Postintervention serum TSH levels may be useful to differentiate patients who should undergo levothyroxine suppressive therapy after thyroid surgery for multinodular goiter in a region with moderate iodine deficiency

Hemithyroidectomy for benign euthyroid asymmetric nodular goitre

BACKGROUND

There is no consensus on the optimal surgery extent for patients with benign euthyroid asymmetric nodular goitre (AMNG).

METHODS

We reviewed medical literature using the PubMed engine to address the following issues: definition and prevalence, rationale for hemithyroidectomy, long-term outcomes, follow-up, revision surgery and image-guided thermal ablation of contralateral benign thyroid nodules following hemithyroidectomy for AMNG.

RESULTS

In total, 102 articles were found in MEDLINE using a keyword search strategy; subsequently, we selected 36 articles with clinical pertinence.

CONCLUSIONS

AMNG is a common clinical and surgical problem. Depending on the extent of the disease and individual surgeon preferences, either unilateral or bilateral thyroidectomy can be performed. Hemithyroidecomy can be considered for some patients with AMNG and the low risk of recurrent disease as a safer alternative to total thyroidectomy but it requires life-long follow-up, is associated with a higher recurrence risk and a need for revision thyroidectomy in selected subjects.

Levothyroxine therapy in preventing nodular recurrence after hemithyroidectomy: a retrospective study

AIM

To determine the effect of levothyroxine (L-T4) therapy on the recurrence rate of nodular disease in patients previously treated with lobectomy for benign nodular goiter.

METHODS

Two hundred and thirty-tree patients (38 males, 195 females; age 49.9+/-13.1 yr) with no post-surgical evidence of nodular disease in the remnant, were followed- up yearly with serum TSH and ultrasound (US). Nodular recurrence was defined as a lesion of at least 5 mm at US. Patients were divided in 2 groups based on whether or not they had been treated with L-T4 after surgery: Group 1 (45 patients) who did not receive any L-T4, and Group 2 (188 patients) treated with L-T4. Group 2 was further subdivided in Group 2a (123 patients) receiving L-T4 substitutive therapy (TSH>or=0.5 and <or=3 mUI/l) and Group 2b (65 patients) receiving L-T4 at TSH-suppressive dose (TSH<0.5 mUI/l).

RESULTS

Mean observation period was 5.8+/-4.7 yr. Overall, 71 out of 233 (30.5%) patients experienced recurrence of thyroid nodular disease: 29 patients (64.4%) in Group 1, 24 (19.5%) patients in Group 2a, and 18 (27.7%) patients in Group 2b. The recurrence rate was significantly lower (p<0.001) in Group 2 compared with Group 1, but no significant difference was observed between Groups 2a and 2b.

CONCLUSION

In patients who have undergone hemithyroidectomy for benign monolobar nodular disease, L-T4 therapy may prevent recurrence of nodular disease. TSH suppression may not be required for prevention of recurrence in the remnant thyroid tissue.

Tear function and ocular surface changes in multinodular goiter patients

AIMS

To evaluate preoperative and postoperative conjunctival surface changes in multinodular goiter (MNG) patients and to compare their results with healthy control subjects.

METHODS

Twenty MNG patients who had undergone near total thyroidectomy were evaluated pre- and postoperatively at the end of the 3rd month and the 1st year by performing tear function tests and conjunctival impression cytologic analysis. These results were compared with the results of 15 healthy volunteers.

RESULTS

When preoperative and postoperative tear function parameters were compared, the mean Schirmer test value and BUT value were decreased, the mean Rose Bengal staining score was increased during the postoperative period. These differences were statistically significant at the end of the 1st year (p < 0.001). The average goblet cell density of the MNG patients decreased significantly during the postoperative period when compared with the preoperative values (p < 0.001). All these findings of the MNG cases were significantly different from the results of the control group both before and after the operation.

