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

Fracture Risk Prediction Using the Fracture Risk Assessment Tool in Individuals With Cancer

Importance

The Fracture Risk Assessment Tool (FRAX) is a fracture risk prediction tool for 10-year probability of major osteoporotic fracture (MOF) and hip fracture in the general population. Whether FRAX is useful in individuals with cancer is uncertain.

Objective

To determine the performance of FRAX for predicting incident fractures in individuals with cancer.

Design, Setting, and Participants

This retrospective population-based cohort study included residents of Manitoba, Canada, with and without cancer diagnoses from 1987 to 2014. Diagnoses were identified through the Manitoba Cancer Registry. Incident fractures to March 31, 2021, were identified in population-based health care data. Data analysis occurred between January and March 2023.

Main Outcomes and Measures

FRAX scores were computed for those with bone mineral density (BMD) results that were recorded in the Manitoba BMD Registry.

Results

This study included 9877 individuals with cancer (mean [SD] age, 67.1 [11.2] years; 8693 [88.0%] female) and 45 877 individuals in the noncancer cohort (mean [SD] age, 66.2 [10.2] years; 41 656 [90.8%] female). Compared to individuals without cancer, those with cancer had higher rates of incident MOF (14.5 vs 12.9 per 1000 person-years; P < .001) and hip fracture (4.2 vs 3.5 per 1000 person-years; P = .002). In the cancer cohort, FRAX with BMD results were associated with incident MOF (HR per SD increase, 1.84 [95% CI, 1.74-1.95]) and hip fracture (HR per SD increase, 3.61 [95% CI, 3.13-4.15]). In the cancer cohort, calibration slopes for FRAX with BMD were 1.03 for MOFs and 0.97 for hip fractures.

Conclusions and Relevance

In this retrospective cohort study, FRAX with BMD showed good stratification and calibration for predicting incident fractures in patients with cancer. These results suggest that FRAX with BMD can be a reliable tool for predicting incident fractures in individuals with cancer.

Prevention and management of radiotherapy-related toxicities in gynecological malignancies. Position paper on behalf of AIRO (Italian Association of Radiotherapy and Clinical Oncology)

Multi-modal therapies for gynecological cancers management may determine a wide range of side effects which depend on therapy-related factors and patient characteristics and comorbidities. Curative or adjuvant pelvic radiotherapy is linked with acute and late toxicity due to irradiation of organs at risk, as small and large bowel, rectum, bladder, pelvic bone, vagina and bone marrow. Successful toxicity management varies with its severity, Radiation Centre practice and experience and skills of radiation oncologists. This position paper was designed by the Italian Association of Radiation and Clinical Oncology Gynecology Study Group to provide radiation oncologists with evidence-based strategies to prevent and manage acute and late toxicities and follow-up recommendations for gynecological cancer patients submitted radiotherapy. Six workgroups of radiation oncologists with over 5 years of experience in gynecologic cancers were setup to investigate radiotherapy-related toxicities. For each topic, PubMed database was searched for relevant English language papers from January 2005 to December 2022. Titles and abstracts of results were checked to verify suitability for the document. Reference lists of selected studies and review papers were added if pertinent. Data on incidence, etiopathogenesis, prevention, treatment and follow-up of acute and late side effects for each organ at risk are presented and discussed.

A Comprehensive Narrative Review of the Impact of Pelvic Radiotherapy on Pelvic Bone Health: Pathophysiology, Early Diagnosis, and Prevention Strategies

Radiotherapy is a commonly used modality in pelvic malignancies such as prostate, gastrointestinal, or gynecological, either as a primary treatment or an adjuvant post-surgery. Despite its positive impact on the prognosis of these patients, it was found in several studies that it contributes to insufficiency fractures in different sites of the pelvis, more commonly in the sacral ala. This is particularly true for elderly patients. There are several hypotheses on how radiotherapy affects bone health, as it destroys the bone matrix and causes obliterative vasculitis. Several imaging techniques, particularly magnetic resonance imaging (MRI), help detect the radiotherapy-induced fracture and distinguish it from metastases. Some modalities, such as intensity-modulated radiotherapy (IMRT) and brachytherapy, have decreased fracture risk by escaping the adjacent structures to the targeted organ. Pharmacological interventions such as amifostine and desferrioxamine are promising in terms of bone protection, which necessitates further studies to confirm their mechanism of action.

Pelvic Bone Marrow Sparing Intensity Modulated Radiation Therapy Reduces the Bone Mineral Density Loss of Patients With Cervical Cancer

PURPOSE

To test the efficacy and feasibility of pelvic bone marrow sparing intensity modulated radiation therapy (PBMS-IMRT) in reducing bone density loss for patients with cervical cancer undergoing pelvic radiation therapy (RT).

