Faculty Bibliography

The role of [¹⁸F]fluorodeoxyglucose (FDG) positron-emission tomography (PET) in mucosa-associated lymphoid tissue (MALT) of marginal zone lymphoma remains poorly defined. We correlated initial PET with pathology, clinical factors, and outcome. From January 2001 to July 2012, 173 MALT lymphoma patients with a biopsied lesion identified on PET within 90 days of tissue biopsy were analyzed. PET positivity and intensity of FDG uptake were correlated with clinical factors and patient outcome. Among 173 accrued cases, biopsied site was PET avid in 123 patients (71%); median standardized uptake value (SUV) was 6.0 (range: 0.7-28.0), and SUV >10.0 in 20 patients (16%). PET avidity varied by organ sites. PET positivity correlated with higher International Prognostic Index, but not with 5-year overall survival (OS; 96% vs 88%, PET negative vs positive, P = .229) or 5-year progression-free survival (67% vs 56%, P = .493). SUV was an independent prognostic factor of OS, and an increased SUV was associated with a decreasing 5-year OS. Patients who presented with SUV ≥10 had a higher rate of subsequent large cell transformation (20% vs 5%, P = .035) and inferior OS (78% vs 92%, P = .008). The exact role of FDG PET in the management of MALT lymphoma, beyond initial staging, remains to be defined.

PURPOSE:Approximately one third of patients with cancer require palliative radiation therapy (PRT), yet no guidelines exist for optimal patient selection. We have observed that many patients who begin PRT do not complete their prescribed treatment. Our study sought to identify factors associated with discontinuation of PRT, assess for a relationship with survival, and inform patient selection. METHODS:We performed an institutional review board-approved retrospective analysis of patients with cancer treated in a multicenter radiation oncology department in 2014. Of 297 patients who began PRT, 60 discontinued and 237 completed treatment. Primary end points included discontinuation and overall survival. RESULTS:Patient factors were analyzed for association with discontinuation of PRT and overall survival, respectively, using logistic regression and Cox proportional regression models. Factors associated with discontinuation were low Karnofsky performance status (KPS) score, high number of fractions prescribed, and treatment site other than bone metastasis. The odds of discontinuing PRT decreased by approximately 52% for every 10-point increase in KPS score (odds ratio, 0.48; 95% CI, 0.36 to 0.63; P < .001). Factors associated with shorter survival included discontinuation of PRT, low KPS score, community practice location, multiple comorbidities, and treatment of brain metastases. Patients who discontinued treatment were more likely to die than patients who completed treatment, independent of other factors (hazard ratio, 3.67; 95% CI, 2.41 to 5.61; P < .001). CONCLUSION:Patients with low KPS scores, long treatment courses, and those treated to sites other than bone metastasis were significantly more likely to discontinue treatment. Discontinuation was predictive for poor survival. Pretreatment evaluation of KPS, comorbidities, and brain metastases can help guide appropriate patient selection for PRT.