Outcomes after extrapleural pneumonectomy and intensity-modulated radiation therapy for malignant pleural mesothelioma

Abstract

Background: Malignant pleural mesothelioma is a locally aggressive tumor that is usually fatal. Extrapleural pneumonectomy (EPP) followed by hemithoracic irradiation has shown promise, but local failure remains a significant problem. To improve local control, we have used intensity-modulated radiation therapy (IMRT) as it allows better dose distribution to regions at risk of recurrence as well as reduced radiation to surrounding organs.

Methods: One hundred consecutive patients underwent EPP. At a median interval of 2.5 months from surgery, 63 patients received IMRT (median dose 45 Gy) with curative intent. Chemotherapy was not routinely administered.

Results: Tumors were right sided in 66 patients (66%) and nonepithelioid in 33 (33%). American Joint Committee on Cancer pathology stage was I in 6 patients (6%), II in 7 (7%), III in 72 (72%), and IV (T4) in 15 (15%). Fifty-four patients (54%) had ipsilateral nodal metastases. Perioperative mortality was 8%. Median overall survival (n = 100) was 10.2 months. For patients who received IMRT (n = 63), median overall and 3-year survival was 14.2 months and 20%. Of these, node-negative patients with epithelioid histology (n = 18) had median and 3-year survival of 28 months and 41%. Distant recurrences occurred in 33 of 61 evaluable patients (54%). Eight patients (13%) had local or regional recurrence, 5 of whom also recurred distally. Only 3 patients (5%) had recurrence within the irradiated field.

Conclusions: Intensity-modulated radiation therapy after EPP results in excellent local control for malignant pleural mesothelioma; however, distant metastases remain a significant problem and limit survival. This provides a strong rationale for combining aggressive local regimens with systemic therapy.