case_images: PMC9755663_01
case_images: Imaging data of the patient during treatment. CT examination of the chest showed partial response (PR) after chemoradiotherapy. (A) The initial CT scan of the patient demonstrated a lesion in the right upper lobe of the lung with enlarged right mediastinal lymph nodes and extracapsular invasion; (B) CT scan showed PR of the lesions 1 month after chemoradiation; multiple metastases arising after the use of durvalumab demonstrating a hyperprogressive disease. CT images show (C) liver metastasis, (D) pancreatic metastasis, and (E) lumbar metastasis. MR images show (F) brain and meningeal metastases and (G-I) myocardial metastases. (J) Patient treatment chart.
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case_images: Figure 1A ). CT re-examination showed good changes in the right lung cancer and mediastinal lymph nodes after treatment, and the patient had a partial response (PR) according to RECIST criteria 1.1 ( Figure 1B ). Systemic re-examinations showed liver metastases, pancreatic metastases, and multiple intra-abdominal metastases ( Figures 1C, D ). Magnetic resonance imaging (MRI) results of the head and spine showed multiple spinal metastases in the bone ( Figure 1E ) and brain and meningeal metastases in the central nervous system ( Figure 1F ). Cardiac MRI and ultrasound findings showed very rare myocardial metastases ( Figures 1G-I ). The overall treatment process diagram is shown in  Figure 1J .
case_images: Multiplex immunohistochemistry (mIHC) results of lesion specimens and tumor mutation burden (TMB) and PD-L1 detection. (A) Dynamic changes in tumor mutation burden of the lung, blood, and liver. Definition of tissue tumor mutation burden (tTMB) and blood tumor mutation burden (bTMB): the TMB was defined as the number of somatic, coding, base substitutions, and indel mutations per megabases of the genome examined; bTMB and tTMB were calculated based on the candidate mutations according to the following formula: Absolute mutation count x 1,000,000/Panel exonic base num. (B) PD-L1 protein expression in paraffin sections of the primary lesion. (C) Representative images of CD8, CD68, PD-1, PD-L1, and CD163 shown by mIHC in the primary tumor. Nuclei (blue) were counterstained by DAPI. The original magnification was x200. (D) Quantification results of mIHC of the primary lesion. (E) Representative images of CD8, CD68, PD-1, PD-L1, and CD163 shown by mIHC in liver metastatic tumors. Nuclei (blue) were counterstained by DAPI. The original magnification was x200. (F) Quantification results of mIHC of liver metastases. (G) Representative images of CD33+CD11b+ and FoxP3+ in primary and liver metastatic tumors. Nuclei (blue) were counterstained by DAPI. The original magnification was x200. (H) Quantification results of myeloid-derived suppressor cells and regulatory T cells.
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case_images: In addition, genetic testing showed that the patient's plasma and tissue tumor mutational load (TMB) values have been very low ( Figure 2A ). In the primary lung baseline tissue, the expression level of PD-L1-positive cells accounted for 80% of the tumor cells ( Figure 2B ). As shown in  Figure 2C , CD8+ lymphocytes and CD68+ macrophages were observed with high infiltration in the baseline tissue microenvironment. T cells, CD8+PD-L1+ T cells, and CD8+PD-1+ T cells accounted for 9.75%, 9.32%, and 1.81% and 15.95%, 10.11%, and 5.42% in the tumor and stroma regions, respectively ( Figure 2D ). This showed the high percentage of CD8+PD-L1+ T cells in the tumor region as 95.5% (9.32%/9.75%) of CD8+ cells expressed PD-L1. Moreover, CD68+CD163+ accounted for 9.69% and 3.21% in the tumor and stroma regions ( Figure 2D ). Examination of the immune microenvironment in the liver metastasis revealed a high degree of CD8+ and CD68+ cell infiltration ( Figure 2E ). Quantitative analysis revealed that CD8+ T cells, CD8+PD-L1+ T cells, and CD8+PD-1+ T cells accounted for 26.74%, 22.89%, and 0% and 93.24%, 63.89%, and 0% in the tumor and stroma regions, respectively ( Figure 2F ). It could also be seen in  Figure 2F  that a high percentage of CD8+PD-L1+ T cells was infiltrated in the tumor region as 85.6% (22.89%/26.74%) of CD8+ cells expressed PD-L1 with nearly no CD8+PD-1+ T cells. Moreover, CD68+CD163+ accounted for 12.40% and 6.87% in the tumor and stroma regions ( Figure 2F ). Notably, MDSC levels were significantly increased and Treg levels were markedly decreased in liver metastases than in the primary tumor ( Figures 2G, H ).