Page 558 - Concise Pathology for Exam Preparation ( PDFDrive )

20 Endocrinology 543

Colloid-filled
follicles of
variable size

Foamy histiocytes
with haemosiderin

FIGURE 20.2. High power view of a nodule showing follicles of varying size lined by flat to
cuboidal epithelium. There is a focus of haemorrhage with aggregates of haemosiderin-laden
macrophages (H&E; 100X).

Cut surface:
• Irregular nodules showing a variable amount of brown gelatinous colloid.
• Regressive changes like haemorrhage, calcification, fibrosis and cystic change.
Microscopy (Fig 20.2):
• The nodules consist of colloid-filled follicles of varying size lined by flat to cuboidal
epithelium. The colloid-filled follicles may fuse to form large colloid-filled cysts.
• In the background of an enlarged multinodular thyroid, a solitary dominant or hyper-
plastic nodule may show follicular hyperplasia and hypertrophy (called nodular
adenomatous goitre).
• Adenomatous goitre can be confused with a follicular adenoma; however, the latter
shows a prominent capsule which is lacking in an adenomatous nodule.
Clinical features
• Patients are usually euthyroid and present with an asymptomatic mass in the neck.
Some patients may have subclinical hyperthyroidism and decreased TSH levels and
others may develop frank hyperthyroidism or toxic multinodular goitre (Plummer
syndrome).
• Main symptoms due to mass effects (airway obstruction due to compression of trachea;
dysphagia due to compression of the oesophagus; venous congestion of the head due to
compression of superior vena cava and hoarseness due to recurrent laryngeal nerve
compression).

Q. Enumerate the salient features of a solitary nodule of thyroid.

Ans. A solitary thyroid nodule is a palpable discrete swelling within an otherwise normal
thyroid gland.
• It is more likely to be malignant than multiple nodules.
• Nodules in younger patients and males are more often malignant than nodules in older
patients and females.
• Nodules that do not take up radioactive iodine (cold nodules) are more likely to be
malignant.
• Nodules that take up radioactive iodine (hot nodules) are more likely to be benign,
eg, nodular (adenomatous) goitre, thyroiditis and simple cysts.

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