Israel Medical Association Journal

Background: Due to the high variability in malignancy rate among cytologically indeterminate thyroid nodules (Bethesda categories III–V), the American Thyroid Association recommends that each center define its own categorical cancer risk.

Objectives: To assess cancer risk in patients with cytologically indeterminate thyroid nodules who were operated at our center.

Methods: In a retrospective study, we analyzed the pathology results of all the patients whose fine needle aspiration results showed Bethesda III–V cytology and who subsequently underwent total thyroidectomy or lobectomy from December 2013 to September 2017.

Results: We analyzed 56 patients with indeterminate cytology on fine needle aspiration. Twenty-nine (52%) were defined as Bethesda III, 19 (34%) Bethesda IV, and 8 (14%) Bethesda V category. Malignancy rates were 38%, 58%, and 100% for Bethesda categories III, IV, and V, respectively. Most malignancies in Bethesda categories III and IV were follicular in origin (follicular thyroid carcinoma and follicular type papillary thyroid carcinoma), while 100% of the patients with Bethesda category V were diagnosed with classical papillary thyroid carcinoma. No correlation was found between sonographic and cytological criteria of nodules with Bethesda categories III and IV and rates of malignancy.

Conclusions: We found higher than expected rates of malignancy in indeterminate cytology. This finding reinforces the guidelines of the American Thyroid Association to establish local malignancy rates for thyroid nodules with indetermined cytology.

Background: Patients with systemic sclerosis (SSc) are at increased risk for autoimmune thyroid diseases, but information regarding thyroid nodules and cancer in SSc is scarce.

Objectives: To evaluate the thyroid gland in patients with SSc at a single Israeli center.

Methods: Thyroid workup was conducted in consecutive SSc patients: thyroid-stimulating hormone (TSH), free thyroxine (fT4), anti-thyroid peroxidase, and anti-thyroglobulin antibodies, as well as thyroid ultrasound and fine needle aspiration (FNA) when appropriate.

Results: Fifty patients, mean age 51.3 ± 13.5 years (44 women) were evaluated. Ten were previously diagnosed with thyroid disease. Median TSH level was 2.0 (normal range 0.23–4 mIU/l) and median fT4 level was 1.0 (normal range 0.8–2.0 ng/dL). Among the 40 thyroid disorder-naive patients, 3 had subclinical hypothyroidism and 5 had positive anti-thyroid antibodies; 22 (44%) had 1–6 thyroid nodules, which were ≥ 1 cm in 12 (24%). Accordingly, six patients underwent FNA, and five were diagnosed as colloid nodules and one as papillary carcinoma.

Conclusions: New cases of clinically significant autoimmune thyroid disease were not detected in our cohort of patients with SSc. Nevertheless, almost half had thyroid nodules. The clinical significance of these findings and their relation to thyroid cancer remains to be determined.

Background: More than 90% of all thyroid cancers are differentiated thyroid carcinomas (DTC) with a 10 year survival rate greater than 90%. The commonly used risk stratification systems for DTC include: European Organization for Research and Treatment of Cancer (EORTC), AGES (Age, histologic Grade, Extent of tumor, Size), AMES (Metastasis) and MACIS (Completeness of resection, local Invasion). Other systems are also utilized. Several new factors that may be involved in DTC risk stratification have emerged in recent studies, with other "traditional" factors being challenged. 

Objectives: To present recent updates in the literature on new potential prognostic factors for DTC.

Methods: We conducted a literature review and analysis of publications regarding DTC prognostic factors or risk stratification published in the last 10 years. 

Results: Several new factors with potential prognostic implications for DTC were noted, including family history, lymph node involvement parameters, positive PET-CT findings, multifocal disease, thyroglobulin level and several molecular markers including BRAF. Increasing age is associated with poorer outcome in DTC; however, recent studies suggest that the cutoff point of 45 years may be contested. Furthermore, several studies have shown contradictory results regarding male gender as a negative prognostic factor, thus questioning its prognostic significance. 

Conclusions: A number of new factors with potential prognostic implications for DTC have emerged and should be addressed. However, their role and possible inclusion in new staging systems has yet to be determined.

 

Background: Radiation exposure is a well-known risk factor for well-differentiated thyroid cancer (WDTC). However, disease characteristics, optimal treatment, time from exposure to disease appearance, and the effect on outcome of age at initial exposure have yet to be determined. 

Objectives: To identify the characteristics of radiation-induced thyroid carcinoma.

Methods: We retrieved the charts of all patients previously exposed to radiation who were diagnosed with WDTC between the years 1985 and 2013 in a tertiary referral center. 

Results: Forty-four patients were reviewed. Median time from radiation exposure to diagnosis was 23 years. These patients had higher rates of aerodigestive symptoms and distant metastases on presentation than seen in non-radiated patients. Patients who were exposed to radiation before age 15 years tended to develop the disease at a younger age but had a longer latency period (34.7 ± 15.3 vs. 16.3 ± 10 years, P < 0.001) and none had significantly higher rates of vocal cord palsy, hoarseness on presentation, or aggressive variants on histology compared to patients exposed to radiation at an older age. Disease-specific survival (DSS) was the same for both groups and were similar to that seen in the general population (95% 20 year DSS).

Conclusions: Radiation-induced thyroid cancer has a more aggressive presentation and the age at exposure affects the presentation of disease. Nonetheless, appropriate treatment leads to a favorable prognosis.

 

Objectives: To demonstrate the efficacy of rhTSH in radioiodine thyroid ablation in patients with differentiated thyroid cancer.

Methods: We conducted a retrospective study of patients who underwent total thyroidectomy for well-differentiated thyroid cancer with different levels of risk, treated with rhTSH prior to remnant ablation with radioiodine.  

Results: Seventeen patients with thyroid cancer were studied and followed for a median of 25 months (range 8–49 months). Ablation (defined as stimulated thyroglobulin < 1 mg/ml, negative neck ultrasonography, and radioiodine scan) was successful in 15 patients (88.2%). One of the patients was lost to follow-up.

Conclusions: The use of rhTSH with postoperative radioiodine ablation may be an efficient tool for sufficient thyroid remnant ablation, avoiding hypothyroidal state in the management of thyroid cancer patients.

Background: Heart rate variability is a sensitive marker of cardiac sympathetic activity.

Objectives: To determine whether long-term hyperthyroidism induced by thyroxine suppressive therapy affects HRV[1].

Methods: Nineteen patients treated with suppressive doses of thyroxin for thyroid cancer and 19 age-matched controls were enrolled. Thyroid function tests and 1 minute HRV were performed on all subjects and the results were compared between the groups. The 1 minute HRV was analyzed during deep breathing and defined as the difference in beats/minute between the shortest and the longest heart rate interval measured by eletrocardiographic recording during six cycles of deep breathing.

Results:  One minute HRV during deep breathing was significantly lower among thyroxine-treated patients compared to healthy controls (25.6 ± 10.5 vs. 34.3 ± 12.6 beats/min, P < 0.05). There were no significant differences in mean, maximal and minimal heart rate between the groups

Conclusions: Thyroxine therapy administered for epithelial thyroid cancer resulted in subclinical hyperthyroidism and significantly decreased HRV due to autonomic dysfunction rather than basic elevated heart rate.