The impact of completion thyroidectomy followed by radioactive iodine ablation for patients with lymph node recurrence of papillary thyroid carcinoma

Utility of adjuvant radioactive iodine therapy after reoperation in papillary thyroid carcinoma with cervical lymph node recurrence

PURPOSE

The aim of this study was to evaluate the utility of RAI therapy after reoperation for patients with LN relapse.

MATERIALS AND METHODS

We retrospectively evaluated PTC patients who had undergone reoperation due to cervical LN recurrence. We used the chi-square test, Fisher's exact test, Student's t test and the Mann-Whitney U test to compare characteristics between patients retreated with RAI and those who did not receive RAI after reoperation. A multivariate logistic regression model was used to determine the association between RAI and biochemical response. By means of the Kaplan-Meier estimator and a multivariate Cox proportional hazard model, we assessed whether administration of RAI after reoperation is associated with improved prognosis.

RESULTS

RAI therapy was closely associated with a superior biochemical response in all selected patients according to both univariate (p = 0.012) and multivariate analyses (p = 0.020). Thirteen of 97 patients developed a second recurrence or progression of structural disease during follow-up. A Kaplan-Meier progression-free survival (PFS) curve showed that high post-retreatment thyroglobulin (Tg) levels (≥ 1 ng/mL) were associated with unfavourable prognosis (p = 0.0172). In the subgroup analysis, univariate analysis revealed that only patients without extranodal invasion who received adjuvant RAI therapy achieved better PFS than those who did not receive RAI therapy (p = 0.0203). Multivariate analysis showed that RAI (p = 0.045) also improved PFS in patients without extranodal invasion.

CONCLUSIONS

Adjuvant RAI after reoperation for PTC recurrence/persistence was associated with a favourable biochemical response and tended to increase PFS. Specifically, it was significantly associated with improved PFS only in patients without extranodal extension.

Clinical Significance of the Lymph Node Ratio of the Second Operation to Predict Re-Recurrence in Thyroid Carcinoma

The purpose of this study was to establish the risk factors for re-recurrences and disease-specific mortality (DSM) in recurrent thyroid cancer. Patients with recurrent thyroid cancer who underwent initial thyroid surgery from January 2000 to December 2019 at Seoul St. Mary's Hospital (Seoul, Korea) were assessed. Clinicopathological characteristics and long-term oncologic outcomes were compared between patients with one recurrence (n = 202) and patients with re-recurrences (n = 44). Logistic regression and cox-regression analyses were conducted to determine the risk factors for re-recurrences and DSM, respectively. Receiver-operating characteristic curve analysis was performed to determine the cutoff value for lymph node ratio (LNR) as a predictor of re-recurrences. DSM was significantly higher in the re-recurrence group compared with the single-recurrence group (6.8% vs. 0.5%, p = 0.019). Surgical treatment at the first recurrence significantly lowered the risk of re-recurrences. Age (≥55), male sex, and LNR (≥0.15) were independent significant risk factors for re-recurrences in patients who underwent surgery at the first recurrence. Surgical resection is the optimal treatment for initial thyroid cancer recurrence. LNR at re-operation is more effective in predicting re-recurrence than the absolute number of metastatic LNs.

[Hemithyroidectomy or total thyroidectomy for low-risk papillary thyroid cancer? : Surgical criteria for primary and secondary choice of treatment in an interdisciplinary treatment concept]

The increase in small intrathyroid papillary thyroid cancer (PTC) observed worldwide over the past two decades, with no increase in cancer-specific mortality, has challenged the previous concept of total thyroidectomy as a one-size-fits-all panacea. After exclusion of papillary microcarcinomas, a systematic review of 20 clinical studies published since 2002, which compared hemithyroidectomy (HT) to total thyroidectomy (TT), found comparable long-term oncological outcomes for low-risk papillary thyroid cancer (LRPTC) 1-4 cm in diameter, whereas postoperative complication rates were markedly lower for HT. To refine individual treatment plans, HT should be combined with ipsilateral central lymph node dissection and intraoperative frozen section analysis for staging. Based on recent evidence from studies and in consideration of individual risk factors, patients with LRPTC can be offered the concept of HT as an alternative to the standard TT. A prerequisite for the treatment selection and decision is a comprehensive patient clarification of the possible advantages and disadvantages of both approaches.

