The discovery of a thyroid abnormality when clinical examination is a common situation.
If this nodule (s), patient anxiety is sometimes very present with filigree fear of cancer as the media, around the Chernobyl accident, have well maintained.
A FREQUENT LOCATION:
Prevalence of benign conditions:
We lack data on the prevalence of simple goiters. Remember that this is a homogeneous increase in volume of the thyroid gland, with no signs of dysthyréose. These simple goiters were typically more frequent in geographical areas of iodine deficiency: in France, Auvergne, Savoy, but also the Aisne, the Orne; and among our immigrant population: Kabylia.The iodization of edible salt as the movement of fruit and vegetables (we also eat Moroccan and Dutch tomatoes in Auvergne) have significantly reduced the problem. Kabylie region very deficient, yet provides many cases of simple nodular goiters. A recent French study found in 1108 women but not in men 792, an inverse relationship between the volume of the popular thyroid ultrasonography and serum selenium levels, and no relationship with the urinary iodine. But these measures point when the thyroid volume is more stable.
The prevalence of thyroid nodules is much studied.
In the adult population, it is, for clinically palpable nodules, between 2 and 8%. Attention to physical examination of the thyroid by GPs as their skill in such research plays an important role: some discover many nodules, others very little. The quality of the clinical examination is also variable among specialists and those who undertake an epidemiological study, conceived the disparity in published results, especially as a nodule of more than 10 mm in diameter, especially if to later development, may well be non-palpable
The female for thyroid disease is common.
The ultrasound nodule prevalence is much higher as expected. According to studies, it varies between 20 and 40% of the adult population. We are fortunate to have in France very recent data provided by the Suvimax nutritional prevention study.
On a perfectly representative sample of the French population across all our regions, this prevalence, established in 1461 men aged 45 to 60 years and 2,160 women 35 to 60 years is 14.5% (16.8% in women, 11% in men). It increases with age, from 12.9% in women 35 to 45 years to 19.2% between 45 and 60 years. In humans, the variation with age is less significant. More than 50% of identified nodules have a diameter greater than 10 mm, 10% a diameter greater than 20 mm. There are no differences between the five geographic regions: northwest, southwest, Île-de-France, northeast, southeast. These unique nodules in two thirds of cases.
We see a woman of fifty five carries nodule (s) sonographically detectable (s) This course outside any warning symptoms. Yet, ultrasound can not see everything, even in the hands of a trained professional because the autopsy prevalence is even higher, reaching 23 to 64% of the reviewed series. After 75 years, millimeter nodules are found in 100% of cases …
The classical notion of increasing prevalence of nodules with iodine deficiency is not found in the Suvimax study.Although nearly 20% of the urine indicate a deficiency (urinary iodine below 50 mcg / L), that these deficiencies are more frequent in the east than in the west of France, the prevalence of nodular pathology n ‘ is no different in the five major areas of division of the territory.
Prevalence of thyroid cancer:
The annual incidence of thyroid cancer was traditionally estimated between 1.2 and 2.6 / 100 000 men and from 2.0 to 3.8 / 100,000 women. This corresponds to a prevalence of around 0.1 to 0.35% of the population figures compared with the prevalence of sonographically detectable nodules.
But the fear of cancer and sometimes alarmist attitude of some colleagues or clinical imagers make this question dominates the problem of nodular thyroid pathology. The Chernobyl accident has had two consequences. One, unhappy, to increase the anxiety of each patient who has demonstrated a thyroid nodule. The other, beneficial to have stimulated research into the true incidence of thyroid cancer in France and fostered the establishment of a National Observatory.
It should immediately remember that the majority of thyroid cancer is made of papillary cancers (82% of cases in recent times) whose evolution is not always faster than the normal aging of the people who have it.
The study carried out at the initiative of the Health Watch Institute shows that:
– Only the annual incidence of this papillary cancer (the least “evil”) is increasing in France, from 1.49 to 4.53 / 100,000 between the periods 1978-1982 and 1993-1997;
– The curve is perfectly regular, absolutely not influenced by the Chernobyl accident;
– There is no increased incidence observed in children;
– The average annual increase over the period 1982-1996 was 7.5% in the department of Bas Rhin (overflown by the Chernobyl cloud) and 17.8% in the Tarn that has remained far away …
These critical data show firstly that serious cancers (follicular) or severe (undifferentiated) absolutely no increase, suggesting further that the increase in papillary cancers has many chances to be at least good partly linked to the progress of clinical screening, ultrasound and histological as we shall see later. The autopsy series have shown that the incidence of papillary microcancers below 10 mm or 1 mm diameter is very large, and their prevalence, similar whatever the average age and gender of autopsied series, suggests that they are not progressive and sometimes spontaneously regressive.
