Skeletal complications of breast cancer therapies

Steroid metabolism and hormonal dynamics in normal and malignant ovaries

The ovaries are key steroid hormone production sites in post-pubertal females. However, current research on steroidogenic enzymes, endogenous hormone concentrations and their effects on healthy ovarian function and malignant development is limited. Here, we discuss the importance of steroid enzymes in normal and malignant ovaries, alongside hormone concentrations, receptor expression and action. Key enzymes include STS, 3β-HSD2, HSD17B1, ARK1C3, and aromatase, which influence ovarian steroidal action. Both androgen and oestrogen action, via their facilitating enzyme, drives ovarian follicle activation, development and maturation in healthy ovarian tissue. In ovarian cancer, some data suggest STS and oestrogen receptor α may be linked to aggressive forms, while various oestrogen-responsive factors may be involved in ovarian cancer metastasis. In contrast, androgen receptor expression and action vary across ovarian cancer subtypes. For future studies investigating steroidogenesis and steroidal activity in ovarian cancer, it is necessary to differentiate between disease subtypes for a comprehensive understanding.

CircMMP2(6,7) Cooperates with β-Catenin and PRMT5 to Disrupt Bone Homeostasis and Promote Breast Cancer Bone Metastasis

The bone is the most common site of distant metastasis of breast cancer, which leads to serious skeletal complications and mortality. Understanding the mechanisms underlying breast cancer bone metastasis would provide potential strategies for the prevention and treatment of breast cancer bone metastasis. In this study, we identified a circular RNA that we named circMMP2(6,7) that was significantly upregulated in bone metastatic breast cancer tissues and correlated with breast cancer-bone metastasis. Upregulation of circMMP2(6,7) dramatically enhanced the metastatic capability of breast cancer cells to the bone via inducing bone metastatic niche formation by disrupting bone homeostasis. Mechanistically, circMMP2(6,7) specifically bound to the promoters of bone-remodeling factors calcium-binding protein S100A4 and carbohydrate-binding protein LGALS3 and formed a complex with β-catenin and arginine methyltransferase PRMT5, eliciting histone H3R2me1/H3R2me2s-induced transcriptional activation. Treatment with GSK591, a selective PRMT5 inhibitor, effectively inhibited circMMP2(6,7)/β-catenin/PRMT5 complex-induced breast cancer bone metastasis. These findings reveal a role for circMMP2(6,7) in bone homeostasis disruption and shed light on the mechanisms driving breast cancer bone metastasis.

SIGNIFICANCE

Upregulation of bone-remodeling factors S100A4 and LGALS3 mediated by a circMMP2(6,7)/β-catenin/PRMT5 complex generates a niche that supports breast cancer bone metastasis, identifying PRMT5 as a promising target for treating metastasis.

Study of linear energy transfer effect on rib fracture in breast patients receiving pencil-beamscanning proton therapy

Purpose

To study the effect of proton linear energy transfer (LET) on rib fracture in breast cancer patients treated with pencil-beam scanning proton therapy (PBS) using a novel tool of dose-LET volume histogram (DLVH).

Methods

From a prospective registry of patients treated with post-mastectomy proton therapy to the chest wall and regional lymph nodes for breast cancer between 2015 and 2020, we retrospectively identified rib fracture cases detected after completing treatment. Contemporaneously treated control patients that did not develop rib fracture were matched to patients 2:1 considering prescription dose, boost location, reconstruction status, laterality, chest wall thickness, and treatment year.The DLVH index, V(d, l), defined as volume(V) of the structure with at least dose(d) and LET(l), was calculated. DLVH plots between the fracture and control group were compared. Conditional logistic regression (CLR) model was used to establish the relation of V(d, l) and the observed fracture at each combination of d and l. The p-value derived from CLR model shows the statistical difference between fracture patients and the matched control group. Using the 2D p-value map derived from CLR model, the DLVH features associated with the patient outcomes were extracted.

Results

Seven rib fracture patients were identified, and fourteen matched patients were selected for the control group. The median time from the completion of proton therapy to rib fracture diagnosis was 12 months (range 5 to 14 months). Two patients had grade 2 symptomatic rib fracture while the remaining 5 were grade 1 incidentally detected on imaging. The derived p-value map demonstrated larger V(0-36Gy[RBE], 4.0-5.0 keV/μm) in patients experiencing fracture (p<0.1). For example, the p value for V(30 Gy[RBE], 4.0 keV/um) was 0.069.

Conclusions

In breast cancer patients receiving PBS, a larger volume of chest wall receiving moderate dose and high LET may result in increased risk of rib fracture.

Role of Body Composition in the Prediction of Skeletal Fragility Induced by Hormone Deprivation Therapies in Cancer Patients

PURPOSE OF REVIEW

This review paper is intended to show that changes in body composition are key in the pathogenesis of bone fragility amongst patients with breast and prostate cancer receiving hormone deprivation therapies (HDTs) and that the mechanism is based on the development of alterations in bone quality rather than in bone quantity.

RECENT FINDINGS

Preclinical and clinical data suggest a tight connection amongst bone, adipose and muscular tissues by means of several soluble mediators, potentially leading to (1) bone resorption and bone quality deterioration in sarcopenic obese subjects, (2) bone mineral deposition in healthy trained subjects. Cancer patients treated with HDTs frequently fall into the first condition, named osteosarcopenic obesity. Current clinical guidelines for the prevention of treatment-induced osteoporosis focus on bone mineral density (BMD) as a main predictive factor for fracture risk; however, the pathophysiology underlying HDT-induced bone fragility differs from that of primary and postmenopausal osteoporosis, suggesting a prevalent role for bone quality alterations. Focusing on available data from clinical trials, in our review we suggest osteosarcopenic obesity as a common target for the prevention and treatment of HDTs-related metabolic and skeletal complications, beyond a BMD-centred approach.

Endocrine sequelae of hematopoietic stem cell transplantation: Effects on mineral homeostasis and bone metabolism

Hematopoietic stem cell transplantation (HSCT) is an established therapeutic strategy for the treatment of malignant (leukemia and lymphoma) and non-malignant (thalassemia, anemia, and immunodeficiency) hematopoietic diseases. Thanks to the improvement in patient care and the development of more tolerable conditioning treatments, which has extended the applicability of therapy to the elderly, a growing number of patients have successfully benefited from HSCT therapy and, more importantly, HSCT transplant-related mortality has consistently reduced in recent years. However, concomitantly to long term patient survival, a growing incidence of late HSCT-related sequelae has been reported, being variably associated with negative effects on quality of life of patients and having a non-negligible impact on healthcare systems. The most predominantly observed HSCT-caused complications are chronic alterations of the endocrine system and metabolism, which endanger post-operative quality of life and increase morbidity and mortality of transplanted patients. Here, we specifically review the current knowledge on HSCT-derived side-effects on the perturbation of mineral metabolism; in particular, the homeostasis of calcium, focusing on current reports regarding osteoporosis and recurrent renal dysfunctions that have been observed in a percentage of HSC-transplanted patients. Possible secondary implications of conditioning treatments for HSCT on the physiology of the parathyroid glands and calcium homeostasis, alone or in association with HSCT-caused renal and bone defects, are critically discussed as well.

Assessment of DXA derived bone quality indexes and bone geometry parameters in early breast cancer patients: A single center cross-sectional study

Background

Bone mineral density (BMD) lacks sensitivity in individual fracture risk assessment in early breast cancer (EBC) patients treated with aromatase inhibitors (AIs). New dual-energy X-ray absorptiometry (DXA) based risk factors are needed.

