David J Mulvihill1, Kevin McMichael1, Sharad Goyal1, Richard Drachtman2, Aaron Weiss2, Atif J Khan3. 1. Dept of Radiation Oncology, Rutgers Cancer Institute of NJ, New Brunswick, United States. 2. Dept of Pediatric Oncology, Rutgers Cancer Institute of NJ, New Brunswick, United States. 3. Dept of Radiation Oncology, Rutgers Cancer Institute of NJ, New Brunswick, United States. Electronic address: khanat@cinj.rutgers.edu.
Abstract
BACKGROUND: Involved field radiotherapy (IFRT) after cytotoxic chemotherapy has become the standard of care in treating pediatric patients with Hodgkin lymphoma. However, recent interest in shrinking the treatment volume to involved node radiotherapy (INRT) may allow lower doses to critical organ structures. We dosimetrically compared IFRT and INRT treatment approaches. METHODS: INRT treatment plans were retrospectively constructed from 17 consecutively treated pediatric patients identified with Hodgkin lymphoma who had been previously treated with conventional IFRT. The radiation doses delivered to organs-at-risk (OARs) with virtual INRT treatment plans based on INRT field design were then compared to the original IFRT treatment plans. Metrics for comparison included mean doses to organs and volumes of organ receiving at least 50% of the original prescription dose (V50%). A one-tailed, paired t-test was then performed to verify statistical significance at an alpha level of 0.05. RESULTS: All organs at risk compared in this investigation (kidneys, heart, thyroid, parotids, and lungs) had significantly lower doses of radiation with INRT when compared to IFRT (p<0.05). Furthermore, the volume of the breast receiving at least 50% of the initial prescription dose was statistically lower in the INRT plans. CONCLUSIONS: Utilizing the concept of INRT results in a reduction of radiation dose to critical organ structures in pediatric patients with Hodgkin lymphoma when compared to the more traditional method of IFRT.
BACKGROUND: Involved field radiotherapy (IFRT) after cytotoxic chemotherapy has become the standard of care in treating pediatric patients with Hodgkin lymphoma. However, recent interest in shrinking the treatment volume to involved node radiotherapy (INRT) may allow lower doses to critical organ structures. We dosimetrically compared IFRT and INRT treatment approaches. METHODS: INRT treatment plans were retrospectively constructed from 17 consecutively treated pediatric patients identified with Hodgkin lymphoma who had been previously treated with conventional IFRT. The radiation doses delivered to organs-at-risk (OARs) with virtual INRT treatment plans based on INRT field design were then compared to the original IFRT treatment plans. Metrics for comparison included mean doses to organs and volumes of organ receiving at least 50% of the original prescription dose (V50%). A one-tailed, paired t-test was then performed to verify statistical significance at an alpha level of 0.05. RESULTS: All organs at risk compared in this investigation (kidneys, heart, thyroid, parotids, and lungs) had significantly lower doses of radiation with INRT when compared to IFRT (p<0.05). Furthermore, the volume of the breast receiving at least 50% of the initial prescription dose was statistically lower in the INRT plans. CONCLUSIONS: Utilizing the concept of INRT results in a reduction of radiation dose to critical organ structures in pediatric patients with Hodgkin lymphoma when compared to the more traditional method of IFRT.
Authors: Vitaliana DE Sanctis; Alice DI Rocco; Maria Christina Cox; Maurizio Valeriani; Francesca Perrone Congedi; Dimitri Anzellini; Maria Massaro; Gianluca Vullo; Giuseppe Facondo; Flavia DE Giacomo; Marco Alfò; Daniela Prosperi; Patrizia Pizzichini; Sabrina Pelliccia; Agostino Tafuri; Maurizio Martelli; Mattia Falchetto Osti Journal: In Vivo Date: 2020 May-Jun Impact factor: 2.155