Hepatocyte paraffin 1 immunoexpression in esophageal brush samples
Jun Zhang1, Anil V Parwani, Syed Z Ali
1Department of Pathology, The Johns Hopkins Hospital, Baltimore, Maryland 21287, USA.
Insights
Hepatocyte paraffin 1 (Heppar-1) immunostaining is a useful tool for identifying intestinal metaplasia (IM) in Barrett esophagus (BE) cytologic samples. This method offers moderate sensitivity and high specificity, aiding in difficult diagnoses.
Area of Science:
- Gastroenterology
- Cytopathology
- Oncology
Background:
- Intestinal metaplasia (IM) is a key feature of Barrett esophagus (BE).
- IM progression to dysplasia or adenocarcinoma necessitates accurate clinical identification.
- Morphologic diagnosis of IM in esophageal brushings can be challenging.
Purpose of the Study:
- To investigate the utility of hepatocyte paraffin 1 (Heppar-1) immunostaining.
- To evaluate Heppar-1 as a marker for IM in cytologic samples of BE.
Main Methods:
- Retrieved 22 esophageal brushing samples (11 BE with IM, 11 BE without IM).
- Confirmed diagnoses histologically via biopsies.
- Performed Heppar-1 immunostaining on Papanicolaou-stained cytospin slides.
Main Results:
- 82% (9/11) of BE with IM samples were Heppar-1 immunoreactive.
- 0% (0/11) of BE without IM (cardiac-type metaplasia) showed reactivity.
- Immunoreactivity was focal, cytoplasmic, and granular.
Conclusions:
- Heppar-1 demonstrated moderate sensitivity (82%) and high specificity (100%) for IM in BE.
- It is effective for limited cytologic samples previously stained with Papanicolaou.
- Recommended for morphologically challenging BE samples with suspected IM.
Background:
Intestinal metaplasia (IM) is often a component of Barrett esophagus (BE) and is characterized by a distinctive type of epithelium. Because IM has the potential to progress to dysplasia or adenocarcinoma, an accurate identification of its presence is important clinically. A cytopathologic diagnosis of IM on esophageal brushings by morphology alone can be difficult. The authors investigated the role of hepatocyte paraffin 1 (Heppar-1) immunostaining as a possible marker of IM in cytologic samples of BE.
Methods:
Eleven samples each of BE with and without IM diagnosed on esophageal brushings were retrieved from the cytopathology files of The Johns Hopkins Hospital over an 8-year period (1993-2001). All 22 specimens were confirmed histologically on subsequent tissue biopsies. Slides initially were prepared by cytospin and stained with Papanicolaou stain. After destaining, the slides were immunostained with hepatocyte paraffin 1 (Heppar-1) antibody at 1:100 dilution employing conventional methodology.
Results:
Among the samples of BE with IM, 9 of 11 samples (82%) were immunoreactive for Heppar-1, compared with 0 of 11 specimens of BE with only cardiac-type metaplasia. The immunoexpression was cytoplasmic and granular and was seen only focally in the glandular fragments.
Conclusions:
Heppar-1 was a moderately sensitive (82%) and highly specific (100%) immunomarker for IM in BE. It was easy to use in limited cytologic samples that originally were stained with Papanicolaou stain and is recommended for inclusion in morphologically difficult samples of BE with questionable IM. The immunostaining pattern predominantly was focal, necessitating a careful evaluation of positive reactions on cytologic samples.
