Fludarabine-Melphalan-Campath, Followed by Unmanipulated Peripheral-Blood Haematopoietic Stem Cells, Can Still Cure Lymphoma.

Background: The second decade of this millennium was characterized by a widespread availability of chimeric antigen receptor T-cell (CAR-T) therapies to treat relapsed and refractory lymphomas. As expected, the role and indication of allogeneic haematopoietic stem cell transplant (allo-HSCT) in the management of lymphoma changed. Currently, a non-neglectable proportion of patients will be considered candidate for an allo-HSCT, and the debate of which transplant platform should be offered is still active. Objectives: to report the outcome of patients affected with relapsed/refractory lymphoma and transplanted following reduced intensity conditioning at King's College Hospital, London, between January 2009 and April 2021. Methods: Conditioning was with 150mg/m2 of fludarabine and melphalan of 140mg/m2. The graft was unmanipulated G-CSF mobilized peripheral blood haematopoietic stem cells (PBSC). Graft-versus-host disease (GVHD) prophylaxis consisted of pre-transplant Campath at the total dose of 60 mg in unrelated donors and 30 mg in fully matched sibling donors and ciclosporin. Results: One-year and five years OS were 87% and 79.9%, respectively, and median OS was not reached. The cumulative incidence of relapse was 16%. The incidence of acute GVHD was 48% (only grade I/II); no cases of grade III/IV were diagnosed. Chronic GVHD occurred in 39% of patients. TRM was 12%, with no cases developed within day 100 and 18 months after the procedure. Conclusions: The outcomes of heavily pretreated lymphoma patients are favorable, with median OS and survival not reached after a median of 49 months. In conclusion, even if some lymphoma subgroups cannot be treated (yet) with advanced cellular therapies, this study confirms the role of allo-HSCT as a safe and curative strategy.

UCART19, a first-in-class allogeneic anti-CD19 chimeric antigen receptor T-cell therapy for adults with relapsed or refractory B-cell acute lymphoblastic leukaemia (CALM): a phase 1, dose-escalation trial.

BACKGROUND: The prognosis for adults with relapsed or refractory B-cell acute lymphoblastic leukaemia remains poor. UCART19, an allogeneic genome-edited anti-CD19 chimeric antigen receptor (CAR) T-cell product derived from healthy donors and available for immediate clinical use, offers a potential therapeutic option for such patients. The CALM trial is a first-in-human study evaluating the safety and antileukaemic activity of UCART19 in adult patients with relapsed or refractory B-cell acute lymphoblastic leukaemia. METHODS: This phase 1, open-label study was conducted at eight centres across France, the UK, the USA, and Japan. Adult patients aged 16-70 years with CD19-positive relapsed or refractory B-cell acute lymphoblastic leukaemia who had morphological relapse or a minimal residual disease level of at least 1 × 10-3 and had exhausted standard treatment options were enrolled in the study, which comprised a dose-escalation phase of up to three UCART19 doses followed by a safety expansion phase. Patients underwent lymphodepletion with fludarabine (30 mg/m2 per day intravenously for 3 days) and cyclophosphamide (500 mg/m2 per day intravenously for 3 days) with or without alemtuzumab (1 mg/kg or 40 mg or 60 mg over 5 days) and received UCART19 doses of 6 × 106, 6-8 × 107, or 1·8-2·4 × 108 total CAR T cells intravenously, followed by safety evaluation and disease response assessments. The primary endpoint was incidence and severity of adverse events. Secondary endpoints were the overall response rate, duration of response, relapse-free survival, progression-free survival, and overall survival. This trial is registered with ClinicalTrials.gov (NCT02746952) and is complete. FINDINGS: Between Aug 1, 2016, and June 30, 2020, 25 patients were enrolled in the study and treated with UCART19. Median duration of follow-up was 12·8 months (IQR 2·8-24·8). Median age was 37 years (IQR 28-45). 14 (56%) patients were male and 11 (44%) female. 17 (68%) patients were White, two (8%) Black, two (8%) Asian, and four (16%) from other racial or ethnic groups. Three patients developed dose-limiting toxicities (one at each dose level); one had grade 4 cytokine release syndrome and two had grade 4 prolonged cytopenias. Grade 3 or higher cytokine release syndrome was reported in six (24%) patients and grade 3 or higher neurological toxicity in one (4%) patient. Grade 3 or higher infections occurred in seven (28%) patients, and grade 4 prolonged cytopenia in four (16%) patients. Two (8%) patients developed grade 1 acute cutaneous graft-versus-host disease. 14 patients died, nine from progressive disease and five from infections or other complications, of which four were considered to be related to UCART19 or lymphodepletion, or both. After a median of follow-up of 12·8 months (IQR 2·8-24·8), overall response rate was 48% (95% CI 28-69; 12 of 25 patients), duration of response and median relapse-free survival were 7·4 months (95% CI 1·8 to not calculable), progression-free survival was 2·1 months (95% CI 1·2-2·8), and overall survival was 13·4 months (95% CI 4·8-23·0). INTERPRETATION: UCART19 had a manageable safety profile, and showed evidence of antileukaemic activity in heavily pretreated adult patients with relapsed or refractory B-cell acute lymphoblastic leukaemia. This study shows that allogeneic off-the-shelf CAR T cells can be used safely to treat patients with relapsed B-cell acute lymphoblastic leukaemia. FUNDING: Servier.

