对１５例无肿块型乳腺癌进行临床及病理分析。这种乳腺癌术前绝大多数被诊断为乳腺增生。其临床特点表现为患者年轻；乳腺触诊无明确肿块，仅表现为区段乳腺增厚；个别病例有乳头溢液，乳腺Ｘ线片可发现腺体内有散在泥沙样钙化，但无肿块影；针吸细胞学检查阳性率低；冰冻切片检查有时也难以作出判断。病理特点主要是癌灶为多灶性的浸润性导管癌；癌灶小，分布广，但只局限在乳腺某一区段内；病变区的腺体都有增生背景。这种类型乳腺癌如能及时发现，预后较好。 Fifteen cases of non-tumor breast cancer were analyzed clinically and pathologically. The vast majority of preoperative breast cancers were diagnosed with hyperplasia of the breast. The clinical features of the patient were young; there was no clear mass in the palpation of the breast, and only the segment showed thickening of the breast; individual cases had nipple discharge, mammography showed scattered sand-like calcification in the gland, but no mass Shadow; positive rate of needle-aspiration cytology is low; frozen section examination is sometimes difficult to judge. The main pathological features are multifocal invasive ductal carcinomas; the lesions are small and widely distributed, but only in a certain segment of the breast; the glands in the affected area have a hyperplastic background. If this type of breast cancer can be found in time, the prognosis is better.