Incidence Of Pelvic Insufficiency Fracture Research Articles

Pelvic insufficiency fractures in locally advanced cervical cancer: the diagnostic yield of post-treatment MRI in a tertiary centre.

To assess the incidence of pelvic insufficiency fractures (PIFs) after concurrent chemoradiotherapy (CCRT) in patients with locally advanced cervical cancer (LACC), their time of onset and risk factors. We also analysed the inter-observer agreement between gynaecologic radiologists (GYN readers) and radiologists expert in musculoskeletal imaging (MSK reader) in detecting PIFs in our tertiary care centre. Patients with confirmed LACC who underwent concurrent chemoradiation (CCRT) at our institution from June 2019 to November 2022 were retrospectively included. These patients underwent follow-up pelvic MRI every 3-6months after CCRT. Cohen's kappa statistics was employed to assess the inter-observer agreement between GYN and MSK readers.Logistic regression analysis was performed calculating odds ratios (OR) to identify risk factors for PIFs, such as age, body mass index (BMI), diabetes, smoking, hypertension, renal function and tumour size. Eighty-seven patients were included. PIFs were diagnosed in 21/87 (24.1%) patients with a median onset time of 7.4months from the end of EBRT. Among risk factors, age was statistically associated with PIFs (OR = 1.057, 95% CI: 1.005-1.118, p=0.033) with median age in the fracture group of 61.1years (range: 52.0-71.5) and 53.8years (range: 43.8-63.3). BMI was a significant predictor of PIFs (OR = 1.134; 95% CI: 1.013-1.285; p=0.027), with a higher median BMI among patients with PIFs (26.5; range: 21.5-31.2) compared to non-fractured patients (23.1; range: 20.2-25.1). Also patients with reduced renal function (eGFR<60mL/min) had 3.437 times higher odds of experiencing fractures compared to those with normal eGFR. The GYN readers correctly identified PIFs in 2/21 cases and agreed with the MSK reader in 68/87 cases. The interobserver agreement was poor to fair (K=0.138; 95% CI: 0-0.311). PIFs are a common complication of CCRT. Their identification on post-CCRT MRI may decrease the need for further targeted investigations and invasive treatments.

Insights into pelvic insufficiency fracture following pelvic radiotherapy for cervical cancer: a comparative review

BackgroundRadiotherapy (RT)-induced pelvic insufficiency fractures (PIF) are prevalent in patients with cervical cancer. Inconclusive studies on PIF after cervical irradiation create uncertainty. This review examined PIF after RT in cervical patients, including its pathobiology, likely locations of fractures, incidence, clinical symptoms, and predisposing factors. We further discussed study limitations and therapeutic possibilities of PIF.MethodsThe following online resources were searched for relevant articles: Google Scholar and PubMed. The keywords ‘pelvic insufficiency fractures’, ‘cervical carcinoma’ and ‘cervical cancer’, as well as ‘chemoradiotherapy’, ‘chemoradiation’, and ‘radiotherapy’, were some of the terms that were used during the search.ResultsPatients with PIF report pelvic pain after radiation treatment for cervical cancer; the incidence of PIF ranges from 1.7 to 45.2%. Evidence also supports that among all patients treated with pelvic radiation, those who experienced pelvic insufficiency fractures invariably had at least one sacral fracture, making it the most frequently fractured bone in the body. Menopausal status, weight, BMI, age, and treatments and diagnosis modalities can influence PIF during radiotherapy.ConclusionsIn conclusion, our comparative review of the literature highlights significant heterogeneity in various aspects of PIF following radiation for patients with cervical cancer. This diversity encompasses prevalence rates, associated risk factors, symptoms, severity, diagnosis methods, preventive interventions, and follow-up periods. Such diversity underscores the complexity of PIF in this population and emphasizes the critical need for further research to elucidate optimal management strategies and improve patient outcomes.