Lymphoid blast crisis after prolonged treatment-free remission in chronic myeloid leukaemia after tyrosine kinase inhibitor de-escalation during the COVID-19 pandemic.

During the COVID-19 pandemic, access to health services has been considerably restricted and furthermore, patients have been reluctant to attend for routine monitoring, and this may have had a negative impact in the management of patients affected with haematological disorders. Sudden blast crisis in chronic myeloid leukaemia is categorized as a rapid onset of blastic phase, after a documented 'optimal' response to tyrosine kinase inhibitor (TKI) therapy and within 3 months of a normal complete blood count. Herein, we describe a case of patient who developed sudden blast crisis after TKI while in treatment-free remission.

Addition of four doses of rituximab to standard induction chemotherapy in adult patients with precursor B-cell acute lymphoblastic leukaemia (UKALL14): a phase 3, multicentre, randomised controlled trial.

BACKGROUND: Treatment for adults with acute lymphoblastic leukaemia requires improvement. UKALL14 was a UK National Cancer Research Institute Adult ALL group study that aimed to determine the benefit of adding the anti-CD20 monoclonal antibody, rituximab, to the therapy of adults with de novo B-precursor acute lymphoblastic leukaemia. METHODS: This was an investigator-initiated, phase 3, randomised controlled trial done in all UK National Health Service Centres treating patients with acute lymphoblastic leukaemia (65 centres). Patients were aged 25-65 years with de-novo BCR-ABL1-negative acute lymphoblastic leukaemia. Patients with de-novo BCR-ABL1-positive acute lymphoblastic leukaemia were eligible if they were aged 19-65 years. Participants were randomly assigned (1:1) to standard-of-care induction therapy or standard-of-care induction therapy plus four doses of intravenous rituximab (375 mg/m2 on days 3, 10, 17, and 24). Randomisation used minimisation and was stratified by sex, age, and white blood cell count. No masking was used for patients, clinicians, or staff (including the trial statistician), although the central laboratory analysing minimal residual disease and CD20 was masked to treatment allocation. The primary endpoint was event-free survival in the intention-to-treat population. Safety was assessed in all participants who started trial treatment. This study is registered with ClincialTrials.gov, NCT01085617. FINDINGS: Between April 19, 2012, and July 10, 2017, 586 patients were randomly assigned to standard of care (n=292) or standard of care plus rituximab (n=294). Nine patients were excluded from the final analysis due to misdiagnosis (standard of care n=4, standard of care plus rituximab n=5). In the standard-of-care group, median age was 45 years (IQR 22-65), 159 (55%) of 292 participants were male, 128 (44%) were female, one (<1%) was intersex, and 143 (59%) of 244 participants had high-risk cytogenetics. In the standard-of-care plus rituximab group, median age was 46 years (IQR 23-65), 159 (55%) of 294 participants were male, 130 (45%) were female, and 140 (60%) of 235 participants had high-risk cytogenetics. After a median follow-up of 53·7 months (IQR 40·3-70·4), 3-year event-free survival was 43·7% (95% CI 37·8-49·5) for standard of care versus 51·4% (45·4-57·1) for standard of care plus rituximab (hazard ratio [HR] 0·85 [95% CI 0·69-1·06]; p=0·14). The most common adverse events were infections and cytopenias, with no difference between the groups in the rates of adverse events. There were 11 (4%) fatal (grade 5) events in induction phases 1 and 2 in the standard-of-care group and 13 (5%) events in the standard-of-care plus rituximab group). 3-year non-relapse mortality was 23·7% (95% CI 19·0-29·4) in the standard-of-care group versus 20·6% (16·2-25·9) in the standard-of-care plus rituximab group (HR 0·88 [95% CI 0·62-1·26]; p=0·49). INTERPRETATION: Standard of care plus four doses of rituximab did not significantly improve event-free survival over standard of care. Rituximab is beneficial in acute lymphoblastic leukaemia but four doses during induction is likely to be insufficient. FUNDING: Cancer Research UK and Blood Cancer UK.

