Routine Prophylactic RT After Large-bore Thoracic Interventions Not Appropriate for Mesothelioma

Prophylactic radiation therapy is not recommended for patients with mesothelioma after large-bore thoracic interventions, according to a study published in the journal The Lancet Oncology.¹

Investigators compared prophylactic radiotherapy with deferred radiotherapy, given only when a procedure-tract metastasis developed, in patients with malignant pleural mesothelioma.

For this multicenter, open-label, phase 3 trial, researchers enrolled 203 patients with histocytologically proven mesothelioma, each of whom underwent large-bore pleural interventions in the 35 days before enrollment.

Participants were randomly assigned 1:1 to receive immediate radiotherapy at a dose of 21 Gy in 3 fractions within 42 days of the pleural intervention, or deferred radiotherapy given within 35 days of procedure-tract metastasis diagnosis.

There was no significant difference in the incidence of procedure-tract metastases between the immediate and deferred radiotherapy arms (9% versus 16%; 0.51 odds ratio; 95% CI, 0.19-1.32; P = .014).

The most common adverse events of immediate radiotherapy were skin toxicity and tiredness or lethargy within 3 months of receiving radiotherapy.

Reference

1. Clive AO, Taylor H, Dobson L, Wilson P, de Winton E, Panakis N, et al. Prophylactic radiotherapy for the prevention of procedure-tract metastases after surgical and large-bore pleural procedures in malignant pleural mesothelioma (SMART): a multicentre, open-label, phase 3, randomised controlled trial [published online ahead of print June 23, 2016]. Lancet Oncol. doi: 10.1016/S1470-2045(16)30095-X.