Pelvic insufficiency fractures and pelvic bone metastases after neoadjuvant (chemo)radiotherapy for rectal cancer

Background: Pelvic insufficiency fractures (PIFs) are a late complication of radiotherapy for pelvic malignancies. We evaluated the incidence, radiologic findings, clinical course, and outcome of PIFs in patients treated with neoadjuvant (chemo)radiotherapy ((C)RT) for rectal cancer. Material and methods: Data of patients diagnosed with rectal cancer from a large teaching hospital treated from 2002 to 2012 were extracted from the Dutch Cancer Registry. All hospital records were reviewed for the diagnosis of PIFs or pelvic bone metastases. An expert radiologist reassessed all imaging procedures of the lower back, abdomen, and pelvis. Results: A total of 513 rectal cancer patients were identified of whom 300 patients (58.5%) were treated with neoadjuvant (C)RT (long- vs. short-course radiotherapy: 91 patients [17.7%] vs. 209 [40.7%], respectively). Twelve PIFs were diagnosed initially according to hospital records and imaging reports of all 513 patients. These 12 patients were treated with neoadjuvant (C)RT. After reassessment of all pelvic imaging procedures done in this patient group (432 patients (84.2%)), 20 additional PIFs were detected in patients treated with neoadjuvant (C)RT, resulting in a 10.7% PIF rate in irradiated patients. One PIF was detected in the group of patients not treated with neoadjuvant (C)RT for rectal cancer. This patient had palliative radiotherapy for prostate cancer and is left out of the analysis. Median follow-up time of 32 PIF patients was 49 months. Median time between start of neoadjuvant (C)RT and diagnosis of PIF was 17 months (IQR 9–28). Overall median survival for patients with PIF was 63.5 months (IQR 44–120). Conclusion: PIFs are a relatively common late complication of neoadjuvant (C)RT for rectal cancer but are often missed or misdiagnosed as pelvic bone metastases. The differentiation of PIFs from pelvic bone metastases is important because of a different treatment and disease outcome.

PET/MRI is useful for early detection of pelvic insufficiency fractures after radiotherapy for cervical cancer.

Radiotherapy (RT) is used to manage cervical cancer, and pelvic insufficiency fracture (PIF) is known as a late complication of RT. The present study identified risk factors for PIF after radiotherapy for cervical cancer, and investigated its incidence rate. It also considered the usefulness of positron emission tomography/magnetic resonance imaging (PET/MRI) in PIF diagnosis. A total of 149 patients with cervical cancer who received definitive or adjuvant RT with/without concurrent chemotherapy between January 2013 and December 2018 were investigated in the present study and followed up for more than one month after RT at Kobe University Hospital. The median follow-up period was 32 months (range, 1–87 months), and the median age of all patients was 66 years (age range, 34–90 years). Computed tomography (CT), MRI, PET/CT or PET/MRI were used for image examination. Among the 149 patients, 31 (20.8%) developed PIF. The median age of these patients was 69 years (age range, 44–87 years). Univariate analysis using the log-rank test demonstrated that age (≥60 years) was significantly associated with PIF. The median maximum standardized uptake value of PIF sites on PET/CT was 4.32 (range, 3.04–4.81), and that on PET/MRI was 3.97 (range, 1.21–5.96) (P=0.162). Notably, the detection time of PIF by PET/MRI was significantly earlier compared with PET/CT (P<0.05). The incidence of PIF after RT for cervical cancer was 20.8%, and age was significantly associated with risk factors for such fractures. Taken together, these results suggest that PET/MRI, which offers the advantage of decreased radiation exposure to the patient, is useful for diagnosing PIF and can detect it earlier than PET/CT imaging.

Pelvic Insufficiency Fractures in Cervical Cancer After Radiation Therapy: A Meta-Analysis and Review.

The aim of the study was to estimate the prevalence of pelvic insufficiency fractures (PIFs) after radiation therapy (RT) in patients with cervical cancer. A total of 3,633 patients from 15 cohort studies were included. Proportion meta-analysis was performed to estimate prevalence and subgroup analysis was performed according to imaging modalities for diagnosis of PIF. For continuous variables (age and length of follow-up), meta-regression analysis was performed. Pooled prevalence estimate of PIF was 14% (95% CI=10-19). Incidence of PIF was higher in studies that used MRI as a diagnostic tool (17%, 95% CI=12-22) than non-MRI (8%, 95% CI=2-14). In meta-regression, we found a significant association of prevalence of PIF with age (p=0.021) but not with length of follow-up (p=0.118). PIF after RT in patients with cervical cancer is not rare. Physicians need to pay attention to PIFs, especially in patients with high-risk factors for osteoporotic fracture.