Clinical and prognostic significance of small paroxysmal nocturnal hemoglobinuria clones in myelodysplastic syndrome and aplastic anemia.

In this large single-centre study, we report high prevalence (25%) of, small (<10%) and very small (<1%), paroxysmal nocturnal hemoglobinuria (PNH) clones by high-sensitive cytometry among 3085 patients tested. Given PNH association with bone marrow failures, we analyzed 869 myelodysplastic syndromes (MDS) and 531 aplastic anemia (AA) within the cohort. PNH clones were more frequent and larger in AA vs. MDS (p = 0.04). PNH clone, irrespective of size, was a good predictor of response to immunosuppressive therapy (IST) and to stem cell transplant (HSCT) (in MDS: 84% if PNH+ vs. 44.7% if PNH-, p = 0.01 for IST, and 71% if PNH+ vs. 56.6% if PNH- for HSCT; in AA: 78 vs. 50% for IST, p < 0.0001, and 97 vs. 77%, p = 0.01 for HSCT). PNH positivity had a favorable impact on disease progression (0.6% vs. 4.9% IPSS-progression in MDS, p < 0.005; and 2.1 vs. 6.9% progression to MDS in AA, p = 0.01), leukemic evolution (6.8 vs. 12.7%, p = 0.01 in MDS), and overall survival [73% (95% CI 68-77) vs. 51% (48-54), p < 0.0001], with a relative HR for mortality of 2.37 (95% CI 1.8-3.1; p < 0.0001) in PNH negative cases, both in univariate and multivariable analysis. Our data suggest systematic PNH testing in AA/MDS, as it might allow better prediction/prognostication and consequent clinical/laboratory follow-up timing.

Genome-edited, donor-derived allogeneic anti-CD19 chimeric antigen receptor T cells in paediatric and adult B-cell acute lymphoblastic leukaemia: results of two phase 1 studies.

