[Pulmonary cystic images as a presentation of a pleuropulmonary blastoma]

Pleuropulmonary blastoma, a distinctive neoplasm of childhood: report of three cases

BACKGROUND

Pleuropulmonary blastoma (PPB) is a rare, aggressive dysontogenetic neoplasm affecting children. It was identified as a distinct entity by Manivel in 1988 and later subdivided into three types on the basis of the histological pattern, with increasing malignancy from type I (cystic) through type II (solid/cystic) to type III (solid).

OBJECTIVE

To report on the imaging findings, clinical presentation, and differential diagnosis, mainly cystic malformations.

MATERIALS AND METHODS

We evaluated three children, age 2-4 years, with PPB.

RESULTS

One patient presented with unresolving pneumothorax and a multicystic mass, another with a mixed fluid/solid lesion, and the last with a solid heterogeneous mass.

CONCLUSION

Despite its rarity, PPB should be considered in the evaluation of cystic or solid masses in children with respiratory distress. Plain film radiography alone is unable to distinguish between PPB and cystic malformations. CT represents the gold standard, although MRI can show the imaging features of solid enhancing nodules inside fluid-filled cavities, a mass causing lung compression, mediastinal shift, frequent pleural effusion, and no chest wall invasion. No preoperative imaging can reliably differentiate between congenital cystic lesions and PPB type I.

Type I pleuropulmonary blastoma: a report from the International Pleuropulmonary Blastoma Registry

PURPOSE

Type I pleuropulmonary blastoma (PPB) is a rare, cystic lung neoplasm in infants characterized by subtle malignant changes and a good prognosis. Recurrences after type I PPB are usually advanced type II or type III neoplasms with a poor prognosis. This article describes the first collection of type I PPB cases, analyzes outcome based on treatments of surgery or surgery plus chemotherapy, and presents type I PPB management recommendations.

PATIENTS AND METHODS

Type I PPB cases from the International PPB Registry and literature were evaluated using standard statistical methods for outcomes based on age at diagnosis, sex, thoracic side, surgical extent, length of follow-up, constitutional/familial disease, pre-existing lung cysts, intrathoracic findings, and treatments (surgery or surgery and chemotherapy).

RESULTS

Thirty-eight type I PPB cases were identified: Registry (n = 30) and literature (n = 8). Twenty children had surgery alone; eight (40%) experienced recurrence; and four died. Eighteen children had surgery and adjuvant chemotherapy; one experienced recurrence and died. All recurrences were type II or III PPB. Recurrence-free survival was higher in the surgery + chemotherapy group (P = .01); overall survival did not differ (P = .18). The improved recurrence-free survival was found only in males. Four of nine children with recurrence survived.

CONCLUSION

Adjuvant chemotherapy appears to benefit type I PPB patients. Benefit limited to males requires broader substantiation. Salvage after types II and III recurrence is poor (four of nine; 44%). A rigorous surveillance schedule after type I PPB diagnosis might detect early recurrence and be an acceptable alternative to adjuvant chemotherapy.