Department of Obstetrics and Gynecology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Department of Pathology, Kagoshima University Hospital, Kagoshima, Japan.
Cytopathology. 2023 May;34(3):211-218. doi: 10.1111/cyt.13215. Epub 2023 Feb 28.
For patients with endometrial cancer, the POLE (polymerase epsilon) mutation (POLEmut)-subtype, one of four molecular-analysis-based categories in the Cancer Genome Atlas (TCGA), has the best prognosis. The following histological characteristics are typically observed in endometroid carcinoma cases with the POLEmut-subtype: (1) the presence of tumour giant cells, (2) numerous tumour-infiltrating lymphocytes (TILs) and/or peri-tumoral lymphocytes, and (3) a high grade. However, in the context of cytology, the morphological characteristics of this subtype remain unknown.
DNA extracted from formalin-fixed paraffin-embedded (FFPE) tissues was subjected to next-generation sequencing analysis and categorised according to the TCGA classifications. Genomic mutation, tumour mutation burden (TMB), and microsatellite instability were also assessed. Cytological specimens of resected uteri obtained using the Papanicolaou method were histologically separated into three types.
Seven out of 112 patients (6%) with endometrial cancer were diagnosed with the POLEmut-subtype between January 2019 and August 2021. Tumour giant cells were observed in three cases (43%) on histology and cytology. TIL and/or peritumoral lymphocytes with inflammatory cells were detected in five cases (71%) on histology and three cases (43%) on cytology. Cases in which these three characteristics were observed on both cytology and histology may have belonged to the POLEmut-subtype. There were no cases in which these characteristics were absent on histology but present on cytology. TMB tended to be higher in cases when the three characteristics were observed in both cytological and histological findings.
Preoperative endometrial cytology highlighted the characteristics of the POLEmut-subtype in the histological analysis of resected uterine specimens and has the potential to play an important role in treatment decisions.
在子宫内膜癌患者中，POLE（聚合酶 epsilon）突变（POLEmut）亚型是癌症基因组图谱（TCGA）基于四种分子分析类别之一，具有最佳的预后。POLEmut 亚型的子宫内膜样癌通常具有以下组织学特征：（1）存在肿瘤巨细胞，（2）大量肿瘤浸润淋巴细胞（TIL）和/或肿瘤周围淋巴细胞，（3）高级别。然而，在细胞学背景下，这种亚型的形态特征尚不清楚。
从福尔马林固定石蜡包埋（FFPE）组织中提取 DNA，进行下一代测序分析，并根据 TCGA 分类进行分类。还评估了基因组突变、肿瘤突变负担（TMB）和微卫星不稳定性。采用巴氏涂片法切除的子宫细胞学标本经组织学分为三种类型。
2019 年 1 月至 2021 年 8 月期间，112 例子宫内膜癌患者中有 7 例（6%）诊断为 POLEmut 亚型。组织学和细胞学上均观察到 3 例（43%）存在肿瘤巨细胞。组织学上观察到 5 例（71%）和细胞学上观察到 3 例（43%）存在 TIL 和/或肿瘤周围淋巴细胞伴炎症细胞。细胞学和组织学均观察到这三种特征的病例可能属于 POLEmut 亚型。组织学上不存在这些特征但细胞学上存在的病例。在细胞学和组织学发现均观察到这三种特征的情况下，TMB 倾向于更高。
术前子宫内膜细胞学突出了切除子宫标本组织学分析中 POLEmut 亚型的特征，并有可能在治疗决策中发挥重要作用。