BACKGROUND: Genome-edited donor-derived allogeneic anti-CD19 chimeric antigen receptor (CAR) T cells offer a novel form of CAR-T-cell product that is available for immediate clinical use, thereby broadening access and applicability. UCART19 is one such product investigated in children and adults with relapsed or refractory B-cell acute lymphoblastic leukaemia. Two multicentre phase 1 studies aimed to investigate the feasibility, safety, and antileukaemic activity of UCART19 in children and adults with relapsed or refractory B-cell acute lymphoblastic leukaemia. METHODS: We enrolled paediatric or adult patients in two ongoing, multicentre, phase 1 clinical trials to evaluate the safety and antileukaemic activity of UCART19. All patients underwent lymphodepletion with fludarabine and cyclophosphamide with or without alemtuzumab, then children received UCART19 at 1·1-2·3 × 106 cells per kg and adults received UCART19 doses of 6 × 106 cells, 6-8 × 107 cells, or 1·8-2·4 × 108 cells in a dose-escalation study. The primary outcome measure was adverse events in the period between first infusion and data cutoff. These studies were registered at ClinicalTrials.gov, NCT02808442 and NCT02746952. FINDINGS: Between June 3, 2016, and Oct 23, 2018, seven children and 14 adults were enrolled in the two studies and received UCART19. Cytokine release syndrome was the most common adverse event and was observed in 19 patients (91%); three (14%) had grade 3-4 cytokine release syndrome. Other adverse events were grade 1 or 2 neurotoxicity in eight patients (38%), grade 1 acute skin graft-versus-host disease in two patients (10%), and grade 4 prolonged cytopenia in six patients (32%). Two treatment-related deaths occurred; one caused by neutropenic sepsis in a patient with concurrent cytokine release syndrome and one from pulmonary haemorrhage in a patient with persistent cytopenia. 14 (67%) of 21 patients had a complete response or complete response with incomplete haematological recovery 28 days after infusion. Patients not receiving alemtuzumab (n=4) showed no UCART19 expansion or antileukaemic activity. The median duration of response was 4·1 months with ten (71%) of 14 responders proceeding to a subsequent allogeneic stem-cell transplant. Progression-free survival at 6 months was 27%, and overall survival was 55%. INTERPRETATION: These two studies show, for the first time, the feasibility of using allogeneic, genome-edited CAR T cells to treat patients with aggressive leukaemia. UCART19 exhibited in-vivo expansion and antileukaemic activity with a manageable safety profile in heavily pretreated paediatric and adult patients with relapsed or refractory B-cell acute lymphoblastic leukaemia. The results this study are an encouraging step forward for the field of allogeneic CAR T cells, and UCART19 offers the opportunity to treat patients with rapidly progressive disease and where autologous CAR-T-cell therapy is unavailable. FUNDING: Servier.

Outcomes of older patients with primary central nervous system lymphoma treated in routine clinical practice in the UK: methotrexate dose intensity correlates with response and survival.

Data on older patients with primary central nervous system lymphoma (PCNSL) are scarce. Comorbidities and performance status frequently compromise outcomes in this group. Medical records for consecutive patients ≥65 years (n = 244) with PCNSL diagnosed 2012-2017 from 14 UK centres were retrospectively reviewed. Of these 192 patients received methotrexate (MTX)-based treatment. Patients were categorised based on clinician's treatment choice into 'palliative' (n = 52), 'less intensive: MTX ± rituximab ± alkylators' (n = 74) and 'intensive: MTX/cytarabine combinations' (n = 118) groups. Complete remission (CR) rate, two-year progression-free survival (PFS) and overall survival (OS) rates were 49%, 11% and 24% for the less intensive and 69%, 40% and 50% for the intensive groups. Treatment-related mortality (TRM) was 6·8% for MTX-treated patients. Median MTX cumulative dose was 8·8 g/m2 (range 1·5-21) over a median of three cycles. Higher relative dose intensity of MTX (MTX-RDI) was associated with improved PFS and OS in both groups adjusting for age, Eastern cooperative oncology group (ECOG) score and baseline parameters. Two-year PFS and OS for patients receiving four or more induction cycles followed by consolidation (n = 36) were 65% and 70% respectively. Older patients completing MTX-based induction and consolidation had clinical outcomes similar to those in younger cohorts. These retrospective data suggest that maximising MTX-RDI and delivering consolidation in a subgroup of older patients may improve clinical outcomes.

Induction therapy with the MATRix regimen in patients with newly diagnosed primary diffuse large B-cell lymphoma of the central nervous system - an international study of feasibility and efficacy in routine clinical practice.

