Case of the week Details

1. Axial CT images

Heterogeneous segmental consolidation is seen in the apical segment of the right upper lobe. Areas of breakdown cavitations are seen within the consolidation. Adjacent to the consolidation there is some amount of ground glassing with interlobular septal thickening.

2. There is likely invasion of the mediastinal pleura with bulging of the pleura towards the mediastinum

3. The consolidation shows subsegmental bronchiolar cut-off.

Bronchogenic carcinoma presenting as persistent long standing consolidation

DISCUSSION:

• Lung cancer is a leading type of cancer, equal in prevalence to breast cancer . It is the leading cause of cancer mortality worldwide; accounting for ~20% of all cancer deaths
• The major risk factor is cigarette smoking which is implicated in 90% of cases and increase the risk of lung cancer, which can be divided by histological subtype :squamous cell lung cancer: 11x (men), 15x (women)small cell lung cancer: 10x (men), 25x (women)large cell lung cancer: 7x (men), 8x (women)

  lung adenocarcinoma: 4x (men and women)

L-PLADC  (localized pneumonic-type lung adenocarcinoma )  is  described as a special type of lung adenocarcinoma that presents as a focal consolidation involving < 50% of the area of a lobe . It is essential to differentiate clinical and imaging features between L-PLADC and localized pulmonary inflammatory lesion (L-PIL).

RADIOGRAPHIC FEATURES DIFFERNTIATING L-PLADC AND L-PIL

L-PLADC

Air bronchogram, irregular air bronchogram

Ground-glass opacity (GGO) component

and pleural retraction

L-PIL

Necrosis

Satellite lesions

Halo sign

Bronchial wall thickening, interlobular septa thickening, pleural attachment, and pleural thickening were more commonly seen in L-PIL

Differential diagnosis for chronic air space opacities

Cryptogenic organizing pneumonia

Granulomatosis with polyangiitis

Churg strauss pneumonia

Alveolar sarcoidosis

Post transplant lymphoproliferative disease

Lipoid pneumonia

Adenocarcinoma

Conclusion

In patients with chronic air space opacity , rule out underlying adenocarcinoma

Associated findings can help to narrow down the differentials

Biopsy to be considered in such cases

Reference :

• Siegel RL, Miller KD, Jemal A (2019) Cancer statistics, 2019. CA Cancer J Clin 69:7–34
• Pascoe HM, Knipe HC, Pascoe D, Heinze SB (2018) The many faces of lung adenocarcinoma: a pictorial essay. J Med Imaging Radiat Oncol 62:654–661
• Lee KS, Kim Y, Han J, Ko EJ, Park CK, Primack SL (1997) Bronchioloalveolar carcinoma: clinical, histopathologic, and radiologic findings. Radiographics 17:1345–1357
• Jung JI, Kim H, Park SH et al (2001) CT differentiation of pneumonic-type bronchioloalveolar cell carcinoma and infectious pneumonia. Br J Radiol 74:490–494
• Satoru N (2014) CT findings of pneumonic adenocarcinoma: comparison between invasive mucinous adenocarcinoma and nonmucinous adenocarcinoma. Global J 14:1–4

Dr. SHARNITHA JOHNSON
Fellow in Radiology
Manipal Hospital, Yeshwanthpur, Bengaluru.