Well-differentiated fetal adenocarcinoma: A very uncommon malignant lung tumor

Introdução

Introduction Fetal Adenocarcinoma is a very uncommon malignant tumor originating in the lung, and was first described by Kradin et al.¹ as a subtype of pulmonary blastoma, which resembled the epithelial component of the fetal lung without sarcomatous contingent. In 1984, the term fetal adenocarcinoma was introduced by Kodama et al.² 14 years later Nakatani et al. identified 2 groups: well differentiated occurring in young women and with a good prognosis and poorly differentiated with a similar prognosis to classical non-small cell carcinoma.³ Fetal adenocarcinoma has been considered in the WHO classification since 1999 as a solid adenocarcinoma with mucin production. However, a new international multidisciplinary classification, which focused on lung adenocarcinoma to standardize terminology and improve treatment and predict prognosis, does not consider fetal adenocarcinoma as a solid adenocarcinoma with mucin production but as a variant of invasive adenocarcinoma.⁴ We (The authors) report a case of a 38-year-old female patient with WDFA, and discuss the unusual features of this type of tumor. Case report A 38 year old woman presented with a one year history of dyspnea for which she was put on a short-acting bronchodilator with no further testing, in particular no chest X-ray considering she was in the early stages of pregnancy. Two months after delivery, she reported an aggravation of her dyspnea with no other respiratory or extra respiratory signs and was examined two months later. She had no significant past medical history; she had no history of smoking. The physical examination was normal. A chest X-ray (Fig. 1) showed a hilar...