Analysis of orthopedic surgery of bone metastases in breast cancer patients

Solitary versus multiple bone metastases in the appendicular skeleton

Aims

We first sought to compare survival for patients treated surgically for solitary and multiple metastases in the appendicular skeleton, and second, to explore the role of complete and incomplete resection (R0 and R1/R2) in patients with a solitary bony metastasis in the appendicular skeleton.

Methods

We conducted a retrospective study on a population-based cohort of all adult patients treated surgically for bony metastases of the appendicular skeleton between January 2014 and December 2019. We excluded patients in whom the status of bone metastases and resection margin was unknown. Patients were followed until the end of the study or to their death. We had no loss to follow-up. We used Kaplan-Meier analysis (with log-rank test) to evaluate patient survival. We identified 506 operations in 459 patients. A total of 120 operations (in 116 patients) were for solitary metastases and 386 (in 345 patients) for multiple metastases. Of the 120 operations, 70 (in 69 patients) had no/an unknown status of visceral metastases (solitary group) and 50 (in 49 patients) had visceral metastases. In the solitary group, 45 operations (in 44 patients) were R0 (resections for cure or complete remission) and 25 (in 25 patients) were R1/R2 (resections leaving microscopic or macroscopic tumour, respectively). The most common types of cancer in the solitary group were kidney (n = 27), lung (n = 25), and breast (n = 20).

Results

The one-year patient survival was 47% (95% confidence interval (CI) 38 to 57) for the solitary bony metastases and 34% (95% CI 29 to 39) for multiple bone metastases (p < 0.001). The one-year patient survival was 64% (95% CI 52 to 75) for solitary bony metastases without/with unknown visceral metastases and 23% (95% CI 11 to 36) for solitary bony metastases with visceral metastases (p < 0.001). The one-year patient survival was 75% (95% CI 62 to 89) for a solitary bony metastasis after R0 surgery and 42% (95% CI 22 to 61) for a solitary bony metastasis with R1/R2 surgery (p < 0.001).

Conclusion

Our study suggests that the surgical treatment of patients with a solitary bony metastasis to the appendicular skeleton results in better survival than for patients with multiple bony metastases. Furthermore, aggressive treatment of a solitary bony metastasis with R0 surgery may improve patient survival.

Exosomes from LSD1 knockdown breast cancer cells activate osteoclastogenesis and inhibit osteoblastogenesis

Bone metastasis is a common and incurable complication of breast cancer. Lysine-specific demethylase 1 (LSD1), a histone demethylase, plays an important role in the metastasis of breast cancer. However, the role of LSD1 in bone metastasis of breast cancer is unclear. We hypothesized that exosomes from LSD1 knockdown breast cancer cells promote bone metastasis by remodeling bone microenvironment. To verify this hypothesis, exosomes from LSD1 knockdown Estrogen receptor-positive cancer cell lines, MCF7 and T47D, were isolated, and the effects of these exosomes on osteoblast and osteoclast differentiation were investigated. Interestingly, exosomes from LSD1 knockdown breast cancer cells inhibited osteoblast differentiation and promoted osteoclast differentiation. Mechanistically, miR-6881-3p was decreased in the exosomes from LSD1 knockdown cells, and miR-6881-3p suppressed the expression of pre-B-cell leukemia homeobox 1 (PBX1) and additional sex combs like-2 (ASXL2), two genes with essential functions in osteoblast and osteoclast differentiations respectively. Transfection of miR-6881-3p into LSD1 knockdown cells reversed the effects of the exosomes on osteoblast and osteoclast differentiations. Our study reveals important roles of LSD1 on the regulation of exosomal miRNAs and the formation of favorable bone microenvironment for metastasis.

