From January 1980 to December 1991, 137 patients suffering from Stage I EOC, were treated in our Institute. All patients underwent primary surgery with intensive staging procedures in 82% of cases; 12 patients underwent USO. Sixty-one out of 137 patients did not receive complementary treatment, 66 patients were treated with chemotherapy and 10 patients with i.p. P32. Three risk categories were identified, according to stage and grade: R1 = Stage IA-B G1 (45 cases); R2 = Stage IA-B G2-3 (31 stage); R3 = Stage IC all grades (53 cases). Forty out of 45 R1 cases did not receive adjuvant therapy; 12/31 R2 cases underwent surgical treatment only, 16/31 received adjuvant chemotherapy and 3/31 i.p. P32; 39/53 R3 patients were treated with chemotherapy and 6 with i.p. P32. Twenty-six patients (18.9%) suffered from a neoplastic relapse. Overall actuarial 5- and 10-year survival was: R1 = 96.3% and 89.9%; R2 = 79.6% and 79.6%; R3 = 79.2% and 62.3% respectively. There was no difference in survival between R2 treated and untreated patients, while difference emerged in R3 patients between chemotherapy and i.p. P32 groups. Five-year actuarial survival for the 26 patients suffering from recurrence was 40.5%.