Preliminary analysis of distinct clinical and biologic features of bone metastases in melanoma

Factors associated with skeletal-related events in patients with bone metastatic melanoma: A retrospective study of 481 patients

OBJECTIVES

Metastatic bone disease is estimated to develop in up to 17% of patients with melanoma, compromising skeleton integrity resulting in skeletal-related events (SREs), which impair quality of life and reduce survival. The objective of the study was to investigate (1) the proportion of melanoma patients developing SREs following diagnosis of bone metastasis and (2) the predictors for SREs in this patient cohort.

METHODS

Four hundred and eighty-one patients with bone metastatic melanoma from two tertiary centers in the United States from 2008 to 2018 were included. The primary outcome was 90-day and 1-year occurrence of a SRE, including pathological fractures of bones, cord compression, hypercalcemia, radiotherapy, and surgery. Fine-Gray regression analysis was performed for overall SREs and pathological fracture, with death as a competing risk.

RESULTS

By 1-year, 52% (258/481) of patients experienced SREs, and 28% (137/481) had a pathological fracture. At 90-day, lytic lesions, bone pain, elevated calcium and absolute lymphocyte, and decreased albumin and hemoglobin were associated with higher SRE risk. The same factors, except for decreased hemoglobin, were shown to predict development of SREs at 1-year.

CONCLUSION

The high incidence of SREs and pathological fractures warrants vigilance using the identified factors in this study and preventative measures during clinical oncological care.

Incidence, Risk Factors, and Survival of Bone Metastases and Skeletal-Related Events in Melanoma Patients: A Systematic Review and Quality Assessment of 29 Studies

Background

Skeletal metastases make up 17% of all metastases from advanced-stage melanoma. Bone metastases are associated with increased morbidity and mortality and decreased quality of life due to their association with skeletal-related events (SREs), including pathological fracture, spinal cord compression, hypercalcemia, radiotherapy, and surgery. The study aimed to determine the incidence of bone metastases and SREs in melanoma, identify possible risk factors for the development of bone metastases and SREs, and investigate survival rates in this patient population.

Methods

A computer-based literature search was conducted using Pubmed, Embase, and Cochrane Central Register of Controlled Trials up to July 2023. The Newcastle-Ottawa Quality Assessment Scale (NOS) was utilized for quality assessment. Study characteristics, patient information, risk factors for developing bone metastases and SREs, and characteristics for survival were recorded.

Results

We included 29 studies. The average bone metastasis-free interval ranged from four to 72 months. Incidence of bone metastases varied from 2 % to 49 % across 14 studies. 69 % (20/29) of studies described the location of bone metastases, with 24 % (7/29) focusing solely on spinal metastases. In one study, 129 SREs were recorded in 71 % (59/83) of the patient cohort, with various manifestations. The use of bone-directed agents was independently associated with lower risk of SREs. Survival after detection of bone metastasis ranged from three to 13 months. Factors associated with survival included clinical, tumor-related, and treatment features.

Conclusion

This review highlights the notable prevalence and risk factors of developing bone metastases and subsequent SREs in patients with melanoma. The surge in bone metastases poses a challenge in complication management, given the high prevalence of SREs. While this study offers a comprehensive overview of the incidence, risk factors, and outcomes associated with bone metastases and SREs in melanoma patients that may guide patient and physician decision-making, a notable gap lies in the limited availability of high-quality data and the heterogeneous design of the existing literature. Future research should address predictive factors for bone metastases and SREs in melanoma to facilitate patient and physician decision-making and ultimately improve outcomes in this patient population.

Management of metastatic bone disease of melanoma

One of the most aggressive tumors arising from the skin, mucosa, and uvea is malignant melanoma, which easily metastasizes. Bone tissue is one of the most typical locations for distant metastasis, and around 5%-20% of patients eventually acquired skeletal metastases. For decades, the incidence of bone metastases was higher, bringing greater burden on the family, society, and healthcare system owing to the progress of targeted therapy and immunotherapy, which prolonging the survival time substantially. Moreover, bone metastases result in skeletal-related events, which influence the quality of life, obviously. Appropriate intervention is therefore crucial. To obtain the optimum cost-effectiveness, existing treatment algorithm must be integrated, which is still controversial. We have aimed to throw light on current views concerning the formation, biological and clinical features, and treatment protocol of melanoma bone metastases to guide the decision-making process.

Extracellular Vesicles in Tumors: A Potential Mediator of Bone Metastasis

As one of the most common metastatic sites, bone has a unique microenvironment for the growth and prosperity of metastatic tumor cells. Bone metastasis is a common complication for tumor patients and accounts for 15-20% of systemic metastasis, which is only secondary to lung and liver metastasis. Cancers prone to bone metastasis include lung, breast, and prostate cancer. Extracellular vesicles (EVs) are lipid membrane vesicles released from different cell types. It is clear that EVs are associated with multiple biological phenomena and are crucial for intracellular communication by transporting intracellular substances. Recent studies have implicated EVs in the development of cancer. However, the potential roles of EVs in the pathological exchange of bone cells between tumors and the bone microenvironment remain an emerging area. This review is focused on the role of tumor-derived EVs in bone metastasis and possible regulatory mechanisms.