Long-term results and prognostic factors in patients with differentiated thyroid carcinoma

Abstract

A multivariate analysis of the prognostic factors was carried out on a series of 546 differentiated thyroid cancers followed for 8 to 40 years. For survival, the highest risk factor was associated with age; tumors diagnosed in patients younger than 45 years had higher relapse‐free survival (RFS) and total survival (TS) rates and a slower growth rate. In children, although the RFS and TS at 15 years were high, they decreased later. The second independent prognostic factor was histology. There was no difference between papillary and follicular well‐differentiated (FWD) tumors, but follicular moderately differentiated (FMD) had lower TS and RFS. Among FMD cancers, relapses occurred earlier and the interval between relapse and death was shorter. The third factor was sex. Tumors tended to disseminate more in male than in female patients. The survival rate after relapse was the same, however, suggesting that the growth rates are not different. The presence of palpable lymph nodes also had a significant independent impact on both TS and RFS. Patients treated after 1960 have a better outcome than patients treated earlier, although they did not differ in age distribution, histologic characteristics, sex ratio, or incidence of palpable lymph nodes. The distribution of time intervals between treatment and relapse was not compatible with an exponential failure time model but fit with a log‐logistic model. Relapses can occur as late as 30 years or more after initial treatment. Elevated levels of circulating thyroglobulin have been observed in about 12% of the patients who had been in complete remission for longer than 20 years.

Prognostic Variables of Papillary Thyroid Carcinomas with Local Invasion.

“…In previous studies, gender was not shown to affect the outcome of treatment in well-differentiated thyroid cancer patients [1,3,4,11] or soft tissues were not necessarily associated with poor prognosis [12,23]. Although an aggressive surgical procedure including total resection was advocated for thyroid carcinoma with trachea or esophagus invasion [12], whether the resection should be performed with acceptable morbidity of the papillary thyroid carcinoma needs further investigation.…”

Factors Affecting Disease-Free Status of Differentiated Thyroid Carcinoma Patients

“…Many literatures showed that age is a strong predictor of outcome in DTC patients (Sobin et al, 2002;Durante et al, 2006;Toniato et al, 2008;Tubiana et al, 1985). In this univariate analysis, age was also significant factor for disease-free status.…”

Why radioiodine remnant ablation is right for most patients with differentiated thyroid carcinoma

“…First, 131 I therapy may destroy occult microscopic cancer foci, thereby decreasing the long-term risk of recurrent disease [9][10][11][12]. Second, it destroys any remaining normal thyroid tissue, thereby increasing the specificity of detectable serum thyroglobulin (Tg) and positive whole-body scintigraphy as markers for persistent or recurrent tumour [8,10,13].…”