No, doctors and scientists don’t think PH is a tumor or cancer.
However, there is scientific evidence that the innermost lining cells (also known as endothelial cells) of the pulmonary arteries as well as cells within the wall of pulmonary arteries (smooth-muscle cells) may behave like tumor cells in patients with idiopathicPAH) IPAH. Indeed, these cells tend to intensely proliferate (multiply), just like cancer cells. This idea of tumor-like cells in IPAH is an area of ongoing research.