Immunohistochemical Estimates of Angiogenesis, Proliferative Activity, p53 Expression, and Multiple Drug Resistance Have No Prognostic Impact in Osteosarcoma: A Comparative Clinicopathological Investigation

Table 5

Multiple drug resistance (Pgp expression) in 37 osteosarcomas in pre- and post-chemotherapy biopsies, respectively^a. P value^c=.10.

Pre-chemotherapy MDR-score^b	Post-chemotherapy MDR-score^b		∑
	<2	≥2
<2	20	1	21
≥2	5	11	16
∑	25	12	37

^aThree cases could not be evaluated in the post-chemotherapy specimens, and 6 cases were associated with 100% tumor necrosis.
^bMDR-score ≥2 indicates resistance to chemotherapy.
^cMcNemar’s test.