Inclusion Criteria:

- histologically-proven mantle cell lymphoma;

- previously untreated disease at stage II, III and IV, requiring therapy.

Exclusion Criteria:

- known hypersensitivity reaction to rituximab, or known anti-murine antibody
reactivity or known hypersensitivity to murine antibodies;

- active malignancy other than mantle cell lymphoma within 5 years of start of study,
with the exception of resected basal cell cancer, squamous cell cancer of the skin,
or in situ cancer of the cervix;

- serious disorders interfering with full standard dosing chemotherapy;

- stage I disease.