Lung uptake on I-131 therapy and short-term outcome in patients with lung metastasis from differentiated thyroid cancer

Long-term outcomes and prognostic factors of patients with lung metastases from differentiated thyroid cancer after radioiodine therapy in Japan

Long-term survival in patients with differentiated thyroid cancer (DTC) and lung metastasis remains unexplored in Japan. This study aimed to investigate the long-term survival and prognostic factors of radioiodine therapy (RIT) in a University Hospital setting. This retrospective study included 62 patients with lung metastases from DTC who received RIT between March 2005 and December 2016. According to the ¹³¹I whole-body scan and chest computed tomography results, lung metastases were classified as ¹³¹I-avid or non-¹³¹I-avid, and miliary, micronodular, or macronodular metastases. The 5- and 10-year overall survival (OS) rates from the initial RIT were calculated by the Kaplan-Meier method, and a proportional hazard fit analysis was performed to determine prognostic factors. With a median follow-up of 7.9 years, the 5- and 10-year OS rates from the initial RIT were 93% and 72%, respectively. Univariable and multivariable analyses of patient subgroups revealed that macronodular lung metastases (defined as nodules >1 cm), older age at initial RIT, and high thyroglobulin values (>400 ng/mL) at initial RIT predicted low OS. The 5- and 10-year OS rates of DTC patients with lung metastases were similar to those in previous Japanese reports, which included a smaller sample size compared with ours. Patients with ≤1 cm lung metastases, aged ≤55 years, and a thyroglobulin level of ≤400 ng/mL at the initial RIT had favorable outcomes.

Role of thyroid ultrasound combined with thyroglobulin in the diagnosis of postoperative recurrence of thyroid cancer

BACKGROUND

To study the application value of thyroid ultrasound combined with thyroglobulin (Tg) in the diagnosis of postoperative recurrence of thyroid cancer, so as to provide a reference for clinical practice.

METHODS

Eighty patients with thyroid cancer who underwent operative treatment for more than 2 times in our hospital from January 2014 to December 2016 were selected as the objects of study. After operation, residual thyroid tissues were removed via131Iodine (131I) treatment, the serum Tg and thyroid globulin antibody (TgAb) were detected, and the cervical ultrasound was performed. At 1 week after 131I treatment, the systemic single photon emission computed tomography (SPECT) was performed. Finally, the application values of serum Tg, TgAb and ultrasound in the diagnosis of postoperative recurrence of thyroid cancer were analyzed.

RESULTS

The sensitivity, specificity and accuracy of Tg level in detecting of recurrence and metastasis of differentiated thyroid cancer were 78.5%, 73.3% and 77.5%, respectively, and it was difficult to show whether the postoperative recurrence and metastasis of thyroid cancer occurred through the expression level of serum TgAb. Moreover, TgAb in different concentrations had an effect on the diagnosis of metastasis of differentiated thyroid cancer via Tg. When the TgAb level ≥100 IU/mL, the sensitivity, specificity and accuracy of Tg diagnosis were 51.9%, 50.0% and 51.7%, respectively. When the TgAb level <100 IU/mL, the sensitivity, specificity and accuracy of Tg diagnosis were 94.6%, 71.4% and 88.2%, respectively. Besides, the sensitivity, specificity and accuracy of ultrasonic diagnosis of lymphatic metastasis after the treatment of differentiated thyroid cancer were 78.5%, 60.0% and 75.0%, respectively. The sensitivity, specificity and accuracy of ultrasound combined with Tg in the diagnosis of thyroid cancer were 97.4%, 75.0% and 93.6%, respectively. The difference in the metastasis rate of thyroid cancer was not statistically significant between patients with papillary carcinoma and patients with follicular carcinoma after treatment (P>0.05).

CONCLUSIONS

Thyroid ultrasound combined with Tg is of high clinical value in the diagnosis of postoperative recurrence of thyroid cancer, which can significantly improve the sensitivity, specificity and accuracy of clinical diagnosis. The TgAb level can be detected when Tg is used to monitor the postoperative recurrence and metastasis of thyroid cancer, providing a reference for the clinical prevention and treatment.

