 Hi there, my name is Jean-Clapper and I am a surgeon. One of my passions is medical education. In this series of presentations, I'll talk about things surgical. Remember, these presentations are available for continuous professional development points, so I leave the description to that down below. In this presentation, I'm going to talk about thyroid nodules. As we do more and more ultrasounds, we discover more and more thyroid nodules. In actual facts, some reports state that up to 70% of all patients will develop thyroid nodules. So in this presentation, I'm going to tell you what to do with this very common diagnosis. The nodules of the thyroid are amongst the most common histological disorders in the human body. Actually more than 70%, 70% of all humans will develop a thyroid nodule or even more than one nodule during their lifetime. This number keeps increasing with ever more sensitive imaging techniques and the incidence increases with age and there is definitely this female predominance. Most of these nodules of the thyroid are fortunately benign. This is so in at least 90% of cases and most patients will never ever be aware of them. Even some small cancers remain subclinical. Now fear response is triggered in most patients in whom a nodule is detected and it's our duty, the duty of the clinician to manage such a finding with great care. With nodules being so common and routinely seen on ultrasound imaging, it is important to know how to manage the patients with a thyroid nodule. We have to look at the different types of nodules. Now thyroid nodules may be colloid filled cystic lesions all the way over on the other side of the spectrum we find neoplasms. Now the latter are either benign, those are true monoclonal adenomas or follicular adenomas or they can be malignant. Now a combination of cystic and solid nodules are commonly seen and that happens in multinodular goiters. A nodule can be cystic to a varying degree from completely cystic, that's a true cyst with an epithelial lining but that's quite rare and then also over to only containing a small cystic component. Cysts are usually the results of a degenerative process of the solid component of a nodule. It is a rule of thumb that the malignant potential of a nodule decreases as its cystic component increases. Now that's relative to the solid component in the nodule. True monoclonal adenomas are the most common solid lesions of the thyroid. These can usually be identified on an ultrasound and on aspiration cytological examination and they are really benign lesions. Follicular new plasms, they can either be benign or malignant. Now cells seen on cytology for both benign and malignant follicular lesions appear similar and the diagnosis can only be made on histological evaluation of the surgically resected specimen. There are various types of thyroid carcinomas. These include papillary, follicular, hurdle cell, medullary and aplastic carcinomas as well as primary thyroid lymphomas. Yes, you can also develop a lymphoma in the thyroid. Now the true proportion of malignant lesions they really not known as it depends on how the incidence of nodules as a whole is described. If we only look at the incidence of clinically discovered nodules, then the incidence of carcinoma is going to be high. But of all true nodules of the thyroid, the incidence is pretty low. Let's look at the risk factors for the development of thyroid nodules. The most common risk factors are advancing age, the female gender, dietary iodine deficiency and a history of exposure to ionizing radiations such as radiotherapy of the head and neck. So the most common ones there really age and the female gender. Now these are not the only factors that put a patient at risk. The tobacco smoking, excessive consumption of alcohol and obesity are risk factors for many diseases including unfortunately also the development of thyroid nodules. Now the less commonly known risk factors are the presence of uterine fibroids, high insulin growth factor 1 levels and hematopoietic stem cell transplantation. So some of the rare risk factors there. Now thyroid nodules and cancers can be associated with familial disorders and it is important to inquire about a self or a family history of thyroid disease or cancer or indeed any endocrine conditions. Remember multiple endocrine neoplasias that's especially types 2A and B they are associated with medullary thyroid cancer. Now familial non-medullary thyroid cancer that's quite rare and it's really not that well defined. It is known to be associated with cardin syndrome, familial adenomatous polyposis, gardener syndrome, carny complex type 1, venous syndrome and DISA 1 syndrome. So all these are very rare conditions. Now some factors are associated with a decreased incidence of thyroid nodules so something that decreases the patient's risk of developing a thyroid nodule. Now these include the use of the oral contraceptive pool and also statins. Now unfortunately it's not currently known if these hormone formulations and medications are protective in any way though. We just know that it is associated with a lower incidence of thyroid nodules. Now size of the actual lesion that is a risk factor for malignancy and the larger they are especially after about two centimeters in greater diameter it becomes more likely to harbour a carcinoma. Clinical findings now depending on the clinical setting thyroid nodules