Nnenna Osuji

Long-term follow-up of 233 patients with hairy cell leukaemia, treated initially with pentostatin or cladribine, at a median of 16 years from diagnosis

Hairy cell leukaemia (HCL) was first described 50 years ago. Median survival was then 4 years. The purine analogues, introduced in the 1980s, transformed this prognosis. We reviewed data retrospectively from 233 patients, treated with pentostatin (n = 188) or cladribine (n = 45), to investigate the current long‐term outlook. Median follow‐up was 16 years. There were no significant differences in outcome between the two agents. Overall, the complete response (CR) rate was 80% and median relapse‐free survival was 16 years. After relapse (n = 79) or non‐response (n = 5), 26 patients received pentostatin and 58 cladribine; 69% achieved CR and median relapse‐free survival was 11 years. After third‐line therapy (n = 23), 50% achieved CR and median relapse‐free survival was 6·5 years. However, CRs were equally durable, whether after first, second or third‐line therapy. Complete responders and those with both haemoglobin >100 g/l and platelet count >100 × 109/l before treatment had the longest relapse‐free survival (P < 0·0001). Patients still in CR at 5 years had only a 25% risk of relapse by 15 years. Outcomes for patients with recurrent disease improved with the monoclonal antibody rituximab, combined with either purine analogue. Overall only eight patients died of HCL‐related causes. Patients achieving a CR can expect a normal lifespan.

Long remissions in hairy cell leukemia with purine analogs - A report of 219 patients with a median follow-up of 12.5 years

Both pentostatin and cladribine have efficacy in hairy cell leukemia (HCL), but it is not known which agent achieves better results.

ζ‐Chain associated protein 70 and CD38 combined predict the time to first treatment in patients with chronic lymphocytic leukemia

ζ‐Chain associated protein (ZAP)‐70 has been proposed as a surrogate marker for immunoglobulin heavy‐chain variable region (IgVH) mutation in chronic lymphocytic leukemia (CLL), but it is still not clear whether it is an independent prognostic factor.

The Role of Rituximab in Combination With Pentostatin or Cladribine for the Treatment of Recurrent/Refractory Hairy Cell Leukemia

The purine analogs pentostatin and cladribine have revolutionized the treatment of hairy cell leukemia (HCL) with overall responses in greater than 85% of patients and a median progression‐free survival of up to 15 years. They continue to be effective at second‐ and even third‐line therapy; however, alternative treatments are needed for patients who are or have become refractory to these agents or whose remissions are shorter with each course of therapy.

High-grade transformation in splenic marginal zone lymphoma with circulating villous lymphocytes: the site of transformation influences response to therapy and prognosis

In a series of 48 patients with splenic marginal zone lymphoma (SMZL) with circulating villous lymphocytes, we describe the clinical and laboratory features of nine cases that transformed to high‐grade B‐cell lymphoma. These patients had a significantly greater incidence of peripheral lymph node involvement at diagnosis when compared to SMZL patients who did not transform (P < 0·03). While transformation in the bone marrow is frequently refractory to therapy and associated with poor outcome in SMZL, lymph node transformation responds well to chemotherapy with durable progression‐free and overall survival.

Combinations of ZAP-70, CD38 and IGHV mutational status as predictors of time to first treatment in CLL

ZAP-70, CD38 and IGHV mutations have all been reported to have prognostic impact in chronic lymphocytic leukemia (CLL), both individually and in paired combinations. We aimed to determine whether the combination of all three factors provided more refined prognostic information concerning the treatment-free interval (TFI) from diagnosis. ZAP-70, CD38 and IGHV mutations were evaluated in 142 patients. Combining all three factors, the ZAP-70−/CD38−/Mutated group showed the longest median TFI (62 months, n = 37), ZAP-70+/CD38+/Unmutated cases the shortest (11 months, n = 37) and cases discordant for ≥1 factor, an intermediate TFI (27 months, n = 68) (p = 0.006). Analysis of discordant cases revealed values that were otherwise masked when measuring single prognostic factors. The presence or absence of cytogenetic abnormalities did not explain the variability among discordant cases. Simultaneous analysis of ZAP-70, CD38 and IGHV mutations in CLL provides more discriminatory prediction of TFI than any factor alone.

Transformation of T-cell large granular lymphocyte leukaemia into a high-grade large T-cell lymphoma.

We describe a case of T‐cell large granular lymphocyte (LGL) leukaemia that transformed into a large‐cell T‐cell lymphoma 11 years from diagnosis. A 29‐year‐old asymptomatic female presented in 1989 with lymphocytosis, neutropenia and mild bone marrow infiltration. The circulating cells were LGL with a CD2+, CD3+, CD8+, CD4–, CD16+, CD56+, CD57– phenotype. In August 2000, she developed fever, a large submandibular mass and hepatosplenomegaly. Biochemistry showed abnormal liver function tests and raised lactate dehydrogenase (LDH) levels. A serological screen for Epstein–Barr virus, cytomegalovirus, human T‐lymphotropic virus‐I, human herpes virus (HHV)‐6 and HHV‐7 was negative. Histology of the mass was consistent with the diagnosis of peripheral T‐cell lymphoma composed of large cells, and immunohistochemistry showed that the lymphoma cells had a phenotype identical to the mature LGL. Molecular analysis with the polymerase chain reaction (PCR) demonstrated rearrangement of the T‐cell receptor (TCR) γ‐chain gene with a band of identical size in both bone marrow mature LGL and lymph node cells. The patient was treated with CHOP (cyclophosphamide, vincristine, doxorubicin and prednisolone), resulting in the disappearance of the mass and improvement of the hepatosplenomegaly, LDH and liver abnormalities. She underwent splenectomy, and spleen histology showed involvement by T‐cell LGL leukaemia with no evidence of transformation. This case illustrates that transformation or Richter syndrome may occur in a minority of patients with T‐cell LGL leukaemia, a disease that has a benign clinical course in most cases. This is the first case documented by molecular methods of the transformation of the pre‐existing clone.

