Hot nodules

Graves disease Hot nodule and toxic multinodular goiter Etiology ... 

A euthyroid subject with an autonomous adenoma (hot nodule) becomes hyperth)n-oid if given iodide. 

Fig. 7.1. High iodinated contrast uptake in liver tumours can be seen during angiography in those lesions with hypervascularization (a). In the same patient, hepatic nodules can be identified in the planar scintigraphy after MAA infusion as areas of focal uptake ( hot nodules ) spread in both lobes. The rest of the liver (non-tumoral) presents faint uptake of the...

Surgical removal of parts of the thyroid gland ( hot nodules or tumour tissue)... 

Table I Count rate per 100 seconds in Koc iodine peak in solitary "hot nodules...

XRF scanning of the thyroid very clearly demonstrates this differentiation in human glands (10).. The classical heterogeneity of simple goiter as seen upon scintiscans, already by itself a reflection of the phenomenon, is also found by XRF, but not necessarily with comparable distribution.. Some non-toxic hot nodules contain non detectable amounts of stable iodine (Figure 1).. 

Iron is a common constituent of marine sediments. Magnetite is found in beach sands and iron is coituuoti in glauconitic manne silicates. Iron oxides and sulfides occur where anaerobic conditions and elevated temperatures arc found, as in the hot. salty brines found near rifts. Iron is a major constituent of the ferromanganese nodules. 

Histoplasma capsulatum var. duboisii causes African histoplasmosis, skin manifestations being the prominent sign in this variant. Three patterns may be differentiated clinically superficial (ulcerating papules or nodules, infiltrated plaques, target phenomenon ), subcutaneous granulomas (first hot and tender, then cold, rupture) and osteomyelitic lesions, the latter often demanding surgical procedures combined with amphotericin B and ketoconazole. 

Very quickly growing nodules (growth by means of supply with concentrated solutions generated through hot weathering of basalt) have been found in the deep sea. 

Figure 57.2 Iodine deficiency, thyroid enlargement and tumor growth. The starting point for the development of thyroid nodules is hyperplasia induced by iodine deficiency. Iodine deficiency could increase mutagenesis directly (oxidative stress, DNA damage) or indirectly (proliferation and increased number of cell divisions). Subsequently ongoing hyperplasia forms cell clones. Some of them contain somatic mutations leading to cold (white) or hot (black) thyroid nodules.

Thyroid scintigraphy separates hyperfunctioning (hot) and hypofunctional (cold) nodules. Hypofunctioning nodules are much more likely to harbor mafignancy than hyperfunctioning nodules. 

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