Methods

Trabecular bone score (TBS), bone strain index (BSI) and DXA parameters of bone geometry were evaluated in postmenopausal women diagnosed with EBC. The aim was to explore their association with morphometric vertebral fractures (VFs). Subjects were categorized in 3 groups in order to evaluate the impact of AIs and denosumab on bone geometry: AI-naive, AI-treated minus (AIDen-) or plus (AIDen+) denosumab.

Results

A total of 610 EBC patients entered the study: 305 were AI-naive, 187 AIDen-, and 118 AIDen+. In the AI-naive group, the presence of VFs was associated with lower total hip BMD and T-score and higher femoral BSI. As regards as bone geometry parameters, AI-naive fractured patients reported a significant increase in femoral narrow neck (NN) endocortical width, femoral NN subperiosteal width, intertrochanteric buckling ratio (BR), intertrochanteric endocortical width, femoral shaft (FS) BR and endocortical width, as compared to non-fractured patients. Intertrochanteric BR and intertrochanteric cortical thickness significantly increased in the presence of VFs in AIDen- patients, not in AIDen+ ones. An increase in cross-sectional area and cross-sectional moment of inertia, both intertrochanteric and at FS, significantly correlated with VFs only in AIDen+. No association with VFs was found for either lumbar BSI or TBS in all groups.

Conclusions

Bone geometry parameters are variably associated with VFs in EBC patients, either AI-naive or AI treated in combination with denosumab. These data suggest a tailored choice of fracture risk parameters in the 3 subgroups of EBC patients.

Incidence of Rib Fracture following Treatment with Proton Therapy for Breast Cancer

Purpose

To determine the rib fracture rate in a cohort of patients with breast cancer treated with proton therapy.

Patient and Methods

From a prospective database, we identified 225 patients treated with proton therapy between 2012 and 2020 (223 women; 2 men). Clinical and dosimetric data were extracted, the cumulative incidence method assessed rib fracture rate, and Fine-Gray tests assessed prognostic significance of select variables. In-field rib fracture was defined as a fracture that occurred in a rib located within the 10% isodose line. Out-of-field rib fracture was defined as a fracture occurring in a rib location outside of the 10% isodose line.

Results

Of the patients, 74% had left-sided breast cancer; 5%, bilateral; and 21%, right-sided. Dual-energy x-ray absorptiometry scans showed normality in 20%, osteopenia in 34%, and osteoporosis in 6% (test not performed in 40%). Additionally, 57% received an aromatase inhibitor. Target volumes were breast ± internal mammary nodes (IMNs) (16%), breast and comprehensive regional lymphatics (32%), chest wall ± IMNs (1%), and chest wall/comprehensive regional lymphatics (51%). Passive-scattered proton therapy was used for 41% of patients, 58% underwent pencil-beam scanning (PBS), and 1% underwent a combination (passive scattering/PBS), with 85% of patients receiving a boost. Median follow-up was 3.1 years, with 97% having >12-month follow-up. The 3-year cumulative in-field rib fracture incidence was 3.7%. Eight patients developed in-field rib fractures (1 symptomatic, 7 imaging identified) for a 0.4% symptomatic rib fracture rate. Median time from radiation completion to rib fracture identification was 1.8 years (fractures were identified within 2.2 years for 7 of 8 patients). No variables were associated with rib fracture on univariate analysis. Three fractures developed outside the radiation field (0.9% cumulative incidence of out-of-field rib fracture).

Conclusion

In this series of patients with breast cancer treated with proton therapy, the 3-year rib fracture rates remain low (in-field 3.7%; symptomatic 0.4%). As in photon therapy, the asymptomatic rate may be underestimated owing to a lack of routine surveillance imaging. However, patients experiencing symptomatic rib fractures after proton therapy for breast cancer are rare.

Effect of Degarelix Administration on Bone Health in Prostate Cancer Patients Without Bone Metastases. The Blade Study

CONTEXT

As patients are now living with prostate cancer for longer, the long-term impact of hormonal treatment on bone health is an increasingly debated subject.

OBJECTIVE

To characterize the changes in bone mineral density (BMD) and bone turnover markers after degarelix administration in prostate cancer patients without bone metastases. To explore the predictive role of body composition on treatment induced bone loss.

METHODS

BMD and body composition (lean body mass, fat body mass, and appendicular mass index [ALMI]) were assessed by dual X-ray absorptiometry on study entry and after 12 months of degarelix therapy. Alkaline phosphate (ALP) and C-terminal telopeptide of type I collagen (CTX) were assessed at baseline, and 6 and 12 months.

RESULTS

Twenty-nine patients entered the study. Degarelix administration was associated with a significant decrease in BMD after 12 months (2.4% reduction from baseline at lumbar spine). Serum CTX and ALP increased significantly (median increase from baseline 99% and 19.3%, respectively). An inverse correlation was observed between ALMI and CTX, but not ALP, at both baseline (Pearson r = -0.62, P < .0001) and month 12 (Pearson r = -0.41, P = .032). Moreover, a significant inverse correlation between changes in ALMI and CTX at 12 months (Pearson r = -0.43, P = .019) and a direct relationship between changes of ALMI and ALP (Pearson r = 0.44, P = .016) during degarelix therapy were observed.

CONCLUSION

Degarelix administration is associated with a significant decrease in BMD and increase in bone turnover markers. ALMI is a promising predictor of bone loss in prostate cancer patients receiving androgen deprivation therapy, and ALMI changes during therapy are associated with bone turnover derangement favoring bone quality alterations.

Effect of d-limonene and its derivatives on breast cancer in human trials: a scoping review and narrative synthesis

BACKGROUND

D-limonene and its derivatives have demonstrated potential chemopreventive and anticancer activity in preclinical and clinical studies. The aim of this scoping review was to assess and critically appraise current literature on the effect of these bioactive citrus peel compounds on breast cancer in human trials and to identify knowledge gaps for exploration in future studies.

METHODS

This study followed a scoping review framework. Peer-reviewed journal articles were included if they reported the effect of d-limonene or its derivatives on breast cancer in human subjects. Articles were retrieved from academic databases - PubMed, EMBASE, CINAHL, Web of Science, and Cochrane reviews - and iteratively through review of bibliographies of relevant manuscripts. Titles and abstracts were appraised against the aforementioned inclusion criteria in a first round of screening. Through consensus meetings and full article review by authors, a final set of studies were selected. Results were reported according to the PRISMA extension for scoping reviews.

RESULTS

Our search strategy yielded 367 records. Following screening and adjudication, five articles reporting on phase 1(n = 2), phase 2 (n = 2) and both trial phases (n = 1) were included as the final dataset for this review. Trials evaluating the effect of d-limonene (n = 2) showed it was well tolerated in subjects. One study (n = 43 participants) showed d-limonene concentrated in breast tissue (mean 41.3 μg/g tissue) and reduction in tumor cyclin D1 expression, which is associated with tumor proliferation arrest. This study did not show meaningful change in serum biomarkers associated with breast cancer, except for a statistically significant increase in insulin-like growth factor-1 (IGF-I) levels. While elevation of IGF-I is associated with increased cancer risk, the clinical implication of this study remains uncertain given its short duration. Trials with perillyl alcohol (n = 3) showed low tolerance and no effect on breast cancer.

CONCLUSION

This review demonstrated a dearth of clinical studies exploring the effect of d-limonene and its derivatives on breast cancer. Limited literature suggests d-limonene is safe and tolerable in human subjects compared to its derivative, perillyl alcohol. Our review demonstrates the need for additional well-powered placebo-controlled trials that assess d-limonene's efficacy on breast cancer compared to other therapies.

