Clonal heterogeneity of polymorphic B-cell lymphoproliferative disease, EBV-positive, iatrogenic/immune senescence: implications on pathogenesis and treatment

BACKGROUND

Epstein Barr virus positive (EBV+) immunodeficiency-associated lymphoproliferative disorders (IA-LPD) are heterogeneous diseases with variable treatment strategies that are not well-defined.

CASE PRESENTATION

A 68-year-old woman with systemic lupus erythematosus developed EBV+ B-cell polymorphic lymphoproliferative disease (LPD). Positron emission tomography computed tomography (PET/CT) showed a large nasopharyngeal mass, multiple pulmonary lesions, splenomegaly and disseminated lymphadenopathy. Plasma EBV DNA was grossly elevated to 1.5 × 10⁴ IU/mL. There were three paraproteins. Treatment with O-CHOP (obinutuzumab, cyclophosphamide, adriamycin, vincristine, prednisolone) led to undetectable plasma EBV DNA, suggesting eradiation of the EBV-positive malignant clone. However, radiologic abnormalities were still present on PET/CT, and paraprotein persisted. A nasopharyngeal re-biopsy showed infiltration with EBV-negative plasma cells. On treatment with lenalidomide, she finally achieved complete metabolic response. Molecular analysis showed that the EBV+ B-cell LPD and the EBV- plasma cell lesion exhibited identical immunoglobulin gene rearrangements. Next generation sequencing revealed that the EBV+ B-LPD showed mutation in only one gene (TP53), a profile typical of EBV-driven lymphoid neoplasms. However, the EBV- plasma cell lesion showed mutations in five genes (TP53, SF3B1, STAT5B, CD79B and CRKL), suggesting that these mutations instead of EBV infection were the oncogenic driver.

CONCLUSION

The presence of both EBV+ and EBV- lesions, which showed different mutational profiles, indicated clonal heterogeneity that might be of biologic and therapeutic significance.

Spectrum of B-cell neoplasms associated with immunoglobulin G4-related disease

Immunoglobulin G4-related disease (IgG4-RD) has rarely been associated with lymphoid neoplasms, the spectrum of which remains unclear. B-cell lymphoid neoplasms (LN) associated with IgG4-RD diagnosed in a 4-year period were analysed. There were five men and three women at a median age of 76.5 (52-90) years; three with synchronous IgG4-RD and LN; three with IgG4-RD preceding LN by 2, 3, and 22 years; and two with LN preceding IgG4-RD by 2.5 and 7 years. All patients presented with disseminated lymphadenopathy. Monoclonal gammopathy of undetermined significance (MGUS)/smouldering multiple myeloma (SMM) was found in three patients, all with an IgGκ paraprotein. Levels of IgGκ and IgG4 correlated. Diffuse large B-cell lymphoma (DLBCL) was found in three patients, with one case showing co-existing lymphoma and IgG4-RD in the same lymph node biopsy. The remaining two cases were marginal zone lymphoma (MZL) developing in a lacrimal gland previously involved by IgG4-RD; and nodular lymphocyte predominant Hodgkin lymphoma (NLP-HL) diagnosed in a lymph node with concomitant IgG4-RD. Low-dose continuous prednisolone was given for MGUS/SMM, with both monoclonal IgGκ and IgG4 responding. Combination chemotherapy was given for DLBCL, with two patients achieving complete response and one patient dying from refractory lymphoma. The patient with MZL refused treatment, whereas the case of NLP-HL responded completely to chemotherapy. Our findings together with previous observations suggest that IgG4-RD has an increased risk of B-cell neoplasms. Patients with IgG4-RD presenting with lymphadenopathy require vigorous investigations to exclude lymphoid neoplasms.