2772 - Cardiopulmonary Outcomes in Pediatric and Adult Lymphoma Patients Treated with Modern Radiation Techniques
Presenter(s)
I. Kizilbash1, W. S. Harmsen2, K. Aziz3, N. N. Laack II4, R. Tao5, W. G. Rule5, J. L. Peterson6, B. S. Hoppe7, S. M. Ansell8, U. Durani9, J. P. Abeykoon10, R. O. Kowalchuk11, S. C. Lester4, W. Breen4, and K. M. Frechette12; 1Mayo Clinic, Rochester, MN, 2Mayo Clinic, Department of Statistics, Rochester, MN, 3Johns Hopkins Radiation Oncology Kimmel Cancer Center, Baltimore, 4Department of Radiation Oncology, Mayo Clinic, Rochester, MN, 5Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 6Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, 7Mayo Clinic, Department of Radiation Oncology, Jacksonville, FL, 8Division of Hematology, Mayo Clinic, Rochester, MN, 9Mayo Clinic, Department of Medicine, Division of Haematology, Rochester, MN, 10Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, 11University of Virginia / Riverside Radiosurgery Center, Newport News, VA, 12Department of Radiation Oncology, Mayo Clinic Rochester, Rochester, MN
Purpose/Objective(s): Radiation therapy (RT) for mediastinal lymphomas has been associated with cardiopulmonary toxicity. Intensity modulated radiation therapy (IMRT) and proton beam radiotherapy (PBRT) combined with motion management techniques like deep inspiration breath hold (DIBH) and electrocardiogram (ECG) gated cardiac angiography aim to reduce cardiac substructure radiation exposure and mitigate long term cardiopulmonary sequelae. The implications of these modern technologies are underreported, and thus our aim is to evaluate cardiac and pulmonary outcomes associated with modern radiation techniques in patients treated for mediastinal lymphomas.
Materials/Methods: Adult and pediatric patients with mediastinal lymphoma treated with PBRT or IMRT between 2016-2025 at our institution were retrospectively reviewed. Relevant patient demographic, disease, and treatment characteristics were collected. Dosimetric data including mean and maximum dose of cardiopulmonary substructures including cardiac valves and coronary arteries were obtained. Hypertension (HTN), ECG data, cardiopulmonary events, and initiation of anti-hypertensives or statins after RT were collected.
Results: Eighty-nine patients were included in this study. The median follow-up was 2.5 years (IQR=0.7-4.6). The majority (79.1%) of patients had bulky (>7cm) disease. Most patients had HL (79.8%) or primary mediastinal B cell lymphoma (13.5%). The median age at the start of RT was 24 years (range 3-59). The median anthracycline dose received was 449 mg (range 449). Sixty-six patients (73.8%) received radiation as part of their initial course and the rest received RT due to relapse after chemotherapy treatment. Median radiation prescription was 3000 cGy (IQR=2800-3600). Across the cohort, there was only one (1.0%) major cardiac event (non-fatal cardiomyopathy 8 months post-RT) and no major pulmonary events. Nine (10.1%) patients were diagnosed with HTN, and six (6.7%) patients were taking anti-hypertensives or statins at the time of last follow up. There was no correlation between cardiac dosimetry variables and its impact on HTN and cardiac medication use (p>0.05). Abnormal ECG readings occurred in 32 (35.9%) patients post-RT. Mean left ventricle dose was not significant between those taking cardiac medication and those who did not (234.0 cGy and 47.6 cGy, respectively, p=0.87). There was no significant correlation for cardiac valve dose parameters for either HTN or cardiac medication use (all p>0.1938). Total lung mean dose, V10 and V20 were associated with risk of HTN (p=0.028, p=0.044, p=0.013, respectively).
Conclusion: In this cohort of mostly young adult mediastinal lymphoma patients treated with modern RT techniques, there was a very low rate of cardiac events and no major pulmonary events in the early follow up period. Longer follow up is needed to fully understand the impact of critical mediastinal structure sparing techniques on long term cardiac and pulmonary morbidity.