[病理学]诊断肉瘤的主要形态依据：

答复：本题选D。

                                             癌                                                                                           肉瘤

组织来源                         上皮组织                                                                                  间叶组织

发生率                        常见，80%左右                                                                       较少见，20%左右

年龄                                中年以上                                                                                青少年多见

部位                       皮肤、粘膜、内脏多见                                                                   四肢、躯干多见

大体形态            灰白色，细颗粒状，干燥，质较硬                                          粉红色，细腻，鱼肉状，质较软

组织学特点  癌细胞成卵巢状、腺管状、索状排列。实质与间质分界清楚              瘤细胞弥漫排列，与间质混杂

网状纤维                  癌细胞间无网状纤维                                                                 瘤细胞之间有网状纤维

转移方式                        淋巴道为主                                                                                  血道为主