Traditionally, cancer has been diagnosed through clinical symptoms, clinical imaging, biochemical tests, tumor histopathological analysis, and the increasingly popular molecular diagnosis. Molecular analysis of tumor tissue samples has emerged as a potential method of cancer classification. These tests must be performed with the help of tumor tissues, which need to be obtained through local tissue biopsy or surgery to take samples and sections from tumor samples. These methods can cause trauma and psychological concerns to patients on the one hand, and at the same time, biopsy is often not possible due to the location of the tumor, such as deep tissue or near important organs, or the patient’s physical condition does not allow it. Therefore, in recent years, blood-based “liquid biopsy” has gradually been emphasized, such as the current free DNA and circulating tumor DNA based tests have also played a role in tumor diagnosis. However, these methods are not ideal in terms of sensitivity and specificity, and the search for new diagnostic methods is still an urgent task. Recently Myron G wrote in the world’s top journal CANCER CELL that sequencing tests using platelet RNA can distinguish cancer patients from healthy individuals with 96% accuracy, as well as six primary tumor types with 71% accuracy, and identify genetic alterations found in several tumors. Ahead of other liquid biopsies, RNA sequencing based on TEPs can provide an accurate diagnosis of cancer by identifying the site of the primary tumor. Myron G and his research team, drew blood from 283 subjects, isolated platelets, extracted platelet RNA, and amplified the RNA for subsequent sequencing. The results showed that RNA sequencing based on TEPs was able to distinguish between 228 who were tumor patients (both localized and metastatic tumors) and 55 who were healthy individuals, with an accuracy of 96%. It could also distinguish 6 different types of tumors with an accuracy rate of 71%. RNA sequencing based on TEPs enabled accurate differentiation of tumors that were her2 positive, KRAS gene mutated, epidermal growth factor receptor or PIK3CA positive. The results suggest that tumor platelet mRNA provides a valuable platform for pan-cancer detection, tumor classification and tumor mutation gene diagnosis, and facilitates the development of blood-based liquid biopsies. Why platelet RNA testing can accurately diagnose malignancies? Tumor platelet testing can be a blood-based cancer diagnostic method. Why can platelets play such a major role? It turns out that platelets, the second most abundant cell type in the blood, are produced by megakaryocytes in the bone marrow hematopoietic tissue and are present in the peripheral circulation to play a role in hemostasis and wound healing in the body. Due to morphological and functional reasons, platelets have become the central molecule in systemic and local responses during tumor growth. In vitro and in vivo experiments have demonstrated that tumor cells can transfer (mutated) RNA into platelets. Some researchers have identified cancer-related RNA biomarkers EGFRvIII , PCA3 , etc. from platelets drawn from patients with glioma and prostate cancer. Tumor-derived RNA biomarkers contained in platelets can be detected by a method called TEPs, which makes it a potential diagnostic method for cancer diagnosis. In this study, Myron G et al. describe the distribution of platelet mRNA in patients with various cancers and in healthy humans, and evaluate whether sequencing based on TEPs can be used as a method for cancer grading and cancer diagnostic aid. With the progress of tumor molecular biology research, the study of platelet-based RNA sequencing and its biological indicators will potentially provide a series of convenient, rapid, specific, non-invasive or minimally invasive molecular biology tests for early diagnosis, prognosis determination and follow-up of clinical tumors, which will also benefit the majority of tumor patients.