Abstract:Objective To investigate CT features and reasons for the misdiagnosis of nodular or mass-like type pulmonary cryptococcosis（PC）. Methods The clinical manifestations and imaging data of 60 cases with nodular or mass-like type PC confirmed by pathology in the Affiliated Hospital of Nanjing University of Chinese Medicine from June 2011 to December 2021were analyzed retrospectively. Results Clinical manifestations: respiratory symptoms were associated with 28 cases, whereas 26 cases were asymptomatic. Imaging findings: 22 cases were in unilateral single lung lesion, 22 cases were in unilateral multiple lung lesions, 16 cases were in bilateral multiple lesions. Fifty-five cases with oval shape, including 38 cases with the long axis are parallel to the pleura, 28 cases with clustering and fusion tendency. Fifty-two cases were uniform in density. Thirteen cases with moderate enhancement, 4 cases with avid enhancement. Moreover, there were 24 cases with proximal air bronchogram, 45 cases with halo sign. Thirteen cases were followed and the volume doubling time ranged from 3.9 to 236.8 days, with the median 24.9 days. Thirty-seven cases were initially misdiagnosed. ConclusionsNodular or mass-like type of PC lesions usually occurs in the inferior lobe of both lungs and close to the pleura, and the long axis is parallel to the pleura. Halo sign and proximal air bronchogram are more specific manifestations. Multiple nodular masses with clustering and fusion tendency are highly suggestive of a PC. Cryptococcal capsular polysaccharide antigen detection can be used in clinical, and puncture biopsy can be performed if necessary.