Objective: This study aimed to assess the ability of 3 criteria of rising CA-125 levels within the reference range to predict recurrence in patients with ovarian, primary peritoneal, and tubal carcinomas after complete clinical response to initial treatment.
Material and methods: Included were patients diagnosed during 1998 to 2008 who fulfilled the following criteria: CA-125 levels of 35 U/mL or greater at diagnosis and recurrence, full primary treatment with a complete clinical and radiographic response, follow-up according to schedule, and at least 2 CA-125 results within the reference range during follow-up. Three criteria of rising CA-125 values within the reference range were used for the prediction of recurrence: (1) an absolute increase of 5 U/mL or higher from the nadir value at completion of chemotherapy, (2) early signal of progressive disease criterion, and (3) a rise to an absolute level of 20 U/mL or greater.
Results: Of 82 patients who satisfied study inclusion criteria, 58 (70.7%) had disease recurrence. Early signal of progressive disease and a rise to an absolute level of 20 U/mL or greater were highly statistically significant predictors of disease recurrence (odds ratio, 12.62 [95% confidence interval, 2.71-58.7], P = 0.0012; and odds ratio, 6.7 [95% confidence interval, 2.18-20.54], P = 0.001, respectively) and preceded recurrence by a median of 3 and 3.3 months, respectively.
Conclusions: Our data indicate that the early signal of progressive disease criterion and a single rise to an absolute level of 20 U/mL or greater within reference limits are highly predictive of clinical recurrence, although the latter is simpler to use. However, whether this is of practical clinical value remains to be proven.