Oligometastatic breast cancer and metastasis-directed treatment: an aggressive multimodal approach to reach the cure

Metastatic breast cancer (BC) is considered an incurable disease and is usually treated with palliative intent. However, about 50% of metastatic BCs present with only a few metastatic lesions and are characterized by longer overall survival. These patients, defined as oligometastatic, could benefit from a multimodal approach, which combines systemic therapy with metastasis-directed treatment (stereotactic ablative therapy or surgery). The current definition of oligometastatic seems incomplete since it is based only on imaging findings and does not include biological features, and the majority of relevant data supporting this strategy comes from retrospective or non-randomized studies. However, the chance of reaching long-term complete remission or even a cure has led to the development of randomized trials investigating the impact of combined treatment in oligometastatic BC (OMBC). The SABR-COMET trial, the first randomized study to include BC patients, showed promising results from a combination of stereotactic ablative radiotherapy and systemic therapy. Considering the randomized trial's results, multidisciplinary teams should be set up to select OMBC patients who could achieve long-term survival with aggressive multimodal treatment.

Risk Factors, Patterns, and Distribution of Bone Metastases and Skeletal-Related Events in High-Risk Breast Cancer Patients

BACKGROUND

More than a quarter of breast cancer patients are at risk to develop recurrent metastases to the bone.

OBJECTIVE

This study was designed to identify risk factors and predilections of bone metastasis and skeletal-related events (SRE) in a population of breast cancer survivors initially diagnosed in advanced stages and with high-risks of relapse.

METHODS

Associated risk factors, distribution, and attainable treatment of bone metastasis and SRE were analyzed in a cohort of 1,329 breast cancer patients. The association with dependent variables was subsequently analyzed using multivariable logistic regression. Sociodemographic and adverse clinical characteristics were included as covariates of progression into bone metastasis and SREs.

RESULTS

Of 1329 breast cancer patients, 246 patients (18.5%) were diagnosed as metastatic breast cancer in which 232 of them (94.3%) had bone metastases. Spines were the most common sites of bone metastases (25.6%). In multivariable analysis, advanced stage at diagnosis (OR=1.840, 95%CI:1.198-2.826, P=0.005), luminal subtype (OR=1.788, 95%CI:1.206-2.652, P=0.045), lobular histology (OR=1.795, 95%CI:1.012-3/184, P=0.046), positive axillary lymph node (OR=1.771, 95%CI:1.087-2.886, P=0.022), multiple metabolic comorbidities (OR=2.193, 95%CI:1.371-3.508, P=0.001), early menopause (OR=2.136, 95%CI:1.116-4.464, P=0.046) were significantly associated with risk of recurrent bone metastases. SREs occurred in 89 (68.5%) patients. Several risk factors for SREs were early menopausal age (OR=2.342, P=0.024), advanced stages (OR=1.404, P=0.039), lobular histology (OR=2.279, P=0.007), and having multiple metabolic comorbidities (OR=1.728, P=0.039).

CONCLUSION

Bone metastases and SREs are relatively high in breast cancer patients diagnosed in advanced stages. Luminal subtypes, having multiple metabolic comorbidities, and lobular histology are associated with higher risks of recurrent bone metastases. Living in rural areas and advanced stage at diagnosis as a risk factors for bone metastases might represent a social gradient of care delivery.

Punicalin Attenuates Breast Cancer-Associated Osteolysis by Inhibiting the NF-κB Signaling Pathway of Osteoclasts

Background: Breast cancer bone metastasis and osteoporosis are both severe diseases that seriously threaten human health. These diseases are closely associated with osteolytic lesions. And osteoclasts are the key targets of this pathological process. Given the lack of effective preventive or treatment options against these diseases, the exploitation of new pharmacological agents is critically required.

Method: We assessed the efficacy of punicalin on receptor activator of nuclear factor-κB ligand (RANKL)-mediated osteoclast formation, F-actin ring formation, gene expression, bone resorption, nuclear factor-κB (NF-κB) as well as on mitogen-activated protein kinase (MAPK) signaling pathways and molecular docking in vitro. The impact of punicalin on breast cancer-induced osteoclastogenesis, breast cancer cell proliferation, and apoptosis were examined. Transwell assays were also performed. Moreover, we evaluated in vivo effects of punicalin in postmenopausal osteoporosis models and breast cancer bone metastasis model by micro-CT scanning and histomorphometry.

