Following the publication of the article 'The enhanced expression of the matrix metalloproteinase 9 in nasal NK/T-cell lymphoma. BMC Cancer 2007, 7:229' [1], the submitting author became aware that a co-author had been omitted from the publication. Therefore, this article has been submitted as a correction to the original text, and highlights the contributions that this author made to the original article. The author would like to apologize for any inconvenience this may have caused.

Corrected author list

Koh-ichi Sakata, Masanori Someya, Mutsuko Omatsu, Hiroko Asanuma, Tadashi Hasegawa, Shingo Ichimiya, Masato Hareyama, and Tetsuo Himi.