The surface of tumor cells and tumor cells have the inner surface of the thin hair-like microvilli Peng, cytoplasmic actin-rich tension and glycogen granules, or double-layer membrane of intermittent, the tumor cells have more of the bridge DMM tablets for the ultrastructural characteristics of the Key〕 3. Microvilli and, in the middle and the wire inside the cytoplasm of the new triad cavity known as mesothelioma. Adenocarcinoma and microvilli short and thick, with secretory granules in cytoplasm, outside the gland cells form a cavity for the characteristics of the cancer. Key in the country, such as 4〕 dMM study found that the average value of microvilli aspect ratio> 11, metastatic lung cancer and pleura plush aspect ratio average value of <5, put the average value of the microvilli aspect ratio can be used as identification of cancer and dMM An indicator. DMM and pleural pleural metastatic adenocarcinoma of the bridge between the average grain length of the obvious differences, but the number of different pleura dMM desmosome longer than 1.5μ m, and pleural metastatic lung cancer 1 case of no longer than desmosome 1.5μ m. As a result, applications ultrastructure measurement of the length of the bridge tablets dMM diagnosed with pleural pleural metastatic adenocarcinoma of the differential diagnosis must also value.