Limited Usefulness of 18F-FDG PET/CT in Predicting Tumor Regression After Preoperative Chemotherapy for Noncardia Gastric Cancer: The Italian Research Group for Gastric Cancer (GIRCG) Experience.

BACKGROUND: The present study aimed to better define the usefulness of F-FDG PET/CT in predicting pathological tumor response (PTR) and survival in patients with noncardia gastric cancer treated with preoperative chemotherapy. METHODS: Seventy-one patients were recruited in 6 Italian centers. The SUV of F-FDG PET/CT was measured at baseline and after treatment, and the difference (dSUV) was computed. The association between PET indexes and PTR, assessed by the Becker score, was evaluated by nonparametric regression. The discriminant power of PET indexes with respect to the absence of PTR (Becker 2/3) was studied by receiver operating characteristic (ROC) curve and synthesized by the area under the curve (ROC-AUC). RESULTS: dSUV allowed to partially discriminate between absence/presence of PTR, when expressed as either absolute value (ROC-AUC, 0.73; 95% confidence interval, 0.59-0.87) or percentage (ROC-AUC, 0.74; 95% confidence interval, 0.59-0.89). However, only extreme values of percent dSUV were really informative. All 7 patients whose F-FDG uptake had increased despite preoperative treatment showed no tumor regression at pathologic examination. Seven of the 10 patients whose metabolic response had been 70% or greater had complete or nearly complete pathologic tumor regression (Becker score 1a or 1b). The metabolic response of the remaining 54 patients, which ranged between 0% and 70%, did not permit to reliably forecast pathologic tumor regression. Survival significantly decreased with increasing Becker score but was unaffected by metabolic response. CONCLUSIONS: The present study suggests that F-FDG PET/CT has limited usefulness in predicting cancer regression. The lack of metabolic response in serial measurements indicates the probable ineffectiveness of preoperative treatment.

Long-term remission in a case of plasmablastic lymphoma treated with COMP (cyclophosphamide, liposomal doxorubicin, vincristine, prednisone) and bortezomib.

Plasmablastic lymphoma (PBL) is a rare subtype of non-Hodgkin lymphomas (NHL) strongly associated with HIV infection, even if cases in other immunosuppressed patients such as solid organ transplant recipients and in immunocompetent individuals have been increasingly reported. Current treatment strategy for HIV-negative patients is similar to DLBCL as first-line treatment, but durable remissions are seldom observed. Anthracycline-containing regimens could be too toxic for elderly patients and/or with cardiac failure, because a non-pegylated liposomal doxorubicin (NLD) could be used in this field. Bortezomib, a proteasome inhibitor currently approved for patients with multiple myeloma and relapsed mantle-cell lymphoma, has recently showed clinical activity in PBL patients. Herein, we report a rapid and long-term remission of a PBL patient with cardiac failure and that had previously received a double kidney transplant, treated front-line with COMP (with a NLD substituted for doxorubicin) followed by subcutaneous bortezomib consolidation. We suggest first-line treatment outcome is determinant for PBL patients. Bortezomib has a promising role and should be incorporated in future clinical trials and NLD could represent a suitable option for patients with cardiac failure or high cardiovascular risk.

Single Agent Lenalidomide Activity in Multiple Myeloma Relapse Evidenced Uniquely by CT/PET.

A 71 year old female with multiple myeloma presented with back pain seven year after autologous stem cell transplant. Skeletal bone survey and magnetic resonance imaging did not show a relapse that was evidenced by CT/PET. Lenalidomide as single agent induced a complete disappearance of the lesions 6 months later and confirmed after one year at CT/PET.