Salmon C, Conus F, Parent M-E, et al. - Via performing a population-based birth cohort study involving 400,611 individuals born in Québec, Canada, between 1970 and 1974, researchers examined the potential correlation of Bacillus Calmette-Guérin (BCG) vaccination and lymphoma, overall and separately for Hodgkin's (HL) and non-Hodgkin's lymphoma (NHL). Collectively, 178,335 people were BCG vaccinated, and 1,478 cases of lymphomas were identified. Of these, 922 and 421 were determined to be NHL and HL, respectively. No relationship was noted among BCG vaccination and either lymphoma (any type) or NHL, following adjustment. Non-proportional hazards were noted For HL. The risk of HL was raised in vaccinated individuals prior to the age of 18. Nevertheless, subsequent to 18 years of age, no correlation was noted. In all, prior to 18 years of age, BCG vaccination may raise the risk of HL, yet residual confounding cannot completely be eliminated. Moreover, the researchers suggested that these findings should be reproduced in other populations before firm conclusions can be made, given the advantages of BCG vaccination.