Long‐Term Observation of Serum Thyroglobulin after Resection of Nontoxic Goiter and Relation to Ultrasonographically Demonstrated Relapse

Abstract

The object was to carry out a prospective study of the changes in serum thyroid hormones and thyroglobulin (Tg) following resection of nontoxic goiter and to investigate if there was a correlation to the pattern of relapse. A group of 39 consecutive patients, mainly with nodular, nontoxic goiter, were studied for 13 years following thyroidectomy. No thyroid hormone replacement therapy was given after surgery. The preoperative serum Tg level was elevated. After operation the mean serum Tg declined to a nadir of 43 micrograms/L at 1 year and subsequently increased to 90 micrograms/L at 10 years, with large individual differences. In 19 patients the serum Tg increased, in 1 it decreased, and in 19 no significant alteration was observed. Serum free thyroxine and triiodothyronine indices decreased following resection but achieved normal levels within 6 to 12 months. Serum thyroid-stimulating hormone increased after resection, with a peak level 1 month after surgery, but it returned to normal levels at 1 year and remained stable for the rest of the period. At 13 years after resection the thyroid volume was determined by ultrasonography in 30 of the patients. In 10 patients the thyroid volume was enlarged (>/= 28 ml). In this group a rise of average serum Tg after resection [DeltaTg(10-1 year)] of 133 micrograms/L was observed, compared to 26 micrograms/L in the 20 patients without sonographic relapse (volume < 28 ml). A positive correlation was demonstrated between serum DeltaTg(10-1 year) postsurgically and thyroid volume 13 years after surgery. However, an overlap was observed between the groups with and without ultrasonographic relapse, probably in part due to large differences in the Tg synthesis activity of different follicle cell clones. It is concluded that repeated serum Tg determinations may provide biochemical evidence of increased growth activity of thyroid remnants monitored after goiter resection.

American Association Of Clinical Endocrinologists, Associazione Medici Endocrinologi, And European Thyroid Association Medical Guidelines For Clinical Practice For The Diagnosis And Management Of Thyroid Nodules

“…Assessment of serum thyroglobulin is not recommended in the diagnosis of thyroid nodules (84). In patients undergoing surgery for malignancy, testing of serum thyroglobulin may be considered so as not to overlook a false-negative serum thyroglobulin value due to decreased thyroglobulin immunoreactivity or heterophilic antibodies (85).…”

Serum Tg—A Sensitive Marker of Thyroid Abnormalities and Iodine Deficiency in Epidemiological Studies

“…The value in the diagnosis of other thyroid diseases is limited, because serum Tg is increased in almost all kinds of thyroid disease with an overlap to healthy individuals. Still, some clinical applications of serum Tg measurements have been suggested, as for instance in the diagnosis of subacute thyroiditis (3), thyrotoxicosis factitia (4,5), or as a marker of postoperative recurrence of nontoxic goitre (6). Serum Tg levels may predict the outcome of antithyroid drug therapy in Graves' disease (7)(8)(9), whereas the ability of serum Tg measurements to predict the outcome of thyroid hormone treatment of nontoxic goitre has not been convincing (10,11).…”

What Constitutes Adequate Surgical Therapy For Benign Nodular Goiter?

“…Recurrent disease has been reported in the literature to occur as early as 6 mo, but it is usually not diagnosed until 4 or more y after surgery depending on the frequency and type of surveillance methods used [15][16][17]. Patients in this study developed recurrence at a median of 8 y with 55.8% of recurrences noted by physical examination and 43.2% of recurrences detected by follow-up imaging, either cervical ultrasound or computed tomography.…”