are either diagnosed when they become visually evident so that's visually or through their symptoms or when seen incidentally during imaging for other conditions and most notably the common use of ultrasound these days. Now whilst a visible neck mass is common in some settings and yet others these nodules are palpable only so you don't see them by looking at the patient but can palpate them. Now some that are large enough especially those in the periphery of the gland can cause compressive symptoms involving the aerodigestive tract. Now these compressive symptoms are dysphagia, a dynaphagia, choking, this feeling of a squeezing sensation in the neck, a globus sensation that is the sensation of a mass or a lump or a foreign body in the throat that doesn't disappear by swallowing and then also dyspnea and some voice changes that subtle voice fatigue in cases of large nodules or actual voice changes due to nerve infiltration by a malignant process. Now the thyroid gland is visually inspected from in front of the patient, stay in front of the patient and we make note of any gross enlargements or asymmetry and then the thyroid moves during swallowing and remember all signs should be elicited by asking the patient to swallow. It's difficult when someone just asks you to swallow so it might be handy just to have a glass of water nearby. Now breweries and thralls they are not commonly seen in a thyroid nodules and they really may be indicative of other pathologies such as carotid aneurysms so watch out for those. Now the thyroid is palpated from behind the patient, once again asking the patient to swallow and then a note should be taken of any asymmetry and also the surface of the thyroid as well as its size, consistency, location and the movement of any masses. Looking on the patient's habitus and the clinician's experience with examination of the thyroid the finer changes may be missed, we all missed some of these, the finer changes that you find with these, the appearance of these nodules. Now at the very least we can take note of the following rule of thumb, bilateral enlargement with a smooth surface, smooth surface that's indicative of a goiter that's iodine deficiency or even Graves disease, a unilateral enlargement is indicative of a nodule so just feel that one side is bigger than the other that's probably a nodule and then an irregular surface and a normal size or an enlarged thyroid that's indicative of a multi nodule of goiter so that's just this rule of thumb and then nodules that are rock hard and immobile that means they fix to the surrounding structures that should raise the suspicion of a malignancy. Now malignancy can metastasize to original lymph nodes, we think about papillary thyroid carcinomas and also the jugular chain and we should really palpate these to feel for nodes. Now the famous Pemberton sign that you might remember that involves venous jugular engorgement, facial plethora and even dyspnea when the patient lifts their arms that's the Pemberton sign, we don't see that commonly but it's worthwhile to remember now that's caused by severe compressive symptoms due to a large retro sternal goiter. What about thyroid function test we all send off our patients off to the lab to get to get thyroid function test now we really have to make a special note of this most nodules are hormonally inactive but they can overproduce thyroid hormone in some cases and yet others they occur in the setting of hyperthyroidism such as that caused by Graves disease or in the setting of hypothyroidism such as caused by Hashimoto's thyroiditis so we really have to be a look in the lookout on the lookout for thyroid nodules in all of these on these cases now thyroid nodule in a hyper thyroid patient that necessitates the use of a centigram and that's to determine whether it's the nodule causing the overproduction or the underlying thyroid itself so yeah send away for your thyroid function tests so how do we work up these patients well the absolute minimum workup after discovering any thyroid nodule includes a thyroid stimulating hormone level that's number one and then a thyroid ultrasound and then further work up is determined by the results of these two investigations so thyroid function test and an ultrasound. Logistic regression analysis through research that's shown that patients with a normal TSH level those with the level just close to the upper end it's about 1.7 million inspilita they have higher odds ratio of malignancy than those that are still normal but at the lower end of normal so just something to remember so in the case of a suppressed TSH level that's hyperthyroidism overactive thyroid we do a thyroid syndrome with radioactive iodine isotope now the possible reporting will either be that of a hot nodule or a warm nodule or a cold nodule and the warm and cold ones they follow up as the same as someone with a normal TSH level so those with a hot nodule we don't really do any further work up for them because carcinoma just at least for investigating the possibility of a cancer it's very rare to have a hyperfunctional thyroid carcinoma. Now these patients with their hot nodules they are further evaluated for radioactive iodine therapy or surgery and then this includes the pretreatment of an antithyroid medication to manage their hyperthyroidism and unless there's a contraindication to surgery a thyroid or lebectomy and isthmus resection in the