Comment on: Omar NN, et al. Tumor potential in rat wounds after short- and long-term administration of platelet-rich plasma. J Biol Regul Homeost Agents. 2017 Oct-Dec;31(4):889-899. Platelet-Rich Plasma (PRP) is a promising concentrate. But are there any disadvantages or contraindications regarding its application? Is the use of PRP indicated in wounds of patients undergoing resection for cancer. The presence of growth factors could promote tumor proliferation and recurrence. It is of the utmost importance to recognize any possible contraindication before we call it safe. The role of PRP in tumorigenicity deserves further experimental investigation and large-scale prospective randomized clinical trials.