Inclusion Criteria:

- Age 18-65

- Histologically documented diagnosis of grade I-IIIa FL defined according to WHO
guidelines 2008 (Re-biopsy required)

- Availability of BM and PB for Minimal Residual Disease (MRD) analysis (see Appendix
I)

- Relapsed or refractory disease after ≤ two chemotherapy lines at least one containing
Rituximab (Rituximab maintenance is UNOTU considered a therapeutic line)

- Clinical indication of treatment i.e. Stage II-IV who require therapy according to
SIE and GELF criteria (see Appendix II)

- ECOG performance status 0-2 (unless disease-related) (see Appendix III)

- Availability of histological material for centralized revision

- Laboratory values:

- ANC ≥ 1500/mmc unless due to marrow involvement by lymphoma and/or platelets ≥
100000/mmc unless due to marrow involvement by lymphoma

- Serum creatinine ≤ 1.5 x ULN, unless it is disease related

- Bilirubin ≤ 1.5 x ULN (or ≤ 3.0 x ULN, if patient has Gilbert syndrome)

- AST/SGOT and/or ALT/SGPT ≤ 2.5 x ULN if not lymphoma related or ≤ 5.0 x ULN in
case of lymphoma liver involvement

- Adequate cardiac function: LVEF > 50% by echocardiography or MUGA scan

- Not pregnant or breast-feeding

- Willingness to use effective contraception during the study and 3 months after the
end of treatment

- No other prior malignancies except for adequately treated non-melanoma skin cancer,
carcinoma in situ of the cervix, or other cancer from which the patient has been
disease-free for ≥ 5 years (see Exclusion criteria 14)

- Signed informed written consent

Exclusion Criteria:

- Grade IIIb FL, transformed FL or histologies different from FL

- Previous treatment with > two lines of chemotherapy ± rituximab Maintenance is UNOTU
considered a therapeutics line)

- Previous ASCT or RIT treatment

- CNS involvement by lymphoma

- HBV positivity with the exception of patients who are seropositive because of
hepatitis B virus vaccination and patients HbcAb positive and HbsAg negative with
undetectable serum HBV-DNA. Occult carriers: must receive treatment with Lamivudine
100 mg for the duration of treatment program and at least 12 months after treatment
cessation; HBV-DNA levels and HBsAg will be monitored every month

- HCV positivity with elevated transaminases or INR or APTT or active virus replication

- HIV positivity

- Any concurrent medical condition requiring long term use (> one month) of systemic
corticosteroids

- Active bacterial, viral, or fungal infection requiring systemic therapy

- Any concurrent medical or psychiatric condition which might impair administration of
therapy or preclude the ability to give informed consent

- Treatment with an experimental agent within 30 days prior to study entry

- Myelosuppressive chemo or biological therapy within three weeks before study entry
(use rituximab course delivered as maintenance is not an exclusion therapy)

- Major surgery other than diagnosis within 4 weeks prior to study entry