Video Transcript:
CancerBro, how is the staging of breast cancer done?
The staging of breast cancer is called TNM staging. We will discuss this in detail.
It is called as T1 when the tumor size is less than or equal to 2 cm.
T2 when the tumor is 2 cm to 5 cm. And T3 when the tumor is more than 5 cm.
To understand T4 disease, first we have to know the structures.
Deep to the breast there is pectoralls fascia and pectoralls major muscle.
And here lies the pectoralis minor muscle. Other structures in the chest wall include ribs and intercostal muscles.
If we look from the front of the chest, this is the pectoralis major muscle. And this is the serratus anterior muscle.
T4a disease is when the tumor inflirates the chest wall, not including only pectoralis muscle adhesion or invasion.
And here, the tumor infiltrates into the serratus anterior muscle.
T4b disease is involvement of skin by the tumor. It can present as skin ulceration or as satellite tumor nodules.
Or as edema of skin looking like an orange peel known as peau de orange. All the skin changes should occupy less than one-third of the surface area of breast to be called as T4b.
Infiltration of tumor into both, chest wall and skin, i.e., T4a and T4b both, is called T4c.
And when the breast cancer progresses very rapidly to cause diffuse erythema and edema of skin breast, involving more than one-third of the skin, then it is called as inflammatory breast cancer.
Now, we move on to the N-staging. To understand the N staging, first you have to know the local structures in that area. In this figure, you can see the humerus, clavicle and sternum bone. This is the pectoralls minor muscle.
These nodular structures in the anterior axillary fold, are called as anterior group of lymph nodes.
And along the head of the humerus are lateral group of lymp nodes. All these three groups, lateral to pectoralis minor muscle, are level 1 lymph nodes.
These present behind the pectoralls minor muscle are central, or level 2 lymph nodes.
And these present medial to pectoralls minor muscle, are apical or level 3 lymph nodes.
And these, along the sternum are called as internal mammary lymph nodes.
For clinical N-staging, we have to palpate level 1 and 2 lymph nodes in axilla. If they are not palpable, it is NO. If palpable, and freely mobile, it is N1.
If level 1 or level 2 lymph nodes are palpable, but they are fixed or matted, it is called as N2a.
If only internal mammary lymph nodes are seen in CT scan without any level 1 or level 2 nodes, the it is called as N2b.
If infraclavicular lymph nodes are involved, it is called as N3a. If internal mammary ans axillary lymph nodes both are involved that is N2a and N2b, then it is N3b.
Involvement of supraclavicular lymph nodes are called as N3c.
Read the complete transcript here: https://youtu.be/XEBQ0lq67kM