CONCLUSION

Tear function tests and the impression cytology findings of the MNG cases were statistically different from the results of the control group during the pre- and postoperative period. We recommend postoperative follow-up of these patients for ocular surface changes.

[Surgical resection of the thyroid and parathyroid glands]

The main indication for surgery of the thyroid gland is the resection of nodular, suspicious or hyperfunctioning tissue. Following thyroidectomy, L-thyroxine therapy is initiated adjusted to the remnant thyroid function. To prevent recurrence of a multinodular goiter, supplementation with iodine is strongly recommended. The management of patients with differentiated thyroid cancer depends on risk stratification. Although large prospective studies are missing, low-risk patients probably do not benefit from total thyroid ablation and lifelong thyroxine suppression therapy. As a result of impaired parathyroid function or resection of the parathyroid glands for hyperparathyroidism, acute or chronic hypocalcaemia can develop. If treatment with oral calcium is insufficient, the addition of a vitamin D analogue is necessary. This requires close monitoring to avoid renal or other hypercalcaemic complications.

Grey-scale analysis allows a quantitative evaluation of thyroid echogenicity in the patients with Hashimoto's thyroiditis

OBJECTIVE

In the present study we have performed a grey-scale quantitative analysis of thyroid echogenicity in the patients affected by Hashimoto's thyroiditis (HT), obtaining a numerical estimate of the degree of hypoechogenicity associated with the appearance of thyroid dysfunction.

MATERIALS AND METHODS

The study group included 89 patients with serum positivity for thyroglobulin (TgAb) and/or peroxidase (TPOAb) antibodies. Ultrasound (US) evaluation of thyroid gland and biochemical assay of serum thyrotropin (TSH), free-thyroxine (FT4) and free-triiodiothyronyne (FT3) were performed in all patients, and in 40 healthy subjects enrolled as control group. Thyroid echogenicity was compared with that of the surrounding neck muscles, using the grey-scale histogram analysis. The echogenicity was expressed in grey-scales (GWE).

RESULTS

In HT patients, the mean of thyroid echogenicity was lower when compared to the normal thyroid (61.9 +/- 8.3 GWE vs. 71.9 +/- 3.1 GWE; P = 0.01). In all HT patients the lowest limit of thyroid echo distribution was in the echogenicity range of the surrounding muscle, the overlapping ranging between 3.4% and 95.0% (mean +/- SD 48.4 +/- 20.9%). The extension of like-muscle hypoechogenicity into the thyroid gland was significantly correlated with serum TSH values (r = 0.37; P < 0.001), serum FT4 values (r = -0.60; P < 0.001), and serum TPOAb values (r = 0.31; P = 0.004). Nobody was hypothyroid when the hypoechogenicity was less than 38.0%, whereas hypothyroidism occurred in all cases with hypoechogenicity of more than 68.9%. The receiving operating characteristic curve demonstrated that 48.3% was the best cut-off for identifying hypothyroid patients with sensitivity, specificity and diagnostic accuracy of 88.9%, 86.3% and 87.6%, respectively.

CONCLUSIONS

In conclusion, the grey-scale quantitative analysis has provided a measure of thyroid hypoechogenicity associated with the appearance of hypothyroidism during the course of HT. The results of the present study would encourage the application of the computerized grey-scale analysis as complementary tool to US evaluation in the patients affected by HT.

Fine needle aspiration cytology in non-neoplastic non-toxic recurrent nodular goitre

The aim of the study was to examine whether evaluation of anisokaryosis is helpful in the cytological diagnosis of focal lesions in non-toxic recurrent goitre (NRG) after thyroidectomy for non-malignant goitre. Karyometric analysis was performed in routine cytological smears obtained from 80 females: 40 with focal lesions in non-toxic primary goitre (NPG) and 40 with NRG (postoperative histopathological examination revealed nodular goitre in both groups in all cases). We found that the level of anisokaryosis was significantly (P<0.005) higher in NRG than in NPG. There were no significant differences between the two lesions, in cellular composition or thyroid follicular cell arrangement. Thus, isolated anisokaryosis, a feature of malignancy in patients without a prior thyroidectomy, has limited diagnostic value in recurrent goitre.