Effects of Medical Treatment of Prostate Cancer on Bone Health

Medical treatment of prostate cancer (PC) is multidisciplinary, resulting in prolonged survival. Androgen-deprivation therapy (ADT) can have negative effects on skeletal metabolism, particularly if combined with glucocorticoids. We discuss the pathophysiology and effects of ADT and glucocorticoids on skeletal endpoints, as well as the awareness and management of bone fragility. Coadministration of glucocorticoids is necessary with abiraterone because this causes a novel acquired form of 17-hydroxylase deficiency and synergistically increases the risk of fracture by affecting bone quality. Bone antiresorptive agents [selective estrogen receptor modulators (SERMS), bisphosphonates, and denosumab] increase bone mineral density (BMD) and in some instances reduce fracture risk in PC patients on ADT. Awareness and management of bone health in PC can be improved by integrating endocrinologists into the multidisciplinary PC team.

Risk Factors for Hematopoietic Stem Cell Transplantation-Associated Bone Loss

Hematopoietic stem cell transplantation (HSCT), including bone marrow transplantation, is the treatment of choice for many hematologic diseases, including hematologic malignancies and different types of anemia. The use of HSCT is increasing annually, mainly because advanced research that has been conducted in this area has exponentially expanded the indications for HSCT and significantly improved transplantation techniques and supportive care practices. Collectively, these improvements have led to an increase in the overall survival of HSCT patients. However, as post-HSCT survival is increasing, awareness of the potential late complications of HSCT is also growing. Unpredictable bone loss is one of the major post-HSCT complications that can cause significant morbidity and impair the quality of life of survivors. Although the exact mechanism of post-HSCT bone loss is not yet known, previous studies have suggested that numerous factors, including destructive preparative regimens (eg, high-dose chemotherapy, total body irradiation), treatment-related complications (eg, graft-versus-host disease), endocrine abnormalities (eg, diabetes mellitus, thyroid dysfunction, adrenal insufficiency), lack of physical activity, and the underlying disease itself are responsible for HSCT-associated bone loss. Sufficient data have been collected to suggest that post-HSCT bone loss can be prevented and treated using the same preventive and treatment modalities as used for the general population. Various guidelines have been formulated to help keep a check on HSCT recipients' deteriorating bone health.

The Interaction of Lean Body Mass With Fat Body Mass Is Associated With Vertebral Fracture Prevalence in Women With Early Breast Cancer Undergoing Aromatase Inhibitor Therapy

Aromatase inhibitors (AIs) induce depletion of estrogen levels, causing bone loss and increased fracture risk in women with breast cancer. High‐fat body mass (FBM) emerged as an independent factor associated with the prevalence of morphometric vertebral fractures (VFs) in patients undergoing AIs. We explored the role of lean body mass (LBM) and the interaction of LBM with FBM in predicting the occurrence of VFs in postmenopausal women who were either AI‐naïve or AI‐treated. A total of 684 consecutive breast cancer patients were enrolled in this cross‐sectional study. Each woman underwent a dual‐energy X‐ray absorptiometry (DXA) scan, measuring bone mineral density (BMD), LBM, and FBM; VFs were assessed using a quantitative morphometric analysis of DXA images. After propensity score matching, the study population was restricted to 480 women, 240 AI‐naïve and 240 AI‐treated. We used multivariable logistic regression models to explore the associations between baseline characteristics, VF prevalence and the interaction between LBM, FBM and AI therapy. No interaction between LBM and AI therapy on VF prevalence was shown. Conversely, we reported a significant interaction between LBM, FBM and AI therapy (p = .0311). Among AI‐treated women having LBM below and FBM above or equal the median value, VF prevalence was numerically higher (15/31; 48.4%) than in other subgroups (VF prevalence: 35.7% in high‐LBM and low‐FBM group, 23.2% in high‐LBM and high‐FBM group, and 19.8% in low‐LBM and low‐FBM group). Among AI‐naïve women, the greatest VF proportion was observed in the subgroup with LBM and FBM below median value (25/92; 27.2%). This study suggests a synergism between LBM and FBM in predicting the morphometric VF in women with early breast cancer undergoing AIs. This observation is new and deserves further investigation. The assessment of body composition by DXA might be useful when estimating fracture risk in this population. © 2020 American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Role of tumor-derived exosomes in bone metastasis

Tight coupling between bone resorption and formation is essential for bone remodeling. Disruption of this equilibrium can lead to skeletal disorders. Osseous metastatic disease is a severe consequence of tumor cell dissemination from numerous primary cancer sites, including the prostate, lungs and breasts. Metastatic disease is one of the most common causes of mortality in patients with cancer. Rapid advances in the therapeutic options for bone disease, including the use of bisphosphonates, have achieved effective clinical effects. However, the overall survival time of patients with bone metastatic has not significantly improved. Exosomes, which originate from tumor tissue and preferentially the bone, provide a reasonable way to understand the mechanism of neoplastic bone metastasis. Recently, several studies have indicated that tumor-derived exosomes are involved in cancer progression. However, the potential role that exosomes serve in the pathological communication between tumor and bone cells within the skeletal microenvironment remains an emerging field. The present review reports some recent findings on the detrimental roles of exosomes in bone metastasis. In addition, since exosomes are involved in metabolic organ cross-talk, this review highlights the involvement of cancer-derived exosomes in the regulation of skeletal metastatic diseases. Lastly, the potential promising clinical applications and emerging therapeutic opportunities targeting exosomes are discussed as novel strategies for cancer therapy.

Survivorship issues in older breast cancer survivors

PURPOSE

Almost half of breast cancer survivors are aged ≥ 65 years and the proportion is likely to increase due to the aging of the population. The objectives of this article were to review studies of health outcomes among older breast cancer survivors ≥ 65 years to identify gaps in the published literature and offer suggestions for future research.

METHODS

The present review is based upon bibliographic searches in PubMed and CINAHL and relevant search terms. Articles published in English from January 1, 1970 through October 1, 2018 were identified using the following MeSH search terms and Boolean algebra commands.

RESULTS

This review has revealed that older breast cancer survivors cope with health issues related to cancer treatment and the aging process, including comorbidities, osteoporosis, symptoms, physical functioning, cognitive functioning, nutrition, and physical activity.

CONCLUSIONS

Additional research is needed to examine therapeutic interventions to address the health conditions older breast cancer survivors are coping with. Particular focus of further research should be on the nutritional status and physical activity levels of older breast cancer survivors. Individualized nutrition plans and tailored physical activity programs for older survivors are needed that meet people where they are and that form habits.

The effects of high-dose calcitriol and individualized exercise on bone metabolism in breast cancer survivors on hormonal therapy: a phase II feasibility trial

INTRODUCTION

Cancer treatment-induced bone loss (CTIBL) is a long-term side effect of breast cancer therapy. Both calcitriol and weight-bearing exercise improve bone metabolism for osteoporotic patients, but are unproven in a breast cancer population. We used a novel high-dose calcitriol regimen with an individualized exercise intervention to improve bone metabolism in breast cancer survivors.

METHODS

We accrued 41 subjects to this open label, 2 × 2 factorial, randomized feasibility trial. Breast cancer survivors were randomized to receive the following: (1) calcitriol (45 micrograms/week), (2) individualized exercise with progressive walking and resistance training, (3) both, or (4) a daily multivitamin (control condition) for 12 weeks. Primary outcomes included changes in biomarkers of bone formation, bone resorption, and the bone remodeling index, a composite measure of bone formation and resorption. Safety measures included clinical and biochemical adverse events. A main effect analysis was used for these endpoints.

