Associations of telomerase reverse transcriptase rs10069690 and rs2736100 polymorphisms with papillary thyroid carcinoma

Papillary thyroid carcinoma is one of the most common endocrine malignancies. Telomerase reverse transcriptase rs10069690 and rs2736100 polymorphisms have been studied in thyroid carcinomas with different ethnicity, but the results were inconsistent. Therefore, we evaluated the relationship between rs10069690 and rs2736100 polymorphisms and papillary thyroid carcinoma risk and furtherly investigated the associations of these polymorphisms with stimulated thyroglobulin (sTg) positivity and adverse reactions of I treatment in papillary thyroid carcinoma. Four hundred thirty-six papillary thyroid carcinoma patients and 345 controls of Chinese Han population were included in our study. Rs10069690 and rs2736100 were genotyped using improved multiple ligase detection reactions. Analysis of inheritance model was performed using the unconditional logistic regression. In our study, rs10069690 and rs2736100 were associated with papillary thyroid carcinoma risk, especially in females over 45 years of age (P = 0.002 and P = 0.032, respectively). Rs10069690 was associated with sTg positivity and with an rs10069690-related occurrence risk order of thyroglobulin antibody (Tg-Ab)(+) + Tg(+) > Tg-Ab(+) + sTg(-) > Tg-Ab(-) + sTg(+). Patients with the homozygous TT genotype of rs10069690 had an increased risk of neck discomfort (P = 0.033), while the homozygous CC genotype of rs2736100 had a decreased risk of gastrointestinal toxicity (P = 0.048). Our data demonstrated that rs10069690 and rs2736100 might be bio-indicators related to papillary thyroid carcinoma risk in females over 45 years of age and I treatment-related toxicity. In addition, rs10069690 may be a predictor of bad clinicopathological features and poor prognosis from a serological point of view.

Prognostic value of star-shaped intense uptake of 131I in thyroid cancer patients

OBJECTIVE

After ¹³¹I treatment in patients with differentiated thyroid carcinoma (DTC), we sometimes find a star-shaped intense uptake of ¹³¹I on therapeutic whole body scans (Rx-WBS), called star artifacts. Therefore, we analyzed the relevant clinical factors and prognostic value of star artifacts in DTC patients.

METHODS

809 DTC patients who received ¹³¹I treatment were retrospectively evaluated and divided into 2 groups of patients with and without star artifacts. We evaluated the therapeutic response which was divided into excellent response (ER), biochemical incomplete response (BIR), indeterminate response (IR), and structural incomplete response (SIR). Clinical factors for the presence of star artifacts were analyzed. We also compared the rate of ER, BIR, IR, SIR and recurrence rate between group 1 and group 2.

RESULTS

The major clinical factors included stimulated thyroglobulin (sTg)>1.8ng/ml, 24h radioiodine uptake (RAIU)>2.2%, and positive ^99mTcO4^- thyroid imaging for the presence of star artifacts. In patients with sTg levels>10ng/ml, patients in group 1 had a higher rate of ablation success and ER than patients in group 2 (80.2% vs 65.6%, P=0.038, 31.6% vs 13.1%, P=0.008, respectively) and had a similar rate of BIR, IR, SIR. Recurrence rate was similar between group 1 and group 2 (5.2% vs 3.1%, P=0.13).

CONCLUSION

More remnant thyroid tissue is one of the factors associated with the presence of star artifacts on Rx-WBS. Patients with star artifacts exhibit a better therapeutic response (ER) when sTg levels are >10ng/ml. However, star artifacts have no effect on the recurrence rate.

The predictive value for excellent response to initial therapy in differentiated thyroid cancer: preablation-stimulated thyroglobulin better than the TNM stage

PURPOSE

This study aimed to identify the predictive value of the low preablation-stimulated thyroglobulin (ps-Tg, <2 ng/ml) for excellent response to radioiodine remnant ablation in differentiated thyroid carcinoma.

PATIENTS AND METHODS

A total of 398 consecutive patients who underwent total thyroidectomy and radioactive iodine remnant ablation therapy were reviewed retrospectively. Each patient was risk-stratified using the American Joint Cancer Committee and risk staging systems and using response to the initial therapy reclassification system. ps-Tg was defined as less than 2 ng/ml with negative thyroglobulin antibody under thyroid-stimulating hormone stimulation. A multivariate analysis was carried out for ps-Tg, TNM stage, and other potential clinical and pathologic factors.

RESULTS

We followed the patients for a median of 32.7 months. Overall, an excellent rate of response was achieved in 367 (92.2%) of the 398 patients. The only variable found to be associated with excellent response was ps-Tg (odds ratio=2.530, P=0.009) by multivariate analysis. The subgroups with 0<ps-Tg<1 ng/ml had a higher success ablation rate than the patients with 1≤ps-Tg<2 ng/ml. Overall, 31 patients were not achieving an excellent response, and most of them showed an indeterminate response. Only two patients who achieved an excellent response were confirmed to have developed recurrence in the follow-up, both in the local regional lymph nodes.

CONCLUSION

There is a good probability that most low ps-Tg (<2 ng/ml) patients can achieve an excellent response. ps-Tg is the essential and independent predictor for an excellent response in the patients with ps-Tg less than 2 ng/ml, which is better than TNM stage.

Is Very High Thyroid Stimulating Hormone Level Required in Differentiated Thyroid Cancer for Ablation Success?

Objective:

Remnant ablation with radioactive iodine (I-131) is a successful form of treatment that aims to destroy the remaining residual tissue and/or metastatic tissue after total thyroidectomy in differentiated thyroid cancer (DTC) patients. High level of thyroid stimulating hormone (TSH) (≥30 mIU/L) is recommended for success of ablation treatment. In this retrospective study, our aim was to investigate whether the TSH levels at the time of ablation effect the success of radioactive iodine remnant ablation.

Methods:

Patients who were diagnosed with DTC, treated with bilateral total/near total thyroidectomy and who were referred for I-131 remnant ablation were included in this study. Patients with undetectable TSH-stimulated serum thyroglobulin (Tg) level, normal physical examination, negative results on whole body scan with I-131, and no evidence of neck lymph node metastasis on ultrasound were defined as disease-free. The correlation between TSH level at the time of ablation and ablation success was assessed.

Results:

Two hundred sixty one consecutive patients were included in the present study. Mean TSH level was 19.47±6 mIU/L in the 34 patients with TSH <30 mIU/L, while mean TSH level was 73.65±27 mIU/L in the 227 patients with TSH ≥30 mIU/L during I-131 remnant ablation. Ablation was unsuccessful in only one patient with TSH <30 mIU/L who had lung metastasis. Ablation was unsuccessful in 5.1% of patients with TSH ≥30 mIU/L. The effect of TSH level was not significant on ablation success (p=0.472).

Conclusion:

In conclusion, we think that a high TSH serum level alone is not a factor for the success of ablation. Age, presence of metastasis, extent of residual thyroid mass should also be considered. Especially, in the presence of metastatic tissue, obtaining adequate increase in TSH level is not always possible. The success of ablation at lower levels of TSH elevations may be sufficient for patients, and long-term hypothyroidism may not be required.