Differential expression of hypoxia-inducible factor 1α in non-small cell lung cancer and small cell lung cancer

OBJECTIVES: The aim of this study was to compare the expression of hypoxia-inducible factor 1α and vascular endothelial growth factor in small cell lung cancer and subtypes of non-small cell lung cancer and examine their relationships with clinicopathologic factors, response to treatment and survival. METHODS: We examined samples obtained by bronchial endoscopic biopsy from 55 patients with inoperable lung cancer (16 with adenocarcinoma, 17 with squamous cell carcinoma, and 22 with small cell lung cancer). Hypoxiainducible factor 1α and vascular endothelial growth factor were detected using immunohistochemistry. The diagnosis, treatment, and follow-up of patients were conducted according to the standard practice. RESULTS: A significant difference (p=0.022) in hypoxia-inducible factor 1α expression was observed between nonsmall cell lung cancer (75.8% positive) and small cell lung cancer (45.5% positive). The frequency of hypoxiainducible factor 1α nuclear expression was 88.2% in squamous cell carcinoma, 62.5% in adenocarcinoma, and 45.5% in small cell lung cancer. A significant correlation was observed between hypoxia-inducible factor 1α and vascular endothelial growth factor expression (Fisher's exact test, p=0.001) when all types of lung cancer were examined, either collectively or separately. CONCLUSIONS: The expression of hypoxia-inducible factor-1α differs significantly between subtypes of lung cancer. These findings could help elucidate the biology of the different types of non-operable lung carcinomas and have implications for the design of new therapeutic approaches for lung cancer.

Primary Small Cell Carcinoma of the Lung Presenting with Breast and Skin Metastases

Cutaneous metastases originating from an internal cancer are relatively uncommon in clinical practice, and metastatic lesions to the breast are rarer than those to the skin. Skin metastases of lung cancer, which may be the first sign of the disease, usually indicate progressive disease and a poor prognosis. We describe a 47-year-old male who presented with recurring masses in the lumbar region bilaterally and the right breast. Immunohistochemical findings and radiological imaging suggested lung cancer. This is the first reported case of small cell lung cancer metastasizing to two separate, uncommon sites, the skin and breast.