Impact of radiation techniques on lung toxicity in patients with mediastinal Hodgkin’s lymphoma

Abstract

Purpose Mediastinal radiotherapy (RT), especially when combined with bleomycin, may result in substantial pulmonary morbidity and mortality. The use of modern RT techniques like intensity-modulated radiotherapy (IMRT) is gaining interest to spare organs at risk. Methods We evaluated 27 patients who underwent RT for Hodgkin’s lymphoma between 2009 and 2013 at our institution. For each patient, three different treatment plans for a 30-Gy involved-field RT (IFRT) were created (anterior-posterior-posterior-anterior setup [APPA], 5‑field IMRT, and 7‑field IMRT) and analyzed concerning their inherent “normal tissue complication probability” (NTCP) for pneumonitis and secondary pulmonary malignancy. Results The comparison of different radiation techniques showed a significant difference in favor of standard APPA (p < 0.01). The risk of lung toxicity was significantly higher in plans using 7‑field IMRT than in plans using 5‑field IMRT. The absolute juxtaposition showed an increase in risk for radiation pneumonitis of 1% for plans using 5‑field IMRT over APPA according to QUANTEC (Quantitative Analyses of Normal Tissue Effects in the Clinic) parameters (Burman: 0.15%) and 2.6% when using 7‑field IMRT over APPA (Burman: 0.7%) as well as 1.6% when using 7‑field IMRT over 5‑field IMRT (Burman: 0.6%). Further analysis showed an increase in risk for secondary pulmonary malignancies to be statistically significant (p < 0.01); mean induction probability for pulmonary malignoma was 0.1% higher in plans using 5‑field IMRT than APPA and 0.19% higher in plans using 7‑field IMRT than APPA as well as 0.09% higher in plans using 7‑field IMRT than 5‑field IMRT. During a median follow-up period of 65 months (95% confidence interval: 53.8–76.2 months), only one patient developed radiation-induced pneumonitis. No secondary pulmonary malignancies have been detected to date. Conclusion Radiation-induced lung toxicity is rare after treatment for Hodgkin lymphoma but may be influenced significantly by the RT technique used. In this study, APPA RT plans demonstrated a decrease in potential radiation pneumonitis and pulmonary malignancies. Biological planning using NTCP may have the potential to define personalized RT strategies

Pulmonary Toxicity after Total Body Irradiation—An Underrated Complication? Estimation of Risk via Normal Tissue Complication Probability Calculations and Correlation with Clinical Data

“…This theoretical approach offers the possibility to calculate and thereby anticipate the rate of pulmonary toxicities for a given RT regimen in order to establish a risk analysis. NTCP calculations have been used successfully for other entities [16,17] but have not been applied to a TBI cohort yet. In addition, a comprehensive discussion on influence factors for pulmonary toxicities is provided.…”

Radiation Therapy in the German Hodgkin Study Group HD 16 and HD 17 Trials: Quality Assurance and Dosimetric Analysis for Hodgkin Lymphoma in the Modern Era

“…This finding has been reported previously and may contribute to a greater risk of secondary malignancies in the long-term follow-up. 22 , 23 Therefore, a careful and individual risk–benefit analysis has to be performed without general recommendation of a uniform RT strategy as reflected by modern guidelines. 24…”

Kardiovaskuläre Risikoevaluation in der Behandlung des Hodgkin-Lymphoms – auf dem Weg zur individualisierten Planung?

“… Zu Recht wird von den Autoren auf das Armamentarium der modernen Radioonkologie verwiesen (Review [ 6 ]): Bestrahlung in tiefer Inspiration, intensitätsmodulierte Techniken oder Protonen-RT. Technikbedingt kann die RT-Belastung mediastinaler Organe beim HL differieren und eine Schonung ermöglichen [ 7 ]. Durch die detaillierte Konturierung kardialer Substrukturen (Kammern, Klappen, Erregungsleitsystem) und Berücksichtigung bei der Risikoermittlung ergibt sich eine differenzierte Weiterentwicklung der reinen MHD-Betrachtung.…”

“…Zu Recht wird von den Autoren auf das Armamentarium der modernen Radioonkologie verwiesen (Review [ 6 ]): Bestrahlung in tiefer Inspiration, intensitätsmodulierte Techniken oder Protonen-RT. Technikbedingt kann die RT-Belastung mediastinaler Organe beim HL differieren und eine Schonung ermöglichen [ 7 ].…”