Clinical application of image processing and neural network in cytopathological diagnosis of lung cancer / 中华胸心血管外科杂志

Objective To study a new technique (lung cancer diagnossing system, LCDS) based on the computer imaging and artificial neural network for early diagnosis of lung cancer, and evaluate it's value in early cytopathological diagnosis of lung cancer. Methods The cytological smears from the specimens obtained by Percutaneous Aspiration Lung Biopsy (PALB) in 512 cases were synthetically analyzed by LCDS. Among them, 362 cases received operations. The diagnoses by LCDS were compared with postoperative histopathological diagnosis. Results In cytopathological diagnoses for the 512 specimens, LCDS can judge between cancer cells and non-cancer cells from lung lesions with its image analysis and expert system. Moreover, it can distinguish squamous carcinoma, adenocarcinoma and small cell carcinoma in cytopathological diagnosis with built-in neural network. The total coincident rate of LCDS diagnosis was 91.80% compared with the pathological diagnosis. In the 362 cases, the sensitivity of LCDS diagnosis was 94.79% (291/307), the specificity was 90.91%(50/55), and the consistent rate was 94.20%(341/362). Conclusion The diagnostic pattern of LCDS was practical and effective. It has applicable value in cytopathological diagnosis of lung cancer and may be an efficient means for early diagnosis of lung cancer.

Analysis on point mutation of the CDKN2/p16 gene in lung cancer / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the status of CDKN2/p16 gene point mutation in lung cancer.</p><p><b>METHODS</b>Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing were used to detect the point mutation of CDKN2/p16 gene exon 2 in 89 cases of lung cancer.</p><p><b>RESULTS</b>In 69 cases of the lung cancer without deletion of CDKN2/p16 gene exon 2, 16 cases were found to have suspicious abnormality of CDKN2/p16 gene exon 2 by PCR-SSCP, and in these 16 cases, 9 were found to harbor point mutations of CDKN2/p16 gene exon 2 by automated sequencing analysis.</p><p><b>CONCLUSION</b>The point mutation is one of the mechanisms for CDKN2/p16 gene inactivation, but it is not the chief mechanism. The inactivation of CDKN2/p16 gene aroused by point mutation plays a role to some extent in the genesis and progression of lung cancer.</p>

EXPRESSION OF THE p16 AND Rb GENES mRNA AND PROTEIN LEVELS IN LUNG CANCER / 解放军医学杂志

The authors used immunohistochemistry and in situ hybridization to observe the expression of the p16 and Rb mRNA and protein levels in 89 cases of lung cancer. The results showed that the loss of p16 gene expression took place mainly in non small cell lung cancer, and loss of Rb gene expression mainly in small cell lung cancer. The expression of these genes on protein level fundamentally corresponded with mRNA level. It is suggested that the expression of these two genes are related to the histological type of lung cancer, and the p16 and Rb genes can be considered as one of molecular biological targets for gene classification diagnosis. There may exist a mechanism at gene translation level which leads to the inactivation of the p16 and Rb genes.