Faculty Bibliography

We report a comprehensive study of a case of aggressive natural killer cell lymphoma/leukemia, which is characterized by young male predominance, rapidly progressive clinical course, and presence of lymphadenopathy, hepatosplenomegaly, and bone marrow involvement. The leukemic phase is frequently preceded by pancytopenia. The diagnostic clues are the detection of cytoplasmic granules in tumor cells on Wright-Giemsa-stained tissue imprints or smears and a selective loss of T-cell antigens. Immunophenotyping is decisive in making the final diagnosis by showing positive natural killer cell markers (CD16, CD56, and/or CD57), CD2, CD11c, and Ia, but negative CD3, T-cell receptor heterodimers, terminal deoxynucleotidyl transferase, and B-cell markers. Genotyping always shows germline configuration in both immunoglobulin and T-cell receptor genes. The unique feature in this case is its presentation as a testicular lymphoma, which has not been previously reported. Polymerase chain reaction was performed in this case but failed to detect human T-cell leukemia virus type I/II provirus. It is important to recognize this new entity as it is a highly aggressive disease with a rapidly progressive clinical course and fails to respond to any chemotherapeutic regimen available

Six cases of large granular T-cell lymphoproliferative disorder with a selected immunophenotype (CD3+, CD4-, CD8+, CD16+) were studied to characterize a homogeneous group of patients. It was found that most of these patients did not exhibit the clinical features frequently described in large granular T-cell lymphoproliferative disorder--recurrent infection, rheumatoid arthritis, and splenomegaly. The laboratory tests usually positive in large granular T-cell lymphoproliferative disorder, including rheumatoid factor and anti-nuclear antibodies, also were frequently negative. The pathognomonic features were found to be neutropenia and large granular lymphocytosis with positive killer cell markers. All six cases showed T-cell receptor gene rearrangement that indicated a monoclonal proliferation of lymphoid cells, which were natural killer-like T cells by immunophenotyping. B cells were essentially absent in all cases. It should be emphasized that bone marrow aspirates are as informative as peripheral blood samples for the diagnosis of large granular T-cell lymphoproliferative disorder; indeed, phenotypes of blood and marrow in one case were identical in terms of percentages of markers. In this selected group of patients, the clinical courses were indolent with uncomplicated outcomes. In three patients, chemotherapy did not induce an obvious clinical response, but all patients' conditions remained stable with only supportive care.

The ageing of the population has resulted in a greater emphasis on cancer treatment effects in elderly patients. This population has often had arbitrary dose modification of chemotherapy owing to fear of excessive side-effects. A review was undertaken to evaluate cisplatin toxicity in patients of 70 years of age or older. Thirty-four patients were evaluated. Their mean age was 72.8 years and 85.3% were women. Fourteen of 34 (41%) patients completed the planned therapy. Treatment was terminated because of disease progression (35%), renal toxicity (9%) and non-renal toxicity (15%). Our conclusion is that cisplatin can safely be administered to elderly patients. Arbitrary dose modification or elimination of cisplatin from a treatment programme on the grounds of patient age alone is not justified.

Large granular T-cell lymphoproliferative disorder (LGTLD) is a heterogeneous disorder covering a broad spectrum of diseases and requiring further subdivision. Most reported cases emphasized its suppressor phenotype (T gamma cell or CD8+), but we encountered two cases of CD3+, CD4-, CD8- LGTLD. Both cases had a benign clinical course and required no chemotherapy despite persistent lymphocytosis. This unique phenotype has been reported in a few cases of acute lymphoblastic leukemia expressing the T-cell receptor (TcR) gamma chain gene and is considered the counterpart of thymocytes at the intermediate stage between early precursors and mature thymocytes. Our case 1 provides further evidence that the CD3+, CD4-, CD8- phenotype, indeed, expresses the TcR gamma chain gene. However, the negative reaction to terminal deoxynucleotidyl transferase in our case 1 indicates that this phenotype represents proliferation of peripheral T-cells, in which about 2% bear the CD3+, CD4-, CD8- phenotype in the normal population. The selective use of CD3, CD4, CD8, HNK-1 monoclonal antibodies and of cytochemical stains (acid phosphatase and alpha-naphthyl butyrate esterase) for characterization of this disorder is discussed.