METHODS AND MATERIALS

Patients with nonsurgical cervical cancer with stage Ib2-IIIc cancer were randomly allocated into the PBMS group or the control group. The PBMS group additionally received pelvic bone marrow dose constraint. Computed tomography (CT) imaging sets were acquired at baseline and at 1, 3, 6, 9, and 12 months after treatment. Radiation dose and Hounsfield unit were registered. Bone density loss rates and fracture events at different follow-up time points were recorded.

RESULTS

Data from 90 patients in the PBMS group and 86 patients in the control group were used for statistical analysis, which included 30 and 26 patients with extended-field radiation therapy (EFR), respectively. The median follow-up for all patients was 12 months. Compared with baseline, the bone density of all bones at the last follow-up decreased by 43% and 53% in the PBMS and control groups, respectively, with the most significant decline at 1 month after treatment. Although patients without EFR received minimal irradiation in the upper lumbar spine, a 22.33% decrease in bone density was detected. In the group of patients with EFR, the decrease was 51.18% (P < .01). Lumbar or pelvic fracture incidence rates of patients in the PBMS and control groups were 7.8% and 12.79%, respectively. Among the dosimetric parameters, mean dose had the strongest correlation with bone density loss.

CONCLUSIONS

In patients undergoing pelvic RT, the loss of bone density can begin to appear early after RT, and it can occur either inside or outside of the irradiation field. Results of this study showed that PBMS-IMRT reduced bone mineral density loss compared with IMRT alone.

A prospective single-arm study on the relationship between dose-volume parameters of pelvic functional bone marrow and acute hematological toxicities during intensity-modulated radiotherapy with or without concurrent chemotherapy for uterine cervical/endometrial cancer

BACKGROUND

FLT-PET/CT can accurately identify and locate functional bone marrow (FBM) with hematopoietic capability, the FBM were divided into two levels as FBM1 (strongest hemopoietic ability region)and FBM2 (moderate hemopoietic ability region) via FLT-PET/CT. The purpose of this study was to explore the relationship between dose-volume parameters of pelvic FBM and hematologic toxicity (HT) during radiotherapy with or without concurrent chemotherapy for uterine cervical/endometrial cancer.

METHODS

From December 2016 to September 2021, ninety-seven uterine cervical/endometrial cancer patients received intensity-modulated radiation therapy were prospectively recruited in this single-arm, prospective, phase II trial. Blood counts were reviewed weekly during radiotherapy. Single- and multifactor regression methods were used to analyze the relationships between dose-volume parameters of FBM1/2 and grade ≥ 2 HT. ROC curves were used to determine the cutoff values for the dose-volume parameters of FBM1/2.

RESULTS

The incidence of grade ≥ 2 leukopenia, neutropenia, thrombocytopenia and anemia in patients during radiotherapy was 63.9%, 45.4%, 19.6% and 38.8% respectively, and the median occurrence time was the 29th, 42th, 35th and 31th day, respectively. Multivariate regression analysis showed that the Dmax of FBM1 was significantly related to grade ≥ 2 leukopenia (OR = 1.277 95% CI 1.067-1.528, P = 0.008), Dmean of FBM2 was significantly related to grade ≥ 2 thrombocytopenia (OR = 1.262 95% CI 1.066-1.494, P = 0.007), and V10 of FBM1 was significantly related to grade ≥ 2 anemia (OR = 1.198 95% CI 1.003-1.431, P = 0.046). The incidence of grade ≥ 2 leukopenia for patients with FBM1 Dmax < 53 Gy was lower than that for patients with FBM1 Dmax ≥ 53 Gy (53.4% vs. 95.8%, P < 0.001). The incidence of grade ≥ 2 thrombocytopenia in patients with FBM2 Dmean < 33 Gy was lower than that in patients with FBM2 Dmean ≥ 33 Gy (0 vs. 28.4%, P < 0.001). The incidence of grade ≥ 2 anemia for patients with FBM1 V10 < 95% was lower than that in patients with FBM1 V10 ≥ 95% (24.4% vs. 57.1%, P = 0.003).

CONCLUSIONS

Grade ≥ 2 HT usually occurs in the 4th week of radiotherapy for patients with uterine cervical/endometrial cancer. The Dmax and V10 of FBM1 and the Dmean of FBM2 were significantly associated with the occurrence of grade ≥ 2 HT. The recommended optimal dose constraints were FBM1 Dmax < 53 Gy, V10 < 95%, and FBM2 Dmean <33 Gy.

Pelvic insufficiency fractures after intensity modulated radiation therapy combined with chemotherapy for cervix carcinoma: Incidence and impact of bone mineral density

Background and Purpose

The aim of this study was to evaluate the incidence and predictive factors of Pelvic Insufficiency Fractures (PIFs) occurring after Intensity Modulated Radiation Therapy (IMRT) combined with chemotherapy for locally advanced cervical cancer (CC).

