目前逆转剂在头颈部肿瘤的MDR研究主要集中在右维拉帕米(dexverapamil)对恶性淋巴瘤MDR的逆转上。右维拉帕米对心血管毒性小于维拉帕米，因此它更易被临床接受。右维拉帕米早已被证明能提高肿瘤细胞中多柔比星(doxorubicin)的浓度。Wilson等［18］对65位接受了右维拉帕米与EPOCH方案(包括依托泊苷、泼尼松、长春新碱、环磷酰胺、多柔比星)联合化疗的恶性淋巴瘤病人进行了研究，发现右维拉帕米将多柔比星的浓度提高了近2倍。此外，Wilson等［19］在另外154位恶性淋巴瘤病人的研究中得到类似的结论。
总之，经过对MDR机制的深入研究，现在已取得了一些重要发现，在其临床如何克服MDR方面也取得一定进展，但其效果不尽人意。而且对于头颈部肿瘤的MDR研究仍较少，有关逆转剂的报道也不多。因此，对于头颈部MDR逆转剂的研究是今后我们克服化疗耐药研究的主要方向之一。
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