HER2 Status in Gastric Cancer: Comparison between Primary and Distant Metastatic Disease

Abstract

HER2 (human epidermal growth factor receptor-2) assessment in histological samples of gastric cancer is essential to determine which patients might benefit from trastuzumab therapy. HER2 is often evaluated in primary tumor even if trastuzumab therapy is used to treat metastatic disease. However, the exact relationship in terms of HER2 status between primary and metastatic tumors has not been fully clarified. We aimed to evaluate the HER2 status concordance between primary gastric cancer and corresponding distant metastasis. HER2 status was evaluated by IHC (immunohistochemistry) and/or FISH ( fluorescence in situ hybridization) in 41 patients in primary gastric cancer and in paired metastasis. HER2 was assessed according scoring criteria applied in clinical approach. HER2 positivity was found in 14,6 % primary tumors and in 24,4%corresponding metastasis. HER2 concordance rate between primary and metastasis was 80,5 % (K-value = 0,388). Eight/41 (19,5 %)cases resulted discordant: 6 patients with metastatic HER2 positive lesions were found HER2 negative in primary cancers while 2 patient HER2 positive in primary lesion showed a negative conversion in metastasis. Our results showed a good concordance in terms of HER2 status between primary and metastatic lesions, as well as in biopsy and surgical removed specimens. However, the higher rate of HER2 positive status found in metastatic lesions underlined the importance of HER2 assessment in all samples obtained from different sites of gastric cancer disease.

Discordance and Conversion Rates of Progesterone-, Estrogen-, and HER2/neu-Receptor Status in Primary Breast Cancer and Brain Metastasis Mainly Triggered by Hormone Therapy

“…An overview of all receptor changes within the 24 patient pairs is depicted in Table IV. No correlation was found between the changes of hormone receptors and HER2/neu (p>0.05) (15)(16)(17).…”

“…ReceivedMay 27, 2017 Revised July 15, 2017 Accepted July17, 2017 Timmer et al: Receptor Status Changes in Metastasized Breast Cancer…”

Local and Central Evaluation of HER2 Positivity and Clinical Outcome in Advanced Gastric and Gastroesophageal Cancer—Results from the AGMT GASTRIC-5 Registry

“…Intrapatient discordance rates between the primary tumor and metastases ranging from 2-24% [30][31][32] as well as intratumoral discordance rates [33,34] represent potential pitfalls of HER2 testing. Intratumoral HER2 expression heterogeneity can be found in up to 74% in early gastric cancer [35].…”

Surgical treatment of stomach cancer: possibilities of predicting survival rate at the present stage

“…Ободряюще было видеть, что существует такая система координат (VEGFR-p53+Her2-Ki-67+), где «антральные желудки» живут дольше, чем традиционно более «плохие» в плане отдаленной выживаемости больные, прооперированные по по- Îðèã³íàëüí³ äîñë³äaeåííÿ / Original Researches воду злокачественных эпителиальных опухолей тела и кардии. Методы расчета выживаемости могут быть использованы хирургами и химиотерапевтами для персонификации химиотерапевтического (Нer2/new, VEGFR) и индивидуализации хирургического метода лечения РЖ: инвазия в стенку, возраст больного, пораженные лимфоузлы, размер опухоли, степень злокачественности G и биоагрессивности р53 [3].…”