Quantitative and morphologic change associated with breast cancer-related lymphedema. Comparison of 3.0T MRI to external measures

Abstract

Abstract Introduction: Lymphedema is a chronic disease of increasing importance to cancer survivors. A tape measurement tool used for lymphedema relies on indirect volume calculations based on external circumference, which may not reflect the true extent of abnormal fluid accumulation accurately. Fluid-sensitive MRI sequences may be able to delineate the severity of this condition more precisely and thus also monitor response to therapy.

Methods and results: Eight patients being followed by physical therapy for clinically diagnosed breast cancer-related lymphedema were recruited to participate in this study. External measurements and upper extremity MRI were performed on all subjects. Arm circumference, arm volume, and lymphedema volumes were calculated for each method. MR imaging detected lymphedema in all study subjects. Correlation was found between external circumferential measurements and with the 3.0T MRI (r=0.9368). There was poor correlation between lymphedema volumes calculated from clinical measurements and MR imaging (r=0.5539).

Conclusions: External measurements were not found to be an accurate measure of lymphedema volume associated with breast cancer lymphedema. MRI is a reliable means to obtain upper extremity circumferential and volume measurements. MRI is able to evaluate morphologic change associated with breast cancer-related lymphedema. Lymphedema research requires integrated use of tools to further describe the disease process over time, quantitate the distribution of tissue changes, and improve the sensitivity and specificity of the measurements.

FIG. 1.

Patient #7 is a 59-year-old woman with left-sided upper extremity lymphedema (B) imaged 1 year after surgery and radiation therapy. (A) and (C) Images from affected and unaffected arms, respectively. (D) Results of manual segmentation of subcutaneous tissues. (E) Edema volume base on signal intensity (WATs). (F) Corresponding STIR image. MRI calculation of edema volume was 144 mL within imaged arm volume of 909 mL.

FIG. 2.

Patient #3 is a 63-year-old woman, more than 10 years from breast cancer therapy. (A) Water-selective T1 weighted image (WATs) and (B) short tau inversion recovery (STIR).

FIG. 3.

Patient #4 is a 64-year-old woman with right-sided upper extremity lymphedema (B). Patient was imaged 10 years after surgery and radiation therapy. (A) and (C) Images demonstrate unaffected and affected arms respectively. (D) Results of manual segmentation of subcutaneous tissues. (E) Edema volume based on signal intensity generated from a fluid sensitive sequence (WATs). (F) Corresponding STIR image. MRI calculation of edema volume was 178 mL with a total arm volume of 891 mL.

FIG. 4.

Circumference and limb volume measures derived from external and MRI data. The correlation coefficient is high (r=0.9368).

FIG. 5.

Edema correlation between external and MRI measures. Poor correlation coefficient (r=0.5539).