Yu-Hung Fang, Chien-Chin Hsu, Meng-Jer Hsieh, Ming-Szu Hung, Ying-Huang Tsai, Yu-Ching Lin

Hypertrophic pulmonary osteoarthropathy (HPOA) is a rare disease that most commonly occurs secondary to lung cancer. However, the clinical significance of HPOA remains unclear. The aim of this study was to evaluate the impact of HPOA on patients with lung cancer in Taiwan. Data regarding lung cancer patients who demonstrated findings of HPOA on bone scintigraphy between 2010 and 2016 were retrospectively analyzed. Pathological confirmation of cases was conducted at Chiayi and Kaohsiung Chang Gang Memorial Hospital. Clinical characteristics, including gender, smoking status, histology subtype, clinical stage, and epidermal growth factor receptor (EGFR) status were investigated. We identified 69 lung cancer patients with typical HPOA findings on bone scintigraphy. Among them, 56 were male (81.2%) and 51 were ex-smokers or current smokers (73.9%). Adenocarcinoma was the most common histology subtype (n=42, 60.9%). Of 34 patients subjected to EGFR mutation analysis, only 4 (11.8%) had EGFR-tyrosine kinase inhibitor (EGFR-TKI)-sensitive mutations. Male, smoking, and adenocarcinoma were the most common clinical characteristics of lung cancer patients with HPOA in our cohort. However, the proportion of EGFR-TKI-sensitive mutation cases was extremely low.