Box plots presenting tumor infiltrating CD8⁺ and Foxp3⁺ cells for different groups of TSCC.

A) number of CD8⁺ TILs, B) number Foxp3⁺ TILs and C) the CD8⁺/Foxp3⁺ cell ratio. “Good” and “poor” denotes clinical outcome. In addition to the four TSCC groups defined in the Methods section, different combinations of groups have also been compared. Thus, “HPV⁺ good” corresponds to group A; “HPV⁺ poor” to group B; “HPV⁻ good” to group C; “HPV⁻ poor” to group D; HPV⁺ to groups A+B, HPV⁻ to groups C+D; “good” to groups A+C; and “poor” to groups B+D. In order to better visualize the details in the lower part of Figure 1C the upper part of the diagram including the upper whisker (at a ratio of 80) was omitted.