Differentiation of desquamative interstitial pneumonia (DIP) from pulmonary adenocarcinoma by immunocytochemistry.
OBJECTIVE
After a misdiagnosis of pulmonary adenocarcinoma as desquamative interstitial pneumonia (DIP), we investigated whether immunohistochemical markers could differentiate these conditions.


RESULTS
Three cases of DIP and one pulmonary adenocarcinoma masquerading as DIP were studied by light and electron microscopy. All cases were mucin-negative. The cases of DIP were CD68 positive but cytokeratin-negative. The adenocarcinoma was cytokeratin-positive (AE1/3 and CAM5.2), as well as showing some CD68-positive cells. Markers for carcinoma (CEA, Ber-EP4, and Leu M1) were negative in all cases. Ultrastructurally the adenocarcinoma appeared to be derived from Type II pneumocytes.


CONCLUSIONS
Before a diagnosis of DIP is made, cytokeratin markers should be used.
Department of Histopathology, Wythenshawe Hospital, Manchester, UK.
A E
AE
Mutton
P S
PS
Hasleton
A
A
Curry
P W
PW
Bishop
J
J
Egan
K B
KB
Carroll
S
S
Hanley
D000230:Adenocarcinoma / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D000328:Adult; D015415:Biomarkers / Q000032:analysis*; D003937:Diagnosis, Differential; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008168:Lung / Q000737:chemistry / Q000648:ultrastructure; D017563:Lung Diseases, Interstitial / Q000473:pathology*; D008175:Lung Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged
D015415:Biomarkers