CIRCUMSTANCES OF DISCOVERY:
Very often fortuitously:
Sometimes it’s in occupational medicine or at a Social Security check, a careful physician detects the anomaly and asks the patient to see his doctor. Sometimes it’s the latter, performing a full review on the occasion of another pathology, who discovers the injury.
It is also sometimes dopplériste, during an examination of the neck vessels, which attracted the attention of a hitherto completely ignored or nodules.
Sometimes before symptoms:
This may be the results of a self-examination or self-inspection, the remark of a close: the lesion is visible, although a number of patients consulting for noticing “a big neck” have in fact a normal thyroid and a little too much subcutaneous fat.
This cervical abnormality can, while being totally painless, appear to be increasing in volume more or less rapidly.
It can also cause pain, local or regional inflammatory signs and can then be secondary to pharyngolaryngeal episode.
Moreover, the symptoms are related to thyroid dysfunction, rarely symptoms of thyroid insufficiency, usually those of hyperthyroidism emphasizing the dissociated tables that can be dominated or reduced to a tachycardia, a rhythm disturbance, diarrhea or softer stool, some degree of nervousness and irritability usual, or just a “form” not as good.
What explorations do?
The examination must include the patient’s geographic origin, that of both parents: the greater prevalence of goitre and nodular pathology in deficient areas is partly the result of a genetic selection that lasts long after the disappearance of deficiency. The presence of thyroid diseases in the family will sometimes established that at a subsequent consultation.
The seniority of the lesions is important to clarify: some patients in whom it has discovered a nodule actually know (and sometimes a bit forgotten) fact that they are carriers of an abnormality of the gland over twenty years, and it may be possible to recover the documents of the time.
We must of course specify the mode of onset of lesions and any accompanying signs: pain, inflammation, increase volume fast or not.
Finally, as always taking drugs iodine, lithium should be recorded although many sources of iodine overload are very difficult to highlight.
Clinical examination will search for signs of dysthyréose, hypo- or hyperthyroidism especially.
The inspection of the patient and her face, measuring heart rate by pulse palpation, the study of cutaneous vasomotor by inspecting neck skin and hands of palpation (dry, moist, hot or iced …), the skin of the chest that can be unusually hot, searching for earthquake-proof oath he must perform better to ask apart and outstretched fingers, some gestures may have already advanced his diagnosis.
It is obviously clear characters of the thyroid. If it is a homogeneous goitre apparently note its normal consistency, firm or flabby, and measure the neck, taken into hyperextension to obtain a reproducible measurement in time Homogeneous goitre rather flabby with euthyréose apparent evoke a simple goiter. A generally firm thyroid or hard, especially if there appear signs of hypothyroidism suggests Hashimoto’s thyroiditis.
If nodular goitre is, you have to map nodule trying to characterize each of its size in millimeters, its consistency, regularity. The existence of local inflammation, pain caused by palpation, cervical lymphadenopathy including earlier should be noted. So, suddenly appeared a nodule, round, very firm or hard like a ball, painless, evokes a thyroid cyst, a nodule recently swelled, sensitive or spontaneously painful, hard and a bit uneven shape strongly suggests otherwise irregular thyroid cancer, even in the absence of satellite nodes. A single nodule with signs suggesting hyperthyroidism can towards a toxic adenoma. A thyroid lobe or quickly became sensitive to sudden increase in volume and review signs of inflammation, a severe tenderness and significant lymphadenopathy evokes thyroiditis or push on strumite nodular goiter possibly earlier, situation beyond the scope of this chapter.
But in many cases, none of these signs suggesting is clearly present and what are the additional tests that will advance the diagnosis.
What additional tests?
