Type III pleuropulmonary blastoma in a 7-month-old female baby with impending respiratory failure: a case report

A rare case of Pleuropulmonary blastoma type III with Immunohistochemical Study

Here we intend to document a rare case of PPB type III in a 2-year male presenting with an extensive tumor occupying the right hemithorax with immunohistochemical (IHC) study. Pleuropulmonary blastoma (PPB) is a rare variably aggressive, dysodontogenetic, childhood primary intrathoracic malignancy which in up to 25% of cases can be extrapulmonary with attachment to the parietal pleura. It is found in pediatric population under 5 years of age. It was initially proposed as a distinct entity by Manivel et al. in 1988. PPB is a proliferation of primitive mesenchymal cells that initially form air-filled cysts lined by benign-appearing epithelium (type I, cystic). Later on, the mesenchymal cells outgrow the cysts with formation of focal solid areas (type II, solid and cystic) and finally, mainly solid mass (type III, solid PPB).

Type II Pleuropulmonary Blastoma in a 4 Month Old Infant with Negative Dicer1 Mutation on Next Generation Sequencing

INTRODUCTION

Pleuropulmonary blastoma (PPB) is a rare, but aggressive tumor in the pediatric population. PPB is a dysontogenetic neoplasm of childhood that involves the lungs and/or pleura. Young relatives of children with PPB have an increased incidence of neoplasias and dysplasias. According to tumor tissue histopathology, PPB evolves from a cystic to solid state over time. PPBs can be sub-classified as type I (purely cystic), type II (having both cystic and solid elements), and type III (completely solid). Type II and type III tumors may be associated with metastasis, with the brain being the most common metastatic site. Due to the primitive nature of cells in the tumor mass, PPBs are very aggressive tumors that are resistant to therapy. The prognosis depends on the histopathology content and tumor type. Respiratory problems are the main complaint and diagnosis can be made only after additional examinations. Genetic relations through family members are associated with mutations in the DICER1 gene; between 60-80% of patients with PPBs are positive for DICER1 mutations. Mosaicism has also been reported.

AIM

The aim was to present a case of a 4 month-old infant with type II PPB, who had a negative result for DICER1 mutation in next generation sequencing. To detail the clinical presentation of this patient, we present radiographic and ultrasound findings and results of histopathological analysis, as well as genetic and scintigraphic findings and chemotherapy treatment.

CASE REPORT

Here we describe the genetic analysis of a patient with PPB who was negative for mutations in DICER1 and who had no relatives with disease. This patient underwent radical resection of the tumor and began therapy, but subsequently died after developing leukopenia and sepsis.

CONCLUSION

This case provides an example of a patient with PPB who was negative for DICER1 mutation upon genetic analysis and emphasizes the potential for disease that does not involve mutation of this gene.

Clinical analysis of early death in children with pleuropulmonary blastoma in a single center in China

OBJECTIVE

Pleuropulmonary blastoma (PPB) is a rare malignant tumor in childhood that is highly invasive and has poor prognosis. We retrospectively analyzed patients with PPB who died within 30 days in hopes of providing a basis for improving diagnosis and treatment.

METHODS

We retrospectively reviewed six children with PPB who died within 30 days of admission at our hospital from January 2004 to March 2018, including their clinical features, pathological diagnosis, course of treatment, and major causes of death.

RESULTS

Six patients (two female, four male; median age, 38 months) were included. All patients presented with respiratory symptoms. Chest imaging showed that all tumors had diameters greater than 10 cm, with varying degrees of serous effusion. Four patients underwent ultrasound-guided fine-needle aspiration (FNA), one patient underwent exploratory thoracotomy, and one underwent partial tumor resection. Five cases were type III, and another was type II. Four patients developed adverse events while waiting for pathological results after FNA, and four patients were treated with chemotherapy but their tumors failed to decrease in size one to two weeks later. The median hospitalization to death time was 17 days (range, 5-24 days).

CONCLUSIONS

PPB often presents with respiratory symptoms that rapidly develop into respiratory distress. The rapid tumor enlargement contributes to the disease's progression. Chemoreduction in such tumors is not obviously effective, and the mortality rate is high. The main causes of death were respiratory failure and sepsis. Further clinical studies will be required to evaluate the role of initial biopsy compared with upfront total excision.