Results: Punicalin inhibited osteoclast formation, F-actin ring formation, bone resorption, as well as osteoclast-related gene expression by suppressing the NF-κB signaling pathway. In vitro, punicalin also suppressed the breast cancer-induced osteoclastogenesis, and proliferation, migration as well as invasion of MDA-MB-231 cells and dose-dependently promoted their apoptosis. In vivo, punicalin significantly suppressed breast cancer-induced osteolysis, breast cancer-associated bone metastasis, and ovariectomized (OVX)-mediated osteoporosis by repressing osteoclast and breast cancer cell.

Conclusion: Punicalin is expected to offer a novel treatment for the prevention of osteolysis diseases, including osteoporosis and breast cancer-associated osteolysis.

Novel Silver-Functionalized Poly(ε-Caprolactone)/Biphasic Calcium Phosphate Scaffolds Designed to Counteract Post-Surgical Infections in Orthopedic Applications

In this study, we designed and developed novel poly(ε-caprolactone) (PCL)-based biomaterials, for use as bone scaffolds, through modification with both biphasic calcium phosphate (BCP), to impart bioactive/bioresorbable properties, and with silver nitrate, to provide antibacterial protection against Staphylococcus aureus, a microorganism involved in prosthetic joint infections (PJIs). Field emission scanning electron microscopy (FESEM) showed that the samples were characterized by square-shaped macropores, and energy dispersive X-ray spectroscopy analysis confirmed the presence of PCL and BCP phases, while inductively coupled plasma-mass spectrometry (ICP-MS) established the release of Ag+ in the medium (~0.15-0.8 wt% of initial Ag content). Adhesion assays revealed a significant (p < 0.0001) reduction in both adherent and planktonic staphylococci on the Ag-functionalized biomaterials, and the presence of an inhibition halo confirmed Ag release from enriched samples. To assess the potential outcome in promoting bone integration, preliminary tests on sarcoma osteogenic-2 (Saos-2) cells indicated PCL and BCP/PCL biocompatibility, but a reduction in viability was observed for Ag-added biomaterials. Due to their combined biodegrading and antimicrobial properties, the silver-enriched BCP/PCL-based scaffolds showed good potential for engineering of bone tissue and for reducing PJIs as a microbial anti-adhesive tool used in the delivery of targeted antimicrobial molecules, even if the amount of silver needs to be tuned to improve osteointegration.

Gold clusters prevent breast cancer bone metastasis by suppressing tumor-induced osteoclastogenesis

Rationale: Bone is the most frequent site for breast cancer metastasis, which accounts for the leading cause of death in advanced breast cancer patients. Serious skeletal-related events (SREs) caused by bone metastasis have a decisive impact on the life expectancy of breast cancer patients, making breast cancer almost incurable. Metastatic breast cancer cell induced pathological osteoclastogenesis is a key driver of bone metastasis and osteolytic bone lesions. We previously reported that gold clusters can prevent inflammation induced osteoclastogenesis and osteolysis in vivo. In this study, we investigated the effects of a BSA-coated gold cluster on metastatic breast cancer-induced osteoclastogenesis in vitro and tumor-induced osteolysis in vivo, and elucidated its possible mechanism. Methods: Breast cancer cell line MDA-MB-231 was used to evaluate the regulatory effects of gold clusters on breast cancer metastasis and tumor induced osteoclastogenesis in vitro. Cell counting kit-8, transwell, wound-healing and colony formation assays were performed to evaluate the effect of gold clusters on proliferation and metastasis of MDA-MB-231 cells. Tartrate-resistant acid phosphatase (TRAP) staining and filamentous-actin rings analysis were used to detect the regulatory effects of gold clusters on MDA-MB-231 cell-conditioned medium (MDA-MB-231 CM) triggered and receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis in mouse bone marrow-derived mononuclear cells (BMMs). A mouse model of breast cancer bone metastasis was used to evaluate the in vivo activity of the gold cluster on the tumor induced osteolysis. Results: The gold clusters suppressed the migration, invasion and colony formation of MDA-MB-231 cells in a dose-dependent manner in vitro. The gold clusters strongly inhibited both MDA-MB-231 CM triggered and RANKL-induced osteoclast formation from BMMs in vitro. Cell studies indicated that the gold clusters suppressed the expression of osteolysis-related factors in MDA-MB-231 cells and inhibited the subsequent activation of NF-κB pathway in BMMs. Treatment with the clusters at a dose of 10 mg Au/kg.bw significantly reduces the breast cancer cell induced osteolysis in vivo. Conclusion: Therefore, the gold clusters may offer new therapeutic agents for preventing breast cancer bone metastasis and secondary osteolysis to improve patient outcomes.

