Early therapeutic response assessment by (18)FDG-positron emission tomography during chemotherapy in patients with diffuse large B-cell lymphoma: isolated residual positivity involving bone is not usually a predictor of subsequent treatment failure.

Residual 2-fluoro-2-deoxyglucose (FDG) - positron emission tomography (PET) positivity during treatment of patients with diffuse large B-cell lymphoma (DLBLC) prospectively identifies a subgroup at high likelihood of subsequent treatment failure. A single institution clinical audit of FDG-PET performance for this indication was undertaken for patients with DLBCL treated with anthracycline-based chemotherapy +/- radiotherapy. Of 45 eligible patients, 14 (31%) were PET-positive after a median of three chemotherapy cycles (range 1 - 5), of which 10 (71%) progressed at a median of 6.5 months. An interim positive PET was a statistically significant adverse prognostic factor for treatment failure (P < 0.0001, log-rank analysis) with a hazard ratio for a positive interim-treatment PET of 9 (95% confidence interval = 4 - 55) and positive predictive value of 71% and negative predictive value of 90%. Notably, four patients with low-grade FDG-avidity limited to sites previously involved by biopsy-proven osseous lymphoma, remain progression-free (median follow-up 62 months). Low-grade FDG-avidity on interim restaging at sites of bone involvement by DLBCL at diagnosis, appears to be less predictive of disease progression than residual nodal or extra-nodal soft tissue abnormality by PET.

Cytomegalovirus DNAemia and disease: incidence, natural history and management in settings other than allogeneic stem cell transplantation.

BACKGROUND AND OBJECTIVES: Despite increasing intensity and profound immunosuppression associated with newer therapies for hematologic malignancies, little information exists regarding cytomegalovirus (CMV) reactivation in settings other than allogeneic stem cell transplantation (SCT). DESIGN AND METHODS: We reviewed the epidemiology of CMV disease in patients who were CMV polymerase chain reaction (PCR) positive during treatment for hematologic malignancies without allogeneic SCT from June 1999 to June 2004. RESULTS: Thirty-six patients with CMV reactivation were identified. Of these, 92% were undergoing investigation for fever. Fifteen patients with CMV DNAemia were treated with ganciclovir without CMV disease developing. Notably, 20 patients with untreated CMV DNAemia did not develop CMV disease during a median follow-up of 3.5 (1-19) months. The highest rates of reactivation were observed with HyperCVAD (7.8%) and alemtuzumab (50%). INTERPRETATION AND CONCLUSIONS: We recommend that screening for CMV DNAemia be instituted and pre-emptive therapy contemplated for asymptomatic CMV reactivation only in patients receiving alemtuzumab therapy, but not routinely for other patients outside the allogeneic SCT setting. Indeed for such patients, detection of isolated CMV DNAemia does not imply the need for immediate therapy and future studies are needed to validate PCR detection of CMV DNA and CMV DNA titers as predictors for CMV disease.