Material and methods

Medical records of patients receiving radio-chemotherapy with IMRT between 2010 and 2020 for advanced CC were reviewed. PIFs were detected during follow-up on pelvic Magnetic Resonance Imaging (MRI) or Computed Tomography (CT). The cumulative incidence rate of PIFs and its confidence interval were calculated at 2 and 5 years of follow-up. Pre-therapeutic Bone Mineral Density (BMD) (g/cm³) was evaluated on CT simulation for sacrum and the fourth lumbar (L4) vertebrae. Sacrum dosimetric parameters (V30Gy, V40Gy, D50%, Dmean) were analyzed.

Results

136 patients were included. The median follow-up was 4.4 years. Median dose of D50% and V40Gy sacrum were 35.2 Gy (20.6-46.4) and 32.2% (7.2-73.4) respectively. The 2-year and 5-year cumulative incidence rates were 15.7% (95% CI: 9.88-22.71) and 22% (95% CI: 14.58-30.45) respectively. Median time interval between RT completion and PIFs' detection was 11.5 months (IQR: 7.4-22.3). Univariate analysis showed that older age (p < 0.01), postmenopausal status at baseline (p < 0.01), and lower sacral and spinal BMD at baseline (respectively p < 0.001 and p < 0.01) were significantly associated to all sites of PIFs, and lower sacral BMD with sacral fractures (p < 0.001).

Conclusion

Post-IMRT PIFs were detected in 18.4% of patients with locally advanced CC. Individual predisposing factors as older age, postmenopausal status, decreased bone density on the CT simulation were mainly predictive.

Fracture risk and assessment in adults with cancer

Individuals with cancer face unique risk factors for osteoporosis and fractures. Clinicians must consider the additive effects of cancer-specific factors, including treatment-induced bone loss, and premorbid fracture risk, utilizing FRAX score and bone mineral densitometry when available. Pharmacologic therapy should be offered as per cancer-specific guidelines, when available, or local general osteoporosis guidelines informed by clinical judgment and patient preferences. Our objective was to review and summarize the epidemiologic burden of osteoporotic fracture risk and fracture risk assessment in adults with cancer, and recommended treatment thresholds for cancer treatment-induced bone loss, with specific focus on breast, prostate, thyroid, gynecological, multiple myeloma, and hematopoietic stem cell transplant. This narrative review was informed by PubMed searches to July 25, 2022, that combined terms for cancer, stem cell transplantation, fracture, bone mineral density (BMD), trabecular bone score, FRAX, Garvan nomogram or fracture risk calculator, QFracture, prediction, and risk factors. The literature informs that cancer can impact bone health in numerous ways, leading to both systemic and localized decreases in BMD. Many cancer treatments can have detrimental effects on bone health. In particular, hormone deprivation therapies for hormone-responsive cancers such as breast cancer and prostate cancer, and hematopoietic stem cell transplant for hematologic malignancies, adversely affect bone turnover, resulting in osteoporosis and fractures. Surgical treatments such as hysterectomy with bilateral salpingo-oophorectomy for gynecological cancers can also lead to deleterious effects on bone health. Radiation therapy is well documented to cause localized bone loss and fractures. Few studies have validated the use of fracture risk prediction tools in the cancer population. Guidelines on cancer-specific treatment thresholds are limited, and major knowledge gaps still exist in fracture risk and fracture risk assessment in patients with cancer. Despite the limitations of current knowledge on fracture risk assessment and treatment thresholds in patients with cancer, clinicians must consider the additive effects of bone damaging factors to which these patients are exposed and their premorbid fracture risk profile. Pharmacologic treatment should be offered as per cancer-specific guidelines when available, or per local general osteoporosis guidelines, in accordance with clinical judgment and patient preferences.

Diagnostic Significance of 18F-FDG PET/CT Imaging Coupled with Magnetic Resonance Imaging of the Entire Body for Bone Metastases

Objective

To see if 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) imaging paired with MR diffusion imaging can help doctors diagnose bone metastases.

Methods

From September 2020 to December 2021, a total of 30 individuals with probable bone metastases were recruited for the trial. With an average interval of four days, MAGNETIC resonance whole-body diffusion imaging (MR whole-body diffusion imaging) was performed on each of the 30 patients who had 18F-FDG PET/CT. The SUVmax values of the group with bone metastases were compared to those of the group without bone metastases. In this study, 18F-FDG PET/CT imaging, MR whole-body diffusion imaging, and their combination were examined. The researchers compared the results when 18F-FDG PET/CT imaging, whole-body MRI diffusion scans, and their combination indicated abnormal bone lesions. By comparing the diagnostic efficacy of 18F-FDG PET/CT imaging, MR whole-body diffusion imaging, and their combination, as well as accuracy, sensitivity, and specificity, the three techniques for diagnosing bone metastases will be evaluated for diagnostic usefulness. Results: the SUV max values of patients with bone metastases were significantly different from those of patients without bone metastases, as determined by 18F-FDG PET/CT imaging (P < 0.05). Using 18F-FDG PET/CT imaging, MR whole-body diffusion imaging, and their combined detection of aberrant bone lesions in various areas, we found statistically significant differences.