Pelvic insufficiency fractures following carbon-ion radiotherapy for uterine carcinomas

There is growing evidence on the role of carbon-ion radiotherapy (C-ion RT) for gynaecological tumours. Pelvic insufficiency fracture (PIF) decreases the quality of life after photon beam radiotherapy (RT). However, there is little information on PIF after C-ion RT. This study retrospectively assessed incidence of PIF after C-ion RT for uterine carcinomas (UCs) and the associations of clinical and dosimetric parameters with PIF incidence. We performed a pooled analysis of 102 patients with UCs who underwent definitive C-ion RT alone and were followed up for >6months without any additional RT in the pelvic region. PIF occurrence was surveyed using magnetic resonance imaging and/or computed tomography. Associations of clinical and dosimetric parameters with PIF incidence were analysed. The 2- and 5-year actuarial incidences of ≥grade 1 PIF in all pelvic regions were 22.3% and 42.4%, respectively. The most frequent site of involvement was the sacrum. Log-rank tests showed that higher volumes receiving >10Gy (relative biological effectiveness) (V10), V20, V30, and V40, body mass index (BMI) under 18.5, and current smoking were associated with increased incidence of ≥grade 1 PIF in the sacrum. We clarified the actuarial incidence of PIF after C-ion RT for UCs. Higher V10, V20, V30, V40, D50%, Dmean, current smoking, BMI <18.5, and using the anterior-posterior direction in whole pelvic irradiation were associated with higher incidences of PIF in the sacrum. The present results may lead to further improvement of C-ion RT for UCs.

An easy way to determine bone mineral density and predict pelvic insufficiency fractures in patients treated with radiotherapy for cervical cancer

PurposeThe aim of this study was to investigate whether bone mineral density (BMD) as measured in planning computed tomographies (CTs) by a new method is a risk factor for pelvic insufficiency fractures (PIF) after radio(chemo)therapy (R(C)T) for cervical cancer.Methods62 patients with cervical cancer who received definitive or adjuvant radio(chemo)therapy between 2013 and 2017 were reviewed. The PIF were detected on follow-up magntic resonance imaging (MRI). The MRI of the PIF patients was registered to the planning CT and the PIF contoured. On the contralateral side of the fracture, a mirrored structure of the fracture was generated (mPIF). For the whole sacral bone, three lumbar vertebrae, the first and second sacral vertebrae, and the PIF, we analyzed the BMD (mg/cm3), V50Gy, Dmean, and Dmax.ResultsOut of 62 patients, 6 (9.7%) had a fracture. Two out of the 6 patients had a bilateral fracture with only one of them being symptomatic. PIF patients showed a significantly lower BMD in the sacral and the lumbar vertebrae (p < 0.05). The BMD of the contoured PIF, however, when comparing to the mPIF, did not reach significance (p < 0.49). The difference of the V50Gy of the sacrum in the PIF group compared to the other (OTH) patients, i.e. those without PIF, did not reach significance.ConclusionThe dose does not seem to have a relevant impact on the incidence of PIF in our patients. One of the predisposing factors for developing PIF after radiotherapy seems to be the low BMD. We presented an easy method to assess the BMD in planning CTs.

Pelvic Insufficiency Fractures After External Beam Radiation Therapy for Gynecologic Cancers: A Meta-analysis and Meta-regression of 3929 Patients

To estimate the overall rate, symptomatic proportion, and most common sites of pelvic insufficiency fracture (PIF) after external beam radiation therapy for gynecologic cancers based on posttreatment computed tomography, magnetic resonance imaging, positron emission tomography, or bone scintigraphy. A systematic search of databases (PubMed and EMBASE) was performed (CRD42019125679). The pooled summary of overall PIF and the proportion of symptomatic cases were calculated using the random-effects model weighted by the inverse variance. A multivariate meta-regression was performed to evaluate potential sources of heterogeneity regarding PIF fractures. Twenty-one studies met the inclusion criteria (total 3929 patients). Five hundred four patients developed PIF, translating to an overall rate of 14% (95% confidence interval, 10%-18%, based on 21 studies). Among these cases with PIF, the proportion of symptomatic patients was 61% (95% confidence interval, 52%-69%, based on 14 studies). The total number of PIFs was 704 (mean, 1.72 PIFs per each patient to develop PIF, based on 14 studies). More recent series (P = .0074) and the use of intensity modulated radiation therapy (P = .0299) were associated with lower fracture rates. The most common fracture sites were sacroiliac joint (39.7%), body of the sacrum (33.9%), pubis (13%), lumbar vertebra (7%), iliac bone (2.8%), acetabulum (2.1%), and femoral head/neck (1.5%). The median time to fracture was 7.1 to 19 months after radiation therapy. The incidence of PIF after radiation therapy for gynecologic cancers is high (14%), with the majority affecting the sacral bone or joint (73.6%), although this risk appears to be lower with intensity modulated radiation therapy. Posttreatment bone surveillance is warranted in this population because nearly 40% of patients were asymptomatic at the time of PIF diagnosis.