The MATRix chemoimmunotherapy regimen is highly effective in patients with newly diagnosed primary diffuse large B-cell lymphoma of the central nervous system (PCNSL). However, nothing is known about its feasibility and efficacy in everyday practice, where patients are more often older/frailer than those enrolled in clinical trials. We conducted a retrospective study addressing tolerability/efficacy of MATRix in 156 consecutive patients with newly diagnosed PCNSL treated outside a clinical trial. Median age and ECOG Performance Status of considered patients were 62 years (range 28-78) and 2 (range 0-4). The overall response rate after MATRix was 79%. Nine (6%) treatment-related deaths were recorded. After a median follow-up of 27.4 months (95% confidence interval [CI] 24.4-31.9%), the two-year progression-free and overall survival were 56% (95% CI 48.4-64.9%) and 64.1% (95% CI 56.7-72.5%) respectively. Patients not eligible for the IELSG32 trial were treated with lower dose intensity and had substantially worse outcomes than those fulfilling inclusion criteria. This is the largest series of PCNSL patients treated with MATRix outside a trial and recapitulates the IELSG32 trial outcomes in the non-trial setting for patients who fit the trial criteria. These data underscore the feasibility and efficacy of MATRix as induction treatment for fit patients in routine practice.

The architecture of neoplastic follicles in follicular lymphoma; analysis of the relationship between the tumor and follicular helper T cells.

CD4+ T-follicular helper cells are essential for the survival, proliferation, and differentiation of germinal center B cells and have been implicated in the pathogenesis of follicular lymphoma (FL). To further define the role of these cells in FL, we used multiparameter confocal microscopy to compare the architecture of normal and neoplastic follicles and next generation sequencing to analyze the T-cell receptor repertoire in FL lymph nodes (LN). Multiparameter analysis of LN showed that the proportion of T-follic-ular helper cells (TFH) in normal and neoplastic follicles is the same and that the previously reported increase in TFH numbers in FL is thus due to an increase in the number and not content of follicles. As in normal germinal centers, TFH were shown to have a close spatial correlation with proliferating B cells in neoplastic follicles, where features of immunological synapse formation were observed. The number of TFH in FL correlate with the rate of B-cell proliferation and TFH co-localized to activation induced cytidine deaminase expressing proliferating B cells. T-cell receptor repertoire analysis of FL LN revealed that follicular areas are significantly more clonal when compared to the rest of the LN. These novel findings show that neoplastic follicles and germinal centers share important structural features and provide further evidence that TFH may play a role in driving B-cell proliferation and genomic evolution in TFH Our results also suggest that targeting this interaction would be an attractive therapeutic option.

A retrospective analysis of post-transplant lymphoproliferative disorder following liver transplantation.

OBJECTIVE: To evaluate response rates and survival in adults developing post-transplant lymphoproliferative disorder (PTLD) following liver transplantation. METHODS: Patients were identified retrospectively and data collected through local liver and haematology electronic databases and pharmacy records. RESULTS: Forty-five patients were identified. The median age at first transplant and at development of PTLD was 48 and 54 years, respectively, with the median time from transplant to PTLD diagnosis of 56 months. The majority of cases (76%) were monomorphic B-cell lymphomas, and 36% of tumours were EBV positive. Treatment involved reduction in immune-suppression (RIS) in 30 (67%) with RIS the only treatment in 3. Ten (22%) patients were treated with rituximab alone, 13 (29%) with chemotherapy alone and 14 (31%) patients were treated with rituximab and chemotherapy. Twenty-six (58%) patients achieved a complete response (CR). At a median follow-up of 27 months, the median overall survival (OS) was 50 months. Response and OS were not associated with clinical factors or the use of rituximab. CONCLUSION: Outcomes reported in this study are favourable and comparable to those reported previously. The addition of rituximab did not appear to have improved outcomes in this series, although a significant proportion of patients were able to avoid chemotherapy.

Outpatient management of steroid-induced hyperglycaemia and steroid-induced diabetes in people with lymphoproliferative disorders treated with intermittent high dose steroids.

