Strikingly high false positivity of surveillance FDG-PET/CT scanning among patients with diffuse large cell lymphoma in the rituximab era.

Predictive value (PV) of surveillance fluorodeoxyglucose positron emission tomography (FDG-PET) in patients with diffuse large B-cell lymphoma (DLBCL) treated with chemotherapy-rituximab (R) versus chemotherapy only, remains unclear. The aim of the current study was to compare the performance of surveillance PET in DLBCL patients receiving CHOP (cyclophosphamide, hydroxydaunorubicin hydrochloride, vincristine, and prednisone) alone versus CHOP-R. Institutional database was retrospectively searched for adults with newly diagnosed DLBCL, receiving CHOP or CHOP-R, who achieved complete remission and underwent surveillance PETs. Follow-up (FU) PET was considered positive for recurrence in case of an uptake unrelated to physiological or known benign process. Results were confirmed by biopsy, imaging and clinical FU. One hundred nineteen patients, 35 receiving CHOP and 84 CHOP-R, who underwent 422 FU-PETs, were analyzed. At a median PET-FU of 3.4 years, 31 patients relapsed (17 vs. 14, respectively; P = 0.02). PET detected all relapses, with no false-negative studies. Specificity and positive PV (PPV) were significantly lower for patients receiving CHOP-R vs. CHOP (84% vs. 87%, P = 0.023; 23% vs. 74%, P < 0.0001), reflecting a higher false-positive (FP) rate in subjects receiving CHOP-R (77% vs. 26%, P < 0.001). In the latter group, FP-rate remained persistently high up to 3 years post-therapy. Multivariate analysis confirmed rituximab to be the most significant predictor for FP-PET. In conclusion, routine surveillance FDG-PET is not recommended in DLBCL treated with rituximab; strict criteria identifying patients in whom FU-PET is beneficial are required.

Allogeneic stem cell transplantation for patients with chronic myeloid leukemia: risk stratified approach with a long-term follow-up.

The use of allogeneic stem cell transplantation (SCT) for chronic myeloid leukemia (CML) was almost abandoned in recent years for very effective targeted therapy with tyrosine kinase inhibitors (TKIs). However, approximately one third of patients still need another treatment including SCT. 38 consecutive CML patients were treated (most in preimatinib era) with allogeneic SCT, using partial T cell depletion (TCD) and preemptive donor lymphocyte infusion (DLI), without post-transplant graft-versus-host disease (GvHD) prophylaxis. Conditioning included busulfan, cyclophosphamide, antithymocytic globulin, and fludarabine followed by donor stem cell transfusion. With a median follow up of 90.5 months (1-134), 32 patients are alive. 97% engrafted. 5-year leukemia free survival (LFS) and overall survival (OS) were 78.95% and 84.2%, respectively. All patients are in major molecular remission and 78% in complete molecular remission. Transplant-related mortality (TRM) was 13%. Twenty-four patients received DLI for residual disease. Acute GvHD, mostly Grades I-II, occurred in 18% of patients post-transplant and in 24% of patients receiving DLI. In conclusion, the risk-adapted approach using only partial TCD and preemptive escalated dose of DLI precluded the need for immunosuppressive medications and reduced the risk of significant GvHD without compromising engraftment and long-term disease control. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc.

The increased risk for pneumocystis pneumonia in patients receiving rituximab-CHOP-14 can be prevented by the administration of trimethoprim/sulfamethoxazole: a single-center experience.

Recent studies suggest an increased risk for Pneumocystis jirovecii pneumonia (PJP) in adults receiving short-interval rituximab-CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) therapy for diffuse large cell B cell lymphoma (DLBCL). This retrospective study evaluates precise PJP incidence and the efficacy of anti-PJP prophylaxis in DLBCL. Patients with DLBCL, aged ≥18 years and treated between December 2004 and December 2010, were included. Details of treatment-related respiratory infections, focusing on PJP incidence, risk factors and prophylaxis, were assessed. A total of 132 patients were analyzed; 47 were treated with rituximab-CHOP therapy every 21 days (R-CHOP-21) and 85 were treated every 14 days (R-CHOP-14). The incidence of treatment-related respiratory infections was higher in patients receiving R-CHOP-14. PJP was diagnosed in 5 patients: 4 in the R-CHOP-14 (6.6%) and 1 in the R-CHOP-21 cohort (2.6%), using triplex polymerase chain reaction (PCR) for PJ in bronchoalveolar fluid. None of the patients receiving P.jirovecii prophylaxis (n = 33) developed PJP, compared with 6.6% of those treated with R-CHOP-14 without such prophylaxis. An older age and R-CHOP administered every 14 rather than every 21 days increased the PJP risk. Trimethoprim/sulfamethoxazole prophylaxis is found to be highly efficient in preventing this life-threatening complication and, therefore, should be recommended for patients receiving the R-CHOP-14 regimen.