RESULTS

Hypercalcemia was limited to three grade I cases with no grade ≥ 2 cases. Among exercisers, 100% engaged in the prescribed aerobic training and 44.4% engaged in the prescribed resistance training. Calcitriol significantly improved bone formation (Cohen's d = 0.64; p < 0.01), resulting in a non-significant increase in the bone remodeling index (Cohen's d = 0.21; p = 31). Exercise failed to improve any of the bone biomarkers.

CONCLUSIONS

Both calcitriol and exercise were shown to be feasible and well tolerated. Calcitriol significantly improved bone formation, resulting in a net increase of bone metabolism. Compliance with the exercise intervention was sub-optimal, which may have led to a lack of effect of exercise on bone metabolism.

Exercise for Toxicity Management in Cancer-A Narrative Review

Although the treatment of cancer is more effective now than ever, patients with cancer still face acute and chronic toxicities such as fatigue, cardiotoxicity, pain, cognitive impairment, and neurotoxicity. In this narrative review, we briefly discuss the use of exercise for toxicity management in patients with cancer, biological mechanisms underlying the toxicities and the effects of exercise, barriers that patients- especially underserved patients-face in adopting and adhering to exercise programs, and new technologies to overcome barriers to exercise. Our conclusions and clinical suggestions are: (1) exercise is safe and effective for treating many toxicities; (2) patients can benefit from a variety of exercise modalities (e.g., walking, cycling, resistance bands, yoga); (3) exercise should be started as soon as possible, even before treatments begin; (4) exercise should be continued as long as possible, as a lifestyle; and (5) barriers to exercise should be identified and addressed, (e.g., continually encouraging patients to exercise, using mobile technology, advocating for safe communities that encourage active lifestyles). Future research should inform definitive clinical guidelines for the use of exercise to ameliorate toxicities from cancer and its treatment.

[Antihormonal therapy in prostate cancer : Side effects]

Androgen deprivation is still standard therapy for prostate cancer, either as primary androgen deprivation therapy or with the use of secondary hormonal drugs including abiraterone and enzalutamide. However, especially the clinically occult side effects like metabolic changes or cardiovascular complications and effects on the psyche of the patient are often not recognized in daily practice. Active monitoring of such side effects is essential for prevention and early intervention. In addition, the efficacy of androgen deprivation therapies is limited by primary and secondary resistance. The underlying molecular mechanism including splice variants of the androgen receptor in contrast to mutations are usually reversible and should be regarded as a sign of efficacy of the current treatment. Therefore, the clever, timely use of androgen deprivation or even the use of a bipolar androgen therapy should enable reversal of resistance to again render tumor cells sensitive to androgen-deprivation therapy.

Bone: A Fertile Soil for Cancer Metastasis

Bone is one of the most common and most dangerous sites for metastatic growth across cancer types, and bone metastasis remains incurable. Unfortunately, the processes by which cancers preferentially metastasize to bone are still not well understood. In this review, we summarize the morphological features, physical properties, and cell signaling events that make bone a unique site for metastasis and bone remodeling. The signaling crosstalk between the tumor cells and bone cells begins a vicious cycle - a self-sustaining feedback loop between the tumor cells and the bone microenvironment composed of osteoclasts, osteoblasts, other bone marrow cells, bone matrix, and vasculature to support both tumor growth and bone destruction. Through this crosstalk, bone provides a fertile microenvironment that can harbor dormant tumor cells, sometimes for long periods, and support their growth by releasing cytokines as the bone matrix is destroyed, similar to providing nutrients for a seed to germinate in soil. However, few models exist to study the late stages of bone colonization by metastatic tumor cells. We describe some of the current methodologies used to study bone metastasis, highlighting the limitations of these methods and alternative future strategies to be used to study bone metastasis. While <i>in vivo</i> animal and patient studies may provide the gold standard for studying metastasis, <i>ex vivo</i> models can be used as an alternative to enable more controlled experiments designed to study the late stages of bone metastasis.

Fat fraction estimation of morphologically normal lumbar vertebrae using the two-point mDixon turbo spin-echo MRI with flexible echo times and multipeak spectral model of fat: Comparison between cancer and non-cancer patients

PURPOSE

This study aims to compare fat fraction of lumbar vertebrae between cancer and non-cancer patients, using the two-point modified Dixon (mDixon) turbo spin-echo (TSE) MRI with flexible echo times and multipeak fat spectral model.

MATERIALS AND METHODS

Fat fraction was calculated from fat and water images reconstructed by the mDixon TSE technique. Fat fraction of fat-water phantoms measured with the mDixon TSE method was compared with actual fat percentages. Patients who had undergone mDixon spine MRI and dual-energy X-ray absorptiometry within one year and had no bone metastasis were divided into cancer (n=7) and non-cancer (n=23) groups. Fat fraction and bone mineral density (BMD) were compared between the two groups.

RESULTS

Fat fraction of phantoms measured with mDixon MRI was highly correlated with their actual fat percentages (P<0.01, R(2)=0.93). Fat fraction of lumbar vertebrae was significantly lower in cancer patients (58.27±3.16%) than in non-cancer patients (70.48±1.83%) (P<0.01). BMD was not different between cancer (0.912±0.057g/cm(2)) and non-cancer patients (0.876±0.032g/cm(2)) (P=0.58). Fat fraction and BMD showed no significant correlation (P=0.95, R=0.006).

CONCLUSIONS

A two-point mDixon TSE method for assessing fat fraction was reliable. Fat fraction of morphologically normal lumbar vertebrae was significantly lower in cancer patients compared to non-cancer patients, using the two-point mDixon TSE technique.

Association of osteoprotegerin and bone loss after adjuvant chemotherapy in early-stage breast cancer

PURPOSE

Chemotherapy induced ovarian failure (CIOF) results in rapid bone loss. Receptor Activator of Nuclear Factor Kappa-B (RANK)-RANK ligand (RANK-L) signaling balances bone resorption and formation. Osteoprotegerin (OPG) acts as a decoy receptor for RANK, interrupting osteoclast activation and bone resorption. This study examined the relationship between OPG and bone loss in women with CIOF.

METHODS

Premenopausal women with stage I/II breast cancers receiving adjuvant chemotherapy were evaluated at chemotherapy initiation, 6 and 12 months. Bone mineral density (BMD) at the lumbar spine (LS) and femoral neck (FN), follicle stimulating hormone (FSH), ionized calcium, osteocalcin, and OPG were serially measured. CIOF was defined as a negative pregnancy test, FSH levels >30 MIU/mL, and ≥3 months of amenorrhea.

RESULTS

Forty women were enrolled; 31 (77.5%) met CIOF criteria. BMD significantly decreased (p < 0.001) in the CIOF group at both time points: LS BMD decreased from a median of 0.993 g/cm(2) to 0.976 g/cm(2) and 0.937 g/cm(2) at 6 and 12 months, respectively. OPG was significantly elevated at 6 months (median increase 0.30 pmol/L, p = 0.015) and then decreased at 12 months to levels still above baseline (median difference 0.2 pmol/L, p = 0.70).

CONCLUSIONS

In what was likely a compensatory response to rapid bone loss, CIOF patients' OPG levels increased at 6 months and then decreased at 12 months to values greater than baseline assessments. This phenomenon is described in other diseases, but never before in CIOF.

