PCSK4 and neoplasm: Similarly, a study by Kawai et al., on a group of patients with a solitary fibrous tumor, showed that imbalanced expression of IGF‐II and PCSK4 in tumor tissue was associated with elevated circulating levels of big IGF‐II and the syndrome of NICTH.44 NICTH represents an extreme case of excessive production of high MW IGF‐II, often by a large solid tumor, leading to an enormous insulin‐like activity in the body.