A prognostic analysis of primitive neuroectodermal tumor for postoperative recurrent patients and a literature review / 解放军医学杂志

ABSTRACT

Objective To analyze the prognostic factors of primitive neuroectodermal tumor (PNET) for postoperative recurrent patients. Methods Thirty patients admitted from Jun. 2008 to Dec. 2014 and diagnosed as PNET were retrospectively analyzed. Postoperative recurrence happened in all of the patients, of whom 2 received surgery alone, 15 received surgery and chemotherapy without radiotherapy, 3 received surgery and radiotherapy without chemotherapy, and 10 received surgery, radiotherapy and chemotherapy. Kaplan and Meier method was employed to draw the survival curve of the postoperative recurrent PNET patients, and to evaluate the effects of sex, age, radical resection, therapeutic method and relapse-free interval (RFI) on the overall survival (OS). Log-rank method was used to test the significance of differences, and Cox regression was used to analyze all the factors listed above. The literatures related to PNET published domestically and abroad in recent 20 years were reviewed. Results The overall median survival time was 30 months. The OS rates of 1, 3 and 5 years were 80.0%, 44.1% and 20.7%. Local recurrence happened in 26 patients (86.7%), and distant recurrence in 4 patients (13.3%). The overall median RFI was 4 months, and the RFI rates of 6 months, 1 year and 2 years were 33.3%, 16.7% and 6.7%, respectively. The overall median recurrence-free survival (RFS) time was 14 months, and the PRS rates of 1, 3 and 5 years were 60.7%, 16.9% and 8.4%, respectively. The univariate analysis showed that radical resection, radiotherapy and RFI ≥ 6 months predicted significantly better outcome (P=0.033, P=0.006 and P=0.001). The multivariate analysis revealed that radiotherapy and RFI ≥ 6 months were the independent prognosis factors (P=0.047 and P=0.012, respectively). One thousand six hundred and eight cases of recurrent PNET patients were reported abroad since A.D. 2000. The initial recurrence was most often distant only (1089 cases), followed by local only (292 cases) and both distant and local (227 cases). Median RFI ranged from 0.1 to 128 months and the 5-year RFS ranged from 13% to 28%. Major factors influencing RFS included RFI ≥ 24 months, stage of disease at initial diagnosis and high dose treatment. Conclusions The prognosis of PNET patients with postoperative recurrence is very poor. Radiotherapy may have important significance to the PNET patients. RFI <6 months may seriously impact on the OS of PNET patients, but throw no significant influence on the post recurrence survival.