Abstract
CEA doubling time was calculated in relapsed cases of lung cancer with elevated postoperative CEA levels. The mean value of CEA doubling time was 165.2 days in 16 cases with local recurrence, 86.7 days in 9 cases with pulmonary metastases, 57.7 days in 29 cases with distant metastases (excluding pulmonary metastases) and 48.6 days in 3 cases with carcinomatous pericarditis. There was significant difference in CEA doubling time between the cases with local recurrence and those with pulmonary metastases (P < 0.05), between the cases with local recurrence and those with distant metastases (P< 0.01), between the cases with local recurrence and those with carcinomatous pericarditis (P< 0.05).
Between CEA doubling time (X: days) and postoperative survival time (Y: days), there was a postitive correlation of Y= 2.79X+ 364.2 (R= 0.509, P<0.01).
The calculation of CEA doubling time may be useful to estimate the recurrent site when there is nothing but CEA elevation as a sign of recurrence, and moreover it may be a prognostic indicator.
