Radiotherapy after chemotherapy improves survival in paediatric MMGCT
The multimodal approach of chemotherapy followed by radiation appears to improve the long-term survival in paediatric patients with primary malignant mediastinal germ cell tumours (MMGCTs), a recent single-centre study has shown.
“In summary, primary MMGCTs are rare and associated with adverse outcome compared with their gonadal counterparts,” said researchers.
The electronic records of 427 MMGCT patients ≤18 years of age were retrieved from the Cancer Centre, Sun Yat-Sen University in China. Background information such as age, medical history, gender, tumour characteristics, chemo- and radiotherapy details and serum biomarkers were obtained.
Of the patients, 7.26 percent (n=31) were diagnosed with primary MMGCTs. After excluding those with mature teratomas, 24 patients remained (median age at diagnosis 16 years; 23 females), of which 20 (83.3 percent) had stage III disease and four (16.7 percent) had stage IV disease. [PLoS One 2017;doi:10.1371/journal.pone.0183219]
All patients received first-line cisplatin-based multidrug chemotherapy. Five received chemotherapy alone, four received adjuvant chemotherapy and 15 received neoadjuvant chemotherapy. Complete response was reported in three patients (n=12.5 percent), partial response in 17 (70.8 percent), stable disease in three (12.5 percent) and progression in one (4.2 percent).
“In the current study, all patients receiving first-line cisplatin-based chemotherapy obtained 95.8 percent [objective response rate]. However, due to the advanced stage of our cases, [complete response] was just achieved in 12.5 percent patients, which is lower than other reported results,” noted researchers. [Surg Today 1994:24:137-141]
Over a median follow-up of 46.2 months, seven patients relapsed, of which three died from distant metastases, two died from local progression and two censored after recurrence. The overall survival (OS) and disease-free survival (DFS) rates at 5 years were 82.3 and 64.9 percent, respectively.
Patients with seminoma had significantly higher 2-year OS (100.0 vs 74.2 percent; p=0.032) and DFS (100.0 vs 64.7 percent; p=0.043) rates compared with those with nonseminoma.
Surgery in the primary treatment did not seem to improve survival outcomes for the patients as three of five local failures were reported in those who received surgical resection and perioperative chemotherapy.
In comparison, there were no local recurrences in any of the patients who received adjuvant radiotherapy.
Univariate analysis showed that nonseminoma histology (p<0.032) and stage IV disease (p=0.025) were significantly associated with poorer 2-year OS, while nonseminoma histology (p=0.045) first-line chemotherapy with bleomycin, etoposide and cisplatin (p=0.029) were associated with poorer 2-year DFS.
“Our findings suggested that radiotherapy following chemotherapy in the first-line treatment strategy is effective in [seminoma] GCTs arising from the mediastinum with more safety and less toxic[ity], and may spare extensive surgery with high risk of incomplete resection and complications,” researchers said.
“A multidisciplinary approach including chemotherapy, surgery and radiotherapy is recommended to patients with MMGCTs. The role of radiation therapy in this setting merits further study,” they added.