Department of Pathology, GROW School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands.
Department of Surgery, Maastricht University Medical Center+, Maastricht, The Netherlands.
Pathol Res Pract. 2020 Sep;216(9):153106. doi: 10.1016/j.prp.2020.153106. Epub 2020 Jul 11.
The size of regional, tumor draining lymph nodes without metastasis (LNneg) found in rectal cancer resection specimens varies and seems to be related to patient survival. Yet, the histopathological features influencing LNneg size in rectal cancer have not been studied in detail. Our pilot study focused on investigating the relationship between lymph node (LN) size and LNneg microarchitecture in rectal cancer (RC) resection specimens.
In this retrospective cohort study, resection specimens from 146 RC patients, treated with either surgery alone (n = 29) or neoadjuvant therapy followed by resection (n = 117), were included in the study. Histology of LNnegs was reviewed to establish number of lymphoid follicles and presence of intranodal fat. Longest long axis and area of each LN were measured digitally.
1830 LNnegs were measured. The microarchitecture was analyzed in a subset of 680 LNnegs. 153 (22.5 %) LNnegs contained intranodal fat. After neoadjuvant treatment, presence of intranodal fat was related to smaller LNneg area (median (range) area of LNneg without intranodal fat: 4.51 mm (0.15-46.89 mm), with intranodal fat: 3.46 mm (0.12-27.22 mm), p = 0.048). A higher number of lymphoid follicles was related to a larger LNneg area in both patient groups (p < 0.001).
Our pilot data suggest that in rectal cancer the presence of large regional LNnegs may reflect increased immune activation due to tumor related antigens. Further studies are warranted to investigate whether histologically visible microarchitectural features of LNnegs such as lymphoid follicles translate to particular features in radiological images and hence could potentially help to identify LNneg with more certainty at the time of pre-treatment disease staging.
在直肠癌切除标本中，无转移的区域性肿瘤引流淋巴结（LNneg）的大小存在差异，且似乎与患者的生存有关。然而，尚未详细研究影响直肠癌 LNneg 大小的组织病理学特征。我们的初步研究侧重于调查直肠癌（RC）切除标本中淋巴结（LN）大小与 LNneg 微观结构之间的关系。
在这项回顾性队列研究中，纳入了 146 例接受单纯手术治疗（n=29）或新辅助治疗后切除的 RC 患者的切除标本（n=117）。对 LNnegs 的组织学进行了复习，以确定淋巴滤泡的数量和淋巴结内脂肪的存在。数字测量每个 LN 的最长长轴和面积。
测量了 1830 个 LNnegs。对 680 个 LNnegs 的亚组进行了微观结构分析。153 个（22.5%）LNnegs 含有淋巴结内脂肪。新辅助治疗后，淋巴结内脂肪的存在与 LNneg 面积较小有关（无淋巴结内脂肪的 LNneg 中位数（范围）面积：4.51mm（0.15-46.89mm），有淋巴结内脂肪的 LNneg 面积：3.46mm（0.12-27.22mm），p=0.048）。在两组患者中，淋巴滤泡数量较多与 LNneg 面积较大相关（p<0.001）。
我们的初步数据表明，在直肠癌中，存在较大的区域性 LNneg 可能反映了肿瘤相关抗原引起的免疫激活增加。需要进一步研究来调查 LNnegs 的组织学可见微观结构特征（如淋巴滤泡）是否转化为放射图像中的特定特征，从而有可能帮助在治疗前疾病分期时更确定地识别 LNneg。
