Abstract:
Lymph nodes with acellular mucin harvested from treated colorectal cancers (CRC) are staged as pN0. However, there is variability among pathologists while reporting the pN stage when acellular mucin is found within nodes of untreated CRCs. While the UICC guidelines suggest staging them as pN1, the AJCC and CAP do not offer any recommendations. In order to characterize their clinicopathologic features and outcome, we compared 16 untreated CRCs (study group; mean age: 68 years) harboring nodes with acellular mucin with 34 pN0 and 25 pN1 untreated CRC controls. All tumors were unifocal; 12 (75%) were right-sided lesions. Most cases (75%) showed one node with acellular mucin (range: 1-3). MMR-deficient tumors were significantly more common in the study group (83%) compared to pN0 (33%; p = 0.006) and pN1 controls (8%; p < 0.001). The overall survival of study group patients was closer to pN0 compared to pN1 controls; however, this difference was not statistically significant. In conclusion, untreated CRC that harbor acellular mucin within lymph nodes commonly present as right-sided, MMR-deficient tumors in older women that show a non-mucinous phenotype. While the limited number of cases precludes us from making any formal recommendations about staging, we suggest that the finding of acellular mucin in a node should prompt evaluation of deeper levels (with or without cytokeratin immunohistochemistry) and submission of all pericolonic fat for additional lymph node harvest. Whether acellular mucin in nodes of untreated CRCs is related to the indolent biology of the disease, a robust local immune response or MMR deficiency requires further investigation.
摘要:
从治疗的结肠直肠癌(CRC)收获的具有无细胞粘蛋白的淋巴结被分期为pN0。然而,病理学家之间存在差异,同时报告pN阶段时,未治疗的CRC节点内发现无细胞粘蛋白。虽然UICC指南建议将其分期为pN1,但AJCC和CAP未提供任何建议。为了表征其临床病理特征和结果,我们比较了16个未治疗的CRC(研究组;平均年龄:68岁),其中淋巴结有无细胞粘蛋白,与34pN0和25pN1未治疗的CRC对照.所有肿瘤均为单灶;12例(75%)为右侧病变。大多数病例(75%)显示一个无细胞粘蛋白结节(范围:1-3)。与pN0(33%;p=0.006)和pN1对照(8%;p<0.001)相比,MMR缺陷型肿瘤在研究组(83%)中明显更常见。与pN1对照组相比,研究组患者的总生存期更接近pN0;然而,这一差异无统计学意义.总之,未经治疗的CRC,在淋巴结内含有无细胞粘液蛋白,通常表现为右侧,MMR缺陷型肿瘤在老年妇女中表现出非粘液性表型。虽然案件数量有限,使我们无法就分期提出任何正式建议,我们建议,在淋巴结中发现无细胞粘蛋白应促使评估更深层次的水平(有或没有细胞角蛋白免疫组织化学),并提交所有结肠周围脂肪以进行额外的淋巴结收获.未经治疗的CRC节点中的无细胞粘蛋白是否与疾病的惰性生物学有关,强烈的局部免疫反应或MMR缺陷需要进一步研究.