Breast Cancer with Bone Metastasis: Molecular Insights and Clinical Management

Despite the remarkable advances in the diagnosis and treatment of breast cancer patients, the presence or development of metastasis remains an incurable condition. Bone is one of the most frequent sites of distant dissemination and negatively impacts on patient's survival and overall frailty. The interplay between tumor cells and the bone microenvironment induces bone destruction and tumor progression. To date, the clinical management of bone metastatic breast cancer encompasses anti-tumor systemic therapies along with bone-targeting agents, aimed at slowing bone resorption to reduce the risk of skeletal-related events. However, their effect on patients' survival remains controversial. Unraveling the biology that governs the interplay between breast neoplastic cells and bone tissue would provide means for the development of new therapeutic agents. This article outlines the state-of-the art in the characterization and targeting the bone metastasis in breast cancer, focusing on the major clinical and translational studies on this clinically relevant topic.

Advances in Multiple Myeloma and Spine Disease

Progressive bone destruction is the hallmark of multiple myeloma (MM) and is responsible for principal morbidity in the disease. The spine is the most afflicted skeletal organ, and vertebral fractures have significantly contributed to its poor prognosis. The principal underlying pathologic mechanism causing bone disease in MM is a shift in the balance of bone formation and bone resorption toward bone resorption, and eventually total dissociation between the 2 processes occurs in latter stages of the disease. During the past decade bisphosphonates have become an important adjunctive treatment in the management of MM, in which they have shown the ability to reduce bony complications associated with the disease. Advances in minimally invasive surgical techniques, such as percutaneous vertebroplasty and kyphoplasty, offer these patients less-invasive options for the treatment of vertebral collapse and restoration of their normal function. This report reviews recent advances in the understanding of bone disease in MM, the role of bisphosphonates in the prevention of skeletal events, and available data regarding percutaneous vertebroplasty and kyphoplasty.

Extended survival in advanced-stage multiple myeloma patients treated with gallium nitrate

Adjunctive anti-bone resorption therapy has become an important part of multiple myeloma (MM) treatment. Currently, no definite evidence exists that this therapy increases survival. We examined a cohort of 13 of 167 patients (8%) treated with the M-2 protocol who received adjuvant gallium nitrate (GN) treatment for osteolysis, and then compared the outcome of these patients to all individuals treated with the M-2 regimen. The stage at diagnosis was IA in two patients, IIIA in 10 patients and IIIB in one. Median age at diagnosis was 51 years (range 35-73). Median (range) of entry data were: paraprotein level: 6000mg/dl (3058-8675); beta2M: 2.7mg/l, (1.2-9.6); LDH: 166U/l (142-237); hemoglobin: 10.2 g/dl (8.3-12.6); albumin: 3.7 g/dl (2.5-5.0); calcium: 10.0 mg/dl (8.3-14.5); creatinine: 1.2 mg/dl (0.7-2.7). Median survival in these patients was 87+ months from time of diagnosis compared with 48 months for all other patients treated on the M-2 protocol. We identified a subgroup of patients with remarkably prolonged survival who had received M-2 chemotherapy and GN. Survival in this group markedly exceeds expectations for patients with advanced stage disease and poor prognostic features. The administration of GN may have a positive impact on survival either by decreasing skeletal complications or through a direct action of GN on the complex cytokine network involved in the proliferation of the malignant myeloma cell.