Conclusion

The use of 18F-FDG PET/CT imaging in conjunction with MR whole-body diffusion imaging in the diagnosis of bone metastases can be very helpful.

Clinical and MRI features of sacral insufficiency fractures after radiotherapy in patients with cervical cancer

Background

To determine the incidence, clinical and MRI features of sacral insufficiency fracture (SIF) after radiotherapy (RT) in patients with cervical cancer.

Methods

Our study included 167 patients with cervical cancer after radiotherapy that underwent pelvic MRI for follow-up. MRIs included pre-enhanced T1-weighted, coronal fat-Suppressed T2-weighted (FS-T2W) and enhanced T1-weighted imaging. The clinical and MRI dates were reviewed. The gold standard of SIF was based on radiologic findings, clinical data and follow-up at least 12 months.

Results

28 patients (10.8%) with 47 sites were diagnosed with SIFs, including 9 patients with unilateral SIF and 19 patients with bilateral SIFs. The median age was 60 years (range 41–72 years), and 89.3% (25/28) of patients were postmenopausal. 64.3% (18/28) of patients were symptomatic, and 53.6% of patients (15/28) had concomitant pelvic fractures. The median interval time from RT to SIFs was 10 months (range 3–34 months). For the lesion-wise analysis based on all MR images, all lesions were detected by visualizing bone marrow edema patterns, and fracture lines were detected in 64.6% (31/47) of SIFs. No soft-tissue tumors were founded. For each MRI sequence analysis, coronal FS-T2WI detected the most bone marrow edema pattern and fracture line than T1WI or enhanced T1WI.

Conclusion

SIF is a common complication in cervical cancer after radiotherapy, which has some certain clinical and MRI features. Coronal FS-T2WI may be more useful to detect and characterize these fractures than other imaging sequences.

Circulating tumor-tissue modified HPV DNA analysis for molecular disease monitoring after chemoradiation for anal squamous cell carcinoma: a case report

Squamous cell carcinoma (SCC) of the anus typically arises after human papillomavirus (HPV) infection. We report on the use of molecular disease monitoring using a novel blood test measuring circulating tumor-tissue -modified HPV DNA in two patients with anal cancer. Two patients with anal SCC received concurrent chemotherapy and radiation therapy (chemoRT) with curative intent, one with a T2N0 anal margin squamous cell carcinoma with a history of AIDS, and one with a T3N0 anal squamous cell carcinoma and a history of concurrent prostate cancer. HPV genotyping at diagnosis confirmed the presence of HPV16 DNA in both cases. Circulating, tumor-tissue-modified HPV DNA (TTMV-HPV DNA) was measured in the peripheral blood utilizing digital PCR at baseline and in follow-up. Disease burden was assessed post-treatment with standard anoscopy, biopsy, and PET/CT. Plasma TTMV-HPV DNA levels were elevated at diagnosis, and decreased during and after chemoRT completion in both cases. During post treatment surveillance, TTMV-HPV DNA levels correlated with disease status including one case with progressive local recurrence within 2 months, and one case with 12 months of local control both confirmed by biopsy. These case studies present the first use of circulating tumor-tissue-modified HPV DNA as a biomarker for anal cancer. Further study of this blood test an adjunct to standard treatment and monitoring is warranted in HPV-positive anal cancer.

Relations Between Bone Quantity, Microarchitecture, and Collagen Cross-links on Mechanics Following In Vivo Irradiation in Mice

Humans are exposed to ionizing radiation via spaceflight or cancer radiotherapy, and exposure from radiotherapy is known to increase risk of skeletal fractures. Although irradiation can reduce trabecular bone mass, alter trabecular microarchitecture, and increase collagen cross‐linking, the relative contributions of these effects to any loss of mechanical integrity remain unclear. To provide insight, while addressing both the monotonic strength and cyclic‐loading fatigue life, we conducted total‐body, acute, gamma‐irradiation experiments on skeletally mature (17‐week‐old) C57BL/6J male mice (n = 84). Mice were administered doses of either 0 Gy (sham), 1 Gy (motivated by cumulative exposures from a Mars mission), or 5 Gy (motivated by clinical therapy regimens) with retrieval of the lumbar vertebrae at either a short‐term (11‐day) or long‐term (12‐week) time point after exposure. Micro‐computed tomography was used to assess trabecular and cortical quantity and architecture, biochemical composition assays were used to assess collagen quality, and mechanical testing was performed to evaluate vertebral compressive strength and fatigue life. At 11 days post‐exposure, 5 Gy irradiation significantly reduced trabecular mass (p < 0.001), altered microarchitecture (eg, connectivity density p < 0.001), and increased collagen cross‐links (p < 0.001). Despite these changes, vertebral strength (p = 0.745) and fatigue life (p = 0.332) remained unaltered. At 12 weeks after 5 Gy exposure, the trends in trabecular bone persisted; in addition, regardless of irradiation, cortical thickness (p < 0.01) and fatigue life (p < 0.01) decreased. These results demonstrate that the highly significant effects of 5 Gy total‐body irradiation on the trabecular bone morphology and collagen cross‐links did not translate into detectable effects on vertebral mechanics. The only mechanical deficits observed were associated with aging. Together, these vertebral results suggest that for spaceflight, irradiation alone will likely not alter failure properties, and for radiotherapy, more investigations that include post‐exposure time as a positive control and testing of both failure modalities are needed to determine the cause of increased fracture risk. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