Pelvic insufficiency fractures, dose volume parameters and plan optimization after radiotherapy for rectal cancer

Patients treated with CRT for primary rectal cancer underwent a 3-year pelvic MRI for identification of PIFs. Bone structures were retrospectively delineated, and DVHs were re-calculated. Comparative planning was done with 2 (original) and 3 arc VMAT, fixed field IMRT and PBT plans. 27 patients (18 men, mean age 64 years) were included and PIFs were identified in 9 (33%), most (n = 6) had multiple fracture sites. In general, patients with PIFs received higher doses to pelvic bones, and V30 Gy to the sacroiliac joint was non-significantly higher in patients with PIF 68.5% (60.1-69.3 IQR) vs. 56% (54.1-66.6 IQR), p = 0.064. Comparative planning showed that especially 3 arc VMAT and proton beam therapy could be optimized for bone. Patients, treated with VMAT based CRT for rectal cancer, have high rates of PIFs after 3 years. Patients with PIFs tended to have received higher doses to sacroiliac joints. Comparative planning demonstrated most pronounced bone sparing capacity of 3 arc VMAT and with PBT having the potential to further lower doses. These results should be validated in larger and preferably prospective cohorts.

Current research progress on pelvic insufficiency fractures after radiotherapy for pelvic neoplasms

Pelvic insufficiency fractures (PIF) is a vital complication after radiotherapy for pelvic neoplasms. It often leads to intractable pain and limited activity and is likely to be misdiagnosed as bone metastases and improperly treated. MRI is a common method for the diagnosis and differential diagnosis of PIF. The optimal approach to prevent PIF is to correctly identify the high-risk population and provide drug intervention when necessary. The low bone density state serves as a pivotal predictor at the beginning of radiotherapy. Reasonable selection of irradiation dose in pelvic lymphatic drainage area and minimizing the dose of pelvic bone probably reduce the incidence of PIF after radiotherapy. Key words: Pelvic neoplasm/radiation therapy; Pelvic insufficiency fractures; Sacral bone

Insufficiency fractures in postmenopausal gynaecological patients receiving pelvic radiotherapy treatment – can we prevent them by optimising bone health?

To reduce the incidence of pelvic insufficiency fractures in women who have undergone gynaecological radiotherapy by producing a tool to help clinicians optimise bone health. We conducted a literature review of insufficiency fractures, the relationship of these with radiotherapy and treatment of

Pelvic Insufficiency Fracture Incidence in Patients Treated With Intensity-Modulated Radiation Therapy for Gynecological or Anal Cancer

To summarize results for pelvic insufficiency fracture (PIF) in patients with anal or gynecological cancer treated with pelvic intensity modulated radiation therapy (IMRT). The clinical and morphological (CT and / or pelvic MRI) characteristics of patients treated by IMRT at our institution, between 2007 and 2014 were analyzed. The global incidence of PIF after external beam radiotherapy and the impact of tumour site (gynaecological or anal cancer) were determined. A dosimetric study was then performed to compare patients with and without pelvic fracture. Three hundred forty-one patients were treated by IMRT for gynaecological or anal cancer between 2007 and 2014. Fifteen patients experienced at least one pelvic fracture after external beam radiotherapy, corresponding to an overall incidence of 4.4%. Age and menopausal status were correlated with an increased fracture risk (p=0.03 and p <0.0001, respectively). The site of the primary tumour (gynaecological or anal canal) was not associated with an excess fracture risk. The median maximum dose received at the fracture site was 50.3 Gy (range: 40.8-68.4). The incidence of pelvic fracture after IMRT is low, but is higher after the age of 50 and in postmenopausal patients. Pretreatment evaluation of bone density by bone densitometry and phosphorus-calcium assessment could be useful prior to the management of these patients.

