AUTHOR=Denniston Kyle A. , Verma Vivek , Bhirud Abhijeet R. , Bennion Nathan R. , Lin Chi 

TITLE=Effect of Akimbo versus Raised Arm Positioning on Breast and Cardiopulmonary Dosimetry in Pediatric Hodgkin Lymphoma

JOURNAL=Frontiers in Oncology

VOLUME=6

YEAR=2016

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2016.00176

DOI=10.3389/fonc.2016.00176

ISSN=2234-943X

ABSTRACT=<sec id="ST1"><title>Purpose</title><p>In pediatric Hodgkin lymphoma (HL), radiotherapy (RT)-related late toxicities are a prime concern during treatment planning. This is the first study to examine whether arm positioning (raised versus akimbo) result in differential cardiopulmonary and breast doses in patients undergoing mediastinal RT.</p></sec><sec id="ST2"><title>Methods</title><p>Two treatment plans were made for each patient (akimbo/arms raised); treatment was per Children’s Oncology Group AHOD0031 protocol, including AP/PA fields. The anterior midline T6–T7 disk space was used as an anatomic reference of “midline.” Heart/lungs were contoured for each setup. For females, breasts were also contoured and nipple positions identified. Volumetric centers of contoured organs were defined and three-dimensional distances from “midline” were computed. Analyzed dosimetric parameters included V5 (volume receiving ≥5 Gy), V10, V15, V20, and mean dose. Statistics were performed using the Mann–Whitney test.</p></sec><sec id="ST3"><title>Results</title><p>Fifteen (6 females, 9 males) pediatric HL patients treated with mediastinal RT were analyzed. The median lateral distance from the breast center/nipple to “midline” with arms akimbo was larger than that with arms raised (8.6 vs. 7.7 cm left breast, <italic>p</italic> = 0.04; 10.7 vs. 9.2 cm left nipple, <italic>p</italic> = 0.04; 8.7 vs. 7.0 cm right breast, <italic>p</italic> = 0.004; 9.9 vs. 7.9 cm right nipple, <italic>p</italic> = 0.007). Raised arm position was associated with a median 2.8/3.0 cm decrease in breast/nipple separation, respectively. There were no significant differences in craniocaudal breast/nipple position based on arm positioning (<italic>p</italic> &gt; 0.05). Increasing breast volume was correlated with larger arm position-related changes in breast/nipple separation (<italic>r</italic> = 0.74, <italic>p</italic> = 0.06/<italic>r</italic> = 0.85, <italic>p</italic> = 0.02). Akimbo positioning lowered median breast V5, V10, V15, and mean dose (<italic>p</italic> &lt; 0.05), with no differences observed in patients with both mediastinal and axillary disease for any parameters (<italic>p</italic> &gt; 0.05). Arm position had no significant effect on cardiopulmonary doses.</p></sec><sec id="ST4"><title>Conclusion</title><p>Akimbo arm positioning may be advantageous to decrease breast doses in female pediatric HL patients undergoing mediastinal RT, especially in the absence of axillary disease.</p></sec>