Geriatric assessment as an aide to understanding falls in older adults with cancer

PURPOSE

In older adults, falls are a common cause of functional decline, institutionalization, and reduced quality of life. This study (1) investigates the prevalence of falls in a large sample of community-dwelling older adults with a cancer diagnosis and (2) evaluates the association of falls with domains of comprehensive geriatric assessment (CGA) that pertain to falls risk.

METHODS

Patients completed a CGA that includes a self-reported measure of number of falls in the past 6 months. Summary statistics are used to describe prevalence of falls and associations with hypothesized risk factors using Fisher's exact tests and multivariable logistic regression.

RESULTS

A total of 1172 patients were enrolled, mean age 73 (65-99), 74 % female, and 89 % Caucasian. Two hundred fifty-six (22 %) reported one or more falls within the last 6 months. Patients with at least one instrumental activities of daily living (IADL) or physical function deficit had more falls as compared those with no deficits identified (p ≤ 0.001). The number of daily medications, comorbidities, Timed Up and Go score >14 s, and poor vision were also associated with increased falls (p ≤ 0.001). Reduced physical function, poor vision, and low performance status had the highest adjusted odds ratio (3.6, 3.4, and 3.0, respectively) for falls.

CONCLUSIONS

There is a high prevalence of falls in community-dwelling older patients with a cancer diagnosis. Falls are significantly associated with several measures of geriatric assessment including IADL, physical function, comorbidities, medications, and vision. Timely identification and management of risk factors for falls are important considerations in the care of older cancer patients.

Parathyroid hormone linked to a collagen binding domain promotes hair growth in a mouse model of chemotherapy-induced alopecia in a dose-dependent manner

Chemotherapy-induced alopecia is a major source of psychological stress in patients undergoing cancer chemotherapy, and it can influence treatment decisions. Although there is currently no therapy for alopecia, a fusion protein of parathyroid hormone and collagen binding domain (PTH-CBD) has shown promise in animal models. The aim of this study was to determine whether there are dose-dependent effects of PTH-CBD on chemotherapy-induced alopecia in a mouse model. C57BL/6J mice were waxed to synchronize hair follicles; treated on day 7 with vehicle or PTH-CBD (100, 320, and 1000 mcg/kg subcutaneous injection); and treated on day 9 with vehicle or cyclophosphamide (150 mg/kg intraperitoneally). Mice were photographed every 3-4 days and killed on day 63 for histological analysis. Photographs were quantified by gray scale analysis to assess hair content. Mice not receiving chemotherapy showed regrowth of hair 2 weeks after waxing and normal histology after 2 months. Mice receiving chemotherapy alone showed marked hair loss after chemotherapy, which was sustained for 10 days and was followed by rapid regrowth of a normal coat. Histological analysis revealed rapid cycling dystrophic anagen/catagen follicles. Animals receiving chemotherapy and PTH-CBD showed decreased hair loss and more rapid regrowth of hair than that seen with chemotherapy alone (increased hair growth by gray scale analysis, P<0.05), and the effects were dose dependent. Histologically, hair follicles in animals receiving the highest dose of PTH-CBD were in a quiescent phase, similar to that in mice that did not receive chemotherapy. Single-dose subcutaneous administration of PTH-CBD showed dose-dependent effects in minimizing hair loss and speeding up recovery from chemotherapy-induced alopecia.

Bone health issues in breast cancer survivors: a Medicare Current Beneficiary Survey (MCBS) study

PURPOSE

Breast cancer treatments (chemotherapy and hormone therapy) can cause a rapid loss in bone mineral density, leading to osteoporosis and fractures later in life. Fortunately, preventative measures (vitamin D, exercise, etc.) can delay bone loss if employed early enough. This study compares the prevalence of osteoporosis and osteoporosis-related discussions with physicians among female breast cancer survivors and females with no cancer history to determine if breast cancer patients are being correctly advised on their high risk of bone loss.

METHODS

The 2003 Medicare Current Beneficiary Survey, a nationally representative sample of 550 women with a breast cancer history and 6,673 women with no cancer history aged ≥65, was used. The first set of dependent variables collected information on bone health (osteoporosis, falls, and fractures). The second set of dependent variables collected information on bone health discussions with their physician. Multivariate logistic regression models were used to evaluate whether breast cancer was independently associated with bone health issues.

RESULTS

After adjustment for confounders, a breast cancer diagnosis was found to be associated with a higher prevalence of an osteoporosis diagnosis over their lifetime (adjusted odds ratio (OR(adj)) = 1.32, 95 % confidence interval (95 % CI) = 1.08-1.61) and falls in the previous year (OR(adj) = 1.23, 95 % CI = 1.01-1.51) compared to respondents without a cancer diagnosis. However, breast cancer respondents were not more likely than respondents without a cancer diagnosis to discuss osteoporosis with their physician (OR(adj) = 1.20, 95 % CI = 0.96-1.50) or be told they are at high risk for osteoporosis (OR(adj) = 1.41, 95 % CI = 0.95-2.10).

CONCLUSIONS

A breast cancer diagnosis was associated with an increased prevalence of osteoporosis and falls. Nevertheless, breast cancer respondents were not more likely to discuss osteoporosis with their physician nor were they more likely to be considered high risk for osteoporosis. Increased dialogue between physician and breast cancer patient pertaining to bone loss is needed.

Calcium and vitamin D supplementation and loss of bone mineral density in women undergoing breast cancer therapy

An unintended consequence of breast cancer therapies is an increased risk of osteoporosis due to accelerated bone loss. We conducted a systematic review of calcium and/or vitamin D (Ca±D) supplementation trials for maintaining bone mineral density (BMD) in women with breast cancer using the "before-after" data from the Ca±D supplemented comparison group of trials evaluating the effect of drugs such as bisphosphonates on BMD. Whether Ca±D supplements increase BMD in women undergoing breast cancer therapy has never been tested against an unsupplemented control group. However, results from 16 trials indicate that the Ca±D doses tested (500-1500mg calcium; 200-1000IU vitamin D) were inadequate to prevent BMD loss in these women. Cardiovascular disease is the main cause of mortality in women with breast cancer. Because calcium supplements may increase cardiovascular disease risk, future trials should evaluate the safety and efficacy of Ca±D supplementation in women undergoing breast cancer therapy.

Selective tyrosine kinase inhibition of insulin-like growth factor-1 receptor inhibits human and mouse breast cancer-induced bone cell activity, bone remodeling, and osteolysis

Insulin-like growth factor 1 (IGF-1) plays an important role in both bone metabolism and breast cancer. In this study, we investigated the effects of the novel IGF-1 receptor tyrosine kinase inhibitor cis-3-[3-(4-methyl-piperazin-l-yl)-cyclobutyl]-1-(2-phenyl-quinolin-7-yl)-imidazo[1,5-a]pyrazin-8-ylamine (PQIP) on osteolytic bone disease associated with breast cancer. Human MDA-MB-231 and mouse 4T1 breast cancer cells enhanced osteoclast formation in receptor activator of NF-κB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) stimulated bone marrow cultures, and these effects were significantly inhibited by PQIP. Functional studies in osteoclasts showed that PQIP inhibited both IGF-1 and conditioned medium-induced osteoclast formation by preventing phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) activation without interfering with RANKL or M-CSF signaling. Treatment of osteoblasts with PQIP significantly inhibited the increase in RANKL/osteoprotegerin (OPG) ratio by IGF-1 and conditioned medium and totally prevented conditioned medium-induced osteoclast formation in osteoblast-bone marrow (BM) cell cocultures, thereby suggesting an inhibitory effect on osteoblast-osteoclast coupling. PQIP also inhibited IGF-1-induced osteoblast differentiation, spreading, migration, and bone nodule formation. Treatment with PQIP significantly reduced MDA-MB-231 conditioned medium-induced osteolytic bone loss in a mouse calvarial organ culture system ex vivo and in adult mice in vivo. Moreover, once daily oral administration of PQIP significantly decreased trabecular bone loss and reduced the size of osteolytic bone lesions following 4T1 intratibial injection in mice. Quantitative histomorphometry showed a significant reduction in bone resorption and formation indices, indicative of a reduced rate of cancer-associated bone turnover. We conclude that inhibition of IGF-1 receptor tyrosine kinase activity by PQIP suppresses breast cancer-induced bone turnover and osteolysis. Therefore, PQIP, and its novel derivatives that are currently in advanced clinical development for the treatment of a number of solid tumors, may be of value in the treatment of osteolytic bone disease associated with breast cancer.

