[Assessment of response to chemotherapy by tumor marker in solid neoplasms]

The points at issue in the assessment of response to chemotherapy by tumor marker are discussed, and our guideline is proposed. In cancer clinics, many paradoxical movements of tumor marker are usually recognized in the situations such as heterogeneity changes of neoplasms, acute tumor cytolysis, non-peculiar rise of tumor marker, low level rise of markers near the basal level, which show paradoxical movements apart from clinical response to treatment. Then the guidelines must be settled based under the consideration of these phenomena and tumor marker kinetics. Partial response > = 65% decrease over 4 weeks; No change within < 65% decrease or < 40% increase over 8 weeks; Progressive disease > = 40% increase over 8 weeks. CR must not be defined.