Pleural metastases as a unique entity with dismal outcome of head and neck squamous cell carcinoma

Abstract

Once distant metastasis occurs, head and neck squamous cell carcinoma (HNSCC) patients generally have a poor prognosis with limited treatment options. A subgroup of patients who developed pleural metastases after curative treatment of localized HNSCC appeared to have worse outcomes. All patients from National Taiwan University Hospital who were diagnosed with localized HNSCC from January 1, 2000 to December 31, 2007 and developed distant metastases were included in this analysis. Medical records were reviewed. Patients with pleura as the first metastatic sites were compared to those with other first metastases for differences in basic demographics, time to distant metastasis (TTM) and overall survival (OS). A total of 198 patients were included, and 52 (26%) had pleural involvement at first diagnosis of distant metastases. Younger age at diagnosis (P=0.002) and buccal mucosa origin (P=0.006) were risk factors for developing pleural metastases. Patients with pleura as the first metastatic sites, compared to those with other first metastases, had significantly shorter TTM (median 7.5 vs. 11.1 months, P<0.001) and OS (median 9.6 vs. 16.5 months, P<0.001). By multivariate analysis, pleural metastases remained an independent predictor for shorter OS. In conclusion, patients with pleural metastases comprise a unique subgroup of HNSCC which rapidly develop distant metastases with poor prognosis.