Ground-glass opacity showed response to immunotherapy in cancer patients.

e14605 Background: Ground glass opacities (GGO) are lesions with hazy density on CT. Immune checkpoint inhibitors (ICIs) achieved a significant improvement in the treatment of early and advanced non-small lung cancer (NSCLC). It is unclear whether ICI therapy show efficacy on GGO lesions. Methods: As the largest diameter of most lesions was less than 10mm, the definition of evaluable lesion we expanded the lower limit of the diameter to 4 mm. We retrospectively assessed cancer patients with GGOs who underwent at least two courses of immunotherapy between January 2016 and June 2021 in Second Xiangya hospital, China. Also, we evaluated GGOs that had been examined by low-dose thin-slice CT more than twice. Wilcoxon test was used to evaluate the length and diameter changes of GGO. We assessed the correlation between CT imaging features of GGO and the efficacy of immunotherapy through univariate and multivariate logistic regression. Results: Among eligible patients (n = 51), 35 were lung cancer patients and 16 were other tumor patients. Confirmed 95 GGOs were included. 68 GGOs were from lung cancer patients and 27 GGOs were from patients with other types of cancer (such as esophageal carcinoma, oral squamous cell carcinoma and hepatocarcinoma etc.). The diameter of GGO decreased significantly after immunotherapy (7.56 vs 4.31, P = 0.000). The same results were observed in lung cancer patients (7.98mm vs 4.92mm, P = 0.000) and in non-lung cancer patients (6.90mm vs 3.35mm, P = 0.001). The volume of GGO shirked significantly after immunotherapy in cancer patients (297.35mm3 vs 125.46mm3, P = 0.000) lung cancer patients (401.41 mm3 vs 164.91 mm3, P = 0.007) and non-lung cancer patients (137.93mm3 vs 65.04mm3, P = 0.000). Conclusions: GGO can response to immunotherapy, which indicates immunotherapy maybe potentially helpful for patients with multiple GGO lesions such as multiple primary lung cancer (MPLC) patients.