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.

Chemoradiation for Anal Cancer: Clinical Outcomes and Strategies to Optimize the Therapeutic Ratio According to HPV Status

The incidence of anal cancer in the United States has increased in recent years, primarily related to the increasing incidence of HPV-associated anal squamous cell carcinoma, which is estimated to represent 80%-95% of anal cancers. Similar to head and neck cancer, HPV association has been demonstrated to be a strong positive prognostic factor in patients with anal cancer. Encouraging results from a number of studies investigating treatment de-escalation for HPV-associated oropharyngeal cancer support the notion that similar attempts may be feasible in HPV-associated anal cancer; however, the data to support this hypothesis are currently lacking. Studies are needed to determine how, if at all, HPV status should impact the management of patients with anal cancer. This review summarizes the relationship between HPV association and outcomes for patients with anal cancer, and how HPV status may impact the treatment of patients with anal cancer going forward.

Toxicity and Efficacy of Concurrent Androgen Deprivation Therapy, Pelvic Radiotherapy, and Radium-223 in Patients with De Novo Metastatic Hormone-Sensitive Prostate Cancer

PURPOSE

Radium-223 is an alpha-emitting radionuclide associated with overall survival (OS) improvement in metastatic castration-resistant prostate cancer (mCRPC). External beam radiotherapy (EBRT) to prostate extends OS in men with metastatic hormone-sensitive prostate cancer (mHSPC) limited to less than 4 metastases. We hypothesized that combination radium-223 + pelvic EBRT could safely deliver maximal radiotherapy doses to primary and metastatic prostate cancer and may improve disease control.

PATIENTS AND METHODS

Thirty patients with de novo bone metastatic mHSPC who had commenced androgen deprivation therapy (ADT) and docetaxel were recruited to this single-arm, open-label, prospective clinical trial: Neo-adjuvant Androgen Deprivation Therapy, Pelvic Radiotherapy and RADium-223 (ADRRAD; for new presentation T1-4 N0-1 M1B adenocarcinoma of prostate). Study treatments were: ADT, 6 cycles of radium-223 q28 days, conventionally fractionated prostate radiotherapy (74 Gy) and simultaneous integrated boost to pelvic lymph nodes (60 Gy).

RESULTS

No grade 4/5 toxicity was observed. Three patients experienced grade 3 leukopenia, and 1 each experienced grade 3 neutropenia and thrombocytopenia; all were asymptomatic. One patient each experienced grade 3 dysuria and grade 3 urinary infection. No grade 3 gastrointestinal (GI) toxicity was observed. On treatment completion, there was a signal of efficacy; 24 (80%) patients had whole-body MRI evidence of tumor response or stability. Twenty-seven (90%) patients showed a reduction in alkaline phosphatase (ALP) compared with pretreatment levels. Median progression-free survival was 20.5 months.

CONCLUSIONS

This is the first trial of combination ADT, radium-223, and EBRT to pelvis, post docetaxel. The combination was safe, with an efficacy signal. Multicenter randomized controlled trials (RCT) are warranted.

Utility of adjuvant whole abdominal radiation therapy in ovarian clear cell cancer (OCCC): a pragmatic cohort study of women with classic immuno-phenotypic signature

BACKGROUND

To evaluate the initial experience and clinical utility of first-line adjuvant intensity-modulated whole abdominal radiation therapy (WART) in women with ovarian clear cell cancer (OCCC) referred to an academic center.

METHODS

Progression-free and overall survival was analyzed in a pragmatic observational cohort study of histologically pure OCCC patients over-expressing HNF-1ß treated between 2013 and end-December 2018. An in-house intensity-modulated WART program was developed from a published pre-clinical model. Radiation dose-volume data was curated to American Association of Physics in Medicine (AAPM) Task Group 263 recommendations. A dedicated database prospectively recorded presenting characteristics and outcomes in a standardized fashion.

