Figure 3B and Table 1 illustrate the biodistribution of 68Ga-NOTA-MAL-Cys-MZHER2:342 in Calu-3-bearing mice. The tumor uptake was 16.11 ± 3.91 %ID/g, while uptake in the heart, liver, lung, and kidney was 0.5 ± 0.03, 3.55 ± 0.73, 2.44 ± 1.07, and 106.85 ± 0.61 %ID/g, respectively (n = 3). The tumor-to-blood and tumor-to-muscle uptake ratios were calculated to be 24.29 ± 1.93 and 35.77 ± 2.14, respectively. HER2 expression in tumor tissues was further evaluated through immunohistochemical assays, which revealed high expression levels (Figure 3C). The gene discussed is ERBB2; the disease is neoplasm.