Risk Factors for Pelvic Insufficiency Fractures in Locally Advanced Cervical Cancer Following Intensity Modulated Radiation Therapy

To investigate the incidence of and risk factors for pelvic insufficiency fracture (PIF) after definitive chemoradiation therapy for locally advanced cervical cancer (LACC). We analyzed 101 patients with LACC treated from 2008-2014. Patients received weekly cisplatin and underwent external beam radiation therapy with 45Gy in 25 fractions (node-negative patients) or 50Gy in 25 fractions with a simultaneous integrated boost of 60Gy in 30 fractions (node-positive patients).Pulsed dose rate magnetic resonance imaging guided adaptive brachytherapy was given in addition. Follow-up magnetic resonance imaging was performed routinely at 3 and 12months after the end of treatment or based on clinical indication. PIF was defined as a fracture line with or without sclerotic changes in the pelvic bones. D50% and V55Gy were calculated for the os sacrum and jointly for the os ileum and pubis.Patient- and treatment-related factors including dose were analyzed for correlation with PIF. The median follow-up period was 25months. The median age was 50years. In 20 patients (20%), a median of 2 PIFs (range, 1-3 PIFs) were diagnosed; half were asymptomatic. The majority of the fractures were located in the sacrum (77%). Age was a significant risk factor (P<.001), and the incidence of PIF was 4% and 37% in patients aged ≤50years and patients aged >50years, respectively. Sacrum D50% was a significant risk factor in patients aged >50years (P=.04), whereas V55Gy of the sacrum and V55Gy of the pelvic bones were insignificant (P=.33 and P=.18, respectively). A dose-effect curve for sacrum D50% in patients aged >50years showed that reduction of sacrum D50% from 40 GyEQD2 to 35 GyEQD2 reduces PIF risk from 45% to 22%. PIF is common after treatment of LACC and is mainly seen in patients aged >50years. Our data indicate that PIFs are not related to lymph node boosts but rather to dose and volume associated with irradiation of the elective pelvic target. Reducing the prescribed elective dose from 50 to 45Gy may reduce the risk of PIF considerably.

Pelvic insufficiency fracture (PIF) incidence in patients treated with intensity-modulated radiation therapy (IMRT) for gynaecological or anal cancer: single-institution experience and review of the literature

To summarize the results of pelvic insufficiency fracture (PIF) incidence in patients with anal or gynaecological cancer treated by pelvic intensity-modulated radiation therapy (IMRT). The clinical and morphological (CT and/or pelvic MRI) characteristics of patients treated by IMRT at our institution between 2007 and 2014 were analyzed. The global incidence of PIF after external beam radiotherapy and the impact of tumour site (gynaecological or anal cancer) were determined. A dosimetric study was then performed to compare patients with and without pelvic fracture. 341 patients were treated by IMRT for gynaecological or anal cancer between 2007 and 2014. 15 patients experienced at least 1 pelvic fracture after external beam radiotherapy, corresponding to an overall incidence of 4.4%. Age and menopausal status were correlated with an increased fracture risk (p = 0.0274 and p < 0.0001, respectively). The site of the primary tumour (gynaecological or anal canal) was not associated with an excess fracture risk. The median maximum dose received at the fracture site was 50.3 Gy (range: 40.8-68.4 Gy). The incidence of pelvic fracture after IMRT is low, but is higher after the age of 50 and in patients who are postmenopausal. Pre-treatment evaluation of bone density by bone densitometry and phosphorus-calcium assessment could be useful prior to the management of these patients. Advances in knowledge: Pelvic fractures are a frequent complication after radiotherapy. The influence of IMRT and clinical characteristics were evaluated in this study.

Pelvic Insufficiency Fractures.

Pelvic insufficiency fractures may occur in the absence of trauma or as a result of low-energy trauma in osteoporotic bone. With a growing geriatric population, the incidence of pelvic insufficiency fracture has increased over the last 3 decades and will continue to do so. These fractures can cause considerable pain, loss of independence, and economic burden to both the patient and the health care system. While many of these injuries are identified and treated based on plain radiographs, some remain difficult to diagnose. The role of advanced imaging in these cases is discussed. In addition to treating the fracture, medical comorbidities contributing to osteoporosis should be identified and corrected. Specific attention has been given to 25-OH serum vitamin D screening and repletion. Treatment generally consists of providing pain control and assisting patients with mobilization while allowing weight bearing as tolerated. In those unable to do so, invasive techniques such as sacroplasty as well as internal fixation may be beneficial. The role of operative fixation in insufficiency fractures is also discussed.