Serial stimulated thyroglobulin measurements are more specific for detecting distant metastatic differentiated thyroid cancer before radioiodine therapy

OBJECTIVE

Preablative stimulated thyroglobulin (ps-Tg) has the potential to be used in identifying distant metastatic differentiated thyroid carcinoma (DM-DTC), but its single level can be affected by remnant thyroid tissue and thyrotropin (TSH). The objective of this retrospective study was to evaluate the value of serial ps-Tg measurements in identifying DM-DTC specifically.

METHODS

A total of 317 DTC patients with serial measurements of ps-Tg, TSH and anti-Tg antibody were divided into M1 (n=72) and M0 (n=245) according to the presence of distant metastasis (DM) or not. The initial ps-Tg measurement, with a corresponding TSH exceeding 30 μIU/mL, was marked as Tg1, and ps-Tg measured right before radioactive iodine (RAI) therapy was defined as Tg2, with a median interval of 8 days. ΔTg denotes Tg2-Tg1, and ΔTSH denotes TSH2-TSH1. Tg1, Tg2, ΔTg, and ΔTg/ΔTSH were tested for efficacy in identifying DM-DTC using receiver operating characteristic (ROC) curve analysis, and further compared with chest computed tomography (CT) and posttreatment whole-body RAI scan (RxWBS).

RESULTS

Compared with single ps-Tg measurement (Tg1 or Tg2), both ΔTg and ΔTg/ΔTSH were more narrowly distributed around zero in the M0 group, which made their distribution in the M1 group more distinguished in a relatively dispersed way. ΔTg/ΔTSH manifested a higher accuracy (88.64%) and specificity (90.20%) in identifying DM-DTC than Tg1 or Tg2 measurements, with a much higher specificity than chest CT (90.20% vs. 66.00%) and a much higher sensitivity than RxWBS (83.33% vs. 61.11%).

CONCLUSIONS

Serial ps-Tg measurements even over as short an interval as 8 days hold incremental value in identifying DM-DTC. ΔTg/ΔTSH is a specific early biochemical marker for DM-DTC.

Clinical management and outcomes in patients with hyperfunctioning distant metastases from differentiated thyroid cancer after total thyroidectomy and radioactive iodine therapy

BACKGROUND

Hyperfunctioning distant metastasis (HFDM) from differentiated thyroid cancer (DTC) is a rare entity. This study aimed to assess the outcomes of DTC patients presenting with HFDM after total thyroidectomy and radioactive iodine therapy.

METHODS

A total of 5367 DTC patients treated with (131)I after total thyroidectomy were analyzed retrospectively from January 1991 to June 2013. Therapeutic efficacy was evaluated based on changes in serum thyroglobulin (Tg) and anatomical imaging changes in metastatic lesions. The relationships between survival time and several variables were assessed by univariate and multivariate analyses using the Kaplan-Meier method and Cox's proportional hazards model respectively.

RESULTS

Thirty-eight patients with HFDM from DTC were diagnosed, including four with hyperthyroidism, four with subclinical hyperthyroidism, and three with subclinical hypothyroidism. The remaining 27 were euthyroid. Of 25 patients with lung metastases, 84% (21/25) showed disappearance or shrinkage of lung nodules; of 24 patients with bone metastases, 66.67% (16/24) exhibited no obvious imaging changes in metastatic bone lesions after (131)I therapy. Serum Tg decreased significantly in 81.58% (31/38) and increased in 18.42% (7/38) after (131)I therapy. The 10-year survival rate of DTC patients with HFDM was 65.79% (25/38). Multivariate analyses identified age at occurrence of distant metastases (<45 years), only lung metastases, and papillary thyroid cancer (PTC; p=0.032, NA, and 0.043) as independent predictors of survival.

CONCLUSION

The response of hyperfunctioning lung metastases to (131)I treatment was better than that of non-hyperfunctioning lung metastases in DTC, while hyperfunctioning bone metastases responded similarly compared to non-hyperfunctioning bone metastases. Patients younger than 45 years at occurrence of distant metastases, those with only lung metastases, and patients with PTC had better prognoses.