Sclerosing Pneumocytoma with a Wax-and-Wane Pattern of Growth: A Case Report on Computed Tomography and Magnetic Resonance Imaging Findings and a Literature Review

Abstract

Sclerosing pneumocytoma (SP) of the lung is a rare benign neoplasm. Here, we describe an unusual presentation of SP with a wax-and-wane pattern of growth in a 47-year-old woman. Tumor diameter decreased over a 3-year follow-up period and then increased on serial follow-up computed tomography scans. The mass showed high signal intensity on both T1- and T2-weighted chest magnetic resonance imaging (MRI) and early enhancement with a plateau on dynamic MRI. We speculate that intratumoral bleeding and resorption processes accounted for the changes in tumor size.

Keywords: Magnetic resonance imaging; Multidetector computed tomography; Pulmonary sclerosing hemangioma.

Fig. 1. Sclerosing pneumocytoma with wax-and-wane growth pattern in 47-year-old woman.

A-C. Initial (A) and 1-year (B) and 3-year follow-up (C) contrast-enhanced computed tomography (CT) scans show heterogeneously enhancing mass in left upper lobe. Mass decreases in diameter from 3.1 to 2.1 cm and then marked increase to 3.4 cm on serial CT scans. D. Serial volume graph chart obtained from three-dimensional CT data using automated segmentation technique during follow-up shows wax-and-wane pattern. E, F. Mass shows iso- to higher signal intensity (SI) than that of muscle on T1-weighted magnetic resonance (MR) image (E) and heterogeneously high SI on fat-saturated T2-weighted image (F). G. Dynamic contrast-enhanced MR images and corresponding graph of SI versus time show early enhancement without peak point and subsequent plateau pattern. H. Gross findings show well-demarcated, solid mass with fibrous matrix and areas of hemorrhage. I. Well-demarcated mass with small cystic spaces filled with blood was observed on microscopic examination (hematoxylin and eosin staining, × 12.5).