Cancer- and Chemotherapy-Induced Musculoskeletal Degradation

Mobility in advanced cancer patients is a major health care concern and is often lost in advanced metastatic cancers. Erosion of mobility is a major component in determining quality of life but also starts a process of loss of muscle and bone mass that further devastates patients. In addition, treatment options become limited in these advanced cancer patients. Loss of bone and muscle occurs concomitantly. Advanced cancers that are metastatic to bone often lead to bone loss (osteolytic lesions) but may also lead to abnormal deposition of new bone (osteoblastic lesions). However, in both cases there is a disruption to normal bone remodeling and radiologic evidence of bone loss. Many antitumor therapies can also lead to loss of bone in cancer survivors. Bone loss releases cytokines (TGFβ) stored in the mineralized matrix that can act on skeletal muscle and lead to weakness. Likewise, loss of skeletal muscle mass leads to reduced bone mass and quality via mechanical and endocrine signals. Collectively these interactions are termed bone-muscle cross-talk, which has garnered much attention recently as a prime target for musculoskeletal health. Pharmacological approaches as well as nutrition and exercise can improve muscle and bone but have fallen short in the context of advanced cancers and cachexia. This review highlights our current knowledge of these interventions and discusses the difficulties in treating severe musculoskeletal deficits with the emphasis on improving not only bone mass and muscle size but also functional outcomes. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Metastatic bone disease of the pelvis and extremities: rationalizing orthopaedic treatment

BACKGROUND

Choosing the appropriate treatment for patients presenting with impending or pathological fractures is difficult and understanding the prognosis based on certain characteristics can help inform the decision to treat and construct to use in a palliative setting. We retrospectively analysed patients presenting with metastatic bone disease in the extremities and pelvis.

METHODS

Patients presenting with metastatic bone disease to the extremities or pelvis who underwent orthopaedic treatment from 1996 to 2012 were identified. Survival rates were calculated using life table analysis. Univariate and multivariate analysis was achieved with Cox proportional hazards regression.

RESULTS

There were a total of 462 patients. An overall 1-, 2- and 5-year survival rate of 45%, 29% and 13% was identified, respectively. In the multivariate analysis, preoperative haemoglobin was found to be an independent predictor of better survival while lung histotype, age, pathological fracture and previous combined therapy were negative predictors of survival. Patients undergoing prosthetic replacement had a significantly longer period of hospitalization in comparison to those undergoing internal fixation.

CONCLUSION

This study has contributed to our understanding of the survival rate and survival prognostication for patients presenting for orthopaedic treatment of metastatic bone disease.

Image-guided cryoablation for the treatment of painful musculoskeletal metastatic disease: a single-center experience

PURPOSE

The role of image-guided thermal ablation techniques for the nonoperative local management of painful osseous metastatic disease has expanded during recent years, and several advantages of cryoablation in this setting have emerged. The purpose of this study is to retrospectively evaluate and report a single-center experience of CT-guided percutaneous cryoablation in the setting of painful musculoskeletal metastatic disease.

METHODS

This study was approved by the institutional review board and is compliant with the Health Insurance Portability and Accountability Act. Electronic medical records of all patients who underwent percutaneous image-guided palliative cryoablation at our institution were reviewed (n = 61). An intent-to-treat analysis was performed. Records were reviewed for demographic data and anatomical data, primary tumor type, procedure details, and outcome-including change in analgesic requirements (expressed as morphine equivalent dosages), pain scores (utilizing the clinically implemented visual analog scale), subsequent therapies (including radiation and/or surgery), and complications during the 24 h following the procedure and at 3 months. Patients were excluded (n = 7) if data were not retrospectively identifiable at the defined time points.

