Clinical Outcome of Low-risk Differentiated Thyroid Cancer Patients after Radioiodine Remnant Ablation and Recombinant Human Thyroid-stimulating Hormone Preparation

• Published in: Clinical oncology (Royal College of Radiologists (Great Britain)) Vol. 24; no. 3; pp. 162 - 168
• Main Authors: Vianello, F, Mazzarotto, R, Mian, C, Lora, O, Saladini, G, Servodio, O, Basso, M, Pennelli, G, Pelizzo, M.R, Sotti, G
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-04-2012
• Subjects: Adenocarcinoma, Follicular - drug therapy; Adenocarcinoma, Follicular - pathology; Adenocarcinoma, Follicular - radiotherapy; Adenocarcinoma, Follicular - therapy; Adenocarcinoma, Papillary - drug therapy; Adenocarcinoma, Papillary - pathology; Adenocarcinoma, Papillary - radiotherapy; Adenocarcinoma, Papillary - therapy; Adult; Aged; Aged, 80 and over; Cell Differentiation; Combined Modality Therapy; Cross-Sectional Studies; Female; Follow-Up Studies; Hematology, Oncology and Palliative Medicine; Humans; Iodine Radioisotopes - therapeutic use; Male; Middle Aged; Neoplasm Staging; Radioactive iodine; Radiology; Recombinant Proteins - therapeutic use; remnant ablation; Retrospective Studies; rhTSH; Risk Factors; thyroid cancer; Thyroid Neoplasms - drug therapy; Thyroid Neoplasms - pathology; Thyroid Neoplasms - radiotherapy; Thyroid Neoplasms - therapy; Thyroidectomy; Thyrotropin - therapeutic use; Treatment Outcome; Whole Body Imaging; thyroid cancer; Radioactive iodine; rhTSH; remnant ablation
• ISSN: 0936-6555; 1433-2981
• DOI: 10.1016/j.clon.2011.02.011

Abstract Aim Recombinant human thyroid-stimulating hormone (rhTSH) has been approved in Europe as a preparation tool for radioiodine ablation of post-surgical thyroid remnants in patients with low-risk differentiated thyroid cancer (DTC). Published studies report that, both thyroid hormone withdrawal and rhTSH preparation result in similar rates of successful remnant ablation, but few studies have determined the effectiveness of rhTSH preparation on disease recurrence. We sought to determine the clinical outcome, considering both ablation success and disease recurrence, of low-risk DTC patients who underwent131 I ablation. Materials and methods This retrospective study describes the clinical outcome of 100 patients treated with131 I remnant ablation after preparation with rhTSH. After ablation, patients were classified as in complete remission, as having no evidence of persistent disease, or as having clinical recurrence on the basis of a subsequent diagnostic whole body scan with131 I, stimulated thyroglobulin and cross-sectional imaging studies. Results Overall assessment of ablation success was verified and obtained in 75% of patients (75/100). Considering only patients who underwent a diagnostic whole body scan and stimulated thyroglobulin without interfering anti-thyroglobulin antibody, complete ablation was obtained in 96% of patients (75/78). After a follow-up of about 4 years, 78 patients are in complete remission: 75 with initial ablation success and three who achieved a complete remission during subsequent follow-up. Among the remaining 22 patients, 21 have no clinical evidence of disease (NCED), indicating the inability to verify the complete remission or to detect residual disease, as in patients with positive thyroglobulin antibody, whereas one has persistent disease demonstrated only by stimulated thyroglobulin. No recurrences were observed. Of four patients initially classified as having persistent disease, one obtained a complete remission and two are now considered NCED. Conclusion Our data confirm the favourable outcome, with low rates of recurrence and persistent disease, of patients with low-risk DTC who underwent131 I ablation after rhTSH. Moreover, our results compare favourably with those reported in the literature in patients prepared with rhTSH, but also in patients prepared with hormone withdrawal.