Department of Pathology and GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands.
Department of Surgery, Maastricht University Medical Center+, Maastricht, The Netherlands.
Colorectal Dis. 2018 Nov;20(11):1014-1019. doi: 10.1111/codi.14335. Epub 2018 Jul 28.
Lymph node (LN) status is key to determining the need for adjuvant therapy in colorectal cancer (CRC) and for disease which has progressed to Stage II (T3-T4, N0, M0). A yield of fewer than 12 LNs is considered a risk factor similar to high-grade histology and vascular, lymphatic and perineural invasion. The aim of this retrospective study was to investigate the effect of acetone fat clearance of the mesocolon or mesorectum on LN yield and the identification of patients with high-risk Stage II CRC.
After conventional LN retrieval, fatty tissue derived from the mesocolon or mesorectum of 80 CRC specimens was incubated in acetone for 24 h. A second dissection was then performed by a trained technician. The total number of LNs as well as tumour involvement (LNpositive and LNnegative) were assessed at each stage. In addition, LN morphology was assessed and clinicopathological data were extracted from existing pathology reports.
Eighty CRC specimens were available for study. 1548 (94%) LN were negative and 96 (6%) were positive. The median (range) LN yield per specimen was 12 (3-41) LN increasing to 18 (4-48) LN after fat clearance (P < 0.001). After fat clearance, 534 additional LNs were identified in 75 (94%) of the specimens, and all but 10 were negative. The pN stage did not change in six patients who were found to be LN positive after fat clearance. However, the number of high-risk Stage II CRC patients decreased from 11 to 7. Although important for these patients, this downstaging did not reach statistical significance (P = 0.125).
Acetone clearance of mesocolic or mesorectal fat increases median LN yield and may in a larger study decrease the number of patients classified as having high-risk Stage II CRC.
淋巴结（LN）状态是决定结直肠癌（CRC）辅助治疗必要性以及疾病进展至 II 期（T3-T4、N0、M0）的关键因素。LN 检出数少于 12 个被认为是一种危险因素，类似于高级别组织学、血管、淋巴和神经周围浸润。本回顾性研究旨在探讨乙腈清除结直肠系膜或直肠系膜脂肪对 LN 检出数的影响，并确定高危 II 期 CRC 患者。
在常规 LN 检索后，将 80 例 CRC 标本的结肠系膜或直肠系膜脂肪组织置于乙腈中孵育 24 小时。然后由经过培训的技术人员进行二次解剖。在每个阶段评估总 LN 数量以及肿瘤受累情况（LN 阳性和 LN 阴性）。此外，评估 LN 形态，并从现有病理报告中提取临床病理数据。
80 例 CRC 标本可用于研究。1548 个（94%）LN 为阴性，96 个（6%）为阳性。每个标本的 LN 检出中位数（范围）为 12（3-41）个，经脂肪清除后增至 18（4-48）个（P<0.001）。脂肪清除后，75 例标本中有 534 个额外的 LN 被识别，除 10 个外均为阴性。在脂肪清除后发现 LN 阳性的 6 例患者中，pN 分期没有改变。然而，高危 II 期 CRC 患者的数量从 11 例减少至 7 例。尽管这对这些患者很重要，但这种降期并没有达到统计学意义（P=0.125）。
乙腈清除结直肠系膜或直肠系膜脂肪可增加 LN 检出中位数，在更大的研究中可能会减少被归类为高危 II 期 CRC 的患者数量。