High dose steroids (HDS) are used in the treatment of haematological malignancies. The reported risk of steroid-induced diabetes (SID) is high. However, screening is not consistently performed. We implemented a protocol for detection and management of SID and steroid-induced hyperglycamia (SIH) in haematology outpatients receiving HDS. Eighty-three people were diagnosed with a lymphoproliferative disorder, of whom 6 had known Type 2 diabetes. Fifty-three people without known diabetes were screened by HbA1c and random venous plasma glucose. All patients (n = 34) subsequently prescribed HDS checked capillary blood glucose (CBG) pre-breakfast and pre-evening meal. Treatment algorithms used initiation and/or dose titration of gliclazide or human NPH insulin, aiming for pre-meal CBG 5-11 mmol/l. Type 2 diabetes was identified in 4/53 people screened (7.5%). Of 34 people treated with HDS, 17 (44%) developed SIH/SID. All 7 people with Type 2 diabetes developed SIH and 3 required insulin. Of 27 people without known diabetes, 8 (30%) developed SID and 1 required insulin. Pre-treatment HbA1c was higher in people who developed SID compared to those that did not (p = 0.002). This is the first report of a SID/SIH detection and treatment protocol for use in people with lymphoproliferative disorders receiving intermittent HDS, demonstrating its feasibility and safety.

Outcome for patients with relapsed/refractory aggressive lymphoma treated with gemcitabine and oxaliplatin with or without rituximab; a retrospective, multicentre study.

The treatment of relapsed aggressive lymphoma remains a challenge. Platinum-containing chemotherapy is standard of care. Gemcitabine/oxaliplatin (Gem-Ox) with or without rituximab (R) is an outpatient regimen with a favorable toxicity profile. This retrospective 'real world' study reports outcomes for 44 unselected patients with relapsed/refractory aggressive lymphoma treated with Gem-Ox ± R. 41% had primary refractory disease. The overall response rate (ORR) was 43% with a complete response (CR) of 30%. Response to the prior treatment regimen significantly affected the ORR with only 8% achieving CR if prior remission was <12 months. Grade 3-4 hematological toxicity was common and 22% had febrile neutropenia. Eight patients proceeded to stem cell transplant. Overall, outcomes remain poor with a median overall survival of 8 months. In this high-risk group of patients, Gem-Ox ± R results in similar responses to other more toxic, inpatient regimens and should therefore be considered as second line therapy in relapsed lymphoma.

Phenotype and immune function of lymph node and peripheral blood CLL cells are linked to transendothelial migration.

Several lines of evidence suggest that homing of tumor cells to lymphoid tissue contributes to disease progression in chronic lymphocytic leukemia (CLL). Here, we demonstrate that lymph node (LN)-derived CLL cells possess a distinct phenotype, and exhibit enhanced capacity for T-cell activation and superior immune synapse formation when compared with paired peripheral blood (PB) samples. LN-derived CLL cells manifest a proliferative, CXCR4(dim)CD5(bright) phenotype compared with those in the PB and higher expression of T-cell activation molecules including CD80, CD86, and HLA-D-related (DR). In addition, LN-CLL cells have higher expression of α4ß1 (CD49d) which, as well as being a co-stimulatory molecule, is required for CLL cells to undergo transendothelial migration (TEM) and enter the proliferation centers of the LNs. Using an in vitro system that models circulation and TEM, we showed that the small population of CLL cells that migrate are CXCR4(dim)CD5(bright) with higher CD49d, CD80, CD86, and HLA-DR compared with those that remain circulating; a phenotype strikingly similar to LN-derived CLL cells. Furthermore, sorted CD49d(hi) CLL cells showed an enhanced capacity to activate T cells compared with CD49d(lo) subpopulations from the same patient. Thus, although PB-CLL cells have a reduced capacity to form immune synapses and activate CD4(+) T cells, this was not the case for LN-CLL cells or those with the propensity to undergo TEM. Taken together, our study suggests that CLL cell immunologic function is not only modulated by microenvironmental interactions but is also a feature of a subpopulation of PB-CLL cells that are primed for lymphoid tissue homing and interaction with T cells.

