2021 Volume 12 Issue 5 Pages 729-734
Introduction: Bone metastasis (BM) is more likely to occur in lung cancer (LC) and greatly affects patients' prognosis and quality of life. LC has been treated according to a histological classification that is based on genetic mutations. The epidermal growth factor receptor (EGFR) -tyrosine kinase inhibitor (TKI) and anaplastic lymphoma kinase (ALK) -TKI significantly prolong prognosis. However, few reports have examined BM in detail in terms of histological type. Therefore, we retrospectively investigated the period, site, and treatment of BM in LC and clarified the characteristics of BM progression on the basis of the histological type of LC.
Methods: A total of 87 patients with BM due to LC with pathological diagnosis between 2013 and 2017 at our institute were included and analyzed. Clinical charts and imaging studies were also reviewed.
Results: The patients included 24 cases of EGFR/ALK mutation positive adenocarcinoma (ADP), 38 cases of mutation negative adenocarcinoma (ADN), 13 cases of squamous cell carcinoma (SCC), and 12 cases of small cell LC (SCLC). TKI was administered to 95.8% of the patients with ADP. The period until BM diagnosis was shorter in patients with SCLC but longer in those with ADP (6.0 vs. 22.8 months). The incidence of BM at the time of diagnosis was lower in patients with SCC and higher in those with ADP and SCLC (BM score: 3.0 vs. 6.6 vs. 6.9, respectively; p < 0.05). BM score for patients with ADP was higher than that for patients with ADN (6.6 vs. 4.3; p = 0.053). The survival period after the first diagnosis of BM was shorter in patients with SCC but longer in those with ADP (3.6 vs. 13.2 month).
Conclusions: Patients with SCLC showed multiple BM in a relatively short time from LC diagnosis. Patients with ADP had a relatively long time until BM diagnosis and showed multiple lesions at that time. And the prognosis of life after BM diagnosis was relatively long. Histological prognosis of LC could be an indicator for orthopedic therapeutic interventions.
