Addition of etoposide to CHOP chemotherapy in untreated patients with high-grade non-Hodgkin's lymphoma

Double-strand break repair by interchromosomal recombination: an in vivo repair mechanism utilized by multiple somatic tissues in mammals

Homologous recombination (HR) is essential for accurate genome duplication and maintenance of genome stability. In eukaryotes, chromosomal double strand breaks (DSBs) are central to HR during specialized developmental programs of meiosis and antigen receptor gene rearrangements, and form at unusual DNA structures and stalled replication forks. DSBs also result from exposure to ionizing radiation, reactive oxygen species, some anti-cancer agents, or inhibitors of topoisomerase II. Literature predicts that repair of such breaks normally will occur by non-homologous end-joining (in G1), intrachromosomal HR (all phases), or sister chromatid HR (in S/G²). However, no in vivo model is in place to directly determine the potential for DSB repair in somatic cells of mammals to occur by HR between repeated sequences on heterologs (i.e., interchromosomal HR). To test this, we developed a mouse model with three transgenes—two nonfunctional green fluorescent protein (GFP) transgenes each containing a recognition site for the I-SceI endonuclease, and a tetracycline-inducible I-SceI endonuclease transgene. If interchromosomal HR can be utilized for DSB repair in somatic cells, then I-SceI expression and induction of DSBs within the GFP reporters may result in a functional GFP+ gene. Strikingly, GFP+ recombinant cells were observed in multiple organs with highest numbers in thymus, kidney, and lung. Additionally, bone marrow cultures demonstrated interchromosomal HR within multiple hematopoietic subpopulations including multi-lineage colony forming unit–granulocyte-erythrocyte-monocyte-megakaryocte (CFU-GEMM) colonies. This is a direct demonstration that somatic cells in vivo search genome-wide for homologous sequences suitable for DSB repair, and this type of repair can occur within early developmental populations capable of multi-lineage differentiation.

Parental longevity and prognosis in elderly patients with aggressive non-Hodgkin's lymphoma

In general, elderly patients with aggressive non-Hodgkin's lymphoma (NHL) have a less favourable prognosis than younger patients. Established predictors of prognosis in NHL are less discriminatory in the elderly, which is why there is a need for additional markers giving guidance on treatment decisions and prediction of outcome. The expected length of life of an individual in the general population is intimately associated with that of his/her parents. The aim of this study was to test the hypothesis that parental longevity is associated with improved outcome also among elderly patients with aggressive NHL and thus serves as an easily accessible non-disease associated prognostic factor. A total of 220 patients ( > 60 years) with aggressive NHL with a median age of 71 years (range 60-86) were included. Patients were randomized to receive CHOP or CNOP (doxorubicin replaced with mitoxantrone) chemotherapy with or without the addition of granulocyte colony-stimulating factor. The median follow-up time was 56 (19-89) months. Parental data regarding age at death were available through parish offices for 425 (97%) parents. Relative risk (RR) of death (disease-specific and all-cause) associated with parental lifespan was assessed using Cox proportional hazards regression analyses, with adjustment for sex, age, prognostic index, symptoms, and calendar period of diagnosis. Maternal lifespan below (versus above) median was associated with a borderline significant reduced disease-specific (adjusted RR of death from NHL = 1.5; 95% confidence interval 1.0-2.1) and overall survival. The effect of maternal lifespan was somewhat more pronounced in patients receiving CHOP than CNOP treatment. Paternal lifespan below the median was associated with a borderline significant increased disease-specific (adjusted RR of death from NHL = 0.8 [0.5-1.0]) and overall survival. Combined, maternal, and paternal lifespan had little impact on survival. These effects were true also when CHOP and CNOP treated patients were analysed separately. Maternal and paternal lifespan may predict survival in NHL, but with opposing effects. At present parental age appears not to be a clinically useful predictor of prognosis in the elderly with aggressive NHL.

Pharmacokinetic comparison of oral and intravenous etoposide in patients treated with the CHOEP-regimen for malignant lymphomas

BACKGROUND

The addition of etoposide to the CHOP protocol (CHOEP) has been shown to improve outcome in patients with aggressive non-Hodgkin's lymphoma. The intravenous administration of etoposide on three consecutive days represents a logistic problem and needs resources particular in the outpatient setting. This could be avoided by using etoposide capsules on days 2 and 3. However, the oral administration of cytotoxic agents is often affected by variable absorption and drug interactions.

