Adult T-cell leukaemia/lymphoma (ATLL) is a unique lymphoproliferative disorder [1–4] that develops only in individuals who are chronic carriers of the retrovirus, human T-cell lymphotropic virus I (HTLV-I) [5, 6]. The interval between acquiring the virus and developing the lymphoma is usually 30–60 years with the life-time risk of developing ATLL being of the order of 2% for women and 6% for men. Since only a minority of HTLV-I carriers develop ATLL it is clear that there must be co-factors that contribute to development of the condition; the nature of these remains unknown although Strongyloides stercoralis infection has been suspected. HTLV-I can also cause polymyositis, arthritis, uveitis and HTLV-I-associated myelopathy (also known as tropical spastic paraparesis). In addition it leads to immunosuppression, which is responsible for an increased incidence of infective dermatitis, Pneumocystis jiroveci (previously known as Pneumocystis carinii) pneumonia, Strongyloides stercoralis hyperinfection and virus-related tumours (e.g. carcinoma of the cervix, Kaposi's sarcoma and hepatoma related to hepatitis viruses). Because of the distribution of HTLV-I, ATLL is distributed unevenly throughout the world. The best-recognized endemic areas are Japan (particularly the island of Kyushu) and the Caribbean but, in fact, there are likely to be more cases in South America and Africa, where carriers of the virus are even more numerous. Endemic cases have also been observed in Eastern Europe. Cases are found in Europe and North America, among migrants from endemic areas.
About 10-20% of individuals who develop ATLL present with lymphoma without involvement of the peripheral blood or bone marrow. The other 80-90% have leukaemic manifestations. There is usually lymphadenopathy (Figure 16.1) and there may be hepatomegaly, splenomegaly and skin infiltration (papules, nodules and plaques) (Figure 16.2). A minority of patients have pleural effusions, ascites or infiltration of lung, liver, gastrointestinal tract, leptomeninges or brain (Figure 16.3). Hypercalcaemia is a common clinical feature, either at presentation or during disease progression; it may be associated with lytic bone lesions and is the result of stimulation of osteoclasts by cytokines secreted by the neoplastic cells. Hypercalcaemia can lead to dehydration and renal impairment. The clinical course is usually acute but smouldering and chronic forms of the disease are recognized.
Clinical photograph showing lymphadenopathy and skin infiltration.
Clinical photograph showing skin infiltration.
CT scan of the brain showing cerebral infiltration.
Haematological and pathological features
Leukaemic cells are distinctive, being medium sized pleomorphic cells with irregular nuclei, which may be convoluted or deeply lobulated. Nucleoli are often present and some have a blastic chromatin pattern. The ...