Department of Gastrointestinal Pathology, Instituto Nacional de Cancerología, México City, México.
Colorectal Dis. 2012 Sep;14(9):e567-72. doi: 10.1111/j.1463-1318.2012.03013.x.
Micropapillary carcinoma (MPC) is regarded as an aggressive variant of adenocarcinoma in any location. The reported proportion of a micropapillary carcinoma component in an entire tumour ranges from 5 to 95% and only one case of pure MPC has been reported. To date, approximately 130 cases of MPC in the colorectum have been reported, but it is likely that this small number is to some extent due to under-reporting because this pattern is not well recognized by the general pathologist. All previous studies have combined colonic and rectal primary tumours and most have only analysed patients with clinical Stages I or II.
We analysed 15 cases of MPC of the colon alone, diagnosed in our institution, and compared them with 105 conventional carcinomas of the colon.
An MPC component was present in 10% of all colonic carcinomas. These tumours presented at a median age of 56 years, and all were of American Joint Committee on Cancer Stages III and IV. Subserosal tissue invasion was present in every case, 60% had more than four positive lymph nodes, 60% were accompanied by poorly differentiated conventional carcinoma, 40% had had an incomplete resection and a third demonstrated lymphovascular invasion. Despite these adverse prognostic factors, tumours containing MPC showed the same survival, stage by stage, as conventional adenocarcinoma in multivariate analysis, although 3-year survival (81.7%vs 87.3%, P=0.035) was worse on univariate analysis.
The histopathologist should be aware of the possibility of MPC. Three-year survival is worse than in patients with conventional colonic carcinomas in Stage III.
微乳头癌（MPC）被认为是任何部位腺癌的侵袭性变体。在整个肿瘤中，微乳头癌成分的报告比例为 5%至 95%，仅报告过一例纯 MPC。迄今为止，大约有 130 例结直肠 MPC 被报道，但由于这种模式未被普通病理学家很好地识别，因此报告的数量可能在一定程度上存在低估。所有以前的研究都将结肠和直肠的原发性肿瘤结合在一起进行分析，而且大多数研究仅分析了临床 I 期或 II 期的患者。
我们分析了在我们机构诊断的 15 例单独结肠 MPC 病例，并与 105 例常规结肠癌进行了比较。
MPC 成分在所有结肠腺癌中的占比为 10%。这些肿瘤的中位年龄为 56 岁，均为美国癌症联合委员会（AJCC）分期 III 期和 IV 期。所有病例均存在浆膜下组织浸润，60%的病例有超过 4 个阳性淋巴结，60%伴有低分化常规癌，40%的病例为不完全切除，三分之一的病例有淋巴血管侵犯。尽管存在这些不良预后因素，但在多因素分析中，含有 MPC 的肿瘤与常规腺癌的分期生存情况相同，尽管在单因素分析中 3 年生存率（81.7%对 87.3%，P=0.035）较差。
病理学家应该意识到 MPC 的可能性。3 年生存率比 III 期常规结肠癌患者差。
