J Cancer 2017; 8(17):3531-3537. doi:10.7150/jca.19984 This issue Cite
Research Paper
1. Department of Medical Oncology, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangzhou, China;
2. Department of Nursing, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangzhou, China;
3. Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangzhou, China;
4. Department of Pharmacy, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China;
5. Department of Experimental Research, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.;
6. Department of Pathology, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangzhou, China;
7. Department of Gastric Surgery, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
* Miao-Zhen Qiu, Si-Mei Shi and Min Chen contributed equally to the manuscript.
Purpose: Patients with advanced or metastatic adenocarcinoma of the stomach or esophagogastric junction for whom trastuzumab therapy is being considered, assessment for tumor human epidermal growth factor receptor-2 (HER2) status is necessary. Can the HER2 status and Lauren classification of the biopsy sample truly represent the HER2 status in the gastric cancer?
Methods: Formalin-fixed, paraffin-embedded sections of 116 pair surgically resected and biopsy specimens as well as 80 pair primary and metastatic lesions of gastric cancer patients were analyzed. Protein expression was assessed using immunohistochemistry (IHC) and graded by the modified scoring criteria for gastric cancer. Gene amplification was evaluated by fluorescence in situ hybridization (FISH) in IHC 2+ cases.
Results: The positive rate of HER2 was 11.2% in both surgical and biopsy samples. The consistent rate of HER2 expression was 91.4% (106/116) between biopsy and surgical samples, P=0.666. The positive rate of HER2 was 20.5% in primary and 15.9% in metastatic samples, P=0.1876. The consistent rate of HER2 expression was 90.9% (40/44) between primary and metastatic samples, P=0.580. The consistent rate of Lauren classification was 64.7% (75/116) between biopsy and surgical sample, and 92.5% (74/80) between primary and metastatic samples.
Discussion: For gastric cancer, HER2 expression and Lauren classification were highly homogenous in biopsy and surgical samples, primary and their corresponding metastatic samples. The high concordance observed between these two cohorts indicated that the HER2 examination and Lauren classification of biopsy samples from the primary tumor could well represent the metastatic lesions of the patients.
Keywords: HER2, Gastric Cancer, Immunohistochemistry, FISH.