Primary pleuropulmonary sarcoma: what we know about it?

With the word ‘primary pleuropulmonary sarcoma’ we consider a heterogeneous group of tumors derived from cells of mesenchymal origin, which could arise from the lung and pleura. Primary chest wall sarcomas are rare, representing 0.2% of all lung cancers and 5% of all thoracic neoplasms [1]. As often happens with a rare disease, available data are derived from small cohorts of patients and often from single institution experiences and, frequently, from retrospectives analyses. Furthermore, unlike soft tissue and bone sarcomas, there are not specific guidelines dedicated for this disease, leaving to every center experience the patient’s charge. What are the major changes observed in the recent years and which are the open questions about this disease? The major advances arise from the pathologic area, as a matter of fact from the first morphological classification of pulmonary sarcoma, which provided the differentiation in spindle cell and round cell, we observed continuous changes in terminology and diagnostic criteria, in parallel with the evolution of diagnostic techniques, such as the immunohistochemistry and cytogenetic analysis [2,3]. The discover of the t(X;18) (p11.2;q11.2) translocation has led, in recent years, to a considerable increase in the diagnosis of pulmonary synovial sarcoma [4]. Moreover, the availability of multiple cytokeratin antibody tests has improved the differential diagnosis with other solid tumors, such as the sarcomatoid carcinoma and the diffuse malignant mesothelioma [3]. The improvement of radiologic diagnostic tools (i.e., in the field of vascular imaging) have led to a more precise localization of the diseases, that could arise from intravascular location, allowing for further separation of pulmonary endovascular from other parenchymal-based sarcomas [3]. The other side of the coin is that these continuous changes in terminology and diagnostic criteria make difficult the execution of a specific systematic review of the literature. Surgical resection with pathological free margins, regardless of the histologic tumor type, is widely accepted as initial treatment for primary pleuropulmonary sarcoma and this is also the most relevant prognostic factor able to determine the patient outcome [5–8]. Lobectomy or, when necessary, pneumonectomy remain the gold standard for the initial treatment of this disease after an