Salvage radiotherapy for oligo-progressive malignant pleural mesothelioma

Paolo Ghirardelli; Davide Franceschini; Alessandro D'Aveni; Luca Dominici; Andrea Ravasio; Marco Marzo; Elisa Villa; Vincenzo Di Noia; Marta Scorsetti; Vittorio Vavassori; Giovanni L Ceresoli

doi:10.1016/j.lungcan.2020.11.022

Salvage radiotherapy for oligo-progressive malignant pleural mesothelioma

Lung Cancer. 2021 Feb:152:1-6. doi: 10.1016/j.lungcan.2020.11.022. Epub 2020 Nov 26.

Affiliations

¹ Department of Radiotherapy, Cliniche Humanitas Gavazzeni, Via Gavazzeni 21, 24125, Bergamo, Italy.
² Department of Radiotherapy, Humanitas Clinical and Research Center - IRCCS, Via Manzoni 56, 20089, Rozzano, Milan, Italy.
³ Department of Medical Oncology, Cliniche Humanitas Gavazzeni, Via Gavazzeni 21, 24125 Bergamo, Italy.
⁴ Department of Radiotherapy, Humanitas Clinical and Research Center - IRCCS, Via Manzoni 56, 20089, Rozzano, Milan, Italy; Humanitas University, Department of Biomedical Sciences, Via Rita Levi Montalcini 4, 20090 Pieve Emanuele, Milan, Italy.
⁵ Department of Medical Oncology, Cliniche Humanitas Gavazzeni, Via Gavazzeni 21, 24125 Bergamo, Italy. Electronic address: giovanni_luca.ceresoli@gavazzeni.it.

PMID: 33310300
DOI: 10.1016/j.lungcan.2020.11.022

Abstract

Objectives: No standard treatment option is available for patients with unresectable malignant pleural mesothelioma (MPM) progressing after upfront chemotherapy. We aimed to explore the role of focal radiotherapy (FRT) as a treatment modality for oligo-progressive MPM.

Materials and methods: In this retrospective study, consecutive patients pretreated with ≥1 lines of chemotherapy were included. Oligo-progressive MPM was defined as an unresectable disease with radiological progression at ≤3 sites according to a chest-abdominal contrast-enhanced computed tomography. Patients were treated with either stereotactic body radiotherapy (SBRT, ≥5 Gy per fraction) or hypo-fractionated radiotherapy (hypoRT, <5 Gy per fraction). Time to further systemic therapy (TFST) and local control (LC) after FRT were the primary endpoints. Biologically effective dose (BED) was calculated using three different alpha/beta models (1.5 Gy, 3 Gy and 10 Gy).

Results: From April 2006 to March 2019, 37 patients were treated on 43 pleural lesions; 16/37 (43 %) had undergone upfront multimodality treatment (MMT) including surgery. FRT was given in 22/37 (59.5 %) after one line of chemotherapy. SBRT was delivered for 26/43 lesions (60.5 %), hypoRT for 17/43 (39.5 %). Median TFST was 6 months (95 % CI 4.9-7.1). LC at 6 months and 1 year was 84 % and 76 %, respectively. Median TFST was longer in patients treated after 1 vs >1 line of chemotherapy (9 vs 4 months, p = 0.001) and in patients pretreated with MMT (6 vs 3 months, p = 0.021). Six-month LC was better in patients treated with a BED > 100 using alpha/beta 1.5 and 3. No ≥ G3 acute or late toxicities were reported.

Conclusion: FRT was feasible in selected patients with oligo-progressive MPM, allowing delay of further systemic therapies, with no severe toxicity. FRT was more effective when performed at progression after one line of systemic therapy. Our results suggest a radio-resistant behavior of MPM.

Keywords: Hypo-fractionated radiotherapy; Malignant pleural mesothelioma; Oligo-progression; Radiotherapy; Stereotactic body radiotherapy.

MeSH terms

Combined Modality Therapy
Humans
Lung Neoplasms* / radiotherapy
Mesothelioma* / radiotherapy
Mesothelioma, Malignant*
Pleural Neoplasms* / radiotherapy
Retrospective Studies