Becherucci Giulia, Ruffolo Cesare, Scarpa Melania, Scognamiglio Federico, Stepanyan Astghik, Maretto Isacco, Kotsafti Andromachi, De Simoni Ottavia, Pilati Pierluigi, Franzato Boris, Scapinello Antonio, Bergamo Francesca, Massani Marco, Stecca Tommaso, Pozza Anna, Cataldo Ivana, Brignola Stefano, Pellegrini Valerio, Fassan Matteo, Guzzardo Vincenza, Dal Santo Luca, Salmaso Roberta, Carlotta Ceccon, Dei Tos Angelo Paolo, Angriman Imerio, Spolverato Gaya, Chiminazzo Valentina, Negro Silvia, Vignotto Chiara, Marchegiani Francesco, Facci Luca, Rivella Giorgio, Bao Quoc Riccardo, Baldo Andrea, Pucciarelli Salvatore, Zizzo Maurizio, Businello Gianluca, Salmaso Beatrice, Parini Dario, Pirozzolo Giovanni, Recordare Alfonso, Tagliente Giovanni, Bordignon Giovanni, Merenda Roberto, Licia Laurino, Pozza Giulia, Godina Mario, Mondi Isabella, Verdi Daunia, Da Lio Corrado, Guerriero Silvio, Piccioli Alessandra, Portale Giuseppe, Zuin Matteo, Cipollari Chiara, Noaro Giulia, Cola Roberto, Candioli Salvatore, Gavagna Laura, Ricagna Fabio, Ortenzi Monica, Guerrieri Mario, Tomassi Monica, Tedeschi Umberto, Marinelli Laura, Barbareschi Mattia, Bertalot Giovanni, Brolese Alberto, Ceccarini Lavinia, Antoniutti Michele, Porzionato Andrea, Agostini Marco, Cavallin Francesco, Tussardi Gaia, Di Camillo Barbara, Bardini Romeo, Castagliuolo Ignazio, Scarpa Marco
General Surgery Unit, Azienda ULSS 1 Dolomiti, Belluno, Italy.
Chirurgia Generale 3 Unit, Azienda Ospedale Università di Padova, Padova, Italy.
Surgery. 2025 Feb;178:108902. doi: 10.1016/j.surg.2024.09.043. Epub 2024 Nov 20.
Transanal excision of rectal cancer can be considered the definitive surgical treatment if the depth spread is T1 or lower, and the lesion is completely included within the resection margin. This study aims to analyze the immune microenvironment in healthy rectal mucosa as a possible predictor of tumor infiltration depth, lateral tumor spread, and recurrence of rectal cancer after transanal local excision.
This study is a subanalysis of data from the IMMUNOREACT 1 and 2 trials (NCT04915326 and NCT04917263, respectively) including all the patients who underwent transanal excision of rectal cancer. This multicentric study collected healthy mucosa surrounding the neoplasms of patients with rectal cancer. A panel of immune markers was investigated at immunohistochemistry: CD3, CD4, CD8, CD8β, Tbet, FoxP3, PD-L1, MSH6, and PMS2 and CD80. Flow cytometry determined the proportion of epithelial cells expressing CD80, CD86, CD40, HLA ABC or HLA DR and the proportion of activated CD8+ T cells, CD4+ Th1 cells, and Treg.
Receiver operating characteristic curve analysis for predicting deep tumor spread showed an area under the curve of 0.70 (95% confidence interval: 0.60-0.80) for CD25+FoxP3+ cell rate and 0.74 (95% confidence interval: 0.53-0.92) for CK+CD86+ cell rate. Receiver operating characteristic curve analysis for predicting lateral tumor spread showed an area under the curve of 0.82 (95% confidence interval: 0.61-0.99) for CD8+CD38+ MFI, 0.96 (95% confidence interval: 0.85-0.99) for CD8β infiltration, and 0.97 (95% confidence interval: 0.87-0.99) for CK+HLAabc+ cell rate. Receiver operating characteristic curve analysis for predicting recurrence showed an area under the curve of 0.93 (95% confidence interval: 0.76-0.99) for CD8+CD38+ MFI and 0.94 (95% confidence interval: 0.78-0.99) for CD8+CD28+ MFI. Low CD8+CD38+ MFI and low CD8+CD28+ MFI were associated with shorter disease-free survival (P = .025 and P = .021, respectively).
Our study showed that the association between the high proportion of epithelial cells acting as presenting cells and deep or lateral tumor spread may be explained by the presence of a greater tumor load at the site. Moreover, it showed that weak activation of CD8+ T cells within the rectal mucosa is associated with lateral tumor spread and eventually a higher recurrence rate. The mucosal level of CD8β infiltration detected at immunohistochemistry might be tested as a marker of lateral tumor spread and potentially translated into clinical practice.
如果直肠癌的深度浸润为T1或更低，且病变完全包含在切除边缘内，则经肛门切除可被视为确定性手术治疗。本研究旨在分析健康直肠黏膜中的免疫微环境，作为经肛门局部切除术后肿瘤浸润深度、肿瘤侧向扩散和直肠癌复发的可能预测指标。
本研究是对IMMUNOREACT 1和2试验（分别为NCT04915326和NCT04917263）数据的亚分析，纳入了所有接受直肠癌经肛门切除的患者。这项多中心研究收集了直肠癌患者肿瘤周围的健康黏膜。通过免疫组织化学研究一组免疫标志物：CD3、CD4、CD8、CD8β、Tbet、FoxP3、PD-L1、MSH6、PMS2和CD80。流式细胞术测定表达CD80、CD86、CD40、HLA ABC或HLA DR的上皮细胞比例以及活化的CD8 + T细胞、CD4 + Th1细胞和调节性T细胞的比例。
预测肿瘤深度扩散的受试者工作特征曲线分析显示，CD25 + FoxP3 +细胞率的曲线下面积为0.70（95%置信区间：0.60 - 0.80），CK + CD86 +细胞率的曲线下面积为0.74（95%置信区间：0.53 - 0.92）。预测肿瘤侧向扩散的受试者工作特征曲线分析显示，CD8 + CD38 +平均荧光强度（MFI）的曲线下面积为0.82（95%置信区间：0.61 - 0.99），CD8β浸润的曲线下面积为0.96（95%置信区间：0.85 - 0.99），CK + HLAabc +细胞率的曲线下面积为0.97（95%置信区间：0.87 - 0.99）。预测复发的受试者工作特征曲线分析显示，CD8 + CD38 + MFI的曲线下面积为0.93（95%置信区间：0.76 - 0.99），CD8 + CD28 + MFI的曲线下面积为0.94（95%置信区间：0.78 - 0.99）。低CD8 + CD38 + MFI和低CD8 + CD28 + MFI与无病生存期缩短相关（分别为P = 0.025和P = 0.021）。
我们的研究表明，作为呈递细胞的上皮细胞比例高与肿瘤深度或侧向扩散之间的关联可能是由于该部位存在更大的肿瘤负荷。此外，研究表明直肠黏膜内CD8 + T细胞的弱活化与肿瘤侧向扩散相关，并最终导致更高的复发率。免疫组织化学检测到的CD8β浸润的黏膜水平可作为肿瘤侧向扩散的标志物进行检测，并有可能转化为临床实践。