PATIENTS AND METHODS

We investigated the pharmacokinetic equivalency of oral and intravenous etoposide in ten patients (male, n=7; female, n=3; median age 56 years) with aggressive lymphomas. Treatment consisted of standard CHOP plus etoposide 100 mg/m2 given intravenously on day 1, and 200 mg/m2 orally on days 3 and 4. Samples from blood and urine were taken on days 1 (i.v. study) and 3 (p.o. study) before and after etoposide administration. Etoposide levels were determined by high-performance liquid chromatography (HPLC), and pharmacokinetic parameters were calculated with the TOPFIT computer program.

RESULTS

Mean peak plasma level after intravenous etoposide was significantly higher compared to oral administration (16.3+/-3.7 vs. 12.0+/-4.2 microg/ml; P=0.015). The mean bioavailability of oral etoposide was 58+/-15% with an interpatient variability of 26%. Significant differences of bioavailability of oral etoposide between the used dose levels (350, 400 and 450 mg) were not observed. Mean AUC after a 100 mg/m2 intravenous and a 200 mg/m2 oral dose of etoposide were 74.0+/-18.3 and 84.9+/-29.6 microg h/ml (P=0.481). Interpatient variability of AUC was 25% for the intravenous route and 35% after oral intake. Urinary etoposide excretion as percentage of administered dose was 39.4+/-10.6% after intravenous infusion versus 35.4+/-9.4% after oral intake (P=0.422). Renal clearance was also very similar with intravenous and oral route (18.5+/-7.4 vs. 16.7+/-6.6 ml/min; P=0.546).

CONCLUSION

The equivalency of AUC after 200 mg/m2 of oral and 100 mg/m2 of intravenous etoposide support the use of the oral preparation in patients treated with the CHOEP regimen, which makes the chemotherapy more convenient for the patients and help to reduce costs.

Granulocyte function in elderly patients receiving chemotherapy for aggressive non-Hodgkin's lymphoma. Effect of granulocyte colony-stimulating factor

BACKGROUND: Treatment with granulocyte colony-stimulating factor (G-CSF) is given in order to mitigate chemotherapy-induced granulocytopenia and the risk of infectious complications, which constitute a major threat to elderly patients, in particular, with malignant disorders. The aim of this study was to evaluate whether G-CSF therapy would improve granulocyte defence mechanisms against infectious agents in this elderly, high-risk patient population. METHODS: Fourteen elderly (>60 years) patients with aggressive non-Hodgkin's lymphoma were enrolled in the study. Using flow cytometry we studied the expression of CD11b, before and after stimulation with fMLP, and CD16, as well as granulocyte metabolic activation measured as intracellular accumulation of dichlorofluorescein during induction chemotherapy. Eight patients were randomised to receive G-CSF treatment (5 &mgr;g/kg) on days 2-15. Granulocyte studies were done regularly during one 3-week cycle of chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP) or CNOP (doxorubicin substituted by mitoxantrone). RESULTS: Patients receiving G-CSF showed a faster restitution of granulocyte counts. Granulocyte CD11b expression following fMLP stimulation in vitro decreased during G-CSF therapy (P<0.005). A less pronounced (but not significant) reduction in CD16 expression was noted in the G-CSF-treated group. In contrast, fMLP-stimulated metabolic activation did not show consistent changes during the treatment cycle. Two episodes of infections during granulocytopenia that required hospitalisation were observed in each group. CONCLUSIONS: G-CSF treatment efficiently accelerated granulocyte recovery following chemotherapy. This probably compensates for the transient functional aberrations in circulating granulocytes observed in this patient group.

T-cell-rich B-cell lymphoma - diagnostic and therapeutic aspects

BACKGROUND

Morphologically, T-cell-rich B-cell lymphoma (TCRB-NHL) may be indistinguishable from Hodgkin's disease (HD). Immunophenotyping may be helpful in the separation of these entities. TCRB-NHL is occasionally misdiagnosed and treated as HD. However, information is limited regarding clinical characteristics and outcome of this patient population. Furthermore, knowledge concerning any association with Epstein-Barr virus (EBV) in TCRB-NHL, as well as the immunophenotype of reactive T-cells and the expression of T-cell intracellular antigen-1 (TIA-1), granzyme B (GrB) and the CD3-zeta-chain is limited.

