Trastuzumab With S-1 Plus Cisplatin in HER2-positive Advanced Gastric Cancer Without Measurable Lesions: OGSG 1202

Novel Biomarkers of Gastric Adenocarcinoma: Current Research and Future Perspectives

Simple Summary

Gastric cancer is characterized by poor survival rates despite surgery and chemotherapy. Current research focuses on biomarkers to improve diagnosis and prognosis, and to enable targeted treatment strategies. The aim of our review was to give an overview over the wide range of novel biomarkers in gastric cancer. These biomarkers are targets of a specific treatment, such as antibodies against human epidermal growth factor receptor 2. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are vascular endothelial growth factor, programmed cell death protein 1, and Claudin 18.2. There is a vast number of biomarkers based on DNA, RNA, and protein expression, as well as detection of circulating tumor cells and the immune tumor microenvironment.

Abstract

Overall survival of gastric cancer remains low, as patients are often diagnosed with advanced stage disease. In this review, we give an overview of current research on biomarkers in gastric cancer and their implementation in treatment strategies. The HER2-targeting trastuzumab is the first molecular targeted agent approved for gastric cancer treatment. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are VEGF and Claudin 18.2. Expression of MET has been shown to be a negative prognostic factor in gastric cancer. Targeting the PD-1/PD-L1 pathway with immune checkpoint inhibitors has proven efficacy in advanced gastric cancer. Recent technology advances allow the detection of circulating tumor cells that may be used as diagnostic and prognostic indicators and for therapy monitoring in gastric cancer patients. Prognostic molecular subtypes of gastric cancer have been identified using genomic data. In addition, transcriptome profiling has allowed a comprehensive characterization of the immune and stromal microenvironment in gastric cancer and development of novel risk scores. These prognostic and predictive markers highlight the rapidly evolving field of research in gastric cancer, promising improved treatment stratification and identification of molecular targets for individualized treatment in gastric cancer.

Docetaxel plus S-1 versus cisplatin plus S-1 in unresectable gastric cancer without measurable lesions: a randomized phase II trial (HERBIS-3)

BACKGROUND

Cisplatin plus S-1 (CS) is the standard first-line chemotherapy for advanced gastric cancer (AGC) in Japan. A previous phase III trial showed that docetaxel plus S-1 (DS) was effective for AGC without measurable lesions, but no studies have compared these two regimens.

METHODS

Eligible patients had unresectable or recurrent HER2-negative AGC without measurable lesions. Patients were randomized to DS (docetaxel 40 mg/m² on day 1, S-1 80-120 mg on days 1-14, every 3 weeks) or CS (cisplatin 60 mg/m² on day 8, S-1 80-120 mg on days 1-21, every 5 weeks). The primary endpoint was overall survival (OS).

RESULTS

All patients had unresectable primary disease. Sixty-one patients were randomly assigned to DS (n = 30) or CS (n = 31). One CS patient was ineligible due to HER2 positivity. The median number of cycles was 9.5 (range 2-49) with DS and 5.5 (range 1-10) with CS. There were no treatment-related deaths. The most common grade 3-4 non-hematological toxicity was fatigue (7% with DS, 13% with CS), followed by anorexia (3% with DS, 10% with CS) and diarrhea (3% with DS, 10% with CS). The 2-year OS rates were 43.3% with DS and 30.0% with CS (log-rank P = 0.113), with a hazard ratio of 0.617 (95% confidence interval 0.337-1.128), indicating non-inferiority of DS to CS with respect to OS (P < 0.001).

CONCLUSIONS

DS showed slightly but nonsignificantly less toxicity and higher efficacy than CS for AGC without measurable lesions. DS should be further investigated in phase III trials.

Treatment of esophageal cancer with multiple liver metastases: a case experience of sustained complete response

Esophageal squamous cell cancer with distant metastases has a poor prognosis. The metastatic sites usually involve the liver, bones, and lungs. Treatment of metastatic disease is essentially palliative and based on chemoradiotherapy. A 57-year-old man with a solitary metastatic mass of 82 × 58 mm in the left liver was treated on 19 October 2012. Irinotecan and cisplatin combination chemotherapy and nimotuzumab targeted therapy were administered. The liver metastatic mass was treated by stereotactic Gamma Knife radiosurgery. Complete remission of the primary disease and hepatic lesion was achieved, and no local or distant recurrence was found during the 7-year follow-up. Because extrahepatic lesions were ruled out and the local disease was completely locoregionally controlled, the use of stereotactic Gamma Knife radiosurgery to remove the hepatic lesion was justified and produced a reasonable outcome.

Emerging Targeted Therapies for HER2 Positive Gastric Cancer That Can Overcome Trastuzumab Resistance

Trastuzumab, a monoclonal antibody to human epidermal growth factor receptor 2 (HER2), has improved survival in patients with HER2-positive advanced gastric or gastroesophageal junction cancer (AGC). The inevitable development of resistance to trastuzumab remains a problem, however, with several treatment strategies that have proven effective in breast cancer having failed to show clinical benefit in AGC. In this review, we summarize the mechanisms underlying resistance to HER2-targeted therapy and outline past and current challenges in the treatment of HER2-positive AGC refractory to trastuzumab. We further describe novel agents such as HER2 antibody-drug conjugates that are under development and have shown promising antitumor activity in early studies.

S-1 plus apatinib as first-line palliative treatment for stage IVB gastroesophageal junction adenocarcinoma: A case report and review of the literature

RATIONALE

Apatinib has been proven to significantly prolong the survival of the patients with advanced chemotherapy-refractory gastric cancer. To date, studies on apatinib plus S-1 as first-line palliative therapy for metastatic gastroesophageal junction (GEJ) cancer are rare.

PATIENT CONCERNS

A 61-year-old female patient was admitted with dysphagia, significant loss of body weight, and poor performance status.

DIAGNOSES

Endoscopic biopsy revealed the diagnosis of poorly-differentiated GEJ adenocarcinoma, and the patient was clinically staged as T3NxM1G3 (IVB).

INTERVENTIONS

She had received 4 cycles of palliative therapy using oral apatinib (425 mg daily) plus S-1 (40 mg twice daily for 4 weeks, with a 2-week drug-free interval), followed by maintenance low-dose apatinib (250 mg daily) plus S-1 at the same dosage thereafter.

OUTCOMES

Her progression-free survival was nearly 5 months, and the overall survival was >11 months up to now. The adverse events were tolerable.

LESSONS

Apatinib plus S-1 might be an alternative option for late-stage GEJ cancer. However, high-quality trials are warranted before the recommendation of this therapeutic regimen.