Ning Li et al., at Chinese Academy of Medical Sciences and Peking Union Medical College, China, provides a comprehensive review on the challenges and opportunities in the field of rare tumor research and management. Despite advances in sequencing technologies and therapies extending the lives of many cancer patients, rare tumors remain a significant challenge in modern oncology.
The definition of rare tumors is initially explored, with a focus on incidence rates rather than prevalence, due to the genetic, environmental, and lifestyle variations that lead to differences in tumor incidence and molecular profiles across populations. In the United States, rare tumors are defined by the FDA and National Cancer Institute as those with an incidence of less than 15 per 100,000 people per year. In Europe, the threshold is set at 6 per 100,000 by the European Society for Medical Oncology and European Medicines Agency.
In China, a rate of 2.5 per 100,000 per year is used to define rare tumors after a comprehensive analysis of epidemiological data and availability of standardized treatments. The article emphasizes the value of rare tumor research, which has led to significant biological and medical discoveries, such as the study of retinoblastoma leading to the identification of the RB1 gene and the double-hit hypothesis.
However, the understanding of rare tumors is advancing slowly due to limited patient numbers, lack of experience in medical centers, and reluctance from the pharmaceuti.