Simultaneous integrated boost irradiation after breast-conserving surgery: physician-rated toxicity and cosmetic outcome at 30 months' follow-up

PURPOSE

To evaluate toxicity and cosmetic outcome (CO) in breast cancer survivors treated with three-dimensional conformal radiotherapy with a hypofractionated, simultaneous integrated boost (3D-CRT-SIB) and to identify risk factors for toxicity, with special focus on the impact of age.

METHODS AND MATERIALS

Included were 940 consecutive disease-free patients treated for breast cancer (Stage 0-III) with 3D-CRT-SIB, after breast-conserving surgery, from 2005 to 2010. Physician-rated toxicity (Common Terminology Criteria for Adverse Events version 3.0) and CO were prospectively assessed during yearly follow-up, up to 5 years after radiotherapy. Multivariate logistic regression analyses using a bootstrapping method were performed.

RESULTS

At 3 years, toxicity scores of 436 patients were available. Grade ≥ 2 fibrosis in the boost area was observed in 8.5%, non-boost fibrosis in 49.4%, pain to the chest wall in 6.7%, and fair/poor CO in 39.7% of cases. Radiotherapy before chemotherapy was significantly associated with grade ≥ 2 boost fibrosis at 3 years (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.3-6.0). Non-boost fibrosis was associated with re-resection (OR 2.2, 95% CI 1.2-4.0) and larger tumors (OR 1.1, 95% CI 1.0-1.1). At 1 year, chest wall pain was significantly associated with high boost dosage (OR 2.1, 95% CI 1.2-3.7) and younger age (OR 0.4, 95% CI 0.2-0.7). A fair/poor CO was observed more often after re-resection (OR 4.5, 95% CI 2.4-8.5), after regional radiotherapy (OR 2.9, 95% CI 1.2-7.1), and in larger tumors (OR 1.1, 95% CI 1.0-1.1).

CONCLUSIONS

Toxicity and CO are not impaired after 3D-CRT-SIB. Fibrosis was not significantly associated with radiotherapy parameters. Independent risk factors for fibrosis were chemotherapy after radiotherapy, re-resection, and larger tumor size. Re-resection was most predictive for worse CO. Age had an impact on chest wall pain occurrence.

The association between breast cancer prognostic indicators and serum 25-OH vitamin D levels

BACKGROUND

Studies show that women with low vitamin D levels have an increased risk of breast cancer (BC) incidence and mortality, but there is a lack of research examining vitamin D levels and prognostic variables in BC patients. The aim of this study is to examine 25-OH vitamin D levels between BC cases and controls and by prognostic indicators among BC cases.

METHODS

25-OH vitamin D levels were collected from 194 women who underwent BC surgery and 194 cancer-free (CF) controls at the University of Rochester between January 2009 and October 2010. Mean 25-OH vitamin D levels and odds ratios (OR) were calculated by case/control status for the overall cohort and by prognostic indicators (invasiveness, ER status, triple-negative status, Oncotype DX score, molecular phenotype) for BC cases.

RESULTS

BC cases had significantly lower 25-OH vitamin D levels than CF controls (BC: 32.7 ng/mL vs. CF: 37.4 ng/mL; P = .02). In case-series analyses, women with suboptimal 25-OH vitamin D concentrations (<32 ng/mL) had significantly higher odds of having ER- (OR = 2.59, 95% confidence interval [95% CI] = 1.08-6.23) and triple-negative cancer (OR = 3.15, 95% CI = 1.05-9.49) than those with optimal 25-OH D concentrations. Women with basal-like phenotype had lower 25-OH vitamin D levels than women luminal A phenotype (basal-like: 24.2 ng/mL vs. luminal A: 32.8 ng/mL; P = 0.04).

CONCLUSIONS

BC patients with a more aggressive molecular phenotype (basal-like) and worse prognostic indicators (ER- and triple-negative) had lower mean 25-OH vitamin D levels. Further research is needed to elucidate the biological relationship between vitamin D and BC progression.

Osteoporosis related to disease or therapy in patients with cancer

Osteoporosis is a major public health issue in the general population, particularly in postmenopausal women. Patients with cancer may not only be at risk for primary osteoporosis, but for secondary osteoporosis related to cancer therapies-particularly therapies that impair gonadal function, lead to loss of serum estrogen, and negatively affect bone turnover. Normal bone remodeling is influenced by the receptor activator for nuclear kappa-B ligand pathway, calcium, vitamin D, and other nutrition factors, as well as modifiable and nonmodifiable factors. Identifying which patients with cancer are at risk for bone mineral density loss is important and may include patients with breast or prostate cancer, some survivors of pediatric malignancies, and adults with other tumors. Nurses play a major role in identifying those patients and their risk for low-impact fractures, which can have a significant effect on patient morbidity and mortality. Counseling and teaching are central nursing functions, as well as safely administering therapies, particularly bisphosphonates and denosumab.

Treatment for chemotherapy-induced alopecia in mice using parathyroid hormone agonists and antagonists linked to a collagen binding domain

Parathyroid hormone (PTH) agonists and antagonists have been shown to improve hair growth after chemotherapy; however, rapid clearance and systemic side-effects complicate their usage. To facilitate delivery and retention to skin, we fused PTH agonists and antagonists to the collagen binding domain (CBD) of Clostridium histolyticum collagenase. in-vitro studies showed that the agonist fusion protein, PTH-CBD, bound collagen and activated the PTH/parathyroid hormone-related peptide receptor in SaOS-2 cells. The antagonist fusion proteins, PTH(7-33)-CBD and PTH([-1]-33)-CBD, also bound collagen and antagonized PTH(1-34) effect in SaOS-2 cells; however, PTH(7-33)-CBD had lower intrinsic activity. Distribution studies confirmed uptake of PTH-CBD to the skin at 1 and 12 hr after subcutaneous injection. We assessed in vivo efficacy of PTH-CBD and PTH(7-33)-CBD in C57BL/6J mice. Animals were depilated to synchronize the hair follicles; treated on Day 7 with agonist, antagonist, or vehicle; treated on Day 9 with cyclophosphamide (150 mg/kg i.p.) or vehicle; and sacrificed on Day 39. Normal mice (no chemo and no treatment) showed rapid regrowth of hair and normal histology. Chemo+Vehicle mice showed reduced hair regrowth and decreased pigmentation; histology revealed reduced number and dystrophic anagen/catagen follicles. Chemo+Antagonist mice were grossly and histologically indistinguishable from Chemo+Vehicle mice. Chemo+Agonist mice showed more rapid regrowth and repigmentation of hair; histologically, there was a normal number of hair follicles, most of which were in the anagen phase. Overall, the agonist PTH-CBD had prominent effects in reducing chemotherapy-induced damage of hair follicles and may show promise as a therapy for chemotherapy-induced alopecia.

