Clinical relevance of flow cytometric immunophenotyping of the cerebrospinal fluid in patients with diffuse large B-cell lymphoma.

BACKGROUND: Central nervous system (CNS) relapse is an uncommon but dramatic complication of diffuse large B-cell lymphoma (DLBCL). Several studies have demonstrated the superiority of cerebrospinal fluid (CSF) flow cytometry (FCM), as compared with conventional cytology (CC), in detecting occult leptomeningeal disease. The clinical relevance of a positive FCM still has to be clarified. PATIENTS AND METHODS: We analyzed CSF from 114 DLBCL patients at diagnosis (n = 95) or at relapse (n = 19) by FCM and CC. Most patients received meningeal prophylaxis. FCM results did not influence treatment strategies. RESULTS: Fourteen samples were FCM+, versus one CC+ (also FCM+). Within all patients without neurological symptoms (n = 101), four (4%) relapsed in the CNS, with a median time to relapse of 5.2 months. Only one-fourth (25%) was FCM+ before relapse. More than one extranodal disease site and elevated lactate dehydrogenase levels were associated with an increased risk of CNS relapse. CONCLUSIONS: FCM gives far more positive results than CC. However, a positive FCM result did not translate into a significant increase in CNS relapse rate in this histologically uniform population receiving CNS prophylaxis.

Response assessment after an inductive CHOP or CHOP-like regimen with or without rituximab in 103 patients with diffuse large B-cell lymphoma: integrating 18fluorodeoxyglucose positron emission tomography to the International Workshop Criteria.

BACKGROUND: Revised response criteria for aggressive lymphomas have been proposed (Cheson, J Clin Oncol, 2007) stressing the role of (18)fluorodeoxyglucose-positron emission tomography (PET) in posttreatment evaluation. The value of PET after four cycles compared with the International Workshop Criteria (IWC) remains to be established. PATIENTS AND METHODS: In all, 103 patients with untreated diffuse large B-cell lymphoma were prospectively enrolled to evaluate the prognostic impact of PET after two and four cycles. RESULTS: Median age was 53 years (19-79), 68% male. The International Prognostic Index was low=22%, low-intermediate=19%, intermediate-high=33% and high risk=26%. Treatment consisted of cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) (30%) or dose-intensified CHOP (70%), with rituximab (49%) or without (51%). Ninety-nine patients were evaluated by PET and IWC at four cycles: 77 (78%) had a negative PET, while 22 (22%) remained positive. The 5-year event-free survival (EFS) was 36% for patients with a positive PET versus 80% with a negative examination, whatever the response [complete response (CR) versus partial response (PR)] according to IWC (P<0.0001). Positive PET patients had a 5-year EFS of 58% if in CR/CR unconfirmed by IWC and 0% if not (P<0.0001). The same observations could be made in patients treated with and without rituximab. CONCLUSION: The integration of PET in treatment evaluation offers a powerful tool to predict outcome.

Rituximab, gemcitabine and oxaliplatin: an effective salvage regimen for patients with relapsed or refractory B-cell lymphoma not candidates for high-dose therapy.

BACKGROUND: High-dose therapy (HDT) with stem-cell support is the reference treatment for relapsed lymphoma, but is not appropriate for all patients. Conventional salvage chemotherapies have been used with limited efficacy and significant toxicity. Rituximab, gemcitabine and oxaliplatin are active as single agents in relapsed or refractory lymphoma, and have demonstrated synergistic effects in vitro and in vivo. PATIENTS AND METHODS: Forty-six patients with relapsed or refractory B-cell lymphoma received up to eight cycles of R-GemOx (rituximab 375 mg/m(2) on day 1, gemcitabine 1000 mg/m(2) and oxaliplatin 100 mg/m(2) on day 2). The majority (72%) had diffuse large B-cell lymphoma. RESULTS: After four cycles of R-GemOx, the overall response rate was 83% [50% complete response (CR)/unconfirmed CR (CRu)]. High CR/CRu rates were observed in all histological subtypes. In patients who had previously received rituximab, the CR/CRu rate after eight cycles was 65%. The 2-year event-free and overall survival rates (median follow-up of 28 months) were 43% and 66%, respectively. Among responders, the probability of being disease free for 2 years was 62%. Treatment was generally well tolerated. CONCLUSION: R-GemOx shows promising activity with acceptable toxicity in patients with relapsed/refractory B-cell lymphoma who are not eligible for HDT.