The possible existence of occult metastasis in patients with ovarian clear-cell carcinoma who underwent complete resection without any residual tumours

The objective of this study was to estimate the frequency of possible occult metastasis through long-term survival analyses in patients with clear cell carcinoma (CCC) who had undergone complete resection. During the period of 1990-2015, 799 patients with stage I-IV CCC were identified in the TOTSG database. Of these, a total of 528 patients without a residual tumor were enrolled in the study and classified into four groups: Group 1: FIGO stage IA-IB (N=104), Group 2: FIGO stage IC1 (N=170), Group 3: FIGO stage IC2/IC3 (N=98), and Group 4: FIGO stage II-III (no residual tumor: N=156). Cumulative incidences of recurrence (CIR) and death (CID) were examined. The median age was 54, ranging from 29-87. The 5-year CIR / CID of each group were as follows: Group 1 (7.3% / 3.8%), Group 2 (14.3% / 10.2%), Group 3 (37.7% / 18.4%), and Group 4 (46.5% / 33.8%), respectively {P