MRA Thought of the Day – Sentinel Nodes: Breast Cancer Cases
For breasts cancer cases, should you count sentinel nodes as ipsilateral axillary nodes for data field CS SSF3 and CS SSF19?
Here are my thoughts…
Sentinel lymph node: the hypothetical first lymph node or group of nodes draining a cancer.
In CS version 1, data field CS SSF3 was called Number of Positive Ipsilateral Axillary Lymph Nodes. In CS version 2, the content has been modified to limit the count of axillary lymph nodes to Level I and Level II on the same side of the body as the primary site. These nodes are the low axillary (Level I and intramammary) and mid-axillary (Level II, also called interpectoral or Rotter’s nodes). Include only the number of positive ipsilateral Level I and II axillary lymph nodes and intramammary lymph nodes in this field and note that it is based on pathologic information only.
The number of positive Ipsilateral Level I-II axillary lymph nodes determines the N category and the pathologic stage group. The structure of this 3-digit field is similar to the 2-digit field Regional Nodes Positive, and the same coding rules apply to both fields.
CS SSF19 Assessment of Ipsilateral Axillary Lymph nodes provides supplemental information on how the number of positive Levels I and II (and intramammary) lymph nodes was determined for CS SSF3, the N category, and the stage group. The purpose of this field is to divide the CS SSF3 results into sentinel nodes exam vs. axillary node dissection combinations.
If pathology report only states “sentinel node” and not otherwise specified as “sentinel axillary node”, can we presume that the otherwise unidentified sentinel node to be Level I/II ipsilateral axillary node?
Since sentinel node is the first lymph node or group of nodes, we can presume that the sentinel node belongs to the axillary lymph node chain. According to the most recent CAP Protocol, an intramammary could rarely be the sentinel node. The sentinel nodes are counted just the same as Level I/II axillary node.
Here are a few examples:
- FNA left sentinel node: positive for mets.
Left axillary node dissection: 00/05 left axillary nodes.
CODE: CS SSF 3 as 095
CS SSF 19 as 025
- Right Level I axillary nodes dissection: 02/06 positive for mets
CODE: CS SSF 3 as 002
CS SSF 19 as 123
- FNA right sentinel node: 01/01 positive for mets
Right levels I and II axillary node dissection: 05/05 positive for mets.
CODE: CS SSF 3 as 005
CS SSF 19 as 027
Reminder: For CS SSF3 – Do count a positive aspiration or core biopsy of a lymph node in the same lymph node chain removed at surgery.
- Left sentinel and non-sentinel axillary lymph nodes dissection: 08/10 positive for mets.
CODE: CS SSF 3 as 008
CS SSF 19 as 070
- Recent diagnosis of right ductal carcinoma with positive nodes.
CODE: CS SSF 3 as 097
CS SSF 19 as 150
In conclusion, positive sentinel lymph nodes on the same side of the primary breast is considered as ipsilateral axillary lymph nodes when counting the positive nodes for coding CS SSF 3.
What are your thoughts?