RESULTS

Five women with FIGO (2018) stage IA to IIIA2 OCCC were treated with first-line WART. Median age was 58 years (range 47-68 years). At diagnosis CA-125 was elevated in 4 cases (median 56 kU/L: range 18.4-370 kU/L) before primary de-bulking surgery. Severe premorbid endometriosis was documented in 3 patients. At a median follow-up of 77 months (range 16-83 mo.), all patients remain alive and progression-free on clinical, biochemical (CA-125), and ¹⁸Fluoro-deoxyglucose (FDG) PET/CT re-evaluation. Late radiation toxicity was significant (G3) in 1 case who required a limited bowel resection and chronic nutritional support at 9 months post-WART; 2 further patients had asymptomatic (G2) osteoporotic fragility fractures of axial skeleton at 12 months post-radiation treated with anti-resorptive agents (denosumab).

CONCLUSIONS

The clinical utility of intensity-modulated WART in OCCC over-expressing HNF-1β was suggested in this small observational cohort study. The hypothesis that HNF-1β is a portent of platinum-resistance and an important predictive biomarker in OCCC needs further confirmation. Curating multi-institutional cohort studies utilizing WART by means of "Big Data" may improve OCCC care standards in the future.

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

Purpose

The 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.

Methods

62 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.

Results

Out 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.

Conclusion

The 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.

Ten Commandments for the Diagnosis of Bone Tumors

The diagnosis of tumors and tumorlike lesions of bone is a routine part of both general and specialist radiologic practices. The spectrum of disorders ranges from the small incidental lesion to the potentially life-limiting malignancies whether primary or secondary. In this review, authored by experts from several European orthopaedic oncology centers, we present a collection of pieces of advice in the form of 10 commandments. Adherence in daily practice to this guidance should help minimize adverse patient experiences and outcomes.

Tailoring the radiotherapy approach in patients with anal squamous cell carcinoma based on inguinal sentinel lymph node biopsy

BACKGROUND AND OBJECTIVES

The aim of our study was to analyze the results of selective inguinal node irradiation in patients with anal cancer, based on the biopsy of the inguinal sentinel lymph node (SLN), in terms of local control and prognosis.

METHODS

Records of patients with anal squamous cell carcinoma from January 2001 to December 2016 were retrospectively reviewed. Tc99 lymphoscintigraphy was performed in all the clinically inguinal negative patients, followed by radio-guided surgical removal of the inguinal SLN. All patients were treated with combined radiochemotherapy. In patients with negative sentinel nodes, the inguinal area was excluded in the radiotherapy field.

RESULTS

A total of 123 patients, 76 females (61.8%), mean age 60.1 ± 12.19 years old, underwent intraoperative lymph node retrieval. The histological analysis showed metastasis in the SLN in 28 patients (22.8%). The mean follow-up was 43.44 ± 31.86 months. No inguinal recurrence was observed in patients with negative inguinal sentinel node(s). A statistically significant difference was observed for overall and disease-free survivals in a patient with positive and negative inguinal sentinel nodes.

CONCLUSIONS

In patients with anal canal cancer, the exclusion of the inguinal regions from the radiotherapy field, in patients with negative SLN, does not compromise locoregional control nor prognosis.

Pelvic insufficiency fracture or bone metastasis after radiotherapy for cervical cancer? The added value of DWI for characterization

OBJECTIVES

We sought to determine the added value of diffusion-weighted magnetic resonance imaging (DWI) in the differentiation of pelvic insufficiency fracture (PIF) from bone metastasis after radiotherapy in cervical cancer patients.

METHODS

In the present study, 42 cervical cancer patients after radiotherapy with 61 bone lesions (n = 40, PIFs; n = 21, bone metastasis) were included. Conventional MRI and DWI were performed in all patients. For qualitative imaging diagnosis, two sets of images were reviewed independently by three observers, including a conventional MRI set (unenhanced T1-weighted, T2-weighted, and enhanced T1-weighted images) and a DWI set (conventional MRIs, DW images, and ADC maps). The mean ADC value of each lesson was measured on ADC maps. The diagnostic performance was assessed by using the area under the receiver operating characteristic curve (Az), and sensitivity and specificity were determined.

RESULTS

For all observers, the Az value and sensitivity of the DWI set showed improvement compared with the conventional MRI set. The observer who had the least experience (3 years) demonstrated significant improvement in diagnostic performance with the addition of DWI; Az value increased from 0.804 to 0.915 (p = 0.042) and sensitivity increased from 75.0 to 92.5% (p = 0.035). The mean ADCs of the PIFs were significantly higher than the bone metastases (p < 0.001); ADC values > 0.97 × 10-3 mm2/s yielded an Az of 0.887, a sensitivity of 92.5%, and a specificity of 76.2%.

CONCLUSIONS

The addition of DWI to conventional MRI improved the differentiation of PIF from bone metastasis after RT in patients with cervical cancer.

KEY POINTS

• DWI showed additive value to conventional MRI in the differentiation of PIF from bone metastasis after RT. • For qualitative diagnosis, the addition of DWI can improve diagnostic performance compared with conventional MRI alone and can particularly improve the sensitivity. • Quantitative ADC assessment showed potential value for identifying PIF from bone metastasis.

