Table 2.

Criteria identifying the pneumonic-type adenocarcinoma.

Clinical criteri

-Cancer appears in a regional distribution, mimicking a pneumonic infiltrate or consolidation. The involved areas may appear to be ground glass, solid consolidation or a combination. -Areas involved can be one confluent area or multiple regions of disease. This region could be one lobe, multiple lobes or bilateral, but should involve a regional pattern of distribution. -This can be applied when there is a strong suspicion of malignancy, with or without a biopsy performed. -Discrete nodules are excluded such as ground glass/lepidic growth nodules. -This should not involve post-obstructive pneumonia due to tumors.

Pathologic criteria

-Distribution of adenocarcinoma should be diffuse throughout a region(s) of the lung rather than the usual single well-demarcated mass or multiple discrete well-demarcated nodules for cancer. -Involves an invasive mucinous adenocarcinoma, although a mixed mucinous and non-mucinous pattern may occur. -Show a heterogeneous mixture of acinar, papillary, and micropapillary growth patterns, although it is usually lepidic predominant.

Criteria as described by Detterbeck el al [2].