OBJECTIVE: To evaluate SPECT/CT with radiolabeled somatostatin analogues (RSAs) in systemic granulomatous infections in comparison with gallium-67 (⁶⁷Ga) citrate scintigraphy. MATERIALS AND METHODS: We studied 28 patients with active systemic granulomatous infections, including tuberculosis, paracoccidioidomycosis, pneumocystosis, cryptococcosis, aspergillosis, leishmaniasis, infectious vasculitis, and an unspecified opportunistic infection. Of the 28 patients, 23 had started specific treatment before the study outset. All patients underwent whole-body SPECT/CT imaging: 7 after injection of ^99mTc-EDDA-HYNIC-TOC, and 21 after injection of ¹¹¹In-DTPA-octreotide. All patients also underwent ⁶⁷Ga citrate imaging, except for one patient who died before the ⁶⁷Ga was available. RESULTS: In 20 of the 27 patients who underwent imaging with both tracers, 27 sites of active disease were detected by ⁶⁷Ga citrate imaging and by SPECT/CT with an RSA. Both tracers had negative results in the other 7 patients. RSA uptake was visually lower than ⁶⁷Ga uptake in 11 of the 20 patients with positive images and similar to ⁶⁷Ga uptake in the other 9 patients. The only patient who did not undergo ⁶⁷Ga scintigraphy underwent ^99mTc-EDDA-HYNIC-TOC SPECT/CT-guided biopsy of a lung cavity with focal RSA uptake, which turned to be positive for aspergillosis. CONCLUSION: SPECT/CT with ^99mTc-EDDA-HYNIC-TOC or ¹¹¹In-DTPA-octreotide seems to be a good alternative to ⁶⁷Ga citrate imaging for the evaluation of patients with systemic granulomatous disease.

Keywords: Single photon emission computed tomography; X-ray computed tomography; Octreotide; Gallium-67; Tuberculosis; Paracoccidioidomycosis.

Objective: To determine whether the whole-body tumor burden, as quantified by ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT), is a prognostic indicator in advanced (stage III or IV) non-small cell lung cancer (NSCLC). Materials and Methods: This was a prospective study in which we evaluated ¹⁸F-FDG PET/CT staging parameters to quantify tumor burdens in patients with stage III or IV NSCLC. The following parameters were evaluated for the whole body (including the primary tumor) and for the primary tumor alone, respectively: maximum standardized uptake volume (wbSUV_max and tuSUV_max); metabolic tumor volume (wbMTV and tuMTV); and total lesion glycolysis (wbTLG and tuTLG). To determine whether the ¹⁸F-FDG PET/CT parameters were associated with overall survival (OS) and progression-free survival (PFS), we evaluated the wbSUV_max/tuSUV_max, wbMTV/tuMTV, and wbTLG/tuTLG ratios. Results: ¹⁸F-FDG PET/CT was performed for staging in 52 patients who were followed for a median of 11.0 months (mean, 11.7 months). The estimated median PFS and OS were 9.6 months and 11.6 months, respectively. In the univariate analysis, OS was found to correlate significantly with wbTLG (hazard ratio [HR] = 1.001; 95% confidence interval [95 CI]: 1.000–1.001; p = 0.0361) and with the wbTLG/tuTLG ratio (HR = 1.705; 95% CI: 1.232–2.362; p = 0.0013). In the multivariate analysis, only the wbTLG/tuTLG ratio was independently associated with OS (HR = 1.660; 95% CI: 1.193–2.310; p = 0.0027). Conclusion: The wbTLG/tuTLG ratio is an independent prognostic indicator of OS in advanced-stage NSCLC.

Keywords: Fluorodeoxyglucose F18; Positron-emission tomography/methods; Tomography, X-ray computed/methods; Carcinoma, non-small-cell lung/diagnosis; Tumor burden; Carcinoma, non-small-cell lung/mortality.