1. Targeting HER2 and Focusing on Patients With Gastric Cancer Jose Maria Vieitez, MD, PhD Assistant Professor of Oncology Department of Medical Oncology Hospital Universitario Central de Asturias Oviedo, Spain

2. Patient History and Presentation of Disease Personal history: –46-year-old woman –No other relevant history Family history: –Paternal grandfather: stomach cancer (51 years old) –Maternal aunt: breast cancer (45 years old) Disease presentation: February 2008 –Decreased appetite, early satiety, weight loss, and vomiting

3. Diagnosis: Stage IV Adenocarcinoma of Stomach Gastroscopy: ulcerated lesion in antrum –Biopsy: poorly differentiated, diffuse adenocarcinoma CT scan and abdominal echography –Liver lesions: 2.1 and 0.7 cm Tumor markers: elevated CEA, CA 19.9 and CA 72.4 CA = carbohydrate antigen; CEA = carcinoembryonic antigen; CT= computed tomography

4. Treatment Surgical resection: April 2008 –Partial gastrectomy and left anexectomy –Miliary lesions in peritoneum, lesions in liver and left ovary Systemic therapy: May 2008 –Cycle 1–6: cisplatin 70 mg/m 2, capecitabine 850 mg/m 2 D1–14 Based on the literature: HER2 testing requested –HER2 test result: IHC 3+ Cycle 7–27: trastuzumab 6 mg/kg/q3w + capecitabine HER2 = human epidermal growth factor receptor 2; IHC = immunohistochemistry

5. Tumor Assessment: Stable Disease at Cycle 3 Baseline: before treatment Cisplatin + capecitabine May 2008 Sep 2008 Imaging studies property of Jose Maria Vieitez, MD.

6. Tumor Assessment: Complete Response at Cycle 17 Trastuzumab + capecitabine Imaging studies property of Jose Maria Vieitez, MD.

7. Tumor Assessment: Disease Progression at Cycle 27 Trastuzumab + capecitabine Good quality of life and symptom relief Grade 1 anemia Grade 2 asthenia Grade 3 vomiting (responded to antiemetics) Time to progression: 17 months Jan 2010 Imaging studies property of Jose Maria Vieitez, MD.

8. Conclusions Treatment with trastuzumab is well tolerated, even in prolonged treatment Addition of trastuzumab in appropriately selected patients can increase efficacy, time to progression, and overall survival outside of clinical trial setting