Loading
5 slides generated from the cancer page, with a quiz from the open benchmark and speaker notes that cite the sources. Arrow keys move between slides; Print gives one slide per page.
Splenic marginal zone lymphoma is a slow-growing lymphoma that grows in the spleen and bone marrow, causing a very large spleen and a raised lymphocyte count but rarely swollen lymph nodes. Many people need no treatment for years; when they do, rituximab has largely replaced removal of the spleen, and hepatitis C should be treated first where it is present.
WHO-HAEM5 keeps splenic marginal zone lymphoma as the splenic member of the marginal zone lymphoma family, defined by massive splenomegaly, moderate lymphocytosis with or without villous lymphocytes, marrow involvement, rare peripheral lymphadenopathy and an indolent course; with no randomised trials there is no formal standard of care, and splenectomy, done for many years, is no longer encouraged first-line because rituximab is as effective with less toxicity (Alaggio 2022; Rev Bras Hematol Hemoter 2017). Its genome carries recurrent NOTCH2, KLF2 and TP53 mutations, with TNFAIP3, KMT2D and TRAF3 also recurrent across 475 cases, though exome studies agree poorly with one another (Scientific Reports 2019). An association with hepatitis C virus is recognised in the ESMO guideline, which recommends antiviral therapy as first treatment in infected patients (Zucca 2020).
How it differs from its parent: it is diagnosed from blood, marrow and spleen rather than a tissue biopsy of an organ or node; it carries the NOTCH2 and KLF2 lesions the other marginal zone lymphomas mostly lack; and its differential diagnosis includes hairy cell leukaemia and the new WHO-HAEM5 category of splenic B-cell lymphoma/leukaemia with prominent nucleoli.
| Setting | Approach | Guideline |
|---|---|---|
| Asymptomatic | Watch and wait; antiviral therapy first if hepatitis C is present. | not mapped |
| Symptomatic | Rituximab alone or with chemotherapy; splenectomy for selected patients; BTK inhibitors or lenalidomide-rituximab later. | not mapped |
| Splenic marginal zone lymphoma: hepatitis C first, then rituximab, then splenectomy | An indolent disease of the spleen, marrow and blood. A patient with no symptoms, no cytopenias and a spleen that is not troublesome is watched, sometimes for years. When treatment is needed, the order is: test and treat hepatitis C if present, because direct-acting antivirals alone produce lymphoma remission in a proportion of hepatitis C-associated cases and that is a reason to check before giving any chemotherapy. Then rituximab alone, weekly for four to eight doses, which corrects cytopenias and shrinks the spleen in the large majority and has displaced splenectomy as first treatment. Chemoimmunotherapy with bendamustine and rituximab is used for disease that does not respond or that transforms. Splenectomy is now reserved for patients who cannot have rituximab, whose disease is confined to the spleen and who need a diagnosis, or who have refractory painful splenomegaly. It requires pneumococcal, Haemophilus influenzae type b and meningococcal vaccination at least two weeks beforehand where possible, and lifelong penicillin prophylaxis afterwards. Zanubrutinib has activity in relapsed disease across marginal zone subtypes. | not mapped |