The other comments here are incorrect. This patient has no symptoms other than a solitary mass 2-cm lateral to midline that moves with swallowing.
Thyroglossal duct cysts are THE MOST COMMON mass within 2-cm of midline, but can be more lateral as well. 2nd most common is dermoid cyst. Thyroid nodules and TGDC's are the only 2 masses that move with swallowing.
Fine-needle aspiration (FNA) is often used to diagnose TGDCs or to exclude other diagnoses (such as thyroid nodules, bronchial cleft cysts, etc.). THIS IS WHY it is the correct answer. The other answer choices would be next best step DEPENDING on the results of the FNA.
charcot_bouchardThank you...Kudos to step prep for his contribution but i often find him taking serpentine turns to bypass the "Why I was wrong" part.+1
merpaperple"The other answer choices would be next best step DEPENDING on the results of the FNA." I don't think that's quite right. The "next best step" in this question would likely be to do US/check TSH. If there are highly concerning features for thyroid cancer or a normal TSH, then you would do an FNA. If the TSH is low then you would do RAIU to confirm that it's a "hot" nodule (and from there you would do an FNA only if the nodule is "cold" rather than "hot"). I think the reason that FNA is the correct answer here is because the question was asking what is "most likely to ESTABLISH A DIAGNOSIS," not next best step in management. Even if FNA is totally inappropriate to do before you even get an US, theoretically it would probably tell you exactly what you are dealing with more than any other study.+2
azibird^^^I think merpaperple's comment is the key here. Quick diagnosis = FNA, although this is not the best next step like we are trained to select. But also screw you NBME because if it's a follicular thyroid adenoma then you'll need to excise the entire capsule to distinguish from a follicular carcinoma.+
Young woman with a nontender thyroid mass/nodule that is 2 cm in size, requiring fine needle aspiration biopsy
Key idea: All thyroid nodules should be worked up with a TSH and thyroid ultrasound, with thyroid nodules greater than 2 cm in diameter or thyroid nodules greater than 1 cm with high-risk sonographic features (irregular markings, microcalcifications, etc.) should undergo fine needle aspiration biopsy
Key idea: The thyroid gland is highly vascular, which is why you would always use a fine-needle aspiration biopsy for evaluation
Key idea: Mass in the neck that moves with swallowing = Thyroid or thyroglossal duct cyst
Key idea: Hypofunctional or “cold” thyroid nodule has a higher risk of malignancy as compared to a hyperfunctional “hot” thyroid nodule
ht3sooo you're saying to get TSH first...so why would the answer not be thyroid function tests..?+3
nbmesuxughI thought that too but the question is asking to establish the diagnosis not the next best step! just be careful on test because I have seen tricky questions like that +11
submitted by kalam(10)
The other comments here are incorrect. This patient has no symptoms other than a solitary mass 2-cm lateral to midline that moves with swallowing.
Thyroglossal duct cysts are THE MOST COMMON mass within 2-cm of midline, but can be more lateral as well. 2nd most common is dermoid cyst. Thyroid nodules and TGDC's are the only 2 masses that move with swallowing.
Fine-needle aspiration (FNA) is often used to diagnose TGDCs or to exclude other diagnoses (such as thyroid nodules, bronchial cleft cysts, etc.). THIS IS WHY it is the correct answer. The other answer choices would be next best step DEPENDING on the results of the FNA.