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Several reports have shown the effect of time to fixation (cold
ischemia time), fixation time, or fixative type on the results of
IHC/FISH in breast cancer [ 27 ]. According to the Yamashita
et al., delay to fixation and duration of fixation may affect the
HER2 immunohistochemical score in a gastric cancer [ 27 ]. In
general, this is applicable to tissue fixation in esophageal adenocar-
cinoma. Therefore, it is critically important to optimize sample
preparation for HER2 testing in esophageal cancer.Patients with advanced/metastatic esophageal adenocarcinoma
may be too ill for diagnostic procedure such as gastrointestinal
endoscopy. Surgical resection is not a curative option for these
patients. Therefore, HER2 testing on cytological specimens such
as fine-needle aspiration biopsy samples of liver metastasis and
lymph nodes and effusions may be the only option available to
determine the HER2 status of these tumors with intent to targeted
therapies [ 28 , 29 ]. Cellblocks prepared from cytology material can
be successfully used for HER2 testing (Fig. 2 ). There is high con-
cordance rate (85%) for HER 2 status on cytological testing of
primary and metastatic esophageal adenocarcinoma [ 28 ]. This also
indicates that HER2 status is largely maintained during the process
of metastasis. Experience in using HER2 testing methods in cytol-
ogy material along with interpretation skills is critical for successful
results.2.2.3 Metastasis Sites
Including Cytology
Fig. 1 An example of a tissue microarray slide with multiple cores of separate
tumors for HER2 staining (hematoxylin and eosin × 20)Duminda Subasinghe et al.