Thyroid surgery: Lymph node sampling
Will lymph nodes be sampled during the operation?
Lymph nodes are small glands throughout your body that collect any fluid, infection, or cancer cells. Each group of nodes is responsible for a particular body part. For example, groin lymph nodes are responsible for the legs and axillary (armpit) lymph nodes are responsible for the arms, upper chest, and breast. The head and neck area has a rich and organized lymphatic system with over 300 lymph nodes around the jaw and neck.
The lymph nodes in the neck are divided into six or seven compartments. Surgical resection of these lymph nodes (lymphadenectomyLymphadenectomy - surgical removal of lymph nodes) should be performed in an organized manner, by removing lymph nodes from specific compartments which are documented or likely to contain metastatic cancer. This minimizes the risk of leaving cancerous cells behind. Central neck lymph nodes are those directly under or very near the thyroid, and are sometimes removed during thyroidectomy depending on the type of cancer. Sometimes the central neck lymph nodes can only be seen after the entire thyroid is removed, so the surgeon often decides whether to leave or remove these specific lymph nodes during surgery. Lateral neck lymph nodes are near the jugular veins and would only be removed if they were found to contain metastasesMetastases - spread of cancer during pre-surgical imaging.
Patients having thyroid surgery for PTCPTC - papillary thyroid cancer should have a preoperative ultrasound of the lymph nodes (i.e. lymph node mapping) on both sides of the neck since thyroid cancer can spread outside of the thyroid and involve these lymph nodes. If any lymph nodes look suspicious, an ultrasound-guided FNAFNA - fine needle aspiration biopsy biopsy of the lymph nodes should be performed prior to surgery.
If the ultrasound findings and the FNA are consistent with cancer in the lymph nodes, a neck dissectionNeck dissection - removal of the cancerous lymph nodes and surrounding lymph nodes in that region (removal of the cancerous lymph nodes and surrounding lymph nodes in that region) should be performed at the time of the thyroid surgery.
If the ultrasound and/or biopsies of the lymph nodes are not concerning for cancer, the lymph nodes likely will not be removed. However, during the operation, the lymph nodes surrounding the thyroid gland will be inspected and any abnormal lymph nodes would be removed and biopsied. If any of the lymph nodes contain cancer, a neck dissection would then be performed.
For patients having thyroid surgery for a benign condition, lymph nodes in the vicinity of the thyroid gland will be inspected but are not routinely sampled or removed.