Radioactive Iodine Therapy Decreases Recurrence in Thyroid Papillary Microcarcinoma

Abstract

Background. The most appropriate therapy for papillary microcarcinoma (PMC) is controversial. Methods. We reviewed the therapy and outcome of 407 patients with PMC. Results. Three hundred-eighty patients underwent total thyroidectomy, and 349 patients received I-131 therapy. The median followup was 5.3 years. Forty patients developed recurrent disease. On univariate analysis, development of disease recurrence was correlated with histological tumor size > 0.8 cm (P = 0.0104), age < 45 years (P = 0.043), and no I-131 therapy (P < 0.0001). On multivariate analysis, histological tumor size > 0.8 cm, positive lymph nodes, and no I-131 therapy were significant. The 5-year RFS for patients treated with I-131 was 95.0% versus 78.6% (P < 0.0001) for patients not treated with I-131. Patients with lymph node metastasis who did not receive I-131 had a 5-year RFS of 42.9% versus 93.2% (P < 0.0001) for patients who received I-131. Conclusions. Recommend I-131 remnant ablation for patients with PMC, particularly patients with lymph node metastasis.

Retrospective Analysis of 255 Papillary Thyroid Carcinomas ≤2 cm: Clinicohistological Features and Prognostic Factors

“…RAI is usually considered based on risk assessment, however, it remains unclear whether ablative RAI is effective in reducing recurrences of small PTCs: Pelizzo et al [17] , Chow et al [18] and Creach et al [19] reported lower recurrence rates with RAI after thyroidectomy; in contrast, Baudin et al [20] , Sawka et al [21] and Schartz et al [22] failed to confirm this finding.…”

Increase of papillary thyroid microcarcinoma and a plea for restrictive treatment: A retrospective study of 1,391 prospective documented patients

“…Other studies could not find a significant correlation between multifocality and recurrent disease. 7,18,19,28 Multifocality is not a risk factor for disease recurrence in our statistical analysis, whereas the aggregate tumor size is highly significant for nodal recurrence. Ross et al 34 found similar overall recurrence rates with unifocal and multifocal PMCs; however, they also reported that patients with a multifocal disease who did not undergo a radical surgical concept (ie, total or near-total thyroidectomy) had greater rates of recurrence than patients with a similar treatment but unifocal tumors.…”

“…Nonetheless, it remains a matter of debate how dangerous these tumors really are and how necessary it is to take a radical approach to their treatment. 2,14,28,29 In this context the proposal to rename PMCs with a term, such as papillary microtumor, that does not include the word cancer has been suggested by various authors to improve the acceptance of less aggressive treatment. [25][26][27]30 In the literature, unfavorable outcomes are rare.…”

“…According to Hay et al, 5 neither a more extensive surgery nor radioiodine treatment was able to reduce recurrence rates compared with unilateral lobectomy. Conversely, Creach et al 28 and Chow et al 4 reported greater rates of recurrence in patients who did not undergo radioiodine treatment. They recommend a postoperative radioiodine treatment in patients with a PMC to reduce the recurrence risk.…”

Significance of Salivary Gland Radioiodine Retention on Post-ablation 131I Scintigraphy as a Predictor of Salivary Gland Dysfunction in Patients with Differentiated Thyroid Carcinoma

“…Postoperative 131 I therapy is used to destroy remnant thyroid tissue as well as microscopic metastases, and it affords the benefits of significant reductions in recurrence and cancer mortality rates in patients with papillary or follicular thyroid cancer [1,2]. It has also been reported that 131 I therapy improved the 5-year recurrence-free survival rates even of patients with papillary microcarcinoma [3]. Furthermore, administration of a therapeutic dose of 131 I enables visualization of persistent tumor tissue, via highly sensitive whole-body scanning, in patients with elevated levels of serum thyroglobulin [4].…”