Introduction Demographics Causes Clinical features Complications Diagnosis Differential diagnoses Treatment Outcome
Intravascular lymphoma is a rare subtype of large B-cell lymphoma in which lymphoma cells proliferate within the lumen of small blood vessels. It most often presents with central nervous system (CNS) and skin signs. The cutaneous variant of intravascular lymphoma is limited to the skin [1].
Intravascular lymphoma is also known as intravascular large B-cell lymphoma, intravascular lymphomatosis, angiotropic large cell lymphoma, and malignant angioendotheliomatosis. As a diagnosis of intravascular lymphoma can be difficult, it is often only diagnosed on autopsy.
Intravascular lymphoma is rare, and its true incidence is unknown. The most typical age of diagnosis is 50–70 years of age. It occurs equally in both men and women [1–3].
The cutaneous variant of intravascular lymphoma is mostly diagnosed in young adult women [1]. There are Western and Asian forms of the disease.
Intravascular lymphoma is caused by the proliferation of neoplastic lymphoid cells within capillaries and post-capillary venules. These neoplastic cells are usually mature CD20+ B cells (CD20 is an antigen on the surface of some B cells), but there have been rare cases of T-cell or (NK)-cell intravascular lymphoma [2].
The presentation of intravascular lymphoma is varied. Typically, and unlike other forms of lymphoma, there is no tumour mass or detectable circulating lymphoma cells.
Other cutaneous features seen in intravascular lymphoma include:
Lymphoma is found in other organs in about 30% of patients with cutaneous features [1]. The spleen, liver, and bone marrow are less frequently involved.
Intravascular lymphoma soon results in multi-organ dysfunction, due to bone marrow, renal, hepatosplenic (liver and spleen), and CNS involvement. The disease is commonly fatal within a few months of diagnosis.
Intravascular lymphoma is diagnosed by deep skin biopsy of cutaneous lesions or by random biopsies of apparently healthy skin.
Several other disorders may be considered in patients who present with the cutaneous features of intravascular lymphoma. These disorders include:
Other inflammatory or immune reactions of the lymph nodes produce activated lymphocytes in the post-capillary venules without any constitutional symptoms, blood derangement, or organ dysfunction.
Intralymphatic histiocytosis is a reactive condition of macrophages, associated with rheumatoid arthritis. It may present with lesions that are clinically similar to intravascular lymphoma and has an intravascular proliferation of large cells. It can be differentiated from intravascular lymphoma on immunophenotyping, which will demonstrate macrophage-specific markers and the absence of lymphoid markers [7].
There are no published guidelines or evidence from controlled trials for the treatment of intravascular lymphoma.
The general expert consensus is that patients with intravascular lymphoma should be considered to have disseminated disease. The majority of patients are treated with intensive chemotherapy; particularly, a combination of the recombinant anti-CD20 drug rituximab, cyclophosphamide, doxorubicin (hydroxydaunomycin), vincristine (Oncovin®) and systemic steroids, such as prednisone or prednisolone (R-CHOP) [1].
Those with a single cutaneous lesion can be considered for treatment with radiotherapy, with or without chemotherapy.
Clinical follow-up is mandatory to detect disease progression and involvement of other organs [4].
Intravascular lymphoma often has a fatal course due to late diagnosis and advanced disease at the time of diagnosis. Biopsy of the skin lesions enables early diagnosis.
In general, patients with the cutaneous variant of intravascular lymphoma have better outcomes than patients who have involvement of other organs (10% of patients with the cutaneous variant have a fatal outcome versus 85% of patients with other organ involvement). The morphology of the skin lesions does not predict the clinical course or prognosis of the lymphoma; however, multiple cutaneous lesions are associated with a worse outcome than single lesions [1].
