Opposite nodule

absent

Opposite nodule

present

Euthyroid

Hypothyroid

Scenario I

Yes

 

Yes

 

Scenario II

Yes

 

 

Yes

Scenario III

 

Yes

Yes

 

Scenario IV

 

Yes

 

Yes

 

Scenario I.  The patient has a nodule on the affected side, but the opposite gland is normal.  The patient also has normal pre-op thyroid function.

  • Pre-op size of nodule – if greater than 1 cm then a cancer diagnosis will require completion thyroidectomy.
  • Pre-op risk of malignancy – how suspicious is this nodule. Several factors can risk-stratify a nodule, including size, ultrasound features (micro-calcification, etc.), FNA results, family history and others.
  • In most cases, I recommend partial thyroidectomy in this scenario, as we like to avoid creating the permanent need for thyroid hormone pills. Given the normal opposite side, there is a good chance of avoiding the need for supplementation.

Scenario II.  The patient ‘s opposite gland is normal, but he/she is hypothyroid and already taking thyroid hormone supplementation.

  • Pre-op size of nodule – if greater than 1 cm then a cancer diagnosis will require complete thyroidectomy.
  • Pre-op risk of malignancy – how suspicious is this nodule. Several factors can risk-stratify a nodule, including size, ultrasound features (micro-calcification, etc.), FNA results, family history and others.
  • This scenario is a borderline case. Pro and con arguments exist for total thyroidectomy.
    • Pro total thyroidectomy: In the event of cancer, no further surgery will be necessary; we avoid the potential for completion thyroidectomy in the event of cancer and also avoid any risk of the opposite normal gland developing a worrisome nodule years later.  Thyroid hormone levels may be easier to control with the entire gland removed.
    • Con total thyroidectomy. Total thyroidectomy does incur risk of hypocalcemia, which can be severe or in very rare cases permanent; partial thyroidectomy avoids this.  If the nodule is benign, there would be no risk of hypocalcemia.  Total thyroidectomy requires a one-night stay in the hospital.
  • In Scenario II, we discuss the pros and cons with the patient. This decision is made by the patient with advice from the surgeon.  Ultimately, many factors will go into this decision; it should be made with full education.

Scenario III.  The patient has one or more nodules on the opposite side of the thyroid gland and has normal thyroid function.  He/she does not take thyroid hormone pills pre-operatively.

  • When opposite side nodules are present, decisions become more complex. For  large opposite nodules or when there is a strong suspicion for cancer > 1cm on the primary side of concern, we are more likely to recommend total thyroidectomy.
    • Pro total thyroidectomy: The opposite nodules will very likely have to be removed if the first side shows cancer of any size.  Even if the first side is benign, there is no guarantee that the opposite side will not grow or develop suspicious features in the future, requiring additional surgery.  Depending on the size and character of the opposite nodules, long-term monitoring with ultrasound +/- needle biopsied may be necessary.
    • Pro partial thyroidectomy: We want to avoid creating permanent need for thyroid hormone replacement for benign nodules.

Scenario IV.  The patient has one or more nodules on the opposite side of the thyroid gland and is hypothyroid. He/she is already taking a thyroid hormone supplement.

  • When the opposite gland has nodules and the patient is already taking thyroid hormone replacement, there is a stronger argument for total thyroidectomy, depending on the size of all of the nodules involved and the degree of concern for malignancy in the suspicious nodule.
    • Pro total thyroidectomy: The gland is non-functional and represents a source of risk for repeat thyroid surgery in the event of a cancer diagnosis or future suspicious change on the remaining opposite side. Long-term monitoring of the opposite side is likely to be necessary.
    • Pro partial thyroidectomy: An overnight hospital stay can be avoided  with partial thyroid surgery.  For low risk nodules to be removed and small contra-lateral thyroid nodules without compression symptoms, less surgery is reasonable.  Partial thyroid surgery avoids risks of hypocalcemia.