Objective:

The imaging signs and clinicopathological features of pneumonia-type invasive mucinous adenocarcinoma (IMA) were analyzed to improve the accuracy of diagnosis.

Methods:

The imaging data and clinicopathological features of 23 patients with pneumonia-type IMA confirmed by pathology were retrospectively analyzed

and the imaging features of the disease were summarized.

Results:

Among the 23 pneumonia-type

IMA patients

13 were found to have cough as the symptom

among which 6 were found to have white phlegm. 11 cases of pneumonia were misdiagnosed at first diagnosis

among which 2 cases showed inflammation by first computed tomography (CT)-guided puncture biopsy. There were 9 cases of multiple lesions and 14 cases of single lesions. CT showed peripheral distribution in 16 cases

central distribution in 2 cases and diffuse distribution in 5 cases. There were 3 cases in the upper lobe

3 in the middle lobe and 17 in the lower lobe. On the imaging

there were less diseased solid components

patchy consolidation shadow with ground glass in 23 cases (100.0%)

“air bronchogram” sign in 17 cases (including “dead branch” sign in 11 cases)

and bulging sign of interleaf fissure in 6 cases. Cystic cavity or cavity shadow in 15 cases. There were 7 cases with irregular nodules in bilateral lungs or single lung. Enhancement scan showed all 23 cases were mild to moderate enhancement

among which 19 cases showed angiographic signs. No pleural effusion

lymph node enlargement or distant metastasiswas observed in the 23 patients. Microscopically

tall columnar cells were seen along the alveolar wall

with large amounts of mucus (mucous lakes) in the cytoplasm and alveolar cavities

and slight nuclear atypia.

Conclusion:

Although it is difficult to distinguish pneumonia-type IMA from pneumonia on images

it still has certain characteristic imaging findings

dynamic CT combined with needle biopsy can provide more diagnostic information.