On the other hand, for different tumor types, one could expect some differences in tumors' vascularity/leakiness, pH, blood protein etc. Thus, observed close similarity between the fluorescence lifetimes from tumor areas in the cases of HER2 positive tumors, imaged with non-specific probe, and HER2 negative tumors, imaged with similar, but HER2 specific probes (see Figs. 4, 7 and 6), further emphasizes the importance of the probe binding to HER2 receptors for fluorescence lifetime to decrease, indicating that all other mentioned above factors play relatively minor role. The gene discussed is ERBB2; the disease is neoplasm.