Skeletal metastases in non-small cell lung cancer: a retrospective study

The skeleton is one of the most common sites of metastasis in patients with advanced cancer. Bone metastases often cause SREs (skeletal-related events). Despite advances in the treatment of primary lung cancer, SREs still affect many patients. Therefore, we planned a retrospective study to investigate the clinical impact of SREs, and to compare differences in the therapeutic outcome between patients with and without skeletal metastases or SRE.

We retrospectively investigated the charts of all 259 patients with non-small cell lung cancer (NSCLC) who consulted the Department of Medical Oncology at Kinki University School of Medicine between February 2002 and January 2005. We assessed their TNM stage, presence of skeletal metastases (on bone scintigraphy, MRI, and plain X-ray films), and outcome parameters such as SREs, analgesic use, and survival.

A total of 70 patients (30.4%) were found to have skeletal metastases during their clinical course and 35 patients (50%) out of all 70 patients had SREs. Among 135 stage IV patients, a total of 56 (41%) had skeletal metastases, and 25 of these 56 patients (45%) had SREs. The most common SREs were the need for radiotherapy (34.3%) and hypercalcemia (20%). Patients with SREs tended to have worse survival, while no significant difference of survival was observed between patients with and without skeletal metastases.

It seems to be important to prevent SREs during the treatment of NSCLC, so further studies evaluating bisphosphonates in combination with chemotherapy are warranted.