IgVH genes mutation and usage, ZAP-70 and CD38 expression provide new insights on B-cell prolymphocytic leukemia (B-PLL)

B-prolymphocytic leukemia (B-PLL) is a rare disease with poor prognosis. To further characterize the biological features of this disease, we analyzed immunoglobulin heavy chain (IgVH) mutations, ZAP-70 and CD38 in 19 cases with de novo B-PLL. Immunoglobulin heavy chain genes analysis showed an unmutated pattern (>98% homology to germ line) in 9/17 cases (53%), with 100% homology in eight. In the remaining, it ranged from 90 to 97.4%, with three cases slightly mutated (98–95%) and five heavily mutated (<95%). All B-PLL utilized members of VH3 (11/17) and VH4 (6/17) families, with V3-23, V4-59 and V4-34 gene accounting for more than half of them, regardless of mutational status. ZAP-70, assessed by flow cytometry, ranged from 1 to 91% cells, being ⩾20% in 57% of cases. CD38 ranged from 1 to 99% (median 21%). There was no correlation between IgVH status and ZAP-70 or CD38 expression, but male gender and del(17p) were more common in the unmutated group. Neither IgVH mutations, CD38 expression nor del(17p) influenced patients’ outcome. Unexpectedly, ZAP-70+ B-PLL patients survived longer (40 months) than ZAP-70− B-PLL (8 months). B-PLL appears biologically heterogeneous regarding IgVH mutations, ZAP-70 and CD38 expression, showing a pattern distinct from that of other lymphoproliferative disorders.

Histopathology of the spleen in T-cell large granular lymphocyte leukemia and T-cell prolymphocytic leukemia - A comparative review

We review retrospectively the spleen histology in 8 patients with T-cell large granular lymphocyte (LGL) leukemia and 4 with T-cell prolymphocytic leukemia (T-PLL) to identify characteristic patterns of involvement and to distinguish such patterns from those described in other low grade B- and T-cell malignancies. Moderate splenic enlargement with red pulp expansion due to lymphocytic infiltration was characteristic of LGL leukemia. Abnormal lymphocytes expressed cytotoxic granule proteins and were consistently CD45RO and CD5 negative in contrast to normal red pulp T cells. This infiltration respected anatomic boundaries with encroachment but no invasion of white pulp areas. Unlike in hairy cell leukemia, the main differential diagnosis for red pulp lymphocytosis, the white pulp was not only preserved in T-cell LGL leukemia but showed germinal center hyperplasia with expansion of the mantle zones. By comparison, T-PLL spleens showed marked red pulp lymphoid infiltration by medium-sized cells with irregular nuclei and prominent eosinophilic nucleoli. T-PLL lymphocytes, unlike LGLs, were more invasive, infiltrating the spleen capsule as well as white pulp areas. T-cell prolymphocytes did not express cytotoxic granule proteins or NK-cell markers, were CD5+, CD45RO+ like normal spleen T cells, were CD2+, CD3+, CD45+, CD43+, TCRβ+, but CD25−, CD30−, ALK-1−, TRAP−, DBA44−, and TdT−. Expression of CD4 and CD8 in these cells mirrored that of circulating T-PLL cells. These observations on the morphologic and immunohistochemical appearances of the spleen in T-cell LGL leukemia and T-PLL may aid diagnosis of these uncommon T-cell disorders, particularly T-cell LGL leukemia, where presentation may be cryptic and where unique pathognomonic features, are absent.

CD52 expression in T-cell large granular lymphocyte leukemia – Implications for treatment with alemtuzumab

Few reports on the successful treatment of T-cell large granular lymphocyte (LGL) leukemia with the humanized anti-CD52 monoclonal antibody alemtuzumab are emerging in the literature. The expression of CD52 by LGLs has not been previously investigated. Using semi-quantitative 2- and 3-color flow cytometry, we documented the expression of CD52 in 100% of abnormal cells in T-cell LGL leukemia (n = 11) and natural killer (NK) cell LGL leukemia (n = 2), and showed no significant difference in CD52 expression between T-cell prolymphocytic leukemia (PLL) and T-cell LGL leukemia. Higher CD52 expression has been noted in responders to alemtuzumab in T-cell PLL and in chronic lymphocytic leukemia (CLL), a B-cell disorder. The strong and consistent expression of CD52 shown here highlights the potential role of alemtuzumab in the treatment of refractory T-cell LGL leukemia and possibly aggressive NK cell leukemia.