A PULMONARY PAPILLARY ADENOMA IN A FILIPINO FEMALE: A CASE REPORT AND LITERATURE REVIEW

Abstract

TYPE: Case Report TOPIC: Lung Pathology INTRODUCTION: Pulmonary papillary adenomas (PPA) are extremely rare tumors with only 31 reported cases in literature. We present the 32nd case of a PPA in a patient presenting with hemoptysis. CASE PRESENTATION: A 23-year-old female with no comorbidities consulted for hemoptysis approximately 100cc in amount. Physical examination was unremarkable. CBC and bleeding parameters were normal. Chest radiograph revealed a left retrocardiac ovoid opacity and a contrast chest CT revealed a well-circumscribed enhancing mass in the left lower lobe measuring 2.5 x 3.2 x 2.6cm. Percutaneous needle biopsy of the lung mass revealed tumor cells forming papillary structures with fibrovascular cores lined by a single layer of cuboidal to low columnar epithelium, without nuclear atypia or mitotic activity. Immunohistochemically, TTF-1 and Napsin-A showed strong, diffuse positivity in the surface epithelial cells, with a low Ki-67 proliferation index, expressed only in 5-10% of the cells. The primary consideration is a pulmonary papillary adenoma. Further immunohistochemistry is essential to rule out other entities that may present similarly. The patient underwent a video-assisted thoracoscopic left lower lobectomy with no complications thereafter. DISCUSSION: The 31 existing cases in literature were reviewed, most are asymptomatic and are only incidentally seen on imaging. They are more commonly found in the lung periphery, usually in the lower lobes. Majority of patients are treated surgically without any recurrence or complications. CONCLUSIONS: PPAs are rare neoplasms. Biopsy and immunohistochemical staining are essential in their diagnosis and must be advocated in the work-up for patients with lung masses. DISCLOSURE: Nothing to declare. KEYWORD: papillary adenoma