RESULTS

Fifty-four tumors were ablated in 50 patients. There were statistically significant decreases in the median VAS score and narcotic usage at both 24 h and 3 months (p < 0.000). Six patients (11%) incurred complications related to their therapy. Two patients had no relief at 24 h, of which both reported worsened pain at 3 months. One patient had initial relief but symptom recurrence at 3 months. Four patients went on to have radiation therapy of the ablation site at some point following the procedure.

CONCLUSIONS

CT-guided cryoablation is a safe, effective, reproducible procedural option for the nonoperative local treatment of painful musculoskeletal metastatic disease.

Oligometastatic breast cancer: a shift from palliative to potentially curative treatment?

A distinctive subset of metastatic breast cancer is represented by the so called 'oligometastatic' disease, characterized by single/few detectable metastatic lesions. A more aggressive multidisciplinary approach can be considered in this patient population: available data report favorable results of 'radical' local therapy for limited metastatic disease at least in a subset of selected patients. Selection bias and the retrospective nature of data do not allow for generalization of the results: the use of such approaches must be individualized and managed within a multidisciplinary team of dedicated specialists. Improvement in surgical and radiation techniques, development of new tools to deliver local chemotherapy, and new procedures (i.e. cryosurgery, laser and microwave ablation) mandate careful evaluation of such single and combined modalities in controlled clinical trials. A more accurate identification of patients with limited metastases and better definition of treatment endpoints will also allow correct patient selection for locally aggressive therapies. This paper focusses on local treatment of the primary tumor and of the most frequent distant disease sites in the presence of oligometastatic disease.

Bone metastases in breast cancer: Frequency, metastatic pattern and non-systemic locoregional therapy

BACKGROUND

The study evaluates the frequency of and indications for bone-metastases (BM)-related surgery and/or radiotherapy in the palliative breast cancer (BC) situation and analyzes in which phase of the palliative disease course surgery and/or radiotherapy was applied.

METHODS

340 patients who developed distant metastatic disease (DMD) and died (i.e. patients with completed disease courses) were analyzed.

RESULTS

From the entire study cohort, 237 patients (69.7%) were diagnosed with BM. Out of these, 116 patients (48.9%) received BM-related radiotherapy and/or surgery during the palliative situation.

RADIOTHERAPY

108 patients (45.6%) received 161 series (range: 1-5) with 217 volumina (range: 1-8) on 300 osseous sites. At 75.3% of the radiated sites, the spine was the most frequent radiated location. Eighty-eight series (54.7%) were performed in the first third of the metastatic disease survival (MDS) period. The median survival after radiotherapy was 14 months (range: 0.2-121 months).

SURGERY

In 37 patients (15.6%), 50 procedures (range: 1-4) were necessary to stabilize BM. The femur predominated with 56.0% of the procedures. Twenty procedures (40.0%) were performed in the first third of survival follow-up. The median survival after surgery was 13.5 months (range: 0.5-49 months). BC patients with BM had a significantly improved MDS when radiotherapy and/or surgery for skeletal metastases was embedded in the palliative approach (27.5 months vs. 19.5 months, p<0.001). From the 118 patients who had a MDS of ≥24 months, the majority (54.2%) had BM-related radiotherapy and/or surgery during the palliative course.

CONCLUSIONS

Metastatic BC has become increasingly viewed as a chronic disease process. In a general palliative therapy approach, which allows for treatment according to the principles of a chronic disease, non-systemic therapy for BM, in particular radiotherapy, has a clearly established role in the therapy concept.

