Successful treatment of metastatic cerebral recurrence of pleuropulmonary blastoma

Treatment and prognosis of pleuropulmonary blastoma: A single-center report of 31 cases

OBJECTIVES

Pleuropulmonary blastoma (PPB) is a very rare and highly aggressive neoplasm occurring in children, mostly under 6 years of age. We assessed the clinical characteristics, treatment modalities, treatment outcomes, and prognostic factors affecting survival in patients with PPB treated at our institution over a 10-year period to improve the prognosis.

METHODS

From November 2008 to November 2019, 31 children (21 boys and 10 girls) with a median age of 30 months (ranging, 22 days to 54 months) were treated at our institution. Here we describe the patient characteristics, treatment modalities, and treatment outcomes. The Kaplan-Meier method was used to estimate the progression-free survival (PFS) and overall survival (OS). Log-rank test was performed for comparison between groups.

RESULTS

Three children were lost to follow-up and two were dead due to postoperative complications. Of the 26 patients included in the follow-up, 16 PPB patients displayed tumor-free survival. The 5-year PFS and OS were 60.4% and 60.1% respectively. By stratified statistical analysis, the 5-year PFS and OS of type I PPB were 100%, while those of type III PPB were 43.7% and 43%, respectively. The 5-year PFS and OS of complete tumor resection were 76.5% and 75.6%, respectively, while those with tumor residue were 31.3%. The 5-year PFS and OS combined with chemotherapy were 62.2% and 61.6%, respectively, while those without chemotherapy were 0%.

CONCLUSIONS

PPB is an aggressive neoplasm. The main factors related to the prognosis of PPB are pathological type, tumor resection degree, and postoperative adjuvant therapy.

Intraventricular topotecan in the successful treatment of recurrent CNS pleuropulmonary blastoma

Pleuropulmonary blastoma (PPB) is a rare pediatric tumor of the pleura and pulmonary mesenchyme, associated with pathogenic germline DICER1 mutations. Although the most common site of metastasis is the central nervous system (CNS), patients with CNS metastasis have dismal outcome. We report a case of a patient presenting with type II PPB and intracranial and bone metastases. We describe a multimodal therapy approach and highlight the use of intraventricular topotecan for isolated CNS recurrence. In addition, a new pathogenic germline mutation heterozygous for the c.1234delT of DICER1 was identified. Patient remains in remission 3 years after recurrence.

Children with progressive and relapsed pleuropulmonary blastoma: A European collaborative analysis

BACKGROUND

Children with progressive (PD) or relapsed disease (RD) of pleuropulmonary blastoma (PPB) type II/III are known to have a very poor outcome.

METHODS

A retrospective review of children registered in national and European databases and trials (2000-2018) with diagnosis of PPB type II/III and PD or RD was performed.

RESULTS

A total of 35 patients with PPB were analysed: patients with PD (n = 9) and RD (n = 26). Patients experienced PD at the median age of 3.9 years [range, 0.5-17.8] despite surgery, chemotherapy (CHT, n = 9) and radiotherapy (RT, n = 1) with a median time to progression of 0.58 years [range, 0.02-1.27] from diagnosis. All of them died. Patients suffered from RD at the median age of 4.3 years [1.7-15.1], median delay to relapse 1.03 years [range, 0.03-2.95]. RD occurred locally (n = 12), combined (n = 1) and in metastatic sites (n = 13): central nervous system (n = 11) and unspecified site (n = 2). Patients were treated with salvage CHT (n = 20), surgery (n = 10) ± RT (n = 10). After a median follow-up of 4.2 years [range, 2.1-14.6], a second complete remission (CR) was achieved in nine out of 26 patients. Patients were alive in the second CR (n = 6), in the third CR (n = 1), in partial remission (n = 2) and lost of follow-up (n = 1). Five-year event-free survival (EFS) and overall survival (OS) for patients with RD were both 37% (±19, CI 95%). Local therapy (surgery, RT) had a favourable impact on OS (p = 0.03 and 0.02, respectively).

CONCLUSIONS

Cure of patients with RD of PPB type II/III with multimodal treatment is possible but rare. Progressive PPB is fatal and patients need new treatment options.

Pleuropulmonary blastoma in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations

Pleuropulmonary blastoma (PPB) is a rare cancer occurring mainly during early childhood and often associated with germline DICER1 mutations. It is classified by the macroscopic appearance into three interrelated clinico-pathologic entities on a developmental continuum. Complete tumor resection is a main prognostic factor and can be performed at diagnosis or after neoadjuvant treatment that includes chemotherapy and in some cases radiotherapy. Optimal modalities of neo- or adjuvant treatments can be challenging taking into account potential long-term toxicities in this young population. This paper presents the recommendations for diagnosis and treatment of children and adolescents with PPB elaborated by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) within the European Union-funded project PARTNER (Paediatric Rare Tumours Network - European Registry).