Long term follow-up of BEAM-autologous and BEAM-alemtuzumab allogeneic stem cell transplantation in relapsed advanced stage follicular lymphoma.

This is an analysis in 171 patients comparing BEAM-Auto and BEAM-Allo (alemtuzumab)-hematopoietic stem cell transplantation in relapsed follicular lymphoma. BEAM-Allo group had a lower 10 years cumulative incidence of relapse(31.4% vs 55.1%, p=0.042), a trend to a plateau in survival but no statistical differences in OS or DFS, and a TRM of 24%. When transplanted in CR BEAM-Allo patients had better OS and DFS. Incidence of acute and chronic GVHD was 16.6% and 22%. 29% of BEAM-Allo patients received DLI (all but two remain in CR and alive). Our data supports Allo-HSCT as a potential curative treatment for selected patients with FL.

Recent childbirth is an adverse prognostic factor in breast cancer and melanoma, but not in Hodgkin lymphoma.

BACKGROUND: The relationship between gestation, childbirth and cancer prognosis is unknown for most cancers (e.g. Hodgkin lymphoma), whereas a body of evidence exists for melanoma and breast cancer. METHODS: The national cancer registration and hospital discharge data for women in England (1998-2007) were linked, and the records for Hodgkin lymphoma, melanoma and breast cancer were indexed as to whether women had delivered a child in separate time periods prior to their cancer diagnosis. Survival analyses were conducted in order to characterise prognosis in relation to childbirth, with statistical adjustment for age and (where possible) stage. FINDINGS: For melanoma and breast cancer, survival was strongly reduced in women who gave birth in the year prior to cancer diagnosis. The age-adjusted hazard ratios (HR) with 95% confidence intervals (CI) were 2.06 (1.42-3.01) for melanoma and 1.84 (1.64-2.06) for breast cancer. The associations were only slightly attenuated by further adjustment for tumour stage. For breast cancer, the excess death rate in women with a recent childbirth peaked at 2 years and remained elevated for 6 to 8 years. Previous childbirth had no overall effect on the outcome of Hodgkin lymphoma. INTERPRETATION: Melanoma and breast cancer prognosis are adversely affected by recent gestation and childbirth in a way that is not due to stage of the cancer, but rather to inherent biological properties of the tumours. Possible biological mechanisms include immunosuppression (melanoma), the hormonal milieu in gestation and a tumour promoting microenvironment post-partum (breast cancer).

Mimicking the tumour microenvironment: three different co-culture systems induce a similar phenotype but distinct proliferative signals in primary chronic lymphocytic leukaemia cells.

Interactions in the tumour microenvironment can promote chronic lymphocytic leukaemia (CLL) cell survival, proliferation and drug resistance. A detailed comparison of three co-culture systems designed to mimic the CLL lymph node and vascular microenvironments were performed; two were mouse fibroblast cell lines transfected with human CD40LG or CD31 and the third was a human microvascular endothelial cell line, HMEC-1. All three co-culture systems markedly enhanced CLL cell survival and induced a consistent change in CLL cell phenotype, characterized by increased expression of CD38, CD69, CD44 and ITGA4 (CD49d); this phenotype was absent following co-culture on untransfected mouse fibroblasts. In contrast to HMEC-1 cells, the CD40LG and CD31-expressing fibroblasts also induced ZAP70 expression and marked CLL cell proliferation as evidenced by carboxyfluorescein succinimidyl ester labelling and increased Ki-67 expression. Taken together, our data show that co-culture on different stroma induced a remarkably similar activation phenotype in CLL cells but only the CD40LG and CD31-expressing fibroblasts increased ZAP70 expression and CLL cell proliferation, indicating that ZAP70 may play a critical role in this process. This comparative study reveals a number of striking similarities between the co-culture systems tested but also highlights important differences that should be considered when selecting which system to use for in-vitro investigations.