Pelvic insufficiency fractures in patients with cervical and endometrial cancer treated with postoperative pelvic radiation

There is an increased awareness of pelvic insufficiency fractures (PIF) as a potential morbidity of pelvic radiotherapy (RT). The purpose of this study was to determine the incidence of PIF and assess prognostic factors, including intensity-modulated RT (IMRT), in gynecologic oncology patients treated with postoperative pelvic RT. We performed a retrospective review of all patients with endometrial or cervical carcinoma who received postoperative pelvic RT at our institution during 2000-2008. Patients who received definitive or palliative RT were excluded. A total of 222 patients were identified, of whom 11 (5%) developed PIF at a median time of 11.5months (range, 5.5-87.3months) from RT completion. The 5-year actuarial rate was 5.1% (95% CI 3.3-6.9). In patients with osteoporosis, the 5-year rate was 15.6% compared with 2.9% for those without (P=0.01). Similarly, patients who were on prior hormone-replacement therapy (HRT) had a higher rate (14.8% vs 4.1%, P=0.009). The median body-mass index (BMI) for patients who developed PIF was significantly lower than those who didn't (25.9 vs 27.2, P=0.016). The rate of PIF was 4.9% whether patients received IMRT or conventional RT. The 5-year risk of PIF for postoperative pelvic RT in cervical and endometrial cancer is 5.1%. Women with history of osteoporosis, prior HRT, or low BMI need to be counseled about the risk of PIF. The use of IMRT did not decrease PIF, but further studies are needed to determine if a dose/volume relationship exists between RT and PIF.

Parathyroid Hormone 1-34(Teriparatide) Treatment in Pelvic Insufficiency Fractures - A Report of Two Cases -

As a result of aging population, the incidence of pelvic insufficiency fracture has been increasing. Pain-related immobility caused by pelvic insufficiency fractures may result in a serious dependency and high mortality with preexisting comorbidities. We present two cases of pelvic insufficiency fracture in elderly patients which had good clinical outcome by parathyroid hormone 1-34(teriparatide) treatment as well as a literature review.

Pelvic Insufficiency Fracture After Pelvic Radiotherapy for Cervical Cancer: Analysis of Risk Factors

To investigate the incidence, clinical characteristics, and risk factors of pelvic insufficiency fracture (PIF) after pelvic radiotherapy (RT) in cervical cancer. Medical records and imaging studies, including bone scintigraphy, CT, and MRI of 557 patients with cervical cancer who received whole-pelvic RT between January 1998 and August 2005 were reviewed. Eighty-three patients were diagnosed as having PIF after pelvic RT. The 5-year cumulative incidence of PIF was 19.7%. The most commonly involved site was the sacroiliac joint. Pelvic pain developed in 48 patients (57.8%) at diagnosis. Eleven patients (13.3%) needed admission or narcotics because of severe pain, and others had good relief of symptoms with conservative management. In univariate analysis, age>or=55 years (p<0.001), anteroposterior/posteroanterior parallel opposing technique (p=0.001), curative treatment (p<0.001), and radiation dose>or=50.4 Gy (p=0.005) were the predisposing factors for development of PIF. Concurrent chemotherapy (p=0.78) was not significant. Multivariate analysis showed that age>or=55 years (p<0.001), body weight<55 kg (p=0.02), curative treatment (p=0.03), and radiation dose>or=50.4 Gy (p=0.04) were significant predisposing factors for development of PIF. The development of PIF is not rare after pelvic RT. The use of multibeam arrangements to reduce the volume and dose of irradiated pelvic bone can be helpful to minimize the risk of fracture, especially in elderly women with low body weight.

Pelvic Insufficiency Fractures After Pelvic Radiotherapy for Cervical Cancer: Analysis of Risk Factors

Pelvic Insufficiency Fractures After Pelvic Radiotherapy for Cervical Cancer: Analysis of Risk Factors

Pelvic insufficiency fractures in postmenopausal woman with advanced cervical cancer treated by radiotherapy.

To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight.