Prognostic Risk Classification for Biochemical Relapse-Free Survival in Oligometastatic Recurrent Prostate Cancer Determined by Choline PET.

BACKGROUND: Choline positron emission tomography/computed tomography (PET/CT) is a new imaging technique for the detection of oligometastatic (OM) prostate cancer. The aim of this study was to evaluate the outcomes after initial OM diagnoses; treatment, particularly metastasis-directed therapy (MDT); and determine risk groups. PATIENTS AND METHODS: This multi-center, retrospective study included patients with hormone-sensitive biological relapse after local treatment with curative intent and with fewer than six choline PET/CT metastases. The primary endpoint was biochemical relapse-free survival (bRFS). Risk groups were based on prostate-specific antigen (PSA) ≥ 0.8 ng/mL and metastatic sites at OM cancer diagnosis. RESULTS: Between October 2012 and December 2016, 177 patients were included, with a median follow-up of 49.02 months. The median bRFS was 39.74 months. In multivariate analyses, bone metastases and PSA ≥ 0.8 ng/mL were associated with worse bRFS. Four risk groups (I to IV; hazard ratio [HR], 5.92; 95% confidence interval [CI], 1.32-26.61) were observed, with median bRFS not reached for group I (PSA < 0.8 ng/mL; node metastasis [M1a]), a 40.00-month bRFS for group II (PSA ≥ 0.8 ng/mL; M1a), 29.97-month bRFS for group III (bone metastasis [M1b], whatever the PSA level); and 22.70-month bRFS for group IV (PSA > 0.8 ng/mL and visceral metastasis [M1c]). MDT plus androgen deprivation therapy (ADT) improved bRFS over MDT alone (48.36 vs. 34.16 months; HR, 2.12; 95% CI, 1.38-3.26), particularly for group II (HR, 2.09; 95% CI, 1.09-4.00), and reached a limit of significance for group III (HR, ;3.79 95% CI, 0.88- 16.38). CONCLUSION: Prognostic group classifications were confirmed: PSA < 0.8 ng/mL and M1a showed a better outcome than patients with M1c and PSA ≥ 0.8 ng/mL. These results could facilitate patient selection for prospective clinical trials in OM prostate cancer.

Comparison of expressed human and mouse sodium/iodide symporters reveals differences in transport properties and subcellular localization.

The active transport of iodide from the bloodstream into thyroid follicular cells is mediated by the Na+/I- symporter (NIS). We studied mouse NIS (mNIS) and found that it catalyzes iodide transport into transfected cells more efficiently than human NIS (hNIS). To further characterize this difference, we compared (125)I uptake in the transiently transfected human embryonic kidney (HEK) 293 cells. We found that the V(max) for mNIS was four times higher than that for hNIS, and that the iodide transport constant (K(m)) was 2.5-fold lower for hNIS than mNIS. We also performed immunocytolocalization studies and observed that the subcellular distribution of the two orthologs differed. While the mouse protein was predominantly found at the plasma membrane, its human ortholog was intracellular in approximately 40% of the expressing cells. Using cell surface protein-labeling assays, we found that the plasma membrane localization frequency of the mouse protein was only 2.5-fold higher than that of the human protein, and therefore cannot alone account for the difference in the obtained V(max) values. We reasoned that the observed difference could also be caused by a higher turnover number for iodide transport in the mouse protein. We then expressed and analyzed chimeric proteins. The data obtained with these constructs suggest that the iodide recognition site could be located in the region extending from the N-terminus to transmembrane domain 8, and that the region between transmembrane domain 5 and the C-terminus could play a role in the subcellular localization of the protein.

[Unexpected focal bowel 18-FDG uptake sites: should they be systematically investigated?]. / Hyperfixations intestinales focales de découverte fortuite sur la TEP au 18-FDG : faut-il proposer une exploration de façon systématique ?

The purpose of the present study was to retrospectively evaluate the nature and significance of unexpected focal 18-FDG uptake localized by PET/CT within the intestinal tract. Methods. The data of 4,033 PET/CT were retrospectively reviewed. One hundred and eighty PET/CT showed unexpected focal uptakes (patients with known intestinal neoplasia were excluded). Among them, 42 patients corresponding to 47 focal uptake sites were investigated by endoscopy or surgery. Results. Height endoscopy results were negative (17%). We found 25 adenomatous polyps (53.2%), 10 neoplasms (21.3%) and 4 inflammatory lesions (8.5%). 18-FDG uptake values were not statistically different between the 4 groups. Conclusion. Eighty-three percent of unexpected intestinal foci of hypermetabolism are either inflammatory, malignant or premalignant lesions. These results justify systematic investigation of these lesions.

Radioimmunotherapy in relapsed follicular lymphoma previously treated by autologous bone marrow transplant: a report of eight new cases and literature review.

Multicenter, retrospective study of standard-dose RIT in eight heavily pre-treated patients with CD20-positive follicular lymphoma who had relapsed after previous autologous bone marrow transplantation (ABMT). Patients underwent nine courses of (90)Y-ibritumomab tiuxetan (0.3 or 0.4 mCi/kg body weight). Responses included five CR, two PR, one SD and one PD. Median DFS was 12 months with median follow-up of 17 months and 1-year OS was 83% (7/8 patients). Grade 4 thrombocytopenia occurred in 7/9 treatments, with no episodes of bleeding, and only two patients received a platelet transfusion. One patient, who had 20% bone marrow involvement at the time of relapse diagnosis, presented with Grade 4 thrombocytopenia and Grade 4 neutropenia and died of septic shock 6 months after RIT. One other case of Grade 4 neutropenia, without a serious infectious syndrome, was observed. Standard-dose RIT seems feasible and potentially effective after ABMT in correctly selected patients with follicular lymphoma.