Multinodular goiter

MNG is a common clinical problem. Though most goiters are benign and asymptomatic, they may cause concern when they create compressive symptoms, develop autonomous functioning nodules, or form suspicious nodules. Diagnostic evaluation should include clinical evaluation, laboratory tests including TSH, and consideration of additional evaluation and imaging when there exists suspicion of complicating factors or risk of malignancy. In nontoxic MNG, suppression therapy or serial clinical exams and TSH values are appropriate in an asymptomatic, nonsuspicious goiter. In toxic MNG, treatment of the resulting thyrotoxicosis followed by RAI or surgery is indicated. When compressive symptoms, risk of malignancy, or cosmetic deformity develops, surgery also may be indicated.

Iodized salt improves the effectiveness of L-thyroxine therapy after surgery for nontoxic goitre: a prospective and randomized study

OBJECTIVE

To investigate whether the addition of iodized salt to daily diet in thyroidectomized patients for nontoxic goitre could influence the effectiveness of nonsuppressive L-thyroxine (L-T4) therapy on thyroid remnant size, during 12 months' follow-up after thyroid surgery.

DESIGN AND PATIENTS

A consecutive series of selected 139 patients (26 males, 113 females; median age 45 years, range 30-69 years) living in a moderate iodine-deficient area, and undergoing thyroid surgery for nontoxic multinodular goitre, was enrolled. Patients were assigned randomly to two different therapeutic regimens: 70 patients received L-T4 therapy alone (Gr. L-T4), while the remaining 69 patients took iodized salt on a daily basis in addition to L-T4 treatment (Gr. L-T4 + I). In both groups, the initial L-T4 dose was 1.5 microg/kg/day, which, in our experience, has been shown to be intermediate between suppressive and replacement doses. To avoid the risks of mild thyrotoxicosis and to limit the excessive TSH stimulation of the thyroid remnant, the L-T4 dose was adjusted in those patients with serum TSH levels outside the lowest two-thirds of the normal range (0.3-2.5 mU/l). An ultrasound evaluation of thyroid remnant size was performed after thyroid surgery and 12 months later.

RESULTS

After surgery, the median thyroid remnant volume was 3.5 ml (range 0.4-13.9 ml) in Gr. L-T4 and 4.6 ml (range 0.5-12.7 ml) in Gr. L-T4 + I (P = 0.06). After 1 year of follow-up, the patients treated with L-T4 + I obtained a remnant volume reduction (-39.7%, range -87.0% to +91.2%) significantly (P = 0.006) greater than that observed in patients assuming L-T4 alone (-10.2%, range -89.4% to +85.0%). However, the percentage of patients showing an increase in remnant size in the months following surgery was higher in Gr. L-T4 than in Gr. L-T4 + I (22/60 vs. 9/66; P = 0.01). In Gr. L-T4 patients the thyroid remnant volume variation throughout 12 months of treatment was correlated significantly with the size of the thyroid remnant found at the first ultrasound evaluation (R(2) = 0.3; P < 0.001). No such correlation was found in Gr. L-T4 + I patients, for whom the therapy maintains a similar effectiveness in patients with either a large or a small postsurgery thyroid remnant. In patients treated with L-T4 alone, the remnant volume variation was correlated significantly with the median serum TSH values attained in the course of treatment (R2 = 0.4; P < 0.001). The highest reduction in remnant volume was observed only by lowering the serum TSH concentrations. In patients treated with L-T4 plus iodine, instead, the thyroid remnant volume reduction occurred independently of the plasma TSH levels attained in the course of treatment.

