case_images: PMC10651334_01
case_images: Histology and immunophenotype of initial transformation to EBV + DLBCL (A-H) and EBV + cHL (I-P), as well as relapsed EBV + cHL (Q-X). H & E-stained images at 20x (A, I, Q) and 400x (B, J, R) magnification. Immunostains for CD20 (C, K, S), PAX-5 (D, L, T), CD30 (E, M, U), CD15 (F, N, V), and OCT-2 (G, O, W) and in situ hybridization for EBER (H, P, X), all at 200x.
case_images: CRIHEM2023-8833273.001.jpg
case_images: PMC10651334_01_CRIHEM2023-8833273.001.jpg
case_images: fig1
case_images: Part of this diffuse proliferation was composed of sheets of large lymphoid cells with vesicular chromatin and variably prominent nucleoli (Figure 1(A, B)). These cells were positive for CD20 (Figure 1(C)), PAX-5 (Figure 1(D)), CD30 (Figure 1(E)), OCT-2 (Figure 1(G)), and EBER (Figure 1(H)) and negative for CD15 (Figure 1(F)). Sections showed an enlarged lymph node with architectural effacement by an atypical, vaguely nodular, mixed infiltrate composed of moderately numerous Reed-Sternberg (R-S) cells and variants with background small lymphocytes and eosinophils (Figure 1(Q, R)). The lymphoma cells were positive for PAX-5 (weak; Figure 1(T)), CD30 (Figure 1(U)), CD15 (Figure 1(V)), MUM1, BCL-6 (weak), BCL-2, and EBER (Figure 1(X)) and essentially negative for CD19, CD20 (Figure 1(S)), BOB1, CD45/LCA, OCT-2 (Figure 1(W)), CD3, and CD10. In addition to regions demonstrating monomorphic DLBCL, we identified a small portion of transformed lymphoma with distinct morphology, background cellularity, and immunophenotype (Figure 1(I, J)). The lymphoma cells were negative for CD20 (Figure 1(K)), OCT-2 (Figure 1(O)), BOB1, and CD79a and positive for PAX-5 (weak; Figure 1(L)), CD30 (Figure 1(M)), CD15 (Figure 1(N)), MUM1, and EBER (Figure 1(P)).
case_images: Representative PET reconstructions showing partial response after 6 cycles of R-CHOP (a), disease persistence following second line therapy (b), and complete metabolic response after brentuximab-nivolumab (c).
case_images: CRIHEM2023-8833273.002.jpg
case_images: PMC10651334_01_CRIHEM2023-8833273.002.jpg
case_images: fig2
case_images: Interval PET scans revealed partial metabolic response after 2 cycles, mixed response with possible radiologic progression in the right iliac after 4 cycles, and disease progression after 6 cycles (Figure 2(a)). By PET, the patient showed a mild improvement after 4 cycles and disease persistence after 5 cycles (Figure 2(b)). In light of the new diagnosis of EBV + cHL and the fact that:despite its occult nature on previous biopsy:this disease component proved refractory to treatment with anthracycline-based therapy, the patient was started on brentuximab vedotin plus nivolumab with a complete metabolic response after 2 cycles seen on the PET scan (Figure 2(c)).