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INTRODUCTION: The aim of this study is to investigate the relationship between the radiation dose to pelvic and para-aortic lymph nodes, nodal response, and clinical outcomes in a resource-poor setting based on computed tomography (CT) nodal size alone. MATERIALS AND METHODS: This retrospective study from 2009 to 2015 included 46 cervical cancer patients with 133 metastatic pelvic and para-aortic lymph nodes definitively treated with chemoradiation and brachytherapy in a public hospital with limited access to positron emission tomography (PET) scans. Hence, short axis of the lymph node on CT scan was used as a measure of metastatic nodal disease, before and following radiation therapy. Inclusion criteria required the pelvic and para-aortic nodes to have the shortest axis diameter on CT scan of ≥8 mm and ≥10 mm, respectively. Based on PET resolution, a node that decreased to half of its inclusion cutoff size was considered to have a complete response (CR). Relevant clinical outcomes were documented and correlated with nodal features, nodal radiation doses, and treatment characteristics. RESULTS: After controlling for other predictive factors, increased nodal dose was associated with increased probability of CR per study definition (P = 0.005). However, there was no statistically significant association between dose and pelvic/para-aortic, distant and total recurrence (TR), and any recurrence at any location (P = 0.263, 0.785, 1.00, respectively). Patients who had no CR nodes had shorter pelvic/para-aortic recurrence-free survival (PPRFS) and TR-free survival (TRFS) than patients who had at least one CR node (P = 0.027 and 0.046, respectively). Patients with no CR nodes also had shorter PPRFS than patients who had all nodes completely respond (P < 0.05). CONCLUSIONS: Using CT-based measures, we found that increased nodal dose is associated with an increased probability of CR (as defined) and nodal CR is associated with increased PPRFS and TRFS. We were unable to determine the cutoff dose required for a CR.
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We assessed the value of positron emission tomography to predict long-term outcome in patients with diabetes and ischemic left ventricular (LV) dysfunction. Circumferential profiles of nitrogen-13 ammonia (NH3) and fluorine-18 fluorodeoxyglucose uptakes were obtained in 61 patients who had diabetes and ischemic LV dysfunction. Patient profiles were compared with those from a normal database. NH3 and fluorine-18 fluorodeoxyglucose defect sizes and extent of perfusion-metabolism mismatch (percentage of myocardium with fluorine-18 fluorodeoxyglucose uptake minus NH3 uptake >2 SD above the normal difference) were determined. Patients were followed every 6 months. Over a mean follow-up of 4.3 years, cardiac death occurred in 52% of patients who underwent revascularization and 61% of those who underwent medical therapy (p = 0.69). No clinical or imaging variables predicted cardiac death in patients who underwent revascularization. In those who received medical therapy, mismatch in > or =3% of the left ventricle (risk ratio 4.0, p = 0.01) was the only multivariate predictor of cardiac death. Revascularization improved survival of patients who had mismatch of > or =3% at 4 years (p = 0.003) and at 8 years (p = 0.012) of follow-up. Patients who had mismatch > or =3% and ejection fraction <30% had the greatest improvement in survival with revascularization compared with medical therapy (p <0.0001). Revascularization also improved 4-year survival of patients who had NH3 perfusion defects of > or =25% of the left ventricle (p = 0.02). In conclusion, mismatch identifies medically treated patients who have diabetes and LV dysfunction, who are at high risk for cardiac death. Intermediate- and long-term survival of patients who have diabetes and mismatch may be improved with revascularization, and those who have significant mismatch and severe LV dysfunction have the greatest benefit.