Classic biphasic pulmonary blastoma: a case report and review of the literature

Abstract

Pulmonary blastomas are rare malignant tumors, comprising only 0.25-0.5% of all malignant lung neoplasms. Pulmonary blastomas are subdivided in three categories: well-differentiated fetal adenocarcinoma (WDFA), classic biphasic pulmonary blastoma (CBPB) and pleuropulmonary blastoma (PPB), which is currently regarded as a separate entity. The majority of patients with CBPB and WDFA are adults with an average age of 43 years. Tobacco use is identified as a causative agent. Symptomatology varies from asymptomatic (40%) to symptoms of a non-specific pulmonary disease. The most common roentgenologic pattern is a large peripheral nodule. The treatment of choice is surgical excision. The efficacy of adjuvant chemotherapy and radiotherapy is not yet established. The prognosis of pulmonary blastoma is very poor; overall five-year survival is 16%. WDFA appears to have a better prognosis. Adverse prognostic factors are biphasic type, tumor recurrence, metastasis at initial presentation, gross size of the tumor (>5 cm) and lymph node metastasis. On the basis of the available literature, an initial aggressive treatment that includes surgery and, wherever possible, postoperative chemotherapy and radiotherapy could be useful to prolong survival in patients with this rare lung neoplasm. We present a case of classic biphasic pulmonary blastoma in a 77-year old male and review the literature.