The aim of this study was to evaluate the influence of suspected prognostic factors on survival in the endemic goiter area. The retrospective review of 208 consecutive patients with differentiated thyroid cancer treated at I Department of General Surgery Collegium Medicum Jagiellonian University from 1983 to 1996. In the studied population there were 98 patients (47.1%) with follicular cancer and 110 patients (52.9%) with papillary cancer. The 182 (87.5%) female and 26 (12.5%) male patients had mean age 48.8 (range from 16 to 80 years). The mean follow-up period was 11.7 years with the longest time of observation 19 years and the shortest 6 years. All the patients were living in the endemic area. Patients with differentiated thyroid cancer have very good prognoses. The 10 year survival rate in case of follicular and papillary cancer were 87.6% and 90.24% respectively. The univariate analysis identified sex, age, histological subtypes (insular and tall cells variants), extrathyroidal extension, size of the tumour beyond 70 mm, lymph node and distance metastases as well as type of surgical procedures in III stage of disease as significant prognostic factors with major effect on survival. In the multivariate analysis extrathyroidal extension, distance metastases, recurrence and lymph node metastases influenced the survival. Early detection of differentiated thyroid cancer with the help of ultrasound examination with aspiration biopsy of suspected lesions, radical surgical procedures and good histological evaluation of the removed tissues guarantee very good treatment results.