Comparison of the outcome between cervical adenocarcinoma and squamous cell carcinoma patients with adjuvant radiotherapy following radical surgery: SGSG/TGCU Intergroup Surveillance

Abstract

Background: We conducted the present surveillance to clarify the significance of adjuvant radiotherapy and the cause of poor outcome of adenocarcinoma (AC). Methods: A total of 825 patients with FIGO stage Ib-IIb cervical cancer, who underwent type III radical hysterectomy in 10 institutes of SGSG/ TGCU Intergroup between April 1997 and March 2003, were enrolled in this study. There were 543 patients with squamous cell carcinoma (SCC) (261 in stage Ib1, 67 in Ib2, 83 in IIa, 132 in IIb) and 282 with AC (186 in stage Ib1, 39 in Ib2, 11 in IIa, 46 in IIb). Mean age of patients was 49.0 yrs (range: 19-84 yrs) in SCC and 46.6 yrs (range: 18-84) in AC. Two hundred and fifty-five patient with SCC and 69 with AC received adjuvant radiotherapy including CCRT. Results: The 5-year overall survival rate (OS) for patients with SCC and AC were 87.4% and 83.4%. The OS for stage I patients did not differ between SCC and AC. Stage II patients with AC showed significantly worse prognosis compared with SCC (54.5% vs. 87.4% in IIa, 63.3% vs. 78.8% in IIb). There was a significant difference in OS for patients receiving adjuvant treatment between SCC and AC (83.0% vs. 73.9%). Although the OS for stage I patients did not differ between SCC and AC, the OS for stage II patients with AC was significantly lower (86.9% vs. 50.0% in IIa, 75.5% vs. 61.1% in stage IIb). In patients with stage I, SCC showed significantly higher lymphnode involvement compared with AC (16.5% vs. 9.7% in Ib1, 46.3% vs. 20.1% in Ib2). The incidence of lymphnode involvement did not differ between SCC and AC in patients with stage II (36.4% vs.34.9% in IIa and 39.1% vs.45.5% in IIb). When patients had lymphnode involvement, the outcome of patients with AC showed significantly worse than those with SCC (46.4% vs. 72.3%). The local failure defined as recurrence in stump and pelvis was more frequent in patients with AC compared with SCC (24.6% vs.10.7%). Conclusions: Although the incidence of lymphnode involvement did not differ between AC and SCC, AC patients with lymphnode involvement showed significantly worse outcome. The present study indicates that lower sensitivity to radiotherapy might be an important cause for the poorer prognosis in AC.