Treatment outcomes in 23 thoracic primitive neuroectodermal tumours: a retrospective study.

OBJECTIVES: Thoracic primitive neuroectodermal tumour is an aggressive malignancy with poor survival despite multimodality treatment regimens. Early diagnosis of the tumour by histological, immunohistochemical, ultrastructural and cytogenetic techniques and early total surgical resection of the tumour with intensive chemoradiation may improve outcomes.

METHODS: Over 30 years, 23 patients (median age 29.5) with primitive neuroectodermal tumours (15 chest wall, 4 lung, 3 costovertebral sulcus and 1 anterior mediastinum) were diagnosed by transthoracic needle biopsy (43%) or excisional biopsy (57%). Treatment of a localized disease (Stage I and II) in 19 patients included surgery (wide excision of chest lesions in 11, 4 lung resections, excision of 3 costovertebral sulcus and 1 anterior mediastinal tumours, and resection of adjacent tissues involved by tumour en bloc) with adjuvant chemoradiation. Four metastatic chest wall tumours (Stage III) had chemotherapy and radiation alone.

RESULTS: Tumour recurred in 5 (2 chest wall, 2 costovertebral sulcus and 1 lung) requiring further chemotherapy, radiation and completion pneumonectomy for a lung recurrence. The incidence of recurrent tumour in 7 years for Stage I was 21 vs 40% (P=0.4) for Stage II lesions and 16% after the neoadjuvant chemotherapy vs 30% (P=0.4) after adjuvant chemoradiation. Four with recurrence, except one with a chest recurrence, succumbed to second relapse (78-96 months). All four Stage III chest tumours succumbed to advanced disease (30 months). The Kaplan-Meier disease-free survival of the overall group (23 patients) was 82±2% at 5 years and 64±3% at 10 years. The 10-year disease-free survival of 19 patients with localized tumours was 76%, but was high at 90% for chest wall tumours and low 33% for costovertebral sulcus tumours (P≤0.01). The 10-year disease-free survival was 86% for Stage I vs 60% (P=0.02) for Stage II tumours; and 83% for neoadjuvant vs 76% (P=0.06) for adjuvant chemotherapy and radiation.

CONCLUSIONS: The primitive neuroectodermal tumours are aggressive neoplasms with poor prognosis. Early diagnosis and total surgical excision of localized tumours with neoadjuvant or adjuvant chemotherapy and radiation improved disease-free survival.