Ghayumi et al. [8] found that the level of IFN-γ, a Th1 cell cytokine, was lower in the MPE that results from lung cancer than that associated with extrathoracic tumours, suggesting that the number of Th1 cytokines produced is closely related to the site of the tumour that is resulting in the production of MPE. Here, IFNG is linked to neoplasm.