Abstract 3806: Impact of tumor-infiltrating lymphocytes, tertiary lymphoid structures, and neutrophil-to-lymphocyte ratio on the prognosis of patients with lung metastases from uterine leiomyosarcoma

Abstract In the tumor microenvironment, tumor-infiltrating lymphocytes (TILs) and tertiary lymphoid structures (TLSs) are known to play a major role in terms of antitumor immunity. It has been reported that the presence of TILs and TLSs is related to the prognosis of various cancers. In addition, neutrophil-to-lymphocyte ratio (NLR) has also been associated with the prognosis in them. We investigated the significance of TILs, TLSs and NLR as a prognosis indicator for lung metastases from uterine leiomyosarcoma. We retrospectively recruited 102 patients undergoing metastasetomy for lung metastases from uterine leiomyosarcoma at Okayama University Hospital from January 2006 to December 2019. TILs were evaluated by immunohistochemical staining of surgically resected specimens of lung metastases using anti-CD3/CD8/CD103/Foxp3 antibodies. TLSs were also evaluated using anti-CD20 antibodies. We counted the number of CD3/CD8/CD103/Foxp3-positive cells and classified TILs into high and low groups. We measured the density of CD20-positive cells and classified TLSs into high- and low-density groups. NLR was calculated from the blood examination immediately before the most recent pulmonary metastasectomy. We determined the cut-off value for NLR using a time-dependent receiver operating characteristic (ROC) curve analysis and classified the patients into NLR-high and NLR-low groups according to the cut-off value. In terms of TILs, both CD3 and CD8 were correlated with the prognosis. The overall survival (OS) was significantly better in patients with CD3-high group (p = 0.018), CD8-high group (p = 0.017), TLSs-high group (p = 0.041) and NLR-low group (p = 0.018), respectively. The status of CD103 and Foxp3 did not affect the prognosis. We assessed the impact of the combination of CD8-positive TILs or TLSs and NLR on the prognosis. Regarding CD8-positive TILs and NLR, the OS of CD8-high/NLR-low group was significantly better than that of CD8-low/NLR-high group (p = 0.0078). In terms of TLSs and NLR, the OS of TLSs-high/NLR low group was significantly better than that of TLSs-low/NLR-high group (p = 0.010). In conclusion, CD3-positive TILs, CD8-positive TILs, TLSs, and NLR are correlated with the prognosis, respectively. The combination of CD8-positive TILs or TLSs and NLR may be indicators to predict the prognosis of the patients with lung metastases from uterine leiomyosarcoma. Citation Format: Fumiaki Mukohara, Naoki Matsuda, Hiromasa Yamamoto, Tomohiro Habu, Daisuke Mizuno, Ryo Yoshichika, Atsushi Matsuoka, Tomoaki Higashihara, Naohiro Hayashi, Mao Yoshikawa, Masayoshi Ohki, Kazuhiko Shien, Ken Suzawa, Katsuhito Takahashi, Shinichi Toyooka. Impact of tumor-infiltrating lymphocytes, tertiary lymphoid structures, and neutrophil-to-lymphocyte ratio on the prognosis of patients with lung metastases from uterine leiomyosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3806.