Pleuropulmonary blastoma early detection improves survival

Abstract

New research suggests that pleuropulmonary blastoma—the most common primary malignancy of the lungs in childhood—shows better outcomes in its purely cystic stage (type I), compared with other advanced and aggressive stages (type II or III). Yoav Messinger and colleagues also show that surveillance of the carriers of DICER1—the gene that shows a germline mutation in most pleuro pulmonary blastoma cases—might allow the earlier detection of type I pleuro pulmonary blastoma before its progression to type II or III and thereby improve outcomes. Pleuro pulmonary blastoma has three pathological types: type I (purely cystic), type II (cystic/solid), and type III (completely solid). However, not all cystic type I pleuro pulmonary blastomas progress to more aggressive stages: these non progressed or regressed cases are called type I regressed (type Ir). The researchers presented data from 350 confi rmed cases of pleuro pulmonary blastoma by the International Pleuropulmonary Blastoma Registry, which allowed a statistically robust analysis of survival and prognostic factors for pleuropulmonary blastoma. Analysing the data, Messinger and colleagues found that 33% (115/350) of pleuro pulmonary blastoma cases were type I or type Ir, 35% (124/350) were type II, and 32% (111/350) were type III or type II/III. For type I/Ir patients, the 5-year overall survival was 91% (95% CI 83–99). Overall survival was substantially better for type II versus type III (71% [95% CI 62–81] vs 53% [43–65], p=0·0061). According to the researchers, 5-year disease-free survival was also better for type II versus type III (59% [95% CI 50–70] vs 37% [28–48], p=0·0002). 97 patients with pleuro pulmonary blastoma were assessed for germline DICER1 mutations, and 64 (66%) had a heterozygous, deleterious DICER1 mutation. Julian Martinez-Agosto (David Geff en School of Medicine at UCLA, CA, USA) says, “This study reinforces the emerging view that identifying the type of pleuro pulmonary blastoma early on is prognostically important, as the presence of metastasis is associated with poor survival.” Apiwat Mutirangura (Chulalongkorn University, Bangkok, Thailand) comments, “[The researchers] describe the roles of germline DICER1 mutations in the clinical course of pleuropulmonary blastoma. Also, surveillance of DICER1 carriers might allow the earlier detection of type I pleuropulmonary blastoma. This is important in improving outcomes because earlier detection can prevent the disease from progression to type II or III.”