Association between pathological variants of papillary thyroid cancer and prognosis Background: Papillary thyroid carcinoma had a survival over 90% in stages I , II and III. Treatment failures are observed in advanced tumors, when there is lymph node involvement or when there is vascular invasion. Aim: To assess the prognostic value of pathological variants of papillary thyroid carcinoma. Material and Methods: Review of pathological records of patients with papillary thyroid cancer operated between January 1999 and December 2008 in a regional hospital. The pathological variant of the tumor was revised and classifi ed again as follicular variant, sclerosing, solid, tall cell variant, columnar variant, oncocytic, cribriform, microcarcinoma, insular variant and poorly differentiated. Results: The records of 51 females aged 48 ± 16 years and 12 males aged 42 ± 18 years were identifi ed. Forty patients had a well differentiated carcinoma (63%), 16 had a follicular variant (25%), four had a sclerosing variant and three other types. Capsule involvement was observed in six of 27 stage I, four of nine stage II, 20 of 26 stage III and one of one stage four tumor. Peritumoral lymphatic invasion was observed in 12 of 27 stage I, four of nine stage II, 21 of 26 stage III and one of one stage IV tumor. Lymph node relapse was observed in three patients without and nine patients with capsule involvement (p < 0.01) and in 11 of 38 patients without and 27 of 38 patients with lymphatic invasion (p < 0.01). Two patients in stage III and one in stage IV died. Lethality was 3%. Conclusions: Relapse of papillary carcinoma was associated with capsule involvement and lymphatic invasion. Tumor variants were not associated with relapse or mortality