Oncogenetic Panel and Integrated Clinical Data Registry Study for Wild Type Gastrointestinal Stromal Tumor Patients

Cancer is the most common cause of death in Taiwan since 1982. The incidence of cancer is increasing worldwide, including Taiwan. Cancers in early stage can usually treated with surgery with a good prognosis. However, the prognosis for recurrent, locally advanced or metastatic cancers are poor with a shorter survival. Systemic treatments are usually indicated for these patients. Chemotherapy is the main stay for advanced cancer patients. However, the advances in the understanding of cancer biology and identification of targeted therapeutics not only increase the treatment strategies of cancer but also improves the survival and quality of life of the cancer patients. There are more and more molecularly targeted therapy developed and approved for the treatment of advanced cancer patients currently, which makes the beginning of precision cancer medicine. There are more and more treatments can be used based on the genetic aberrations of the cancers. Because one cancer type may habor various genetic aberrations, it is not enough to check only one or a few genes for a patient to choose the adequate treatment. Because the advance in multiplex genomic test, several NGS-based cancer-associated genetic panel test (oncopanel) have been developed and used to identify the genetic alterations in each patient, particularly the actionable genes. Large scale checks of oncopanel have been executed in US. The study showed the genetic alterations in various cancer types and 11% of the patients had further molecular targeted therapy based on the result of the oncopanel test. The similar program was done in Japan. Moreover, the oncopanel test have been implicated in their clinical practice and the cost was reimbursed by the government in Japan and Korea recently. The precision medicine and such personalized treatment is the trend for cancer treatment. The trend of such treatment patterns is also observed in Taiwan. The genetic background for cancer treatment may also be different among different areas and races. There is lack of Taiwanese data of genetic alterations in cancer patients. To understand the landscape of genetic aberrations of cancer in Taiwan, large scale survey of the cancer patients is indicated. In this pilot study, the investigators want to evaluate the landscape of genetic aberrations in cancer patients via oncopaenl test and collect the clinical data of the patients. The result of the oncopanel test will be returned to patient and their attending physician for reference of their further treatment. In addition, the investigators want to correlate the clinical outcome with the genetic aberrations of the cancer patients in Taiwan. Gastrointestinal stromal tumor (GIST) is a rare cancer compared with the other solid tumors. C-KIT or PDGFRA mutation is found in approximately 85-90% of GISTs. Imatinib, a tyrosine kinase inhibitor targeting c-KIT, has been used to treat advanced GIST successfully since 2000. However, resistance to imatinib may develop either via secondary mutation of c-KIT or primary resistance to those with wild type c-KIT and PDGFRA. Although sunitinib and regorafenib have been approved as second and third line of treatment for advanced GIST, the progression free survival were only 6.8 and 4.8 months, respectively. The genetic landscape of GIST with wild type c-KIT and PDGFRA was less studied. In the current study, wthe investigators want to focus on the GISTs with wild type c-KIT and PDGFRA to perform the NGS oncopanel for these patients. Then the investigators can understand the genetic aberrations of these patients (wild type GIST) and help for searching the potential treatment targets to the participants.

Inclusion criteria

• Pathologically confirmed GIST.
• The tumors can be resected, unresectable, recurrent or metastatic and the patients had ever received, are receiving or will receive systemic treatment (adjuvant, neoadjuvant or salvage TKI or other targeted agents)
• The tumors were tested for wild type c-KIT and PDGFRA.
• There are archived tumor samples available or the patients agree to do tumor biopsy for oncopanel test if there is no tumor sample or not enough tumor sample available.
• The patients who are systemic treatment naïve or have received prior systemic treatment are all eligible.
• Age - the legal age.
• Life expectancy greater than 6 months
• Capable of understanding and complying with the protocol requirements and signed informed consent.

Exclusion criteria

• Patients will be excluded from the study if they meet any of the following criteria:

• Inability and unwillingness to give informed consent
• Patients do not agree to provide archived tumor samples and blood samples or they do not agree to do tumor biopsy when archived tumor samples are not available.
• Patients refused for collection of clinical data and follow up.
• Mental status is not fit for further treatment or data collection.