SP7 and neoplasm: Linear by linear χ 2 tests were performed to identify linear trends; low levels of nuclear expression of osterix had a significant trend with increasing tumour grade (χ2 = 12.969, d.f.=2, P < 0.001), increasing pleomorphism variation score (χ2 = 7.120, d.f.=2, P = 0.008), and worse NPI prognostic group (χ2 = 10.831, d.f.=2, P < 0.001) at the time of presentation; data is shown in Table 1.