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Clinical factors related to suspected second primary lung cancer development in patients with head and neck cancer.

PURPOSE
The rate of second primary lung cancer development for patients with head and neck cancer (HNC) has been noted. The aim of our study was to evaluate the incidence and clinical features of suspected second primary lung cancer that developed in patients with primary HNC.


MATERIALS AND METHODS
We conducted a retrospective study of 469 patients who were newly diagnosed with HNC at the Korea University Medical Center between January 2000 and December 2006.


RESULTS
A total of 469 patients were included (389 men and 80 women). Eighteen patients (3.8%) had suspected second primary lung cancers. Statistically significant clinical variables for lung cancer development included the origin site for the primary HNC (oro-hypopharynx and larynx) (p=0.048), abnormal chest x-ray findings (p=0.027) and the histological HNC type (squamous cell carcinoma) (p=0.032). When the second primary lung cancers were combined with HNCs, the adjusted overall survival of patients with a second primary lung cancer was 16 months (p<0.001).


CONCLUSIONS
Considering the relative risk factors for a second primary lung cancer developing in patients with HNC, advanced diagnostic tools, such as chest CT or PET CT scan, should be applied for the early detection of a second primary lung cancer.