Prehabilitation for patient positioning: pelvic exercises assist in minimizing inter-fraction sacral slope variability during radiation therapy

Reproducible patient positioning is essential for precision in radiation therapy (RT) delivery. We tested the hypothesis that a structured daily pre-treatment stretching regimen is both feasible and effective for minimizing variability in positioning, as measured by sacral slope angles (SSA). Eight female subjects undergoing pelvic radiotherapy performed a structured daily hip exercise regimen (extension and external rotation) immediately prior to both simulation imaging and daily treatment, throughout their RT course. This exercising cohort was compared to a retrospective review of 20 subjects (17 women and 3 men) undergoing RT, who had usual care. SSA measurements from daily pre-treatment imaging were compared to SSA measurements from the simulation CT. The average variation in SSA among the intervention subjects was 0.91° (± 0.58°), with a range among subjects of 0.57°-1.27°. The average variation for the control subjects was 2.27° (± 1.43°), ranging 1.22°-5.09°. The difference between the two groups was statistically significant (p = 0.0001). There was a statistically significant SSA variation between groups at each week of treatment. There was no significant variation among the intervention subjects between week 1 and later weeks, whereas subjects in the control group demonstrated significant SSA variation between week 1 and later weeks. We demonstrated a significant decrease in the variability of SSA by implementing a simple pre-treatment exercise program, while control subjects exhibited increasing variation in SSA over the course of treatment. We conclude that there is a potential benefit of prehabilitation during pelvic RT; however, a larger randomized control trial is required to confirm the findings.Clinical Trial: This research project was approved by the University of Massachusetts Medical School IRB (IRB ID H00012353) on January 21, 2017. The study is listed on ClinicalTrials.gov, provided by the U.S. National Library of Medicine, found with identifier NCT03242538.

Sacral Fractures and Sacroplasty

Sacral fractures result from high-impact trauma or in the form of insufficiency or pathologic fractures, resulting from osteoporosis, radiation therapy, or malignancy. In the emergency setting, the escalating use of computed tomography has substantially increased diagnosis of sacral fractures, which are frequently occult on radiographs. Radiologists should be familiar with and create reports using the most current fracture classification systems, because this improves communication with the treatment team and optimizes patient care. Sacroplasty is a safe, minimally invasive treatment option for many types of sacral fractures. It provides rapid and durable pain relief, with a low incidence of complications.

Effects of ex vivo ionizing radiation on collagen structure and whole-bone mechanical properties of mouse vertebrae

Bone can become brittle when exposed to ionizing radiation across a wide range of clinically relevant doses that span from radiotherapy (accumulative 50 Gy) to sterilization (~35,000 Gy). While irradiation-induced embrittlement has been attributed to changes in the collagen molecular structure, the relative role of collagen fragmentation versus non-enzymatic collagen crosslinking remains unclear. To better understand the effects of radiation on the bone material without cellular activity, we conducted an ex vivo x-ray radiation experiment on excised mouse lumbar vertebrae. Spinal tissue from twenty-week old, female, C57BL/6J mice were randomly assigned to a single x-ray radiation dose of either 0 (control), 50, 1000, 17,000, or 35,000 Gy. Measurements were made for collagen fragmentation, non-enzymatic collagen crosslinking, and both monotonic and cyclic-loading compressive mechanical properties. We found that the group differences for mechanical properties were more consistent with those for collagen fragmentation than for non-enzymatic collagen crosslinking. Monotonic strength at 17,000 and 35,000 Gy was lower than that of the control by 50% and 73% respectively, (p < 0.001) but at 50 and 1000 Gy was not different than the control. Consistent with those trends, collagen fragmentation only occurred at 17,000 and 35,000 Gy. By contrast, non-enzymatic collagen crosslinking was greater than control for all radiation doses (p < 0.001). All results were consistent both for monotonic and cyclic loading conditions. We conclude that the reductions in bone compressive monotonic strength and fatigue life due to ex vivo ionizing radiation are more likely caused by fragmentation of the collagen backbone than any increases in non-enzymatic collagen crosslinks.

