Jack Naughton¹, Patrick Hosking^1
1Eastern Health Pathology, Box Hill Hospital, Box Hill, Victoria, Australia 

Transformation of CLL/SLL into a more aggressive lymphoma was first described in 1928 by Maurice Richter, and was subsequently coined Richter transformation. Diffuse large B-cell lymphoma (DLBCL) is the most common histological subtype, with transformation into T-cell lymphoma and Hodgkin lymphoma less commonly described. Approximately 9% of patients with untreated CLL/SLL transform into DLBCL¹, while approximately 0.4% transform into Hodgkin lymphoma². Richter transformation is typically characterized by a marked increase in lymphadenopathy at one or more sites (often abdominal) and worsening of B symptoms³. We present the novel case of an 80 year old female with long standing CLL/SLL who presented with severe AKI and hypertension and was found to have a PET avid caecal lesion. Biopsy of this caecal lesion revealed three concurrent lymphomas, CLL and dual Richter transformation into morphologically distinct DLBCL NOS and high-grade B cell lymphoma NOS (HGBCL NOS). 

References:
1. Rossi D, Cerri M, Capello D, Deambrogi C, Rossi FM, Zucchetto A, De Paoli L, Cresta S, Rasi S, Spina V, Franceschetti S, Lunghi M, Vendramin C, Bomben R, Ramponi A, Monga G, Conconi A, Magnani C, Gattei V, Gaidano G. Biological and clinical risk factors of chronic lymphocytic leukaemia transformation to Richter syndrome. Br J Haematol. 2008 Jun;142(2):202-15. doi: 10.1111/j.1365-2141.2008.07166.x. Epub 2008 May 19. PMID: 18492108. 
2. Tsimberidou AM, O'Brien S, Kantarjian HM, Koller C, Hagemeister FB, Fayad L, Lerner S, Bueso-Ramos CE, Keating MJ. Hodgkin transformation of chronic lymphocytic leukemia: the M. D. Anderson Cancer Center experience. Cancer. 2006 Sep 15;107(6):1294-302. doi: 10.1002/cncr.22121. PMID: 16902984. 
3. Mukkamalla SKR, Taneja A, Malipeddi D, et al. Chronic Lymphocytic Leukemia. [Updated 2023 Mar 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470433/