Prevention of chemotherapy-induced osteoporosis by cyclophosphamide with a long-acting form of parathyroid hormone

BACKGROUND

Most chemotherapeutics reduce bone mineral density (BMD) and increase risk for fractures by causing gonadal suppression, which in turn increases bone removal. Cyclophosphamide (CYP) also has a direct effect of inhibiting bone formation and removal, making the resulting bone loss particularly difficult to treat with antiresorptive therapy.

AIM

We tested whether a single dose of the anabolic agent PTH linked to a collagen binding domain (PTHCBD) could prevent the effects of CYP-induced bone loss.

METHODS

Mice received either buffer alone, CYP, or CYP+ PTH-CBD. BMD and alkaline phosphatase were measured every 2 weeks for a total of 8 weeks.

RESULTS

After 6 weeks, mice treated with CYP showed expected reductions in BMD (increase from baseline: 7.4 ± 6.9 vs 24.35 ± 4.86% in mice without chemotherapy, p<0.05) and decrease in alkaline phosphatase levels (42.78 ± 6.06 vs 60.62 ± 6.23 IU/l in mice without chemotherapy, p<0.05), consistent with osteoporosis from impaired bone formation. Administration of a single dose of PTH-CBD (320 μg/kg ip) prior to CYP treatment improved BMD (change from baseline: 23.4 ± 5.4 vs 7.4 ± 6.9%, CYP treatment alone, p<0.05) and increased alkaline phosphatase levels (50.14 ± 4.86 vs 42.78 ± 6.06 IU/l in CYP treatment alone, p<0.05). BMD values and alkaline phosphatase levels were restored to those seen in mice not receiving chemotherapy.

CONCLUSIONS

A single dose of PTHCBD prior to chemotherapy reversed CYP-induced suppression of bone formation and prevented CYP-induced bone loss in mice.

Zoledronic acid for adjuvant use in patients with breast cancer

Zoledronic acid, a nitrogen-containing bisphosphonate, is firmly established in the management of metastatic bone disease. It inhibits farnesyl diphosphonate synthase within the mevalonate pathway and, through this mechanism, is a potent inhibitor of osteoclast-mediated bone resorption. In addition, there are preclinical data suggesting that farnesyl diphosphonate synthase inhibition by zoledronic acid has anti-tumor effects in breast cancer. Adjuvant therapies for early breast cancer are associated with substantial decreases in bone mineral density. Results from three clinical trials, ABCSG-12, Z-FAST and ZO-FAST, indicate that the addition of twice-yearly zoledronic acid to standard adjuvant endocrine therapy in premenopausal and postmenopausal patients with hormone receptor-positive breast cancer prevents cancer treatment-induced bone loss. Moreover, it is becoming evident that it may also exert anticancer effects in an estrogen-deprived state in the adjuvant and neoadjuvant setting. However, long-term side effects need to be taken into consideration for treatment decisions.

Cancer to bone: a fatal attraction

When cancer metastasizes to bone, considerable pain and deregulated bone remodelling occurs, greatly diminishing the possibility of cure. Metastasizing tumour cells mobilize and sculpt the bone microenvironment to enhance tumour growth and to promote bone invasion. Understanding the crucial components of the bone microenvironment that influence tumour localization, along with the tumour-derived factors that modulate cellular and protein matrix components of bone to favour tumour expansion and invasion, is central to the pathophysiology of bone metastases. Basic findings of tumour-bone interactions have uncovered numerous therapeutic opportunities that focus on the bone microenvironment to prevent and treat bone metastases.

Cancer to bone: a fatal attraction

When cancer metastasizes to bone, considerable pain and deregulated bone remodelling occurs, greatly diminishing the possibility of cure. Metastasizing tumour cells mobilize and sculpt the bone microenvironment to enhance tumour growth and to promote bone invasion. Understanding the crucial components of the bone microenvironment that influence tumour localization, along with the tumour-derived factors that modulate cellular and protein matrix components of bone to favour tumour expansion and invasion, is central to the pathophysiology of bone metastases. Basic findings of tumour-bone interactions have uncovered numerous therapeutic opportunities that focus on the bone microenvironment to prevent and treat bone metastases.

The effect of various vitamin D supplementation regimens in breast cancer patients

Vitamin D deficiency in the patients treated for breast cancer is associated with numerous adverse effects (bone loss, arthralgia, and falls). The first aim of this study was to assess vitamin D status, determined by 25-OH vitamin D levels, among women diagnosed with breast cancer according to demographic/clinical variables and bone mineral density (BMD). The second aim of this study was to evaluate the effect of daily low-dose and weekly high-dose vitamin D supplementation on 25-OH vitamin D levels. This retrospective study included 224 women diagnosed with stage 0-III breast cancer who received treatment at the James P. Wilmot Cancer Center at the University of Rochester Medical Center. Total 25-OH vitamin D levels (D(2) + D(3)) were determined at baseline for all participants. Vitamin D deficiency was defined as a 25-OH vitamin D level < 20 ng/ml, insufficiency as 20-31 ng/ml, and sufficiency as ≥32 ng/ml. BMD was assessed during the period between 3 months before and 6 months following the baseline vitamin D assessment. Based on the participants' baseline levels, they received either no supplementation, low-dose supplementation (1,000 IU/day), or high-dose supplementation (≥50,000 IU/week), and 25-OH vitamin D was reassessed in the following 8-16 weeks. Approximately 66.5% had deficient/insufficient vitamin D levels at baseline. Deficiency/insufficiency was more common among non-Caucasians, women with later-stage disease, and those who had previously received radiation therapy (P < 0.05). Breast cancer patients with deficient/insufficient 25-OH vitamin D levels had significantly lower lumbar BMD (P = 0.03). Compared to the no-supplementation group, weekly high-dose supplementation significantly increased 25-OH vitamin D levels, while daily low-dose supplementation did not significantly increase levels. Vitamin D deficiency and insufficiency were common among women with breast cancer and associated with reduced BMD in the spine. Clinicians should carefully consider vitamin D supplementation regimens when treating vitamin D deficiency/insufficiency in breast cancer patients.

Zoledronic acid preserves bone mineral density in premenopausal women who develop ovarian failure due to adjuvant chemotherapy: final results from CALGB trial 79809

BACKGROUND

Chemotherapy-induced ovarian failure (CIOF) is a frequent side-effect of adjuvant chemotherapy that results in rapid bone loss. We hypothesised that zoledronic acid (ZA), a third-generation amino bisphosphonate, would prevent bone loss in premenopausal women who developed CIOF.

METHODS

Women (439) were randomised to intravenous (i.v.) ZA 4 mg every 3 months for 2 years starting within 1-3 months after randomization (arm A) or 1 year after randomization (arm B, controls). CIOF was prospectively defined as ≥ 3 months of amenorrhoea, follicle-stimulating hormone (FSH) ≥ 30 MIU/ml and non-pregnant at 1 year. The primary end-point was the percentage change in bone mineral density (BMD) in the lumbar spine (LS) from baseline to 12 months in the ZA and in control groups in women who developed CIOF; the secondary end-point was BMD in LS at 3 years in all randomised women.

FINDINGS

One hundred and fifty (56%) met the definition of CIOF at 1 year. Overall, grade 3 toxicities of ZA were fatigue (1%) arthralgias (21%) and pain (84%). The median percent change (interquartile range, IQR) at 1 year was +1.2% (-0.5% to +2.8%) and -6.7% (-9.7% to -2.9%) p<0.001 and at 3 years was +1.0% (-1.6% to +5.2%) and -0.5% (-3.7% to +3.2%) p=0.019 in arms A and B, respectively.