Influence of radiation exposure pattern on the bone injury and osteoclastogenesis in a rat model

Radiotherapy, one of the clinical treatments of cancer, is accompanied by a high risk of damage to healthy tissues, such as bone loss and increased risk of fractures. The aim of the present study was to establish a rat model of local and systemic bone injury by focal irradiation, in order to study the etiological mechanism and intervention. The proximal metaphyseal region of the left hindlimb of male Sprague-Dawley rats were exposed to a single 2 Gy or three 8 Gy doses delivered on days 1, 3 and 5 using a small animal irradiator, the changes in bone volume and microarchitecture were evaluated, and the mineral apposition rate (MAR) was assessed. Furthermore, bone marrow-derived macrophages (BMMs) were isolated and induced to osteoclasts. It has been demonstrated that a single dose of 2 Gy may result in a significant loss of lumbar bone density at 3 days post-irradiation, however this is restored at 30 days post-irradiation. In the 3x8 Gy irradiation rat model, there was a rapid decrease in the aBMD of lumbar spine at 3 days and at 7 days post-irradiation, and the aBMD decline persisted even at 60 days post-irradiation. In addition, microCT analysis revealed a persistent decline in bone volume and damage in microarchitecture in the 3x8 Gy irradiation model, accompanied by a decrease in MAR, index of the decline in bone-forming ability. In the cellular mechanism, a single 2 Gy local irradiation mainly manifested as an enhancement of the BMMs osteoclastogenesis potential, which was different from the osteoclastogenesis inhibition after high-dose focal irradiation (3x8 Gy). In summary, the irradiation with simulated clinical focal fractionated radiotherapy exerts short- and long-term systemic injury on bone tissue, characterized by different osteoclastogenesis potential between the high dose mode and a single 2 Gy focal irradiation. Physicians must consider the irreversibility of bone damage in clinical radiotherapy.

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

PURPOSE

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.

METHODS AND MATERIALS

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.

RESULTS

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.

CONCLUSIONS

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.

A multi-disciplinary model of survivorship care following definitive chemoradiation for anal cancer

Following definitive chemoradiation for anal squamous cell carcinoma (ASCC), patients face a variety of chronic issues including: bowel dysfunction, accelerated bone loss, sexual dysfunction, and psychosocial distress. The increasing incidence of this disease, high cure rates, and significant long-term sequelae warrant increased focus on optimal survivorship care following definitive chemoradiation. In order to establish our survivorship care model for ASCC patients, a multi-disciplinary team of experts performed a comprehensive literature review and summarized best practices for the multi-disciplinary management of this unique patient population. We reviewed principle domains of our survivorship approach: (1) management of chronic toxicities; (2) sexual health; (3) HIV management in affected patients; (4) psychosocial wellbeing; and (5) surveillance for disease recurrence and survivorship care delivery. We provide recommendations for the optimization of survivorship care for ASCC patients can through a multi-disciplinary approach that supports physical and psychological wellness.

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

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High rates of PIF are detected 3 years after VMAT based CRT for rectal cancer.

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Patients with PIFs received non-significantly higher V30 Gy to sacroiliac joints.

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3 arc VMAT techniques can be optimized for bone.

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Proton beam therapy has the potential for further optimization for bone.

Pelvic insufficiency fractures (PIF) is a known but under-acknowledged late effect of pelvic radiotherapy. In rectal cancer, studies describing incidence of PIF and relation to dose volume relationships are lacking. The aim of this study was (i) to analyse dose volume histograms (DVH) from pelvic bones in patients with and without PIF, and (ii) to determine bone sparing capacity of 2 and 3 arc volumetric arc therapy (VMAT), intensity modulated radiotherapy (IMRT) and proton beam therapy (PBT), in rectal cancer patients treated with chemoradiotherapy (CRT).

Material and methods

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.

Results

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.

Conclusions

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.

Increased risk of pelvic fracture after radiotherapy in rectal cancer survivors: A propensity matched study

To determine whether radiotherapy (RT) can increase pelvic fracture risk in rectal cancer survivors. Rectal cancer patients who underwent curative surgery between 1996 and 2011 in Taiwan were retrospectively studied using the National Health Insurance Research Database (NHIRD) of Taiwan. ICD‐9 Codes 808, 805.4‐805.7, 806.4‐806.7, and 820 (including pelvic, sacrum, lumbar, and femoral neck fracture) were defined as pelvic fracture. Propensity scores for RT, age, and sex were used to perform one‐to‐one matches between the RT and non‐RT group. Risks of pelvic and arm fractures were compared by multivariable Cox regression. Of the 32 689 patients, 7807 (23.9%) received RT, and 1616 suffered from a pelvic fracture (incidence rate: 1.17/100 person‐years). The median time to pelvic fracture was 2.47 years. After matching, 6952 patients each in the RT and non‐RT groups were analyzed. RT was associated with an increased risk of pelvic fractures in the multivariable Cox model (hazard ratio (HR): 1.246, 95% confidence interval (CI): 1.037‐1.495, P = 0.019) but not with arm fractures (HR: 1.013, 95% CI: 0.814‐1.259, P = 0.911). Subgroup analyses revealed that RT was associated with a higher pelvic fracture rate in women (HR: 1.431, 95% CI: 1.117‐1.834) but not in men, and the interaction between sex and RT was significant (P = 0.03). The HR of pelvic fracture increased 2‐4 years after RT (HR: 1.707, 95% CI: 1.150‐2.534, P = 0.008). An increased risk of pelvic fracture is noted in rectal cancer survivors, especially women, who receive RT.