Assessment of Arm Volume Using a Tape Measure Versus a 3D Optical Scanner in Survivors with Breast Cancer-Related Lymphedema.

ABSTRACT

Background: Lymphedema (LE) is a significant clinical problem for breast cancer survivors. While the water displacement test and circumferential assessment using a tape measure (TM) are common methods to assess differences in arm volumes, faster and more reliable methods are needed. Study purposes, in breast cancer survivors (n = 294), were to compare the average total arm volumes and interlimb volume ratios for women with and without a history of LE, using a TM and three-dimensional (3D), whole-body surface scanner (3D scan); compare the level of agreement between arm volumes and interlimb volume ratios obtained using the two devices; and evaluate the percent agreement between the two measures in classifying cases of LE using three accepted thresholds. Methods and Results: Measurements were done using a spring-loaded TM and Fit3D ProScanner. Paired t-tests and Bland-Altman analyses were used to achieve the study aims. For circumference and volume comparisons, compared with the 3D scan, values obtained using the TM were consistently smaller. In terms of level of agreement, the Bland-Altman analyses demonstrated large biases and wide limits of agreement for the calculated arm volumes and volume ratios. In terms of the classification of caseness, using the 200-mL interlimb volume difference criterion resulted in 81.6% overall agreement; using the >10% volume difference between the affected and unaffected arms resulted in 78.5% overall agreement; and using the volume ratio ≥1.04 criterion resulted in 62.5% overall agreement. For all three accepted threshold criteria, the percentage of cases was significantly different between the TM and 3D scan techniques. Conclusions: The 3D technology evaluated in this study has the potential to be used for self-initiated surveillance for LE. With improvements in landmark identification and software modifications, it is possible that accurate and reliable total arm volumes can be calculated and used for early detection.