INTERPRETATION

ZA every 3 months is well tolerated and prevents rapid bone loss in premenopausal women that develop CIOF. Giving ZA with rather than 1 year after the start of adjuvant chemotherapy is the preferred sequence to prevent bone loss.

Integrins and bone metastasis: integrating tumor cell and stromal cell interactions

Integrins on both tumor cells and the supporting host stromal cells in bone (osteoclasts, new blood vessels, inflammatory cells, platelets and bone marrow stromal cells) play key roles in enhancing bone metastasis. Tumor cells localize to specific tissues through integrin-mediated contacts with extracellular matrix and stromal cells. Integrin expression and signaling are perturbed in cancer cells, allowing them to "escape" from cell-cell and cell-matrix tethers, invade, migrate and colonize within new tissues and matrices. Integrin signaling through αvβ3 and VLA-4 on tumor cells can promote tumor metastasis to and proliferation in the bone microenvironment. Osteoclast (OC) mediated bone resorption is a critical component of bone metastasis and can promote tumor growth in bone and αvβ3 integrins are critical to OC function and development. Tumors in the bone microenvironment can recruit new blood vessel formation, platelets, pro-tumor immune cells and bone marrow stromal cells that promote tumor growth and invasion in bone. Integrins and their ligands play critical roles in platelet aggregation (αvβ3 and αIIbβ3), hematopoietic cell mobilization (VLA-4 and osteopontin), neoangiogenesis (αvβ3, αvβ5, α6β4, and β1 integrin) and stromal function (osteopontin and VLA-4). Integrins are involved in the pathogenesis of bone metastasis at many levels and further study to define integrin dysregulation by cancer will yield new therapeutic targets for the prevention and treatment of bone metastasis.

Interventions to Alleviate Symptoms Related to Breast Cancer Treatments and Areas of Needed Research

Treatments for breast cancer produce a host of side effects, which can become debilitating. Some cancer treatment-related side effects occur in up to 90% of patients during treatment and can persist for months or years after treatment has ended. As the number of breast cancer survivors steadily increases, the need for cancer control intervention research to alleviate side effects also grows. This review provides a general overview of recent clinical research studies of selected topics in the areas of symptom management for breast cancer with a focus on cognitive difficulties, fatigue, cardiotoxicity, bone loss, insomnia, and cancer pain. We review both pharmacological and behavioral intervention clinical research studies, conducted with breast cancer patients and survivors. Additionally, clinical perspectives on symptom management and recommendations for areas of needed research are provided.

Emerging drugs for the management of cancer treatment induced bone loss

AREAS COVERED IN THIS REVIEW

We focus our attention on data on the efficacy of currently available and emerging drugs for the management of cancer treatment induced bone loss (CTIBL) found in a PubMed research from 1997 till today.

IMPORTANCE OF THE FIELD

One of the most common and severe safety issues of the antihormonal therapy in both sexes is the CTIBL and the related fragility fractures. In postmenopausal women with estrogenic receptor positive breast cancer, the third-generation aromatase inhibitors (AIs) are the standard therapy. Observational retrospective studies have found that AIs treated patients had a high rate of bone loss and fracture risk (RR 1.3). Also in men with prostate cancer receiving androgen deprivation therapy, the increase in bone turnover and the consequent bone loss are very rapid and sustained significantly increasing the fracture risk.

WHAT THE READER WILL GAIN

The aim of our review is to provide the current evidences for the management of bone loss and fracture risk in this subpopulation.

TAKE HOME MESSAGE

The very high rate of bone loss and the high incidence of fractures indicate that cancer patients at risk of CTIBL need to be carefully monitored and stratified for fracture risk. Although there is a strong evidence of efficacy in prevention of bone loss and reduction of fracture risk for many drugs approved for postmenopausal osteoporosis (PMO) and male osteoporosis, for CTIBL there are actually no drugs approved for this indication.

Effects of a structured weight-bearing exercise program on bone metabolism among breast cancer survivors: a feasibility trial

PURPOSE

Treatments for breast cancer, specifically hormonal therapy, accelerate bone loss (BL) among breast cancer survivors, leading to osteoporosis and an increase in fracture risk. Tai Chi Chuan (TCC) is a moderate form of weight-bearing exercise, equivalent to walking, and it has been shown to improve aerobic capacity and strength among breast cancer survivors and might also be effective in slowing bone loss in breast cancer survivors. This pilot study compared the influence of TCC with that of standard support therapy (ST; exercise control) on BL biomarkers among breast cancer survivors.

PATIENTS AND METHODS

Randomly assigned breast cancer survivors (N = 16; median age, 53 years; < 30 months after treatment) completed 12 weeks (3 times per week, 60 minutes per session) of TCC or ST. Serum levels of N-telopeptides of type I collagen (NTx), a marker of bone resorption, and bone-specific alkaline phosphatase (BSAP), a marker of bone formation, were determined according to enzyme-linked immunosorbent assay at baseline and after the intervention.

RESULTS

Using analysis of covariance, survivors in the TCC group experienced a greater increase in levels of bone formation (BSAP [microg/L]: before, 8.3; after, 10.2; change, 1.9 microg/L and 22.4%), compared with survivors in ST (BSAP [microg/L]: before, 7.6; after, 8.1; change, 0.5 microg/L [6.3%]). Survivors in the TCC group also experienced a significant decrease in bone resorption (NTx [nanomoles bone collagen equivalent; nmBCE]: before, 17.6; after, 11.1; change, -6.5 nmBCE; -36.9%), whereas women in the ST group did not (NTx [nmBCE]: before, 20.8; after, 18.8; change, -2.0 nmBCE; -9.6%).

CONCLUSION

This pilot study suggests that weight-bearing exercise exerts positive effects on BL, through increased bone formation and decreased bone resorption. Further examinations of the influence of TCC on bone health are warranted.

[The role of bisphosphonates of adjuvant therapy in breast cancer]

Breast cancer is the most common neoplasm in women. Bone is the most common site of metastatic spread from primary operable breast cancer, causing pain, fractures and hypercalcemia. This spread depends on the release of osteolytic substances by the cancer cells. The osteoclasts also release growth factors that can act back on the cancer cells to activate growth. Biphosphonates, antiosteolytic agents, have been shown to reduce the progression of established bone metastases. Emerging evidence suggests that biphosphonates also have antitumor and antimetastatic properties, including the inhibition of angiogenesis, tumor-cell invasion, and adhesion in bone; the induction of apoptosis; antitumor sinergy with cytotoxic chemotherapy; and immunomodulatory effects through induction of γ/δ T cells. These findings were the background and rationale for ongoing clinical trials, in order to establish their role as a part of adjuvant treatment for early breast cancer. The oral biphosphonate clodronate (1600mg/d) is effective in patients with bone metastases. When used as adjuvant therapy, given to patients with operable breast cancer for two years, clodronate has been reported to reduce the risk of bone metastases during a 2-year study period with a significant reduction in mortality. This benefit supports its use as additional adjuvant therapy for patients with operable breast cancer. Zoledronic acid, a potent nitrogen-containing biphosphonate, has been shown to maintain or increase bone mineral density (BMD) in premenopausal women with early-stage breast cancer receiving adjuvant hormone therapies as well as healthy postmenopausal women with low BMD. Recent large clinical trials with biphosphonates in the (neo)adjuvant setting for early-breast cancer, demonstrate an improvement of disease-free and overall survival as well as increased pathologic rate responses.