P119 | ULTRASOUND ASSESSMENT OF CHRONIC LYMPHOCYTIC PATIENTS DURING BTK TREATMENT: COMPARISON OF DIMENSIONAL RESPONSE VS OVERALL ULTRASOUND ASSESSMENT IN GENERAL PRACTICE. PRELIMINARY RESULTS OF A PROSPECTIVE STUDY

Background. IWCC and ESMO guidelines suggest abdominal ultrasound (AUS) and superficial lymphnodes (SLN) palpation to assess patients with chronic lymphocytic leukemia (CLL) in general practice. Computed tomography (CT) is generally not indicated out of a clinical trial. The CLL expert Tuscany panel included SLN ultrasound (SLUS) in general practice. SLUS assessment in CLL patients has been previously published and CLL diseased SLN have been described (1). Mat & methods: we collected a total of N= 600 US examinations. Prospectively we enrolled N=60 patients treated with BTK inhibitors: Ibrutinib (I) N=25, Acalabrutinib (A) N=25, and Zanubrutinib (Z) N=25. Patients US follow up was a median of 18months (range 9 to 24 months). Patients were assessed with US every three months. We compared response to treatment based on US SLN dimensions vs and overall SLUS which considers: SLN dimensions, cortex, hilum as previously described (1). In this study we focused on SL response assessment. Results: best SLN response was obtained at a median of 9, 9, and 6 months for patients treated with I, A, and Z, respectively. Overall, we assessed an of N=800 SLN. SLN response based on SLN dimensions were defined N=24 (40%) CR, N=15 (25%) PR, N=16 (27%) SD, and P N=5 PD (8%). SLN response US-based defined CR N= 30(50%) PR N=24(48%), SD N=2(3%), and PD N=4(7%). There was a statically significant difference in patients reaching a SD and a strong trend for PR defined by dimensions vs US assessment (p=0.0002, and p=0.009, respectively). No statistically significant difference was found in patients in CR or PD (p= 0.272, and p= 0.835, respectively). Conclusions: SLN US analysis of all LN characteristics allows to better define CLL patients’ response to BTK inhibitors in respect to only SLN dimensions assessment with a potential impact on treatment decisions. These preliminary results suggest a rule of SLUS to help define response to BTK inhibitors. References 1) 10.3390/jcm11113206