In the absence of clinical element orientation, ask a dosage of thyroid stimulating hormone (TSH) and thyroid ultrasound. TSH sufficient to confirm or not the euthyréose, ultrasound is the only one able to properly anatomically balance, since even an apparently homogeneous goitre can conceal one or more nodules and that generally there has often more nodules than it appears clinically, even a skilled physician to palpate the thyroid. Some sonographic characters (purely cystic images, solid nodules regardless echogenicity surrounded by a well marked hypoechoic rim) are reassuring factors otherwise formal benignity.
Before a homogeneous goitre:
If there is an elevated TSH, usually very discreetly, dosage antibodies antithyroperoxydase witnessed Hashimoto’s thyroiditis which often gives a very firm goiter confirm the diagnosis. That there opposite a low TSH; be asked in addition to antibody antirécepteurs TSH to detect Graves pauci symptomatic disease.
In both situations, a dosage of 24-hour urinary iodine specify the possible deficiency (due to hypo) or overload (due to hyper as hypothyroidism) iodine.
Before a nodular goiter:
If there are signs of hyperthyroidism series, upon confirmation of a lowered TSH, ask a thyroid scan which this is the only indication. It will then confirm often a nodule is at least warm, more or less extinctive fixing the rest of the gland.It should also here to dose T3 and Free T4 to clarify the degree of hyperthyroidism.
In the presence of a thyroid nodule:
With clinical euthyréose and normal TSH, can request a determination of autoantibodies antithyroperoxydase, best witnesses of autoimmune thyropathie. You can also request a thyroglobulin (not thyroglobulin antibodies of little diagnostic value), or ACE or calcitonin, rare spinal cancer markers: these exams do not need to be performed routine.
In practice, the most important consideration is the thyroid FNA (Fig. 1, see also included in the color specifications).The technique must be strictly practiced with very fine needles of 0.5 mm in diameter, making several punctures by nodule, never aspire, and spreading immediately slide the droplet obtained. For twenty years, this examination has established itself as the best to differentiate a nodule Benin from cancer, and thus guide therapeutic indications.
Numerous published studies, the most important number is that of Ravetto et al. Which nearly 38,000 FNA established the sensitivity of the examination to 91.8% and specificity 75.5%. These figures vary according to the studies for the sensitivity that is at least only a little over 60%, specificity it is much more stable.
Anyway remember three things:
– Should be entrusted FNA to a trained practitioner;
– It must be read by a cytologist itself driven, reading and more pathology of thyroid cytology is the most difficult;
– Even so FNA remain non-contributory in at least 10% of cases. According to the clinical context, it should be or not be repeated.
That said, this practice significantly improves the diagnosis of thyroid nodules, the probability of cancer from 4% before to 0.4% if FNA cytology is declared benign and 90.7% if it concludes with malignancy . Research is currently underway to further improve the performance of the method using the techniques of immunohistochemistry.
the markings of the cytoplasmic thyroperoxidase and especially galectins 1 and 3 and dipeptylaminotransférase might be able to refine the diagnosis of benignity.
Goiter simple, homogeneous, euthyroid:
A simple monitoring enough, with at most clinical assay at the annual beginning of TSH. These situations are not rare in puberty: “My daughter, dawn touched your finger neck” (A. de Vigny). Goitre may regress past adolescence, but this is not mandatory. If goiter tends to increase in volume, we can discuss treatment “suppressive” (see below).
Nodule hot, extinctive:
In the most typical cases, the nodule is unique, frankly lowered TSH, T3 and / or a low free T4 and elsewhere there are clinical signs that often dissociated hyperthyroidism: it must operate and a simple nodulectomy cure the patient permanently. But things are not always so simple. Sometimes the characters of goitre, toxic multihétéronodulaire with one or more hot nodules, or age or unfavorable terrain make do prefer a more radical treatment which will total thyroidectomy or otherwise treated with radioactive iodine or antithyroid synthesis.
Elsewhere, extinctive nodule is not accompanied by clinical signs and T3 assays and free T4 are normal: simple monitoring of clinical and laboratory hormonal state may be sufficient as far as one can sometimes see toxic nodules regress event indeed exceptional. This simple monitoring is often the right solution if the nodule is hot but not extinctive. Again should be monitored clinically and hormonology but not to multiply the scans.
Purely cystic nodule:
Even if it is accompanied by ultrasonography other small cystic lesions, round and hard nodule clinically totally anechoic, deserves to be punctured, especially if it is sensitive.
