The relationship between brain metastasis and HER2 expression status in gastric cancer.

BACKGROUND: Brain metastasis (BM) in gastric cancer (GC) is underestimated, and human epidermal growth factor receptor 2 (HER2) overexpression is a durable poor prognostic factor. We explored the relationship between the two and made a survival analysis. METHODS: HER2 expression and BM status were collected from GC patients who were diagnosed between December 2009 and May 2021. We collected GC patients diagnosed between 2010 and 2016 from the SEER database. The primary endpoint was survival from the diagnosis of BM. Multivariable logistic regression was used to determine potential risk factors of BM at diagnosis in SEER database. Survival analysis was performed using the Kaplan-Meier method. RESULT: There were 513 HER2-positive GC patients, including 16 (3.1%) with BM. Among 38 brain metastasis GC patients we collected, 16 (42.1%) patients were HER2 positive. We collected 34,199 GC patients from the SEER database and there were 260 (0.76%) patients with BM at diagnosis. GC patients that are male, white, of younger age, with primary lesions located in the proximal stomach or with distant lymph nodes, liver, bone, or lung metastasis are more likely to develop BM. The median overall survival time from diagnosis of BM was 12.73 months, and the survival time from brain metastasis of HER2-positive patients was numerically shorter, though the difference was not significant (5.30 months vs.16.13 months, P = 0.28.) CONCLUSION: The incidence of BM in patients with HER2-positive gastric cancer is 4.08 times higher than that in general patients. The median overall survival time from BM is shorter for HER2-positive patients.

Gastric cancer with brain metastasis and the role of human epidermal growth factor 2 status.

Central nervous system (CNS) metastases from cancers of the gastrointestinal tract (GIT) are rare, and occur in 0.16-0.69% of patients with gastric or gastro-esophageal (GE) junction cancer. Overexpression of the human epidermal growth factor 2 (HER-2) is associated with poor prognosis in the absence of HER-2-targeted therapy, and with an increased incidence of CNS metastases in patients with breast cancer. The role of HER-2 overexpression in CNS metastases is not well known in gastric adenocarcinoma. The purpose of the present retrospective study was to assess the incidence of CNS metastases and to evaluate the associations between the CNS and HER-2 status in a series of consecutive patients with gastric or GE junction cancer. Between 2007 and 2013, 300 patients with gastric cancer (GC) or gastroesophageal junction, were admitted to Piacenza General Hospital, Italy. These cases were retrospectively analyzed to evaluate CNS metastases. The metastases were diagnosed with imaging techniques performed on symptomatic patients. Gastric histological samples of patients with CNS metastases were reviewed and tested for HER-2. A total of 7 of the 300 patients (2.33%) with GC were observed to have CNS metastases and 6 (85.71%) had HER-2 positive disease. These patients exhibited a poor prognosis with a median overall survival rate of 4.1 months (range, 2.1-6.6 months). These results suggested there may be CNS recurrence susceptibility in patients with HER-2 positive GC. To the best of our knowledge, this is the first report that associates CNS metastases and HER-2 status in gastric or GE junction cancer.