Predictive value of initial involvement and early response assessment using positron‑emission tomography with 18F‑FLT in patients with non‑Hodgkin lymphoma

• Main Authors: Yu. N. Likar, M. M. Dubrovin
• Format: Article
• Language: Russian
• Published: ABV-press 2014-07-01
• Series: Onkogematologiâ
• Subjects: PET; 18F‑FDG; 18F‑FLT; diffuse large B‑cell lymphoma
• Online Access: http://oncohematology.abvpress.ru/index.php/ongm/article/view/51

<p>The monitoring of treatment efficacy in patients with diffuse large B‑cell lymphoma (DLBCL) is generally performed by common computed tomography (CT). However, CT cannot distinguish between a real and residual tissue mass and in addition cannot be very useful in assessment of early response. 18F‑FDG Positron‑emission tomography (PET) has high prognostic implications at treatment completion but is limited as an early predictor. We present the results of a retrospective study where we have evaluated predictive value of initial and interim‑PET<br />(I‑PET) with 18F‑FLT on clinical outcome.</p><p><br /><strong>Methods</strong>. 39 patients were evaluated retrospectively with 18F‑FLT PET before treatment and interim 18F‑FLT PET after 1 cycles of chemotherapy. PET was performed 40−60 minutes after injection of 270−340 MBq of 18F‑FLT. Maximum standardized uptake values (SUVmax ) were calculated on a lesion. Response was assessed according to protocol during and in the end of therapy.</p><p><br /><strong>Results.</strong> All lymphoma lesions identified by a reference method (18F‑FDG PET/CT or CT) showed increased focal tracer uptake of 18F‑FLT. Initial mean SUVmax was significantly higher in patients who showed progressive disease and partial response (SUVmax = 9.5 ± 3.2) than in<br />patients who achieved complete response (SUVmax = 6.3 ± 1.6) (p = 0.018). PFS for positive and negative patients after interim 18F‑FLT PET was 85.1 % and 35.7 %, respectively (р &lt; 0.05).</p><p><br /><strong>Conclusion.</strong> High initial 18F‑FLT uptake is a negative treatment response predictor in patients with DLBCL. Positive I‑PET with 18F‑FLT is a negative PFS predictor compare to patients with negative I‑PET.</p>