Hypertrophic Pulmonary Osteoarthropathy as a Paraneoplastic Manifestation of Lung Cancer

IntroductionThis study examined the frequency of hypertrophic pulmonary osteoarthropathy (HPO) and the clinical characteristics of lung cancer with HPO.MethodsThe results of 2625 lung cancer patients who underwent bone scintigraphy were reviewed to identify patients with HPO, which was diagnosed when the bone scintigram showed a diffuse, symmetric pattern of bilateral increased uptake in the long tubular bones. Clinical characteristics were investigated based on the clinical and pathologic records.ResultsNineteen patients (0.72%) were found to have HPO: 17 were men, 17 were heavy smokers, and 13 had clinical stage IIIB or IV disease. Ten patients complained of pain or edema in the extremities, and seven of them had stage IIIB or IV disease. In four patients with clinical stage IIIB or IV disease, HPO was not detected at the first presentation, and the diagnosis was made after disease progression. The symptoms of HPO improved in two patients who underwent surgical resection but in only three of five patients who received chemotherapy. The HPO findings on the bone scintigram improved in 2 of 3 patients who underwent surgical resection and 5 of 11 patients who received chemotherapy.ConclusionsLess than 1% of the lung cancer patients developed HPO as a paraneoplastic manifestation. Males, heavy smokers, and advanced disease predominated in lung cancer patients with HPO. The symptoms and bone scintigram findings of HPO improved in half of the patients on treating the lung cancer.