We must warn the patient once evacuated, the liquid readily tea color, usually happen but usually in smaller amounts while not causing no discomfort.
Nodule full or cytologically not clinically suspect, euthyroid:
This is the most common case: there is no a priori indication for surgery
We can suggest a treatment called suppressive, or quiescence of the thyroid. Its purpose is to lower TSH levels without them out of the normal range and of course without causing clinical hyperthyroidism. Conventional practice uses levothyroxine at a dose of 50 or 100 mcg per day. A recent publication stresses the value of triiodothyroacetic acid at a dose of 1 mg per day, compared with levothyroxine, would obtain a greater reduction in the volume of goiter or nodules in a greater percentage (42%) cases with clinical and biological tolerance better. If this treatment, evaluated the clinical course (measurement of nodules, neck), and possibly the level of circulating thyroglobulin which must fall, walking, it should continue until the maximum effect. It will then be stopped.
With or without treatment “suppressive”, monitoring is the key to the therapeutic approach.
Clinical examination at least once every six months, TSH control annually at first, especially if there are antithyroperoxydase antibodies.
There is no interest by multiplying against ultrasounds: in the absence of new clinical element, an ultrasound every three years is more than enough.
What place can still have surgery? It remains low, you should know that a nodule initially Benin do not turn into cancer.
A cancer can develop in against his side and we have seen that rule, thyroid cancers are slowly changing. This means that the surgical indication is not related to fear cancer. It may sometimes be referred to the slow but steady increase of volume of the nodules, including testing despite suppression therapy, sometimes for aesthetic reasons. It is still sometimes because (the) patient (e) accuse goiter and / or (s) nodule (s) cause of cervical discomfort felt over time as intolerable.
This is probably the most debatable indication and must be well discussed with (the) patient: it is not uncommon for the surgery performed by the best hand leaves discomfort if compounded identically …
Clinically suspicious nodule:
It increased relatively quickly but not explosive volume basis. It is spontaneously sensitive or even a little painful. It is hard and a bit irregular on palpation It will of course perform a FNA. It is in these situations it is useful to ask a dosage of ACE and / or calcitonin. We have a good chance of being in front of a non-papillary cancer and surgical indication must quickly be raised.
Nodule clinically trivial, cytologically suspicious or malignant:
It should operate. No discussion but no urgency in the ordinary course of very differentiated cancers, papillary and follicular same. It is conventional to total thyroidectomy with dissection of proximity, followed after a month of administering a dose of 100 millicuries of radioactive iodine. The prognosis is generally excellent, replacement therapy is in good standing very easy to adapt, the survival of these patients did not differ from that of the reference population.
The few undifferentiated cancers are unfortunately a very rapid evolution, justifying and urgency and maximum surgery, with a poor prognosis.
Medullary cancer, also very rare also require full surgery with lymphadenectomy (very) extended. Their evolution is against highly variable, depending in part on the site of the mutation in the RET gene that assists in family forms. A survey conducted with tact and prudence allow detection of pre-forms whose prognosis after treatment is very favorable rule.
Some special cases:
Goiter, nodular or not, may be old but be discovered during a clinical picture of frank hyperthyroidism. This is the case of basedowifiés goitre whose processing returns to that of Graves’ disease.
The occurrence of an acute inflammatory flare is possible on a previously nodular goiter or thyroid. We are here in the context of a strumite. We must not go near a rare form of acute inflammatory undifferentiated cancer.
The finding harder than painful satellite nodes should worry. This possibility is eliminated is returned to the problem of treatment of subacute thyroiditis commonplace.
Finally, we can discover during a thyroidectomy or thyroid lobectomy, besides the expected microcancer a lesion. It is almost always a papillary lesion.
To the extent that this micro cancer is usually completely isolated, without break capsular and of course without lymphadenopathy, it is reasonable not to do anything, including whether surgery was only partial, and simply watched clinically (and sonographically) the patient monitoring by circulating thyroglobulin here being not efficient.
The nodular thyroid disease is very common. It is in a minority of cases to cancer, so the vast majority of differentiated cases, slow or very slow scalability and a well conducted treatment and not needlessly mutilating a cure. This is one reason for the physician to adopt an attitude that while many unnecessary alarm as keeping the patient to use an overabundance of unnecessary investigations, enable it by its simplicity and austerity specify diagnosis and to adopt an effective therapeutic approach.