Real-World Long-Term Survival for Different Types of Cancers in the United States

Background: Long-term survival is an important endpoint that is rarely assessed due to the unfeasibility of long-term follow-up. In this study, we are exploring real-world data on long-term survival using historical records from Surveillance, Epidemiology, and End Results (SEER) database. Besides the reporting of 5-year relative survival, we have also analyzed 10- and 20-year survival for different types of cancers. Survival trends as a function of time, age at diagnosis, and tumor type were also reviewed. Methods: SEER*Stat version 8.3.6.1 was used for data acquisition from SEER 9 Regs (Nov 2019 Submission) database. Data of patients diagnosed between 1975 and 2014 were retrieved and included in the analysis. Results: For patients diagnosed with any malignant disease (n = 4,412,024), the median overall survival (66 months) showed a significant increase over time from 1975-2014 (p < 0.001). Twenty-, ten-, and five-year survival rates were all higher in solid tumors compared with hematological malignancies (50.7% versus 37.7%, 57% versus 47%, and 62.2% versus 56.9%, respectively). Highest 20-year relative survival was observed in thyroid cancer (95.2%), germ cell and trophoblastic neoplasms (90.3%), melanoma (86.8%), and Wilms’ tumor (86.2%). Conclusions: Long-term follow-up data were suggestive of high 20-year relative survival for most tumors. Relative survival showed an improving trend over time. Hematological malignancies, even though most of them are being perceived as curable, had lower long-term survival than solid tumors.