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.