oncology practice |
Natural history and clinical outcome of differentiated thyroid carcinoma: a retrospective analysis of 1503 patients treated at a single institution
1 Nuclear Medicine Division
2 Surgical Pathology Division
3 Biostatistics Unit, ‘Regina Elena’ National Cancer Institute, Rome, Italy
* Correspondence to: Dr R. Sciuto, Nuclear Medicine Division, Via Della Giuliana 83-A, 00195 Rome, Italy. Tel: +39-06-5266-3001; Fax: +39-06-5266-6011; E-mail: sciuto{at}ifo.it
Background: The study evaluates clinical presentation and outcome of differentiated thyroid cancer (DTC) on a large series of patients homogeneously managed.
Patients and methods: A cohort of 1503 DTC followed according to a standardized protocol entered the study. Main outcome measures were clinical presentation at the diagnosis, survival, morbidity and prognostic risk factors.
Results: Median age at diagnosis was 46 years. Papillary cancer and low pathological tumor–node–metastasis stages represented >80% of cases. Cancer specific survival at 5, 10 and 15 years was 98.6%, 94.7% and 87.4%; 10-year disease-free and progression-free survivals were 96.8% and 17.1%, respectively. Cancer-specific mortality rate was 2.5% [95% confidence interval (CI) 1.7% to 3.4%], recurrence rate was 0.6 % while morbidity rate was 12.6% (95% CI 11% to 14%). Response to radioiodine treatment is the strongest predictor of a good outcome in multivariate analysis (hazard ratio 211, P < 0.0001). Other independent predictor variables are sex, age, histology and distant metastases for survival and metastases for morbidity.
Conclusions: A rigorous initial therapeutic approach leads to a better survival and a very low morbidity. Patients who do not respond to radioiodine treatment have a worse prognosis.
Key words: morbidity, radioiodine therapy, survival, thyroid carcinoma
Received for publication October 25, 2008. Revision received February 4, 2009. Accepted for publication February 6, 2009.