Diagnostic and prognostic validity of serum bone turnover markers in bone metastatic non-small cell lung cancer patients

With the ageing population in most countries, disorders of bone and mineral metabolism are becoming increasingly relevant to every day clinical practice. Consequently, the interest in, and the need for effective measures to be used in the screening, diagnosis and follow-up of such pathologies has markedly grown. Together with clinical and imaging techniques, biochemical tests play an important role in the assessment and differential diagnosis of metabolic bone disease. In recent years, the isolation and characterisation of cellular and extracellular components of the skeletal matrix have resulted in the development of molecular markers that are considered to reflect either bone formation or bone resorption. These biochemical indices are non-invasive, comparatively inexpensive and, when applied and interpreted correctly, helpful tools in the diagnostic and therapeutic assessment of metabolic bone disease. Part I of this article provides an overview of the basic biochemistry of bone markers, and sources of non-specific variability. Part II (to be published in a subsequent issue of this journal) will review the current evidence regarding the clinical use of biochemical markers of bone remodelling in metabolic and metastatic bone disease.

The prognosis of patients with bone metastasis from lung cancer has not been well documented. We assessed the survival rates after bone metastasis and prognostic factors in 118 patients with bone metastases from lung cancer. The cumulative survival rates after bone metastasis from lung cancer were 59.9% at 6 months, 31.6% at 1 year, and 11.3% at 2 years. The mean survival was 9.7 months (median, 7.2 months; range, 0.1-74.5 months). A favorable prognosis was more likely in women and patients with adenocarcinoma, solitary bone metastasis, no metastases to the appendicular bone, no pathologic fractures, performance status 1 or less, use of systemic chemotherapy, and use of an epithelial growth factor receptor inhibitor. Analyses of single and multiple variables indicated better prognoses for patients with adenocarcinoma, no evidence of appendicular bone metastases, and treatment with an epithelial growth factor receptor inhibitor. The mean survival period was longer in a small group treated with an epithelial growth factor receptor inhibitor than in the larger untreated group. The data preliminarily suggest treatment with an epithelial growth factor receptor inhibitor may improve survival after bone metastasis.

The purpose of our study was to determine the incidence and locations of M1 disease at presentation in patients with non-small cell lung cancer to help design appropriate preoperative imaging algorithms. All patients with non-small cell lung cancer seen between 1991 and 1993 were identified, and records were reviewed. For patients with M1 disease, the sites of distant metastases and the methods of diagnosis were recorded. Of 348 patients identified, 276 (79%) had M0 disease and 72 (21%) had M1 disease. In 40 of 72 patients (56%), M1 disease was detected via chest or abdominal computed tomography (CT). Brain, bone, liver, and adrenal glands were the most common sites of metastatic disease, in decreasing order. Brain metastases often occurred as an isolated finding, although isolated liver metastases were uncommon. M1 disease was common at presentation, and was often detectable via chest CT. The incremental yield of abdominal CT over chest CT was very small, and therefore abdominal CT is not an effective method of screening for metastases if chest CT has been performed.