The American journal of surgical pathology
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Am. J. Surg. Pathol. · Apr 2010
SALL4 represents fetal gut differentiation of gastric cancer, and is diagnostically useful in distinguishing hepatoid gastric carcinoma from hepatocellular carcinoma.
The novel stem cell marker SALL4 has been identified as a diagnostic marker of germ cell tumors, especially yolk sac tumors, in gonadal organs. To clarify the significance of SALL4 as an oncofetal protein, we investigated SALL4 expression by immunohistochemistry in non-neoplastic stomach and gastric carcinoma with particular emphasis on á-fetoprotein (AFP)-producing gastric carcinoma, as AFP-producing gastric carcinoma shares expression of AFP and glypican 3 (GPC3) with yolk sac tumors and hepatic neoplasms. A total of 338 gastric carcinomas, 60 hepatocellular carcinomas, and 48 cholangiocellular carcinomas were studied by immunohistochemistry on tissue microarrays. ⋯ In addition, SALL4 expression was completely negative in hepatoblastoma (n=6) and hepatocellular carcinoma (n=60). SALL4 is an oncofetal protein similar to AFP and GPC3, but it represents fetal gut differentiation in gastric carcinoma. SALL4 is a sensitive marker for AFP-producing gastric carcinoma and is especially useful to distinguish hepatoid gastric carcinoma from hepatocellular carcinoma.
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Am. J. Surg. Pathol. · Apr 2010
Comparative StudyAccurately assessing her-2/neu status in needle core biopsies of breast cancer patients in the era of neoadjuvant therapy: emerging questions and considerations addressed.
Emerging data show that patients with operable, HER-2/neu overexpressed/amplified breast carcinomas have significantly better responses (more frequently obtaining pathologic complete response and greater percent disease-free survival) when treated with trastuzumab (Herceptin) simultaneously with neoadjuvant chemotherapy than with chemotherapy alone. With the increasing use of neoadjuvant therapies, clinicians require information on biomarkers including HER-2/neu status at the time of needle core biopsy. Concordance rates between fluorescence in situ hybridization (FISH)-determined HER-2/neu status on needle core biopsies and on subsequent excisional biopsies of the same tumor have not been well studied. Moreover, the practice of automatically performing ("reflexing") 2+ immunohistochemical (IHC) staining needle core biopsies for FISH analysis on the same sample needs to be validated. In this study, we set out to (1) determine the accuracy of HER-2/neu status as determined by FISH on needle core biopsy material compared with FISH on the subsequent excisional biopsy of the same tumor with special consideration of IHC 2+staining cases and (2) determine the constancy of HER-2/neu status in pre-neoadjuvant and post-neoadjuvant chemotherapy-treated tumor in the form of needle core biopsy and excisional biopsy samples, respectively. ⋯ Excellent overall concordance was achieved between FISH-determined HER-2/neu status on the needle core biopsy and that determined on the subsequent excisional biopsy of the same tumor. These results suggest that intratumoral heterogeneity of HER-2/neu assessed by FISH is not a significant confounding factor when analyzing smaller sized samples. Furthermore, 79% of 2+IHC staining needle core biopsy cases showed concordant FISH results in the needle core biopsy and subsequent excisional biopsy specimens. Our results show good concordance, however, larger cohorts need to be studied to verify this finding. HER-2/neu status remains unchanged in the majority of cases when comparing pre-neoadjuvant and post-neoadjuvant chemotherapy-treated specimens.