Saturday, May 24, 2008

What is Thyroid Cancer Ultrasound Lymph Node Mapping, and why do I need to have one BEFORE my Cancer Surgery?

Prior to the new approach to thyroid cancer, the radio-iodine whole body scan WBS, was the mainstay of diagnostic cancer studies. Along came highly sensitive cancer markers, Thyroglobulin TG, and the TG antibody. The WBS was poor at detecting recurrence. The addition of the newer high frequency ultrasound was better at finding recurrences, than the WBS. With Cancer markers and Ultrasound we can find the cancer that is missed with WBS, and even after a post treatment scan. The lymph node mapping by high frequency ultrasound can find tumor recurrence even when the WBS, TG and PET/CT are negative! Well if it is that good after the surgery, maybe it is good PRIOR to the original surgery. In fact if you have a qualified clinical thyroidologist, and thyroid ultrasonographer map your neck BEFORE the original surgery, it will expand the scope of the first surgery in 20-30% of the patients with a positive needle biopsy confirming cancer or is suspicious of thyroid cancer. The expanded surgery would include the lateral neck nodes on the side of the positive node biopsy. Modern thyroid cancer pre-op should include a lymph node mapping. INSIST on one before the surgery.It will save you another surgery in 1-5 years. The first surgery is the most important. Recurrences will be less likely if positive nodes, which would be still left in the neck were not removed at the original surgery. The use of MR,CT or PET/CT will not be as accurate as Ultrasound in the right operators hands at finding your neck node disease. Ask your endocrinologist or internist to refer you to an endocrine neck ultrasound lab where a clinical thyroidologist, and ultrasonographer can help him. My referral endocrine neck ultrasound lab website is www.endocrineneck.com.

Case Presentation:

56 Y/O female was seen 6 weeks after total thyroidectomy for a needle biopsy proven papillary thyroid cancer. The internist sent her for management of the cancer, after the surgery. The cancer marker on Thyroid hormone was <0.1, and the TSH was 0.09. However the lymph node mapping found cancer nodes in the right neck. The ultrasound guided FNA biopsy was negative for cytology, but was positive for TG in the washings from the largest node. It is common that the cytology will miss the tumor , but the TG will be found in the node. Any TG in the node is abnormal.The patient was shocked that a node study was not done before the first surgery. I told her it was relatively new information,and not well known by non-specialists. The patient was sent back to surgery to do a modified neck dissection. 4/15 nodes were positive for metastatic thyroid cancer in the neck.

The best time to send a patient to the clinical thyroidologist is when the nodule is first found, not after the biopsy, and surely not after the crucial first surgery.

Good Luck,
Dr.G.

No comments: