SEER Inquiry System - View
Source 1: WHO Class Lung Tumors
Notes: June 2012
Source 2: CAP Protocol, Lung
MP/H Rules/Histology--Lung: Do we code adenocarcinoma in situ / BAC -- 8140/2, 8250/2, or 8250/3? See discussion.
Classification of lung malignancies has undergone a change. The bronchoalveolar carcinoma histology is being replaced by adenoca in situ and minimally invasive adenoca, using an evaluation of lepidic growth pattern.
We have a final diagnosis of "adenocarcinoma in situ / BAC" with a "Comment: the findings in the current biopsy are most compatible with low grade malignant lesions, which in this sample shows features of adenocarcinoma in situ (former bronchioloalveolar adenocarcinoma), since the proliferation of pneumocytes is limited to the alveolar lining with no evidence of invasion. However, classification of the lesion depends, per reference guidelines (Travis et al. J THOR ONCOL 2011 6,(2):244-275),
on its size and its overall histologic features, to rule out the presence of an invasive component and therefore can only be performed upon examination of it in its entirety, upon resection."
The radiation oncologist stages this T1N0M0, stage 1 BAC.
Assign 8140/2 for this case.
The comment for this case is consistent with information from the CAP protocol, which says "The diagnosis of bronchioloalveolar carcinoma requires exclusion of stromal, vascular, and pleural invasion—a requirement that demands that the tumor be evaluated histologically in its entirety. It is therefore recommended that a definitive diagnosis of bronchioloalveolar adenocarcinoma not be made on specimens in which the tumor is incompletely represented."
Since this tumor was not completely resected, code as adenocarcinoma in situ based on the information provided.