Research

Long-term outcome of low-activity radioiodine administration preceded by adjuvant recombinant human TSH pretreatment in elderly subjects with multinodular goiter

Massimo Giusti^1*, Mauro Caputo², Iolanda Calamia¹, Mariaclaudia Bagnara³, Enrica Ceresola^1,2, Mara Schiavo², Michele Mussap⁴, Diego Ferone¹, Francesco Minuto¹ and Marcello Bagnasco²

• * Corresponding author: Massimo Giusti magius@unige.it

Author Affiliations

¹ Clinica Endocrinologica, Azienda Ospedaliera Universitaria "San Martino", Genoa, Italy

² Terapia Radiometabolica, Azienda Ospedaliera Universitaria "San Martino", Genoa, Italy

³ Fisica Sanitaria, Azienda Ospedaliera Universitaria "San Martino", Genoa, Italy

⁴ Laboratorio Analisi, Azienda Ospedaliera Universitaria San Martino, Genoa, Italy

For all author emails, please log on.

Thyroid Research 2009, 2:6 doi:10.1186/1756-6614-2-6

Published: 30 June 2009

Abstract

Background

Large multinodular goiter (MNG) in elderly people is a common finding which can require intervention. The long-term effect of radioiodine therapy on thyroid volume (TV) and function after recombinant human (rh) TSH pre-treatment was evaluated.

Methods

After baseline evaluation, 40 subjects over 60 years old with a large MNG were treated with ¹³¹I up to the activity of 600 MBq. Nineteen patients were pretreated with rhTSH (0.1 mg on 2 consecutive days; group 1) while 21 subjects underwent treatment without rhTSH pretreatment (group 2). TV was monitored every 6–12 months by ultrasonography. The median follow-up period was 36 months.

Results

At the baseline, the groups matched in terms of TV, 24-h radioiodine uptake (RAIU), urinary iodine and neck complaints. The number of subjects pretreated with anti-thyroid drugs was significantly (P = 0.01) greater in group 2 than in group 1; TSH was more suppressed (P = 0.003) and f-T3 was more elevated (P = 0.005) in group 2 than in group 1 patients. RhTSH increased 24-h RAIU in group 1 up to the baseline level observed in group 2. The ¹³¹I activity administered was similar in both groups. Adverse events were slight and similar in both groups. A permanent post-radioiodine toxic condition was reported only in 2 patients in group 2. After radioiodine therapy, hypothyroidism was observed in significantly more group 1 patients than group 2 patients (P = 0.002). While TV was reduced in both groups, the percentage TV reduction recorded at the last examination was significantly higher (P = 0.03) in group 1 than in group 2. MNG-related complaints were significantly reduced in both group 1 (P = 0.0001 vs baseline) and group 2 (P = 0.001) patients.

Conclusion

Low radioiodine activities after pretreatment with low-dosage rhTSH are able to reduce TV and improve MNG-related symptoms in elderly subjects.