Background: To compare the improved Saccomanno method with conventional method not only on concentrating and detecting cytological sputum but also on preserving sputum samples for further molecular biological and flow cytometry (FCM) investigation in lung cancer patients.
Methods: A total of 125 cases were identified as lung cancer by histological or cellular pathology, and sputum samples from these patients were collected by conventional method and improved Saccomannomethod respectively for sputum smear. Then, some sputum samples collected by improved Saccomanno method were studied by FCM and/ or PCR-SSCP-silver stain.
Results: The positive smear rates were 55. 2%( 69/ 125) by improved Saccomannomethod and 28%( 35/ 125) by conventionalmethod respectively ( P < 0. 01) . Of the 125 cases, 58 by improved Saccomannomethod and 26 by conventional method were confirmed for histological types of lung cancer respecitvely, and a highly significant difference was observed between the two groups ( P < 0. 01) . The positive smear rate by improved Saccomannomethod had significant correlation with the clinical characteristics such as histology, TNM stage, and type of lung cancer . Moreover, of the samples collected by improved Saccomanno method, 41 cases were selected to detect p53 point mutation by PCR-SSCP-silver stain and 30 cases were selected to quantitate p53 and p21 protein by FCM technique successfully, the positive rates were 53. 7% ( 22/ 41) , 40%( 12/ 30) and 53. 3% ( 16/ 30) respectively.
Conclusions: The results indicate that improved Saccomannomethod has a higher value than conventionalmethod not only on concentrating and detecting cytological sputum but also on preserving sputum sample for further molecular biological study.