Clinical implications of age and excellent response to therapy in patients with high-risk differentiated thyroid carcinoma

Basal or stimulated thyroglobulin in evaluating response to treatment in papillary thyroid carcinoma? A retrospective cohort study

OBJECTIVE

It is not clear whether response to initial treatment in papillary thyroid carcinoma (PTC) patients is best evaluated by measuring thyroglobulin (Tg) in the presence of levothyroxine (BTg) or when stimulated by elevated TSH (STg). The aim of this study was to evaluate whether response to therapy 1 year after initial treatment changes with the use of STg in relation to BTg in PTC patients treated with total thyroidectomy (TT) and radioiodine (131I), and, if observed, to assess which response is better associated with clinical course.

SUBJECTS AND METHODS

This is a retrospective study of 148 PTC patients submitted to TT and 131I. We analyzed the response to therapy (excellent, biochemical incomplete, or indeterminate) at 1 year after initial treatment, using BTg or STg, and compared which method was better associated with "excellent response at final evaluation."

RESULTS

Twenty-eight patients (20.4%) presented change in response to therapy, with 17 of these (60.7%) presenting a worse response. Response using STg was 1.6 times better associated with proposed outcome [odds ratio (OR) = 4.61; confidence interval 95% (IC95%): 2.13-9.98] than with BTg (OR = 2.84; IC95%: 1.33-6.06).

CONCLUSION

Response to therapy at 1 year using STg was altered in approximately 20% of cases and therefore proved to be a better predictor of excellent response in the last evaluation.

Prognostic Factors Improving ATA Risk System and Dynamic Risk Stratification in Low- and Intermediate-Risk DTC Patients

CONTEXT

American Thyroid Association (ATA) guidelines do not consider age at diagnosis as a prognostic factor on the estimation of the risk of persistent/recurrent disease in differentiated thyroid carcinoma (DTC) patients. While age at diagnosis has already been assessed in high-risk patients, it remains to be established in low- and intermediate-risk patients.

OBJECTIVE

The aim of our study was to investigate the role of age as a prognostic factor in the short- and long-term outcome of DTC patients classified at low and intermediate risk according to the ATA stratification risk system.

METHODS

We retrospectively evaluated 863 DTC patients (mean follow-up: 10 ± 6.2 years) 52% classified as low (449/863) and 48% as intermediate risk (414/863). For each ATA-risk class patients were divided into subgroups based on age at diagnosis (<55 or ≥55 years).

RESULTS

In the intermediate-risk group, patients aged 55 years or older had a higher rate of structural disease (11.6% vs 8.9%), recurrent disease (4.1% vs 0.7%), and death (4.1% vs 1%) when compared with younger patients (<55 years) (P = .007). Multivariate analysis confirmed that older age at diagnosis (odds ratio [OR] = 3.9; 95% CI, 1.9-8.6; P < .001) was an independent risk factor for worse long-term outcome together with response to initial therapy (OR = 13.0; 95% CI, 6.3-27.9; P < .001), and T (OR = 32; 95% CI, 1.4-7.1; P = .005) and N category (OR = 2.3; 95% CI, 1.1-5.0; P = .03). Nevertheless, a negative effect of older age was documented only in the subgroup of intermediate DTC patients with persistent structural disease after initial therapy. Indeed, the rate of worse long-term outcome rose from 13.3% in the whole population of intermediate DTC patients to 47.8% in patients with persistent structural disease after initial therapy (P < .001) and to 80% in patients older than 55 years and persistent structural disease after initial therapy (P = .02).

CONCLUSION

Our results suggest that age at diagnosis further predict individual outcomes in Intermediate-Risk DTC allowing ongoing management to be tailored accordingly.

Preoperative voice analysis and survival outcomes in papillary thyroid cancer with recurrent laryngeal nerve invasion

Objective

To investigate the clinicopathological characteristics of papillary thyroid cancer (PTC) and identify risk factors for postoperative recurrence of PTC with recurrent laryngeal nerve (RLN) involvement.

Methods

In total, 171 patients (112 women and 59 men, age: 18-80 years, and 65 patients aged ≥ 55) with T4a PTC with RLN involvement, treated at Beijing Tongren Hospital, Capital Medical University, from January 2006 to December 2020, were retrospectively examined. Clinicopathological characteristics, including voice analysis results, and survival outcomes were assessed. The Mann-Whitney U and Kruskal-Wallis H tests were used to analyze differences in acoustic parameters. The Kaplan-Meier method was used to calculate the overall survival (OS) and recurrence-free (RFS) rates. Univariate and multivariate Cox regression analyses were performed of the clinical data.

Results

The postoperative follow-up period ranged from 12 to 196 months (mean: 66.18 months). Of the 171 patients, 16 had recurrence and 8 died of thyroid-related diseases. The 5-year OS rate was 95.22%. The 5-year RFS rate was 89.38%. Jitter and shimmer were higher and maximum phonation time was shorter in patients with preoperative vocal cord paralysis (VCP) than in those without RLN involvement, and in those with RLN involvement but without preoperative VCP. Acoustic parameters were similar in patients with no preoperative VCP and those without RLN involvement. Voice analysis results did not differ between cases with RLN adhesion and RLN invasion. Univariate analysis showed that age at onset ≥ 55 years, preoperative RLN palsy, and esophageal invasion were risk factors for postoperative recurrence of PTC with RLN involvement. Multivariate analysis showed that onset age ≥ 55 years (OR 4.52, 95% confidence interval: 1.44-14.19, P = 0.010) was an independent risk factor for recurrence.

Conclusions

PTC patients with RLN invasion can achieve good outcomes. Preoperative voice analysis may offer insights into RLN function. Age of onset ≥ 55 years is an independent risk factor for postoperative recurrence in T4a PTC patients.