A meta-analysis of the influence of body mass index on the clinicopathologic progression of papillary thyroid carcinoma

BACKGROUND

Papillary thyroid carcinoma (PTC) incidence has been increasing worldwide. Obesity, that is, having a high body mass index, is associated with the incidence of several cancers including colon, breast, esophageal, and kidney cancer. However, the association between obesity and the clinical features of PTC is still unknown. This study aimed to determine the impact of obesity on the clinical features of PTC.

METHOD

A database search was conducted for articles published up to 2020 on obesity and clinical features of PTC. Data were extracted from articles that met the meta-analysis inclusion criteria.

RESULTS

A total of 11 retrospective cohorts and 11,729 patients were included. Obesity was associated with the following variables in PTC patients: older age (difference in means = 1.95, 95% confidence interval [CI] 0.16-3.74, P = .03), male sex (odds ratio [OR] = 3.13, 95%CI 2.24-4.38, P < .00001), tumor size ≥1 cm (OR = 1.34, 95%CI 1.11-1.61, P < .002), multifocality (OR = 1.54, 95%CI 1.27-1.88, P < .0001), extrathyroidal extension (OR = 1.78, 95%CI 1.22-2.59, P = .003) and advanced tumor, node, metastasis stage (OR = 1.68, 95%CI 1.44-1.96, P < .00001). Preoperative serum thyroid-stimulating hormone level (difference in means  = 0.09, 95%CI 0.35-0.52, P = .70), Vascular invasion (OR = 0.84, 95%CI 0.56-1.26, P = .41), lymph node metastasis (OR = 1.07, 95%CI 0.87-1.32, P = .50), distant metastasis (OR = 1.14, 95%CI 0.64-2.04, P = .66), and recurrence (OR = 1.45, 95%CI 0.97-2.15, P = .07) were not associated with obesity.

CONCLUSION

Obesity was associated with several poor clinicopathologic prognostic features: older age, male gender, tumor size ≥1 cm, extrathyroidal extension, multifocality, and advanced tumor/node/metastasis stage. However, thyroid-stimulating hormone level, vascular invasion, lymph node metastasis, distant metastasis, and recurrence were not associated with obesity in PTC.

Role of adjuvant therapy with radioactive iodine in patients with elevated serum thyroglobulin after neck reoperation due to recurrent papillary thyroid cancer: a monoinstitutional comparative study

BACKGROUND

Most patients with papillary thyroid cancer (PTC) and lymph node metastases (LNM) undergoing reoperation do not show apparent disease after this procedure, but serum thyroglobulin (Tg) continues to be elevated in part of them. This study evaluated adjuvant therapy with ¹³¹I in these patients.

METHODS

Patients with PTC and LNM diagnosed after initial therapy were selected. Patients undergoing reoperation and those without apparent disease after this procedure, but with nonstimulated Tg ≥1 ng/ml 6 months after reoperation, were included. The first 25 patients were submitted to therapy with ¹³¹I (groups A) and the subsequent 30 patients did not receive this therapy (group B).

RESULTS

Groups A and B were similar. During further follow-up, 21 patients developed structural disease and 34 continued without detectable disease (eight achieved complete remission). The outcomes were similar in groups A and B. Patients with Tg reduction >50% after reoperation tended to have a lower risk of recurrence (22.7 versus 48.5%), notably distant metastases (0 versus 15.1%), and were more likely to achieve complete remission (28 versus 3%). Patients with LNM FDG-positive had a higher risk of recurrence (54.5 versus 11.7%) and were less likely to achieve complete remission (3 versus 29.4%) after reoperation.

CONCLUSION

Our results suggest that therapy with ¹³¹I apparently does not prevent recurrences among patients who continue to have elevated Tg after neck reoperation. Further studies involving these patients are necessary, especially those who are at high risk of recurrence.