Fibroblastic/ Myofibroblastic lesions constitute a significant number of soft tissue lesions encountered in the pediatric population. At the same time, these are one of the most enigmatic tumor categories posing an enormous diagnostic challenge which often leads to under/overtreatment. Generally, these lesions are grouped under a broad term of “fibroblastic proliferation” without any attempt towards their accurate subclassification. This book provides comprehensive coverage of these tumors to help the pathologist and clinicians in deciding their true biological potential and prognosis. New entities such as Lipofibromatosis, EWSR1-SMAD3-rearranged fibroblastic tumors, Primitive myxoid mesenchymal tumor of infancy have also been discussed in respective chapters. The book highlights the importance of fine-needle aspiration cytology in the workup of these lesions with the characteristic aspirate findings discussed in most of the cases. A sincere effort has been made to delve into the molecular aspect of each lesion with a detailed and updated pathogenetic account provided for each entity. The book also provides a glimpse of targeted therapy being used for these lesions.