Disease-Related Outcomes and Toxicities of Intensity-Modulated Radiation Therapy Following Lung-Sparing Pleurectomy for Malignant Pleural Mesothelioma: A Systematic Review.

Practical Radiation Oncology 2020 February 20 [Link]

Patel R, Ludmir EB, Miccio JA, Menon H, Barsky AR, Mesko SM, Kodali M, Lautenschlaeger T, Adeberg S, Simone CB 2nd, Verma V

Abstract

PURPOSE:

To explore the use of intensity-modulated radiotherapy (IMRT) after lung-sparing surgery in malignant pleural mesothelioma (MPM). Because severe toxicities have been documented following radiotherapy for MPM, its use remains controversial, especially as modern surgical management has shifted towards lung-sparing extended pleurectomy/decortication (eP/D). IMRT is an advanced technique that may allow for safer radiotherapy delivery, but there remains limited data (including no summative data) to support this notion.

METHODS AND MATERIALS:

We performed the first systematic review evaluating the safety and efficacy of post-pleurectomy IMRT (P-IMRT). A systematic review of PubMed using PRISMA guidelines was conducted for publications of all dates that specifically reported clinical outcomes and/or toxicities of P-IMRT in patients with MPM. Ten original studies were included in this review.

RESULTS:

Incidence of grade 3 pneumonitis ranged from 0-16%, with all but two studies reporting rates below 9%. Grade 4 and 5 pneumonitis were observed in less than 1.5% of cases, except in one publication that utilized hypofractionated radiotherapy to doses >60 Gy. Crude local failure rates ranged from 19-60%, median progression free survival ranged from 12-16 months, and median overall survival ranged from 19-28 months.

CONCLUSIONS:

P-IMRT produces relatively few higher-grade toxicities, and has reasonable disease-related outcomes, especially when delivering using conventionally-fractionated regimens to doses of 45-54 Gy and exercising careful attention to dose constraints during treatment planning. IMRT can thus be considered in well-selected patients in whom adequate survival following pleurectomy is expected. These data also support the initiation of the phase III NRG-LU006 trial of eP/D and chemotherapy with or without IMRT.