case of unilateral disease or total thyroidectomy in the case of bilateral disease that has a very high cure rate for this overactive nodule. Now hyperthyroidism they that occurs then in less than 3% of cases following a lebectomy and unilateral disease but in the case of radioactive iodine therapy if the patient chooses that that has a higher recurrence rate about 1 in 5 will have recurrence of their hypothyroidism. Now up to a half of patients they will also develop hypothyroidism within 10 years after the therapy so we have to follow these patients up long term. So then let's look at the patients that are euthyroid or hypothyroid. So they now go for the work up because we need to determine whether this nodule is malignant or not. Now the findings on ultrasound, ultrasound is our first investigation. The findings on ultrasound are classified by the American College of Radiologists using the Tyreds system and you get this kind of system now for many possible lesions in the body. Now the aim of the imaging classification system that's to reduce the incidence of biopsies on lesions that are highly unlikely to be of clinical significance. So we have the classification system from our radiology colleagues because we really don't want to to overdo things just to take by unnecessary biopsies and just increase the cost and the stress to the patient. We have the Tyred system here we look at a few the radiologists will look at a few things the composition the ecogenicity the transverse plane shape the margins and the ecogenic foci in this lesion and points our given for those those are then tallied and we get we get the result. What we have is a Tyreds 1 2 3 4 5 and a Tyreds 1 that's really a benign. 2 is a non suspicious lesion 3 is mildly suspicious 4 is moderately suspicious and 5 is then highly suspicious. So for benign we don't do any further work up there's no fine needle aspiration cytology required and also for a Tyreds 2 for a mildly suspicious lesion that's type 3 we can really follow that patient up for a year a year 1 year 3 and year 5 and that is if the lesion is less than 25 millimeters in greatest diameter if it's more than 25 millimeters in greater diameter we do a fine needle aspiration cytology. When we get to moderately suspicious that's Tyreds 4 we also follow the patient up on years 1 3 and 5 and that's for lesions less than 15 millimeter they 15 millimeter more fine needle aspiration cytology. When it comes to Tyreds 5 if the lesion is less than a centimeter in greatest diameter we can do a follow-up of these lesions they small and we're not sure of their clinical significance and if they are greater than a centimeter though they get fine needle aspiration as well so that's how we use the Tyreds system so let's look at the fine needle aspiration cytology that is performed under ultrasound guidance and we use a small 25 or 22 or 27 gauge needle and that's inserted right into the lesion and then the refinings are reported by our pathology colleagues using the Bethesda system for reporting thyroid cytopathology and there are six classes described using this Bethesda system now a class one that the class identify samples that are not amenable to psychological examination we see that put the needle in and it's unfortunate bloody aspirate and we can't make a diagnosis on that there's this inadequate sampling it is also seen when lesions are particularly cystic sometimes it's impossible to obtain a good sample in the case of the latter clinical judgment must be used to decide between a lobectomy and interval observation and we usually do that according to the Tyreds then into according to the size now most cases a repeat aspiration will need to be done and it usually yields a proper sample now it's best to do this in the setting then where the aspirate can immediately be examined in the presence of a pathologist where they can look for adequate follicular cells so sit by the patient and we take those final aspiration cytology have it looked at immediately not to make the diagnosis but just to make sure that there are follicular cells that can be examined now remember this advice at three months past before repeating the final aspiration so you can't just do it the next week unless there's a very high suspicion of malignancy then we then we can do it sooner but it is advised to to have three months in between those final aspirations for class two that's clearly benign pathology in an adequate sample and that's the most common diagnosis then is that of a benign colloid nodule with benign appearing follicular cells and an abundance of colloid so this colloid cell ratio and the more colloid with adequate cells that really tells us that it's benign now care should be taken to ensure that the sample was representative that it wasn't taken outside of the nodule because there's a false negative rate and then the American Thyroid Association they advised that all patients should have a follow-up ultrasound within the following year to document growth even if it is this Bethesda 2 so growth we define that as an increase of 20% in at least two dimensions so the repeat aspiration for cytology should be done in all cases of growth as well as in cases with the new compressive symptoms or visual enlargement or appearance of new nodules then we're gonna do it in FNA and again again if there's no growth identified and we can just repeat the ultrasound examination