PET is a functional imaging modality that has developed rapidly in recent years. Studies have shown that 18FDG-PET can provide important information for the differentiation of benign and malignant bone and soft tissue tumors, localization of lesions, evaluation of malignancy, determination of biopsy sites, assessment of treatment effects and prognosis, etc. PET has unparalleled advantages for the preoperative evaluation of bone and soft tissue tumors, especially for the evaluation of preoperative treatment efficacy. It has significant advantages in evaluating the efficacy of preoperative treatment. However, there is a lack of consensus on the value of 18FDG-PET in the evaluation of efficacy, which needs to be verified by scientific clinical studies, and only clinical case studies have been reported, and there is a lack of studies with a high level of evidence-based medicine. Bastiaannet et al. conducted a Meta-analysis on the use of PET in bone and soft tissue tumor diagnostic studies, and this systematic analysis concluded that PET can not only identify benign and malignant bone and soft tissue tumors, but also determine the malignancy of bone and soft tissue tumors. The investigators suggested that PET should be used as a routine clinical examination for diagnostic and efficacy evaluation. Franzius et al. concluded that FDG-PET is more accurate than bone scan in evaluating the efficacy of preoperative chemotherapy for bone tumors. It was further suggested that PET results could be an important indicator of patient prognosis, and a strong correlation between the degree of change in SUVmax values before and after chemotherapy and postoperative recurrence was found in these studies. The same conclusion has been obtained for other treatments evaluated by PET, including radiotherapy and limb isolation hyperthermic perfusion therapy. In this study, a systematic analysis of 10 studies was performed, and the results showed that FDG-PET can be used for preoperative assessment of treatment effects, and that the degree of change in SUVmax has a high correlation with postoperative tumor necrosis, with a specificity and accuracy of 0.82% and 0.61% for predicting tumor tissue necrosis ≥90% after chemotherapy for SUV2/SUV1≤0.5. The assessment of the efficacy of preoperative chemotherapy or other preoperative adjuvant treatments is important for the development of surgical approach and postoperative treatment plan. The commonly used preoperative chemotherapy assessment methods include bone scan, angiography and dynamic enhancement MRI, but these three examination methods are all indirect responses to the active degree of tumor components. However, these three methods are indirectly reflecting the active degree of tumor components. Compared with these methods, PET can directly reflect the metabolic activity of tumor cells. For example, Iagaru et al. hypothesized that the higher SUVmax after chemotherapy than before surgery in individual cases with >90% necrosis was due to the inflammatory response caused by certain chemotherapeutic agents, such as isocyclophosphamide. The maximum standardized uptake value (SUVmax) within the tumor tissue is generally currently used as an evaluation index, which may result in the SUVmax after chemotherapy responding to areas of chemotherapy-induced inflammation within the tumor tissue without accurately reflecting the changes in tumor composition. In this systematic review, 4 of the 87 cases (4.6%) with specific values were necrosis >90%, while SUVmax values were elevated after chemotherapy compared to before chemotherapy, and further studies are needed for the effect of post-chemotherapy inflammatory changes on the assessment of chemotherapy effects. PET for the evaluation of bone and soft tissue tumors preoperatively still lacks large clinical trials and definite conclusions, and systematic analysis would be beneficial to obtain more credible clinical evidence. With the popularity and development of evidence-based medicine in recent years, a large number of systematic evaluations based on randomized controlled trials have been completed and applied to guide clinical practice. In fact, as a research method, systematic evaluation incorporates clinical studies that can be either randomized controlled trials or non-randomized controlled trials. Moreover, systematic evaluation of non-randomized controlled trials has been conducted for almost 20 years. 100 literature on systematic evaluation were randomly searched in Medline by Egger et al. in 1998, 59 of which were subjected to Meta-analysis, and about 40% of these 59 literature were based on non-randomized controlled trials. This is because some important medical topics also have randomized controlled trials conducted. The application of systematic evaluation of nonrandomized controlled trials includes the evaluation of diagnostic trials. Care should be taken to conduct rigorous literature screening and quality control when conducting non-randomized controlled systematic reviews, because their results are susceptible to bias and confounding factors, and simply calculating the combined effect may lead to incorrect or even erroneous conclusions.