PATIENTS AND METHODS

We have re-evaluated 251 tumour biopsies from patients aged > or =15 years with HD diagnosed 1985-1994. Reclassification from HD to TCRB-NHL was done in 12 cases (5%). Six TCRB-NHL patients initially diagnosed and treated as B-NHL were also included. All TCRB-NHL biopsies were analysed for latent membrane protein 1 (LMP-1), CD4, CD8, CD56, CD57, TIA-1, GrB and CD3-zeta-chain.

RESULTS

Twelve cases of TCRB-NHL were initially subclassified as HD (lymphocyte predominance 5, nodular sclerosis 3, and mixed cellularity 4). Of these 12 TCRB-NHL patients, 6 were given radiotherapy alone, 5 MOPP/ABVD or similar combination chemotherapy, and one patient combined modality treatment. Male sex (p<0.05) and inguinal involvement (p<0.001) were significantly more frequent when TCRB-NHL patients receiving HD treatment (n=12) were compared with the remaining patients with confirmed (conf) HD, while no significant differences were seen with regard to stage, bone marrow infiltration, splenomegaly or cause-specific survival. Similar results were achieved when all TCRB-NHL patients (n=18) were compared to conf HD patients. Lymphoma cells in three samples stained positively for LMP-1. A decreased expression of CD3-zeta-chain was seen in 9/14 tumour biopsies.

CONCLUSION

Immunohistochemistry makes it possible to identify cases of TCRB-NHL that are morphologically difficult to distinguish from HD. The outcome of TCRB-NHL patients treated as having HD was comparable with that of the remaining HD population.

Dose-escalated cyclophosphamide, doxorubicin, vincristine, prednisone, and etoposide (CHOPE) chemotherapy for patients with diffuse lymphoma: Cancer and Leukemia Group B studies 8852 and 8854

BACKGROUND

To address the feasibility and outcome of moderate dose intensification with granulocyte-colony stimulating factor (G-CSF) for patients with aggressive non-Hodgkin lymphoma (NHL), the Cancer and Leukemia Group B (CALGB) conducted two studies evaluating dose-escalated cyclophosphamide and etoposide in the cyclophosphamide, doxorubicin, vincristine, prednisone, etoposide (CHOPE) regimen.

METHODS

Eligibility criteria included histologically documented, diffuse small cleaved, diffuse mixed, diffuse large cell, or immunoblastic lymphoma, Stage III--IV or bulky Stage II disease, and an ECOG performance status of 0--1. CALGB 8852, a group-wide study, accrued 227 patients: 120 patients in the pilot study to determine the maximum tolerated dose (MTD) without G-CSF and 107 in the pilot study of dose-escalated CHOPE with G-CSF. CALGB 8854, a limited-institution, Phase I study, enrolled 38 patients and determined the MTD of CHOPE with G-CSF to be used in CALGB 8852. The MTD in both studies was defined as the dose at which 50% of patients had 1) Grade 4 neutropenia or thrombocytopenia lasting 7 days or more, or 2) Grade 3--4 hemorrhage or nonhematologic toxicity (excluding alopecia, nausea, and emesis), or 3) were prevented from receiving 100% of drug on Day 22.

RESULTS

The MTD of CHOPE without G-CSF was cyclophosphamide 1000 mg/m(2) on Day 1 and etoposide 100 mg/m(2) on Days 1--3 with doxorubicin 50 mg/m(2) on Day 1, vincristine 1.4 mg/m(2) (maximum, 2 mg) on Day 1, and prednisone 100 mg on Days 1--5. With the addition of G-CSF at 200 microg/m(2) on Days 5--19, the MTD was cyclophosphamide 1500 mg/m(2) and etoposide 160 mg/m(2) on Days 1-3 with standard doses of doxorubicin, vincristine, and prednisone. Increasing the dose of G-CSF from 200 microg/m(2) to 400 microg/m(2) did not allow for further dose escalation. The primary toxicity in all cohorts was neutropenia. Four toxic deaths occurred on CALGB 8852. The 5-year failure free survival (FFS) and overall survival (OS) rates for eligible patients on CALGB 8852 were 31% (95% confidence interval [95%CI], 23--39) and 48% (95%CI, 40--57), respectively. The 5-year FFS and OS rates for eligible patients on CALGB 8854 were 34% (95%CI, 17--52) and 51% (95%CI, 33--70), respectively.

CONCLUSIONS

Moderate dose escalation with G-CSF is feasible. However, response and survival rates of patients who receive dose-escalated CHOPE, even with the addition of G-CSF, appear similar to the rates reported with standard-dose CHOP.