The prognostic impact of a high number of peritumoral alveolar macrophages in neuroendocrine carcinoma in the lung
Takehiko Tanaka, Shigeki Umemura, Tomohiro Miyoshi, Tokiko Nakai, Osamu Noritake, Jun Suzuki, Kenta Tane, Joji Samejima, Keiju Aokage, Sachiyo Mimaki, Katsuya Tsuchihara, Tetsuro Taki, Saori Miyazaki, Reiko Watanabe, Shingo Sakashita, Naoya Sakamoto, Motohiro Kojima, Koichi Goto, Norihiko Ikeda, Masahiro Tsuboi, Genichiro Ishii- General Medicine
- Pathology and Forensic Medicine
Abstract
Alveolar macrophages (AMs) are resident macrophages in the lungs; however, whether the number of AMs plays a role in the lung neuroendocrine tumor (NET) prognosis remains unclear. We counted the number of AMs located around the tumor (peritumoral alveolar macrophages [pAMs]) and the number of AMs located apart from the tumor (distant macrophages; dAMs). In 73 cases of neuroendocrine carcinoma (NEC: small cell lung carcinoma and large cell neuroendocrine carcinoma), the group that contained higher pAMs (≥86/μm2) revealed shorter recurrent‐free survival (RFS) than those with lower pAMs (<86/μm2) (p = 0.005). Bivariate analysis showed that the number of pAMs was an independent predictor of a poor RFS. In contrast, in the carcinoid tumor cohort (n = 29), there was no statistically significant correlation between the two groups with high and low numbers of pAMs in RFS (p = 0.113). Furthermore, we examined the correlation between genomic alterations and the number of pAMs in NEC, but no significant correlation was observed. In conclusion, the number of pAMs is a prognostic factor for NEC in the lung and pAMs may contribute to tumor progression within the peritumoral microenvironment.