Objective To analyze the incidence and risk factors of pelvic insufficiency fractures (PIF) in patients with cervical cancer who received pelvic intensity-modulated radiotherapy.Methods This study a retrospective review of all patients was performed with cervical cancer who received pelvic intensity-modulated radiotherapy at our institution from November 2013 to December 2015,and the incidence and risk factors of insufficiency fractures were analyzed.Results Among the 104 patients,16 (with a total of 31 lesions) were diagnosed with pelvic insufficiency fracture.The occurrence rate of pelvic insufficiency was 15.4％.Ten patients (62.5％) had multiple fractures and five patients (31％) complained of pain.All patients' pain was relieved by rest or analgesic drugs.Insufficiency fractures were detected at a median of 6.5 months (range 1-16) from radiotherapy completion.The distribution of PIFs was followed:sacral had 16 cases (51.6％),sacroiliac joint had 7 cases (22.6％),iliac had 6 cases (19.4％),femoral head had 1 case (3.2％) and pubis had 1 case (3.2％).Univariate analysis and multiple analysis showed that postmenopausal status and low body weight (≤55 kg) were thought to be risk factors for PIF(P ＜ 0.05).Subgroup analysis also confirmed that postmenopausal status was a risk factor for PIF (P ＜ 0.05) in postoperative cervical cancer patients after pelvic intensity-modulated radiation therapy.Conclusions Cervical cancer patients with menopausal status and low body weight (≤55 kg) are at some risk for the development of PIF after pelvic intensity-modulated radiotherapy.

Objective To analyze the clinical efficacy and prognosis of stereotactic body radiation therapy (SBRT) for pulmonary oligometastases.Methods Medical records of 104 patients with SBRT for pulmonary oligometastases in our hospital between 2012 and 2018 were retrospectively reviewed.SBRT was performed by intensity modulated radiation therapy (IMRT) technique before December 2015,and by helical tomotherapy (HT) technique in others.The local control (LC),progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.Cox-regression was used for univariate analyses and multivariate analyses.The radiotherapy-related adverse events were evaluated by NCICTCAE V4.0.Results The 1-,2-and 3-year LC rates were 86.6％,75.9％ and 72.3％,respectively.The 1-,2-and 3-year PFS rates were 40.9％,28.4％ and 22.1％,respectively.The 1-,2-and 3-year OS rates were 75.9％,53.2％ and 43.53％,respectively.The median OS time was 26.6 months.Multivariate analyses showed that the pathologic type of primary tumor,the volume of lung oligometastases and the carcino-embryonic antigen (CEA) level before SBRT were the independent prognostic factors of LC (x2 =28.66,P＜0.05).The way of tumor progression after SBRT was the independent prognostic factor of OS (x2=40.01,P＜0.05).Meanwhile,there were no significant differences in the LC and OS between HTSBRT and IMRT-SBRT.Radiation pneumonitis was the major adverse event of SBRT (n =25,24.04％).Less than 7％ patients experienced grade 2 and above radiation pneumonitis.Conclusions SBRT shows high local control rates and tolerable adverse events in the treatment of pulmonary oligometastases.There were no significant differences in the clinical efficacy and adverse events between HT-SBRT and IMRT-SBRT,which means they are all suitable for clinical application.