Endocrine Abstracts (2011) 26 P484

Seventh UICC/TNM staging criteria for medullary thyroid carcinoma: is there any prognostic advantage?

M Martinho1, T Azevedo1, F Carrilho2, T Martins1, C Ribeiro2, M Melo2, N Cunha1, M J Rascão1, A Neves1, P Gilde1, J L Pires1, C Cruz1, C Oliveira1, J Neto1, S Oliveira1, F Valido1, I Gomes1, M Carvalheiro2 & F Rodrigues1

1Instituto Português de Oncologia de Coimbra FG EPE, Coimbra, Portugal; 2Hospitais da Universidade de Coimbra EPE, Coimbra, Portugal.

Background and aims: The value of the revised (2009) UICC/TNM criteria for medullary thyroid cancer (MTC) is not established. We aimed to evaluate its predictive value, analyzing the consequences of the inclusion of T3N0M0 patients previously included in stage III of the 6th edition, in stage II of the 7th.

Patients and methods: We retrospectively analysed the clinical records of 85 patients operated for MTC and followed in two tertiary hospitals in the central region of Portugal between 1978 and 2009; staging was done according to both the 6th and 7th UICC/TNM criteria.

Results: Mean age at first operation was 52.1± years (range: 6–86 years); 52 patients (61.2%) were female. Fourteen patients (16.5%) were MEN2A carriers and 2 were MEN2B (2.4%). Mean follow-up time was 5.9 years. There were 26 (30.6%), 11 (12.9%), 17 (20%) and 31 (36.5%) patients in 6th edition stage I, II, III and IV, and 26 (30.6%), 22 (25.9%), 6 (7.1%), in 7th stages I, II, III and IV, respectively. Eleven patients (12.9%) were reclassified according to the 7th edition, changing from stage III to stage II. Five-year survival for stage I, II, III and IV according to the 7th was 100, 87, 100 and 52%, respectively. The two patients who died in stage II would have been classified as stage III according to the 6th edition. Five-year survival rate in the new classification for stage II was 100 and 86% for stage III.

Conclusions: According to our data, the last UICC/TNM classification did not provide better prognostic information for low and intermediate risk patients, however further studies with a longer follow-up and a larger number of patients are needed to confirm these findings.