乳腺乳头状癌病理亚型病例的临床及影像学特征

  目的  研究乳腺乳头状癌病理亚型病例的超声(US)、乳房X线摄影(MG)和MRI影像图谱，对比分析乳头状癌病理亚型病例的临床和影像特征差异及其临床意义。  方法  收集2012年2月~2021年12月病理确诊的47例乳腺乳头状癌患者临床和影像学检查资料。根据世界卫生组织最新肿瘤组织学分类，将纳入的47例患者(49个病灶)分为4组:乳头状导管原位癌(pDCIS)组、包裹性乳头状癌(EPC)组、实体性乳头状癌(SPC)组和浸润性乳头状癌(IPC)组。比较不同病理组的临床特征(n=47)、US(n=47)、MG(n=45)和MRI(n=14)的影像特征差异。根据BI-RADS分类标准，将BI-RADS分类≥4A认为是阳性诊断，分析3种影像学的误诊率。  结果  临床特征:所有组中触及包块比乳头溢液更多见。pDCIS(9/16，56.3%)亚组乳头溢液占比最高，IPC亚组触诊到包块的占比最高(9/11，81.8%)。US影像特征:IPC亚组的肿块形态不规则占比高于EPC亚组(P=0.023);IPC亚组的肿块边界不清占比远高于SPC组(P=0.025);与pDCIS相比，EPC亚组的囊实性肿块占比更高(P=0.048)。MG影像特征:SPC亚组肿块形态不规则的占比最高(4/6，66.7%)，EPC亚组表现为形态规则的占比最高(5/6，83.3%); 在肿块边界不清或星芒状特征方面，SPC亚组占比高于pDCIS亚组(P=0.015)。MRI影像特征:SPC组的ADC低于其他亚组(ADC=0.37×10-3 mm2/s，P=0.005)，EPC亚组低于pDCIS亚组(P=0.017)。US、MG及MRI的误诊率分别为46.8%、37.8%及14.3%，US的误诊率高于MRI(P=0.029)。  结论  乳腺乳头状癌亚组之间影像特征存在重叠。虽然US和MRI均可显示肿瘤形态学特征，但US误诊率显著高于MRI。MG对肿瘤钙化类型和分布更敏感，MRI在发现肿瘤扩散及伴发的同时性肿瘤方面更有效。US显示的肿块内血流信号、US和MG显示的肿块边缘及形态、MRI表观扩散系数等影像特征在乳腺乳头状癌病理亚型病例中存在差异。 

Clinical and imaging characteristics of papillary carcinoma of the breast

  Objective  To investigate the ultrasound (US), mammography (MG) and MRI profiles of the pathological subtypes of papillary carcinoma of the breast, to compare and analyze the differences of clinical and imaging features and clinical significance of the pathological subtypes of papillary carcinoma.  Methods  The clinical and imaging data of 47 patients with pathologically confirmed breast papillary carcinoma from February 2012 to December 2021 were collected. According to the latest tumor histological classification of World Health Organization, the patients were divided into four groups: papillary ductal carcinoma in situ (pDCIS), encapsulated papillary carcinoma (EPC), solid papillary carcinoma (SPC) and invasive papillary carcinoma (IPC) groups. The clinical features (n=47), ultrasound (n=47), MG (n=45) and MRI (n=14) of different pathological groups were compared. According to the BI-RADS classification criteria, BI-RADS classification ≥4A was considered as a positive diagnosis, and the misdiagnosis rate of the three imaging methods was analyzed.  Results  Clinical features: Palpable mass was more common than nipple discharge in all groups. pDCIS (9/16, 56.3%) had the highest proportion of nipple discharge, and IPC (9/11, 81.8%) had the highest proportion of palpation of mass. US imaging features: The proportion of irregular mass shape in IPC subgroup was also significantly higher than that in EPC subgroup (P=0.023). The proportion of unclear mass boundary in IPC subgroup was much higher than that in SPC group (P=0.025). Compared with pDCIS, EPC subgroup had a higher proportion of cystic solid mass (P=0.048). MG imaging features: The SPC subgroup had the highest proportion of irregular mass shape (4/6, 66.7%), and the EPC subgroup had the highest proportion of regular mass shape (5/6, 83.3%). The proportion of the SPC subgroup was higher than that of the pDCIS subgroup (P=0.015). MRI imaging features: The ADC of SPC group was lower than that of other subgroups (ADC=0.37×10-3 mm2/s, P=0.005), and EPC group was lower than pDCIS subgroup (P=0.017). The misdiagnosis rates of US, MG and MRI were 46.8%, 37.8% and 14.3%, respectively, and the misdiagnosis rate of US was significantly higher than that of MRI (P=0.029).  Conclusion  The imaging features of papillary breast carcinoma subgroups overlap. Although both US and MRI can show the morphological characteristics of tumors, the misdiagnosis rate of US is significantly higher than that of MRI. MG is more sensitive to the type and distribution of tumor calcification, and MRI is more effective in detecting tumor spread and concurrent tumors. The blood flow signal in the mass shown by US, the margin and morphology of the mass shown by US and MG, and the apparent diffusion coefficient of MRI are different in the histological subtypes of breast papillary carcinoma.