CONCLUSIONS

Our short-term prospective and randomized study leads us to conclude that, in patients living in a moderate iodine-deficient area and undergoing thyroid surgery for nontoxic goitre: (1) the iodine prophylaxis improves the effects of postsurgery nonsuppressive L-T4 therapy on thyroid remnant size. (2) In patients treated with L-T4 alone the therapeutic effectiveness decreases in the presence of a large postsurgery thyroid remnant. With the addition of iodine, the L-T4 maintains a similar efficacy in patients with either a large or a small remnant. (3) During treatment with L-T4 alone the highest therapeutic effectiveness is attained by lowering the plasma TSH concentration. With the addition of iodized salt to the daily diet the effects of L-T4 on remnant size are relevant independently of the TSH levels.

Eight parathyroid glands incidentally discovered during a surgical intervention for secondary hyperparathyroidism: an unusual clinical finding

Here we describe the uncommon case of a Caucasian male with secondary hyperparathyroidism due to 8 parathyroid glands discovered in the course of a surgical exploration. The patient (age 49 yr) with a 21-yr history of chronic renal failure came to our observation in June 1999 complaining of depression, muscle weakness, bone and joint pain, movement hindrance. The biochemical evaluation evidenced low-normal serum calcium, high phosphorus and PTH levels. The symptoms and the biochemical findings were suggestive for secondary hyperparathyroidism. The neck US revealed an increase of thyroid gland volume with diffuse hyperechogenity; two nodules of 20 and 25 mm as maximum diameter were found in the thyroid parenchyma, while 4 hypoechogenous nodules (maximum diameter ranging from 13.0 to 30.0 mm) with clean borders and anechogenous areas inside were evidenced in the rear side of the thyroid lobes. The parathyroid scan with 99mTc and 201 Tl demonstrated increased uptake bilaterally in the inferior side of the neck. The patient underwent a total parathyroidectomy with near total thyroidectomy in November 1999. Histological examination of surgical specimen evidenced 6 hyperplastic parathyroid glands in back side of the 2 lobes (3 on the right and 3 on the left), and the examination of the thyroid gland showed 2 hyperplastic parathyroids (5 mm and 15 mm maximum diameter) into the 2 nodules previously evidenced by US. The physiopathological and clinical and therapeutic implications of this observation are discussed.

The influence of parity on multinodular goiter prevalence in areas with moderate iodine deficiency

Despite the observation that parity may increase the risk of thyroid carcinoma, very few studies have investigated the possible repercussion of parity on thyroid benign pathology. Recently, parity has been identified as one of the factors contributing to a larger thyroid size in healthy females. The aim of this work was to investigate a possible role for parity on the prevalence of multinodular goiter in iodine deficient areas. For this purpose, the reproductive histories of 2 cohorts of women, normal (Group I, 235 cases) and non-toxic multinodular goiter (NTMNG) affected (Group II, 274 cases) were compared. All subjects were euthyroid and had no previous history of thyroid function abnormalities. The number of full-term previous pregnancies (2.55+/-0.11 vs 1.77+/-0.10) and age (47.7+/-0.76 vs 42.3+/-0.83 yr) were found significantly higher (p<0.001) in multinodular goiter (MNG) patients than controls. Parity and age were found to be directly correlated (p<0.001), nevertheless the partial correlation coefficients demonstrated an independent and statistically significant difference for both variables between normal and NTMNG. Therefore, the independent effects of parity and age were further investigated. The effect of age on NTMNG prevalence seems to be weaker, in fact significant differences (p<0.001) for age between patients and controls were detected only when the effect of parity was absent (nulliparous), while with increasing gestations the effect of age disappeared. Our results indicate that age plays a minor role compared to parity which can therefore be considered as a stronger risk factor. In conclusion, the present study shows that, at least in iodine deficient regions, non-toxic multinodular goiter women show a statistically significant higher parity rate than healthy controls. Age may play a certain role but only when additional stronger risk factors are absent.