Tumor growth and regression rates relative to tumor size: A clinical study of metastatic pulmonary nodules

Abstract

Patients with multiple discrete metastatic pulmonary nodules were serially monitored and tumor growth and regression rates were determined for selected measurable lesions. Tumor volume doubling time (TDT) in growing tumors or tumor volume halving time (THT) in regressing tumors was measured for multiple lesions. The objective of the study was to correlate tumor growth and/or regression rates with initial tumor size. A total of eight patients with 29 nodules of varying sizes was studied over observation periods the nodules regressed in response to specific chemotherapy. This study suggests that metastatic pulmonary nodules grow or regress at a relatively constant rate that is independent of pretreatment size. Growth and regression rates do not generally fluctuate, although tumor nodules may remain stationary or arrested for variable time periods. The study of tumor kinetics by clinical techniques is relevant to understanding tumor biology and to developing approaches to therapy.