[Evaluation of the relationship between chosen factors and results of whole body scintigraphy with 131I in patients with differentiated thyroid cancers].

Treatment and diagnostics with 131I play an important role in patients with differentiated thyroid cancer (DTC) after thyreoidectomy. The aim of the study was to assess the influence of some factors on ablative therapy results. Fifty seven patients with DTC were investigated (44 females--mean age 46.6 yrs, 13 males--mean age 55.6 yrs.). Papillary thyroid cancer was diagnosed in forty five patients (79%) however, follicular thyroid cancer in the others (21%). We performed post-therapeutic whole-body scan (WBS) after high fixed doses of 131I (median = 75 mCi) and six months later diagnostic WBS (mean 4.3 mCi) in every patient. Postoperative radioiodine uptake, levels of TSH and thyroglobulin (Tg) serum concentrations were assessed after thyroid hormones withdrawal before imaging. The absence of radioiodine uptake in the thyroid bed (effective ablation) was observed in 64.9% of patients. In other cases scans showed significantly diminished uptake of the tracer in the remnants. Statistically significant difference in TSH levels before and after radioiodine therapy (75.6 vs. 106.7 microIU/ml, p < 0.001) was found in all patients. However, effectiveness of the ablative therapy did not depend on radioiodine uptake, TSH and Tg levels before radioiodine treatment.