with an interval of about two years it must be remember though that benign lesions can actually grow too so you might repeat those biopsies and it is again it's again benign even even though they've grown so for class 3 that's either cellular atypia or a follicular lesion with undetermined significance so those are both class 3 now the incidence of carcinoma in this class is unknown since most of these cases do not come to soji we don't operate them and the true rate of malignancy is therefore unknown it repeat aspiration for cytology is one possible choice now if the class diagnosis persists then we'll do a lobectomy which should really consider lobectomy an isthmus resection then and in advanced areas we get molecular molecular testing these days it's becoming more widely available and if it is we'll do that for classes 2 to 5 so if we test the 4 that is a follicular neoplasm that the sheets of follicular cells that's seen with with a paucity of colloid so there's many more cells as a cellular colloid ratio that goes in the favor of being much more cellular now the malignant potential of a follicular neoplasm we can't see that on cytology because the architecture the cellular architecture with the tissue architecture should say is not preserved with a with a final aspiration now we really need that architecture the tissue architecture in the evaluation because we need to look for infiltration to make this a follicular carcinoma and how to manage these well exactly the same as class 3 we get to class 5 as really suspicious of the malignancy and surgical resection is really advised now for lesions less than 4 centimeters without lymph node enlargement or any high grade pathological findings we can do just the lobectomy an isthmus resection but in all other cases will do a total thyroidectomy 6 then it's very clearly malignant and these include papillary carcinomas it's you can diagnose papillary thyroid cancer on a final aspiration you don't need you don't need the tissue architecture now it must be noted that surgery can proceed irrespective of a low but test a class patients with benign disease may not be able to live with the compressive symptoms or they may prefer surgery for cosmetic reasons reasons that's important to discuss the possible complications of subtle or more profound voice changes due to nerve injury and the risk of hypothyroidism and with all the patients so that they can make an informed decision that is best for them it is just as important to consider patient comorbidities both current and future and it might be proven to operate before comorbidities naturally worsen with age and a higher incidence of developing with age so we really got to take all these things in consideration and discuss these with the patients so they can make decision that is really best for them now the guidelines are really unclear as to how long to follow a patient with benign final aspiration cytology and then many are seen yearly with repeat ultrasound and aspiration biopsies and they might just become sick of the situation and they might decide on on surgery as well now what to do with these cystic lesions now as we've mentioned some modules are predominantly cystic in nature most of them form from a degenerating adenomas they just degenerate and the majority are benign although malignant cystic lesions they do exist are a but they do exist now purely cystic lesions do not require final aspiration you see an ultrasound can clearly see that this is a cystic lesion and don't really need a final aspiration cytology of that now you can aspirate the cyst to dryness if they are large and they come have compressive symptoms the patient has compressive symptoms now the aspirate this we do send that for cytological evaluation and the results are managed accordingly assist that recur after repeated aspiration or remain present after aspiration especially if they symptomatic pain or compressive symptoms that can be managed by surgical lobectomy fortunately there's not many of those patients but we really can't consider the surgeon setting now the same can be said for cysts that are a diagnostic dilemma we get these mixed solid cystic nodules and in those cases they just manage them as if they are just purely solid nodules so in conclusion the entire nodules are commonly seen in all our medical practices now patients should be investigated number one for hyperthyroidism that's the number one so you send away your TSH if that's low that's hyperthyroid patient and they should undergo a scintigraphy if it's a hot nodule they require lobectomy and if it's warm or cold nodule they just treat it the same as the euthyroid or hyperthyroid patients and those that are then euthyroid or hyperthyroid they get an ultrasound and based on that they'll get a final aspiration cytology and then we decide between surveillance and surgery and then the highly suspicious ultrasound or cytology classes they are managed by surgical resection and careful follow-up it's really planned in all other cases so your thyroid patient really stays with you and you do follow them up over a long period of time as with most thyroid diseases the thyroid or pathology of the thyroid changes with time and we need to to monitor those patients please remember that this video series is part of a program of continued medical education and the information for that will also be in the description down below