Thyroid gland nodular hyperplasia

Thyroid gland nodular hyperplasia
Diagnosis in short
Thyroid FNA compatible with adenomatoid nodule.
Synonyms	nodular hyperplasia, adenomatoid nodule
LM	typically follicles of variable size - may be microfollicular or solid; no nuclear changes of PTC; no fibrous capsule
LM DDx	papillary thyroid carcinoma, follicular thyroid adenoma, follicular thyroid carcinoma
Gross	enlarged thyroid gland +/- distinct nodules
Site	thyroid gland
Signs	thyroid gland enlargement
Prevalence	common
Prognosis	benign
Clin. DDx	malignancy of thyroid gland
Treatment	surgical resection

Thyroid gland nodular hyperplasia is a common thyroid gland pathology and may be an indication for thyroidectomy.

General

• Clinical diagnosis: goitre, AKA sporadic goitre, AKA multinodular goitre (MNG).
• Most common diagnosis in the thyroid.
  • If you've seen a handful of thyroids you've seen this.
• Considered to be a combination of environmental factors (e.g. lack of iodine in the diet) and genetic factors (often with autosomal dominant inheritance).

Gross

Features:

• Enlarge thyroid gland.
• +/-Distinct (well-circumscribed) nodules.

Microscopic

Features:

• Follicles of variable size - key feature.
  • Should be obvious at low power, i.e. with the 2.5x objective.
• +/-Nodules.
  • Do not have a thick fibrous capsule.
  • May have a high cellularity.
  • Architecture: solid or microfollicular.

Negatives:

• No nuclear features suggestive of malignancy (at lower power).
  • One should not look at high power.
• Not cellular.

DDx:

• Papillary thyroid carcinoma - esp. papillary thyroid carcinoma follicular variant.
• Follicular thyroid adenoma - contained in a fibrous capsule.
• Follicular thyroid carcinoma - has fibrous capsule and invasion through it.

Images

• 

  FNA c/w with AN. (WC/Euthman)

• 

  FNA c/w AN. (WC/Euthman)

Molecular

• Nodular hyperplasias may be clonal; however, this is not used for diagnosis and considered clinically irrelevant.

Sign out

HEMITHYROID, RIGHT, HEMITHYROIDECTOMY:
- NODULAR HYPERPLASIA.
- NEGATIVE FOR MALIGNANCY.

HEMITHYROID, RIGHT, HEMITHYROIDECTOMY:
- CELLULAR ADENOMATOID NODULE ON A BACKGROUND OF NODULAR HYPERPLASIA.
- NEGATIVE FOR MALIGNANCY.

RIGHT THYROID, RIGHT HEMITHYROIDECTOMY:
- BENIGN NODULE WITH MICROFOLLICLES IN A BACKGROUND OF NODULAR HYPERPLASIA.
- NEGATIVE FOR MALIGNANCY.

Micro

The sections show thyroid gland with follicles of variable size and marked enlargement. A lymphocytic infiltrate is present. Focal germinal centre formation is present. Oncocytic changes and reactive changes are seen focally. No significant nuclear atypia is identified.

Alternate

The sections show thyroid gland with follicles of variable size and marked enlargement. A large nodule is present with microfollicles that are densely packed around the edge and few in the centre. The nuclei of the microfollicles are round. No significant nuclear membrane irregularities there are apparent. Very rare enlarged nuclei are present. Occasional nucleoli are seen. No nuclear overlap is readily apparent.

See also

• Thyroid gland.
• Thyroid cytopathology.