in the ducts and then spreads to nearby breast tissue. If not treated, it can spread to the lymph nodes or other areas of the body.
Invasive lobular carcinoma (ILC)
ILC varies slightly as it makes up about 1 in 10 breast cancers and starts in the lobules then invades nearby breast tissue. If not treated, this cancer can spread to the lymph nodes or other areas of the body.

Invasive cancers can grow inside a normal, healthy tissue and then continue to metastasise to other distant areas from the original location. Image Ref: https://lobularbreastcancer.org/imagingilc/
What is the best treatment for invasive and non-invasive breast cancer?
Treatment for invasive breast cancer usually involves surgery, and the stage of cancer will determine how aggressive that is. The most common options are a lumpectomy or mastectomy. Surgery on the Axilla (armpit) may also be necessary.
The Lumpectomy removes the tumour and surrounding tissue and is often followed by radiation therapy. Oncoplastic procedures can be combined with a lumpectomy to help achieve a good aesthetic outcome to the breast after cancer resection, to avoid divots and deformities or to avoid a mastectomy with a larger breast conservation procedure.
A Mastectomy on the other hand removes the entire breast (through a range of different types of mastectomies which may allow preserving more of the breast skin envelope for a better aesthetic result), which can then be reconstructed with a range of breast reconstruction surgery options.
What does it mean when breast cancer is invasive?
Invasive cancers can grow inside a normal, healthy tissue and then continue to metastasise to other distant areas from the original location. Breast cancer usually begins in the cells of the milk-producing glands or the ducts. A pathology and radiology investigation will be required to determine whether or not cancer has spread from the area where it started.
What does non-invasive cancer mean?
Non-invasive cancers will stay within the milk ducts or lobules and do not grow or invade the normal tissue beyond the breast. These cancers are referred to as pre-invasive carcinomas.

This is an example of a young woman undergoing nipple-sparing mastectomy on the right and skin-sparing mastectomy on the left and immediate reconstruction with implants.
Who am I and How can I help?
My name is Dr Michael Yunaev, and I am passionate about helping women regain a sense of normality after cancer. As a Specialist Breast (Oncoplastic) and General Surgeon, I have many years of practice and experience and expertise in the field of breast cancer.
I am also an expert in breast preservation and breast reconstruction and offer a range of techniques to help those with any form of breast cancer to feel more confident and have a good quality of life.
FAQs
To learn more about some of the frequently asked questions about each type of cancer, read this section:
Why do I need to know the difference between invasive and non-invasive cancer?
It is important to know whether the cancer is non-invasive or invasive as this will determine the treatment options available. This will also give some idea as to how the patient may respond to the treatments they receive and the likely prognosis of the disease.
What is the most common type of non-invasive and invasive breast cancer?
The most common non-invasive cancers are called DCIS (ductal carcinoma in situ). For invasive breast cancer, IDC (invasive ductal carcinoma) is the most common type.
Which type of breast cancer has the best prognosis?
Pre-invasive cancers have a better prognosis than invasive ones. Once the cancer is invasive, the prognosis will depend on its biological characteristics and its stage. The earlier the stage and more benign characteristics the better the prognosis.
What is the most difficult breast cancer to treat?
Triple-negative breast cancer is the hardest to treat, however, it is also the least common form of breast cancer.