Biomaterial scaffolds for treating osteoporotic bone

Healing fractures resulting from osteoporosis or cancer remains a significant clinical challenge. In these populations, healing is often impaired not only due to age and disease, but also by other therapeutic interventions such as radiation, steroids, and chemotherapy. Despite substantial improvements in the treatment of osteoporosis over the last few decades, osteoporotic fractures are still a major clinical challenge in the elderly population due to impaired healing. Similar fractures with impaired healing are also prevalent in cancer patients, especially those with tumor growing in bone. Treatment options for cancer patients are further complicated by the fact that bone anabolic therapies are contraindicated in patients with tumors. Therefore, many patients undergo surgery to repair the fracture, and bone grafts are often used to stabilize orthopedic implants and provide a scaffold for ingrowth of new bone. Both synthetic and naturally occurring biomaterials have been investigated as bone grafts for repair of osteoporotic fractures, including calcium phosphate bone cements, resorbable polymers, and allograft or autograft bone. In order to re-establish normal bone repair, bone grafts have been augmented with anabolic agents, such as mesenchymal stem cells or recombinant human bone morphogenetic protein-2. These developing approaches to bone grafting are anticipated to improve the clinical management of osteoporotic and cancer-induced fractures.

Incidence, consequences and treatment of bone metastases in breast cancer patients-Experience from a single cancer centre

Background

There is a paucity of literature about the benefits of bone-targeted agents for breast cancer patients with bone metastases treated in the non-trial setting. We explored the incidence, consequences, and treatment of bone metastases at a single cancer centre.

Methods

Electronic records of metastatic breast cancer patients were reviewed and pertinent information was extracted.

Results

Of 264 metastatic breast cancer patients, 195 (73%) developed bone metastases. Of these patients, 176 were eligible for analysis. Median age at bone metastases diagnosis was 56.9 years (IQR 48–67) and initial presentation of bone metastases included asymptomatic radiological findings (58%), bone pain (40%), or a SRE (12.5%). Most patients (88%) received a bone-targeted agent, starting a median of 1.5 months (IQR 0.8–3.30) after bone metastasis diagnosis. 62% of patients had ≥1 SRE. The median time from bone metastasis diagnosis to first SRE was 1.8 months (IQR 0.20–8.43 months). Median number of SREs per patient was 1.5 (IQR 0–3). Overall, 26.8% of all SREs were clinically asymptomatic. Within the entire cohort, 51% required opioids and 20% were hospitalized due to either an SRE or bone pain.

Conclusions

Despite extensive use of bone-targeted agents, the incidence of SREs remains high. Nearly half of SREs occur prior to starting a bone-targeted agent. Use of opioids and hospitalizations secondary to bone metastases remain common. More effective treatment options are clearly needed.

Disease-related surgery in patients with distant metastatic breast cancer

INTRODUCTION

This study evaluates the frequency of and indications for disease-related surgical procedures in the palliative breast cancer (BC) situation.

PATIENTS & METHODS

Based on a cohort of women who were treated for newly diagnosed BC during a 20-year period (1990-2009), we analyzed 340 patients who developed distant metastatic disease (DMD) until 2011 and died (i.e. still ongoing palliative disease courses were not included).

RESULTS

One hundred and twenty-seven surgical procedures were performed in 100 patients (29.4% of all patients with metastatic disease). The most common site for surgery was breast (n = 60, 47.2%). The primary tumor was removed at first diagnosis of DMD in 43 patients (33.9%); sixteen operations (12.6%) were performed for local recurrence. In 37 patients, 50 surgical procedures (39.4%) were necessary to stabilize osseous structures due to metastases. Procedures were rarely performed on other common metastatic sites: lung: n = 1 (0.8%); liver: n = 1 (0.8%), brain: n = 4 (3.1%). When excluding surgery for primary breast tumors at initial diagnosis of DMD from analysis, 34 of 84 surgeries (40.4%) were performed in the first third of survival follow-up (i.e. period of metastatic disease survival); operations in the last two-thirds each totaled 29.8% (n = 25). The median survival after surgery was 16 months (range: 0.5-89 months).

CONCLUSIONS

In a cohort of BC patients who had primary or developed secondary DMD, nearly one third of the patients received disease-related surgical procedures during their palliative disease course. This high rate of operations shows that surgery has a clearly established role in the palliative therapy concept.