Recent observations on mesenchymal tumours in adults and children

Recognition of the types and characteristics of mesenchymal tumours is important, since each type has biological features peculiar to itself that govern its growth and behaviour and it is essential to know these if treatment is to be effectual. Because many differentiated cell types are capable of acting as facultative fibroblasts, histological diagnosis is often in error. It has been found that no matter how bizarre a tumour may appear, if explanted in vitro, the cells will betray their true nature. By this means the various mesenchymal tumour types have been classified, many examples collected and followed up and their biological potentialities recorded. In more recent studies these uncommon tumours in children have been studied and many of them found to be less malignant than in adults. New varieties of mesenchymal tumours have been discovered in recent years, such as pseudosarcomatous fasciitis, elastofibroma dorsi, and bizarre variants of smooth muscle tumour.