In mainland France, the estimated number of new cases of HCL in 2018 was 304, including 243 in men and 61 in women. Key points: A cancer with a favorable prognosis, with a 5-year age-standardized net survival rate of 95% for individuals diagnosed between 2010 and 2015; 5-year net survival is relatively independent of age at diagnosis, slightly higher in younger individuals, ranging from 97% for a diagnosis at age 40 to 92% for a diagnosis at age 80; Net survival remains stable between 1 and 5 years.